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To minimize in the system level the designed mass of Thermoelectric Integrated Membrane Evaporation Subsystem (TIMES) of Environment Control Life Support System (ECLSS) in manned spacecraft, when the requirement of the production rate of fresh water and its hygiene is fulfilled.According to the characteristics of the operational process of TIMES, the physical and mathematical model for fluid flow, heat transfer and mass composition in its main parts were established to investigate numerically the relation between the system mass and those parameters associated with the structure and operation of the system.The system mass depended not only on the structural parameters and operational parameters of TIMES, but also on the operational characteristics of power subsystem and thermal control subsystem. The relative mass covered a large part of the system mass.There existed an optimum of the number of thermoelectric cooling parts and flow rate of circular waste water of the TIMES when the designed system mass was minimum. Moreover, higher condensation pressure in the system contributed to lower system mass.

In mammals, preparation of donor cells for somatic nuclear transfer is very important because the character of the donor cell directly affects the efficiency and outcome of transfer. The protocols used most commonly for donor preparation are (i) disaggregating cells from fresh tissue 1-2 h before micromanipulation or (ii) trypsinizing cultured cells temporarily, after special treatments for 3-8 days (for example, serum starvation). In this study, a new simple protocol was designed, whereby the donor cells (cumulus cells) used in bovine somatic nuclear transfer were refrigerated. In brief, cultured cells at 80-100% confluency were detached using trypsin, washed by centrifugation, aliquoted into different vials and refrigerated at 4 degrees C. The density of viable cells was decreased after day 1 of refrigeration; however, the rate of decrease tended to slow down with increasing duration of refrigeration. Cells refrigerated for 15 days were seeded at a density of 5 x 10(4) ml(-1) and reached 70% confluency after day 2 of culture. Most cells had the normal number of chromosomes (2n = 60). Cells chilled at 4 degrees C for different durations were removed from refrigeration and immediately subjected to micromanipulation. The in vitro development of reconstructed embryos (fusion rates, cleavage rates, morula and blastocyst rates) indicated that there were no significant differences among treatment groups regardless of the duration of refrigeration (0-2 weeks) of the donor cells. Reconstructed embryos were transferred into the uteri of recipient cows. No significant differences were observed in established early pregnancies between embryos derived from the non-refrigerated donor cells and those derived from refrigerated donor cells. This study indicates that refrigeration of donor cells for 1-2 weeks is a feasible protocol for preparing donor cells for bovine somatic nuclear transfer, and does not compromise development in vitro and early development in vivo.

To deal with the mass optimization of thermal control system as well as environmental control and life support system (ECLSS) of manned spacecraft.The thermo-hydraulic network composed of coupled liquid dual-loop and gas loops was studied. Physical and mathematical models were established and used for flow, heat transfer and mass calculation in the network. The influences of various operational and structural parameters on the mass were analyzed.There were optimal pipe diameters for internal loop and external loop; there existed an upper limit of flow rate in the internal loop and lower limit in the external loop; there were also optimal flow rates in the loops and optimal exit temperature of the radiator.Reasonable design of these parameters were very important for reducing the system mass.

In order to clarify the frequency of p16INK4 gene inactivation and its relationship with retinoblastoma (Rb) gene expression in non-small cell lung cancer, in situ double hybridization was established with Bio-labelled Rb cDNA probe and Dig-lablled p16INK4 cDNA probe, and immunohistochemistry was carried out with polyclone rabbit antibodies to human p16INK4 and Rb protein. The results showed that positive hybridization of p16INK4 mRNA showed blue with the detecting system of alkiline phosphatase NBT/BCIP, positive hybridization of Rb mRNA showed red with the detecting system of HPR-AEC. The negative ratios of p16INK4 and Rb gene transcription were 22.6%(7/31) and 16.1%(5/31). The results of immunohistochemistry showed that the negative ratio of p16INK4 protein was 42%(13/31) with p16INK4 polyclone antibody, the negative ratio of pRb was 19.4%(6/31) with polyclone antibody. The data indicated that p16INK4 gene and Rb gene are synergistic in the progression of lung cancer, p16INK4 gene plays a significant role in the development of non-small cell lung cancer.

Previously, we showed that NO induces thymocyte apoptosis via a caspase-1-dependent mechanism [(1) ]. In the present study, we investigated the role of heme oxygenase, catalase, bax, and p53 in this process. The NO donor, S-nitroso-N-acetyl penicillamine (SNAP), induced DNA fragmentation in thymocytes in a time- and concentration-dependent way. SNAP (100 microM) induced 50--60% apoptosis; higher doses did not increase the rate of apoptosis significantly. SNAP decreased catalase and heme iron (Fe) levels without affecting superoxide dismutase, glutathione, or total Fe stores in thymocytes. SNAP significantly increased the expression of heme oxygenase 1 (HSP-32), p53, and bax but not bcl-2. Treatment with the heme oxygenase inhibitor, tin protoporphyrin IX inhibited SNAP-induced thymocyte apoptosis. Furthermore, thymocytes from p53 null mice were resistant to NO-induced apoptosis. Our data suggest that NO may induce its cytotoxic effects on thymocytes by modulating heme oxygenase and catalase activity as well as up-regulating pro-apoptotic proteins p53 and bax.

Repeated tetanus (60 Hz, 0.4-0.6 mA, 2 s) were delivered into the right and the left dorsal hippocampus (HPC), or into the right and the left medial temporal neocortex (MTNC) respectively to establish chronic temporal lobe epilepsy model in rats. The possible role of the HPC-Entorhinal cortex (EC)-MTNC-Neocortex neural pathway in epileptogenesis was discussed based on observing the abnormalities in behavior and in EEG or depth electrographes and in T2-weighted magnetic resonance images (T2-MRI).1. Occurrence of primary, secondary WEDS and kindling effects were higher in the right dorsal HPC experimental group than those in other three experimental groups (P0.005, P0.001). T2-MRI signal hyperintensity was remarkable in lateral ventricles close to the HPC (P0.05), but not in the EC or in the MTNC. 2. These T2-MRI intensity increases were related to behavioral abnormalities in some MTNC-stimulated rats. 3. Asymmetric behavioral abnormalities and T2-MRI changes were observed in the left and the right DHPC-stimulated groups.HPC may be an "origin" for epileptogenesis and EC may play a "gating" role in it.

The solution structure of diadenosine 5',5'''-P1,P4-tetraphosphate hydrolase from Lupinus angustifolius L., an enzyme of the Nudix family, has been determined by heteronuclear NMR, using a torsion angle dynamics/simulated annealing protocol based on approximately 12 interresidue NOEs per residue. The structure represents the first Ap4A hydrolase to be determined, and sequence homology suggests that other members will have the same fold. The family of structures shows a well-defined fold comprised of a central four-stranded mixed beta-sheet, a two-stranded antiparallel beta-sheet and three helices (alphaI, alphaIII, alphaIV). The root-mean-squared deviation for the backbone (C',O,N,Calpha) of the rigid parts (residues 9 to 75, 97 to 115, 125 to 160) of the protein is 0.32 A. Several regions, however, show lower definition, particularly an isolated helix (alphaII) that connects two strands of the central sheet. This poor definition is mainly due to a lack of long-range NOEs between alphaII and other parts of the protein. Mapping conserved residues outside of the Nudix signature and those sensitive to an Ap4A analogue suggests that the adenosine-ribose moiety of the substrate binds into a large cleft above the four-stranded beta-sheet. Four conserved glutamate residues (Glu55, Glu58, Glu59 and Glu125) form a cluster that most likely ligates an essential magnesium ion, however, Gly41 also an expected magnesium ligand, is distant from this cluster.

We investigate the influence of the grain size on the thermal diffusivity of pure Al2O3 ceramics by using mirage effect. Results show that the value of thermal diffusivity decreases with increasing grain size, when the grain size of the sample is smaller than 200 nm, and the value of that increases with increasing grain size when the grain size is larger than 200 nm. The detailed experiments, the results, analyses, discussions are presented in this paper.

We have investigated the generation of Rayleigh‐type surface acoustic waves in high‐resistance CdS crystals under the action of the third harmonic of the YAG:Nd3+ pulsed laser. A linear dependence of the acoustic signal amplitude with applied external electric field and its saturation with increasing illumination intensity has been observed. Experimental results show that the acoustic wave excitation is due to the inverse piezoeffect in which an external electric field is screened by a dense photogenerated electron‐hole plasma. The saturation effect is caused by a nonlinear recombination of nonequilibrium carriers that prevents from increasing the screened part of the crystal volume.

Colcemid (COM) was tested for induction of meiotic delay and aneuploidies in meiotic metaphase II (MMII) of male(101/E 1 XC 3 H/E 1)F 1 mice post single intraperitoneum (i.p.) injection. The dose of 1 mg/kg of COM was used and sampled at 2, 6, 10, 14 and 18 h after COM treatment. The number of MMII and MMI were the highest at 2 and 6 h repectively, and decreased rapidly with lengthening of COM treatment and reached the lowest at 14 h; then increased. However, the ratio of MMII to MMI was always significantly higher than in solvent control at every sample interval. Under our experimental conditions, COM did not show aneugenicity in male mouse germ cells. The possible mechanisms by which COM caused meiotic delay and reasons that COM did not induce aneuploidy in MMII were discussed.

Several chemiluminescence-based reactions are applicable to the determination of various bio-pharmaceutically important analytes, and they can be applied for monitoring chemiluminescence emission using flow injection, liquid chromatographic and capillary electrophoretic analysis, as well as for the development of chemiluminescence-based sensors or in immunoassays. As in general the emission intensity is linearly proportional to the concentration of any of the reagents, the technique allows the analysis of different species involved in the light-producing reaction, amongst which are the chemiluminescent reagent, oxidants, inhibitors, cofactors, catalysts, some fluorophore, etc. The present overview illustrates some important applications of the last decade on this rather unfamiliar luminescence technique to detectional challenges in the liquid phase. The required instrumentation is limited as no external light source is needed. Also, the technique opens perspectives for increasing detection sensitivity in miniaturized flowing streams. On the other hand, several drawbacks still limit full application, eg dependence of the emission signal upon a number of environmental factors forcing the analyst to make a compromise between separating and measuring conditions, a lack of selectivity in specific cases, the critical detection of the signal at strictly defined periods, especially in the case of sharp emission vs time profiles, and the development of detection devices in capillary electrophoresis.

We preliminary investigate the non-homogeneity on a small area within composite by using laser ultrasonic probe. Two kinds of composites are used as samples. One of them is aluminum matrix reinforced by SiC fiber with diameter of 0.156 mm (SiC/Al). The other is polymer matrix reinforced by stain-steel needle with diameter of 0.35 mm (needle/polymer). The non-homogeneity of composite is investigated by measuring the time-of-flight (TOF) of the laser exciting longitudinal (L-) and transverse (T-) waves which propagate within the samples. The influence of the number of fibers on the non-homogeneity of TOF is observed. Results show that, the non-homogeneity of TOF on a small area within a composite can be observed with resolution of 1 ns in time domain and 50 μm in space. The sensitivity of detection of the non-homogeneity by using T-wave is good than by using L-wave. The TOF of T-wave becomes short, while that of L-wave becomes length when the detection point is passing through the point where the fiber or needle is lied in. For the sample with two fibers, the rise and fall of TOF became small. The detail results and discussions will be presented in this article.

Patients with schizophrenia (DSM IV, n = 149) and controls (n = 180) participated in a case-control association study in which a trinucleotide repeat polymorphism of pancreatic phospholipase A2 group 1B (PLA2G1B) was examined. Both African-American and Caucasian populations were included in this USA sample. There were no significant case-control differences, therefore his study does not support an association between schizophrenia and a PLA2G1B polymorphism on chromosome 12. © 1999 Lippincott Williams & Wilkins.

The polymorphics of two pericentric (GT)n sequences on the long arm of human chromosome 21 have been analyzed after PCR amplification, PAGE and Ag-staining for the first time in 50 Chinese Han people, and were used to detect meiotic origin of the extra chromosome 21 in Down syndromes. Six and 5 alleles were found in Chinese Han people for D21S215 and D21S120, respectively, with observed heterozygosities of 0.68 and polymorphic information content PIC, 0.67 and 0.65. For 17 Down syndromes whose parental origin of the extra chromosome 21 were known, meiotic origin of the extra chromosome 21 were determined in 16 cases, with 7 and 4 maternal meiosis I and II nondisjunction, 2 and 3 paternal meiosis I and II, respectively. The possible biological significance of the study on origin of the extra chromosome 21 has been discussed.

There is considerable controversy regarding a putative association between schizophrenia and a biallelic BalI polymorphism in the first exon of the dopamine D3 receptor gene (DRD3), although meta-analyses of published data suggest an association. If such an association exists, it may be detectable at markers physically close to DRD3. Accordingly, we conducted a case-control association study using D3S1310, a short tandem repeat polymorphism located approximately 700 kb telomeric to DRD3 on chromosome 3q13.3. The subjects were Swedish patients with schizophrenia (DSM III-R criteria, n = 110) and screened adult controls (n = 83). A trend for a negative association with the 141 bp allele was detected (chi2 = 7.6, d.f. = 1, P = 0.006; odds ratio 0.46, 95% confidence intervals 0.26, 0.81). However, following corrections for multiple comparisons using subgroups (n = 15) the difference was not significant. Also, due to the risk for population stratification in case-control association studies the results must be treated as tentative. If replicated the results may lend further support for the proposition of an association between schizophrenia and DRD3 or a gene in close proximity to DRD3 on chromosome 3q.

Anisotropie media are of great importance in practice and in scientific research. Orthogonal (Orth.) crystal is a favorite crystal with simplest anisotropic structure and large nonlinear optical properties. However it is difficult to grow large and pure. During the growth crystals, if not taking care, some tetragonal (Tetr.) crystal phase will be mixed in it. It is difficult to make measurement of anisotropic conductivity for in this medium. According to the theory of lattice heat conduction, conductivity is related to lattice phonon state density (i.e. related to lattice constants and its texture). So the tensor of thermal conductivity for Orth. crystal is different with that for Tetr. crystal. Thus measurement of anisotropic heat conductivity is of considerable importance. From such measurement, we may detect the anisotropic conductivity and yield information of purity of Orth. crystal

The highest efficiency of light conversion into surface acoustic wave (SAW) has been achieved by laser action on a photoconducting piezocrystal, with the simultaneous application of an external electric field[1]. A theoretical analysis[2] supports the opinion of reference [1] that SAW excitation was primarily carried out by the inverse piezoeffect in the nonstationary electric fields induced by spatial separation of optically generated charge carriers ( i.e. instantaneous inverse piezoeffect). Their estimations show that the magnitude of conversion efficiency of optical power into SAW signal voltage obtained here may be three to seven orders higher than that obtained previously by thermoelastic mechanism of optoacoustic transformation. Telenkov et. al., [3] investigated the generation of SAW in high resistance CdS crystals under the action of a third harmonic of the YAG: Nd3+ pulsed laser. Experimental results show that the SAW excitation is due to the inverse piezoeffect. A linear dependence of the acoustic signal amplitude with applied external electric field is found. However, nobody analyses and calculates the property of surface displacement, as well as discuss the relationship between the distributions of surface displacement and properties of materials in frequency and time domains. It is worth for practical application.

In recent years, there has been increasing interest in nanostructured ceramic materials because of their advanced properties. The superplasticity; improved strength and toughness, higher densification rate and low sintering temperature are observed in these materials[1–4]. The sintering speed vsintering of ceramic is related to the grain size d by the expression of vsin ting ∝d-4 [2]. By adding the nano-particles of Al2O3 to conventional Al2O3, the strength, fracture toughness and thermal resistance of Al2O3 ceramic can increase[5]. Up to now, only a few researchers[6,7] have concerned about the specific heat and thermal expansion of nano- ceramics, and no report about thermal diffusivity of nano-composite has been found in literature. However, characterizations of thermal diffusivity of nanocomposite ceramics are very important for designing and preparing this kind of new materials.

Studies of brain anatomy and premorbid functioning indicate that schizophrenia may be of neurodevelopmental origin. In the neurotrophic factor neurotrophin-3 (NT-3) gene, the A3/147-bp allele in a dinucleotide repeat polymorphism located in the promoter region was found to be associated with schizophrenia in a Japanese study. Another NT-3 polymorphism (Glu63Gly) indicated an association with schizophrenic patients with a putative neurodevelopmental form of the disease. We examined Swedish schizophrenic patients (n = 109) and control subjects (n = 78) for the same two NT-3 polymorphisms, as well as a third silent exonic polymorphism (at Pro55). No significant difference was found between the two groups. However, in a meta-analysis including the present and previous studies of Caucasian subjects, the A3/147-bp allele frequency was found to be significantly higher in the schizophrenic patients. In the present study, carriers of the A3/147 bp allele tended to have an earlier age of onset and to display more extrapyramidal symptoms. In the silent exonic polymorphism (at Pro55), female schizophrenic patients had higher adenine and lower guanine allele frequencies than control female subjects. Together with previous studies, the results provide some support for an association between the NT-3 gene and certain forms of schizophrenia. This warrants further investigation of NT-3 and other neurotrophic factors with additional polymorphisms and larger patient samples.

A flow injection analysis method is proposed for the determination of tiopronin based upon the oxidation by cerium(IV) in dilute sulfuric acid medium and sensitized by quinine. With the peak height as a quantitative parameter applying optimum working conditions, tiopronin is determined over the 1-400 microM range (150 microliters per injection, n = 10, r = 0.9994) with a detection limit of 0.34 microM and an RSD (n = 10) less than 2% at 20 and 50 microM. The proposed method, combining the advantages of speed and sensitivity, was applied to the routine determination of tiopronin in a pharmaceutical preparation.

Using a case-control design, an association of schizophrenia with the dopamine D3 receptor gene (D3RG) locus was investigated. Initial analysis of pooled results from published studies revealed a significant excess of individuals homozygous for either allele among the patients. The association was next tested in two cohorts ascertained independently at Pittsburgh, Pennsylvania and at Houston, Texas. The Pittsburgh sample was comprised of patients with schizophrenia (DSM-III-R) (n = 130). The controls belonged to two groups: adults screened for the absence of substance abuse or major psychiatric illness (n = 128), and neonates (n = 160). Multivariate analysis suggested an association with allele 1 of the biallelic D3RG polymorphism in comparison with the adult, but not the neonatal, controls. The association was most marked among Caucasian patients with a family history of schizophrenia (odds ratio 13.69, confidence intervals 1.80, 104.30). Survival analysis suggested an earlier age of onset among male patients homozygous for allele 2. The Houston cohort included Caucasian patients with schizophrenia or schizoaffective disorder (DSM-III-R criteria, n = 50), and normal controls matched for gender (n = 51). In this group, no significant associations were noted among all the patients or among subgroups of patients based on family history or age of onset. Possible reasons for the discordant results are discussed.

Lung cancer has been one of the leading malignancies in China. Since 1989 it has ranked first among common malignancies in the male population, and second in females. In 1975, a multimodality treatment study group for lung cancer was organized in our institute. The group has since expanded to 15 institutions in the Beijing and Tianjin area during the past four years. The present communication is based on our experiences and data, and tries to explain the treatment strategy of our study group.

To characterize the effect of added fibronectin (Fn) on human rheumatoid synoviocytes (RAS).Early passage cultured RAS were studied by fluorescent imaging microscopy with multiple parameter overlaying and confocal laser scanning microscopy.Added Fn induced a localized decrease in matrix Fn at sites of cell overlap. Similar matrix depletion could be induced by collagen VI, cell binding (120 k) and heparin binding (60 k) fragments of Fn, but not by gelatin binding fragment (45 k).The decrease in matrix Fn was associated with the induction of a transformation-like phenotype of overlapping cell growth. Both phenomena were inhibited by serine protease inhibitors.

Thermal difrusivity is one of the important physical properties of composite materials, no matter it is used as structural or functional elements. The determination of thermal diffusivity of composite is important. Copper-Carbon and Silver-Carbon fiber composites (here after Cu-Cf and Ag-Cf) possess the properties of both of Cu and Carbon fiber. The properties of the composite are adjusted within a certain range by changing the volume and/or arrangement of carbon fiber. Thus to study the thermal difrusivity of Cu-Cf as a function of the volume fraction and the arrangement of Carbon fiber is significant for seeking the condition of that the composite with light weight, high strength, appropriate thermal diffusivity and electrical conductivity, for example, it is possible to make Cu-Cf near to metal element Mo. ‘Mirage effect’ method used first by Kuo et. al.[1] is a useful tool for determination thermal diffusivity of materials. The advantages of it are local, contactless and sensitive. So far, the value of thermal difrusivity for isotropic materials from the lowest value 5 10E-5 cm 2/ s of polymer to the highest 18.5 cm2/s of diamond respectively were obtained by Kuo et. al.[2,3]. The anisotropic thermal difrusivity was measured by Zhang et. al.[4]. However few of the reports are related to composites [5].

Polymethyl methacrylate (PMMA) is a kind of typical amorphous polymer, whose main mechanical property is viscoelasticity that can be of great importance in materials characterization and nondestructive evaluation (NDE). On the other hand, ultrasonic NDE technique is one of the basic methods to characterize polymeric materials. By the measurements of the velocity and attenuation of the bulk waves as a function of frequency and temperature [1–3], the moduli of PMMA can be deduced and various relaxation phenomena can be investigated. However, as we know, the studies on the SAW attenuation of PMMA have not been reported. It is difficult for the contact ultrasonic method to do so because the effect of the electric transducers working in the contact way on the SAW field can not be avoided. Some disadvantages of using electronic ultrasonic method to characterize polymers, such as the measurement must be made in the immersion apparatus and the piezoelectric transducers with different frequencies must be used to obtain the attenuation spectra etc. have been overcome by the means of the laser ultrasonic technique [4,5]. The noncontact nature of the laser ultrasonic technique can also eliminate the effect of the contact measurement on the SAW field and make it convenient for the measurement at elevated temperatures. Therefore the laser ultrasonic technique is extremely suitable for the study on the attenuation of SAW.

From Sep. 1989 to Dec. 1992, 122 evaluable patients with small cell lung cancer (SCLC) treated with chemotherapy combined with radiotherapy in our hospital were analysed. There were 95 men and 27 women. The age ranged from 20 to 70 years. All were proven by pathology or cytology. They all did not receive previous treatment and had a measurable mass. Of them, 83 patients had limited disease (LD) and 39 extensive disease (ED). Using CE-CAP alternating chemotherapy, 48 LD and 27 ED were given two cycles, 35 LD and 12 ED four cycles. In this series, remission time was not evaluated because all patients received radiotherapy shortly after chemotherapy. Of 122 patients, 10 patients (8.2%) achieved CR, 89 (72.9%) PR, 18 (14.7%) S and 5 (4%) P. The total response rate was 81.1% (99/122), which is higher than that of COMVP and PE-CAV regimens. The response rates were 80.0% and 82.9% in two and four cycle groups, respectively. There was no significant difference between the two groups. The main toxicity observed was nausea, vomiting and bone marrow suppression, but were tolerated by the patients. In conclusion, CE-CAP regimen can be recommended as the treatment of choice in SCLC.

By means of polymerase chain reaction (PCR) technique, direct smear fluorescence microscopy and bacterial culture, the sputa and purulent secretions of 122 TB patients were examined to detect Mycobacterium tuberculosis. The results were as following, the positive rate of PCR was 56.9% (58/102). The positive rate of direct smear fluorescence microscopy was 23.5% (24/102) and that of bacterial culture was 14.7% (15/102). Our investigation shows that PCR technique is sensitive. The positive rate of PCR is largely consistent with the clinical diagnosis. Compared with bacterial culture, PCR is a time-saving practice. It is a recommendable method in diagnosis of TB.

Nd-Fe-B permanent magnets doped with a small amount of praseodymium (Pr) nanoparticles were prepared by conventional sintering method. Effects of the Pr nanoparticles doping amount and the sintering temperature on the magnetic properties of the magnets were studied. As the doping amount increases, the coercivity of the magnets rises gradually, while the remanence and the maximum energy product of the magnets rise first, peak at 1.0 wt. % of Pr nanoparticles doping, then drop. The optimal sintering temperature was determined as 1040 °C. Under optimal doping amount and sintering temperature, the Nd-Fe-B magnet bears good magnetic properties of Br of 1.386 T, Hci of 1170 kA/m and (BH)max of 371 kJ/m3, which are better than the Pr-free magnet’s magnetic properties of Br of 1.358 T, Hci of 1097 kA/m and (BH)max of 354 kJ/m3, suggesting the doping of Pr nanoparticles is a promising way to enhance the magnetic properties of sintered Nd-Fe-B magnets.

Using a case-control design, a reported association of schizophrenia with homozygosity at the dopamine D3 receptor gene locus was investigated in a group of patients (n = 53), with schizophrenia (DSM-III-R), and psychiatrically normal controls (n = 61), matched for ethnicity and area of residence. No significant differences in the distribution of alleles or genotypes between the two groups could be deteched. However, among patients with a family history of schizophrenia, as compared to controls without such family history, an association with allele 1 at this locus was noted (Odds ratio 12.4, C.I. 1.61, 96.35). © 1993 Wiley-Liss, Inc.

The determination of PPD-antibody in specimens of 42 blood, 16 cerebrospinal fluid and 31 pleural cavity fluid from tuberculosis patients and the blood specimens of 160 donors were carried out with solid phase radioimmunoassay (SPRIA). The positive rates of their PPD antibodies were 90.5%, 68.8%, 77.4% and 5% respectively. The positive rates of same specimens determined with ELISA assay were 50.0%, 38.5%, 40.9% and 6.3% respectively. SPRIA is as specific as ELISA, but the former is more sensitive than the latter.

A total of 720 human intestinal helminthic infections were divided into 4 groups and treated with albendazole 400mg/d x 3d, 400mg/d x 5d, pyrantel 1,500mg/d x 3d, or 1,500mg/d x 5d. Half a month after treatment, the negative rates of hookworm egg were 98.6, 98.6, 86.2 and 93.5%, those of ascaris egg were 96.5, 98.2, 92.9 and 96.3%, and those of whipworm egg were 86.4, 89.0, 68.9 and 67.0% respectively. Reduction rate of hookworm egg reached more than 98% in all the 4 groups. Six months after treatment, however, the positive rates of all the 4 groups rose again in varying degrees. The predominant species of hookworm infections was Necator americanus before the treatment and Ancylostoma duodenale after the treatment. It was demonstrated that the recurrence of hookworm infection resulted from A. duodenale infections, while a single dose of 400mg albendazole per day for 3 or 5 days showed good effect in controlling the recurrence of hookworm infections in a certain area.

The jet instability and bubble frequencies in a single-orifice 2-D gas-solid fluidized bed were studied by flow visualization and measured by means of a high-sensitivity capacitance probe. The influence of a series of parameters, including particle size (0.105–0.590 mm), particle density (590–3990 kg/m3), probe vertical location, jet flow rate ( 0.5 x 10 -4 −35 x 10 -4 m 1 /3 ) and background gas flow rate (0–4 times minimum fluidization velocity), on the bubble frequency was investigated. For the smallest particle size studied, the jet instability frequency was in good agreement with a 2-D version of a simple model due to Davidson and Harrison. The data show a systematic deviation from that model for increasing particle size. The model is then modified to account for the fact that with large particles, gas leakage from the forming bubble to the surrounding emulsion phase becomes important. The modified leakage model agrees well with the experimental data. Bubble coalescence at the tip of the jet was shown to result in bubble frequencies which are simple subharmonics of the basic pinching frequencies of the jet.