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To investigate the current prevalence of human soil-borne nematode infections in Yunnan province, so as to provide the scientific evidence for formulating the soil-borne nematodiasis control strategy in the province.In 2015, a total of 20 survey sites were sampled in 10 counties (cities) of Yunnan Province using the stratified cluster random sampling method. Stool samples were collected from all local permanent residents at ages of one year and older in each survey site, and the soil-borne nematode eggs were identified using the modified Kato-Katz technique and the egg number was counted. In addition, the hookworm species was identified using the filter-paperculture method, andA total of 5 067 residents received stool examinations, and 950 residents were detected with soil-borne nematode infections, with an overall prevalence rate of 18.75%. The prevalence ofThe prevalence of human soil-borne nematode infections remains high in Yunnan Province. The management of soil-borne nematodiasis requires to be reinforced among low-age children, farmers, old people and residents with low educations levels or ethnic groups.

Increasing marine uptake of anthropogenic CO2 (C-ant) causes global ocean acidification. To obtain a high-resolution spatiotemporal distribution of oceanic carbon chemistry, we developed new parameterizations of the seawater total alkalinity, and dissolved inorganic carbon from the ocean's surface to 2,000-m depth by using dissolved oxygen, water temperature (T), salinity (S), and pressure (P) data. Using the values of total alkalinity and dissolved inorganic carbon predicted by dissolved oxygen, T, S, and P data derived from autonomous biogeochemical Argo floats, we described the distribution of oceanic C-ant in the 2000s in the subarctic North Pacific at high spatiotemporal resolution. The C-ant was found about 300 m deeper than during the 1990s; its average inventory to 2,000 m was 24.8 +/- 10.2 mol/m(2), about 20% higher than the 1990s average. Future application of parameterizations to global biogeochemical Argo floats data should allow the detailed global mapping of spatiotemporal distributions of CO2 parameters. Plain Language Summary:Age Cy Ocean absorbs the increasing atmospheric CO2 by human activities from 1750s and encourages global ocean acidification. To obtain the human-activity-derived CO2 in the subarctic North Pacific in a high resolution, we applied our empirical ocean carbon chemistry equations using other hydrographic parameters to autonomous biogeochemical Argo floats data. The amount of human-activity-derived CO2 in this region was found about 300 m deeper than during the 1990s and about 20% higher than the 1990s average. Our method allows the development of a system for monitoring long-term trend changes in ocean carbon chemistry similar to other time series stations.

目的 探讨微小残留病（MRD）水平在Ph染色体阴性的急性B淋巴细胞白血病（Ph− B-ALL）中的预后意义。 方法 采用多色流式细胞术对2010年9月至2017年11月初诊的193例Ph− B-ALL患者在治疗后1、3、6个月进行骨髓MRD监测，并对不同MRD水平患者的预后进行比较。 结果 中位随访22（1~92）个月，所有193例患者共行497次MRD检测。1个月时MRD水平

Objectives: To analyse the concentration of interleukin (IL)-27 and IL-23 in serum and urine of patients with systemic lupus erythematosus (SLE) compared with healthy controls (HC).Method: An enzyme-linked immunosorbent assay (ELISA) was used to analyse the serum and urine concentration of IL-27 and IL-23 from 50 patients with lupus nephritis (LN), 55 patients without LN, and 30 HC. The correlations between the levels of IL-27, IL-23, and disease activity, clinical parameters in SLE patients were analysed.Results: The levels of IL-27 and IL-23 increased significantly in the serum and urine of SLE patients with and without LN compared with HC. Moreover, urine levels of IL-27 and IL-23 were correlated with the renal SLE Disease Activity Index (rSLEDAI) score and 24-h urinary protein levels. After 6 months of immunosuppressive treatment, urine IL-27 expression rose significantly in SLE patients with LN.Conclusions: IL-27 and IL-23 may be involved in the pathogenesis of LN.

pH‐Zone‐refining countercurrent chromatography was applied to the separation of alkaloids from a crude extract of green tea using a multilayer coil planet centrifuge. After methyl tert‐butyl ether and water were equilibrated, triethylamine (10 mM) was added to the organic phase as a retainer and hydrochloric acid (10 mM) was added to the aqueous phase as an eluter. The separation was performed by eluting the aqueous phase while the organic phase was used as the stationary phase. From 3 g of the extract, 2.2 g caffeine and 0.07 g theophylline were separated within about 4 h.

High efficiency Al–N cermet solar selective coatings have been designed using a numerical computer model and deposited experimentally. In numerical modeling calculations, Bruggeman approximations of dielectric function for composite materials were employed. Aluminum is used as a metallic component and AlON as a ceramic component in cermet. Numerical calculation results show that the double cermet layer film structure has the highest photothermal conversion efficiency for the Al–AlON cermet solar selective coatings. The optimized film has a solar absorptance of 0.958 and a hemispherical emittance of 0.035 at 80 °C. The optimized film yields two cermet layers with metal volume fractions of 0.143 and 0.275, and with layer thicknesses of 43 and 80 nm, going from the antireflection coating to the infrared reflector layer. In the optimized double cermet layer film the solar radiation is efficiently absorbed internally and by phase interference. Thermal loss is also efficiently reduced by using thin cermet layer...

On the basis of successful research into new metal–aluminium nitride (M–AlN) cermet solar selective coatings, a commercial-scale cylindrical direct current (dc) magnetron sputter coater has been developed for the deposition of these cermet solar coatings onto batches of tubes. The coater vacuum chamber has a diameter of 0.8 m and is 1.8 m in height. 32 glass tubes may be accommodated in the chamber. Stainless steel–aluminium nitride (SS–AlN) cermet material has been investigated as a solar absorbing layer. Three cylindrical post cathodes, consisting of stainless steel, aluminium and copper tubes, are installed in the chamber. During the deposition of an SS–AlN cermet layer, both the Al and SS targets are sputtered simultaneously in the gas mixture of argon and nitrogen. The nitrogen partial pressure is set sufficiently high at the aluminium target side to ensure that a nearly pure AlN ceramic sublayer is deposited by dc reactive sputtering. The planetary rotation of the 32 tubes results in a multi-layered system consisting of alternating SS and AlN sublayers. This multi-sublayer system can be considered as a macro-homogeneous cermet layer. Varying SS target current achieves different SS volume fractions in the cermet layers. A solar absorptance of 0.94–0.95 and emittance of 0.04–0.05 at room temperature has been achieved for the SS–AlN cermet solar coatings. These solar tubes are stable at 330–400°C. Using this commercial-scale coater, it should be possible to produce solar tubes stable at even higher temperatures (450–550°C), based on a high melting point transition metal–aluminium nitride cermet.

A cylindrical direct current (dc) magnetron sputtering system of commercial scale for coating glass tubes with metal–aluminium nitride (M–AlN) cermet solar selective surfaces is described. The stainless steel–aluminium nitride (SS–AlN) cermet material has been investigated as a solar absorbing layer. During the deposition of a SS–AlN cermet layer, both an Al metal target and stainless steel target are sputtered simultaneously in a gas mixture of argon and nitrogen. The nitrogen partial pressure is set sufficiently high at the aluminum target side to ensure that a nearly pure AlN ceramic sublayer is deposited onto the surrounding tubes by dc reactive sputtering. The excellent nitriding resistance of stainless steel leads to a nearly pure SS sublayer being deposited onto the tubes. Tube planetary rotation results in a deposited multi-layered system consisting of alternating SS and AlN sublayers. This multi-sublayer system can be considered as a macro-homogeneous cermet layer with the metal volume fraction d...

Two preparations of glutamate receptors were purified from the synaptic junctions of pig brain by a combination of detergent solubilization, anion-exchange chromatography, wheat-germ agglutinin affinity chromatography and sedimentation through sucrose gradients. These preparations were enriched in specific L-[3H]glutamate binding activity (> 5000 pmol of glutamate binding sites/mg of protein), and the rank order of ligand affinity for binding to these preparations was: quisqualate > 6-cyano-7-nitroquinoxaline-2,3-dione > α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) > L-glutamate > kainate ≫ N-methyl-D-aspartate≈ L-2-amino-4-phosphonobutyrate. SDS/PAGE analysis revealed that more than 80% of the protein in either of these preparations appeared as a single protein band of 106 kDa. Two-dimensional gel electrophoresis further revealed that these 106 kDa proteins consisted of a series of acidic proteins which were recognized by antibodies against rat AMPA receptor subunits. These 106 kDa proteins were also recognized by wheat-germ agglutinin and concanavalin A; in addition, peptide N-glycosidase F treatment of these preparations decreased their size to 99 kDa. Our results suggest that the putative glutamate receptors isolated here are likely to belong to the AMPA subtype of glutamate receptors in pig brain. Using the purification procedure reported here, 5 µg of AMPA receptor proteins can be isolated from 250 g of pig brain tissue.

By means of symplectic group Sp(2M), the symplectic symmetry of the Hubbard model and the η pairing are investigated to approach the eigenstates which have the largest spin multiplicities. The behavior of the off‐diagonal long‐range order of these eigenstates is examined by the criterion proposed by Yang and the energy diagram of the corresponding eigenvalues is elucidated by the η pairing mechanism. A basis set which is expressible in terms of η and ηa pairings is proposed.

Because no ECG lead cable and lead selector is equipped, SYD-4228 Physiology Experiment System can not be used to record and observe ECG. This paper introduces an ECG lead converter/selector designed and implemented by us.With resistor network and lead input cable, an ECG lead converter/selector was produced.As an independent and assistant part of SYD-4228 system, this ECG lead converter/selector can be used to record ECG waveform in animal experiment.Capable of matching both SYD-4228 system and other ECG recording systems, this ECG lead converter/selector can record ECG waveforms with different lead systems simultaneously. Real-time observation and comparison of waveforms recorded by different lead systems can be available.

In recent years, the issue of whether medical care should be given to impaired neonates has given rise to widely divergent views among practitioners of medicine, law and ethics. The general public also holds wide-ranging opinions on this subject. The divergence centres on whether medical care should be given to seriously impaired neonates, on whom should make decisions in these matters, and who should perform acts of euthanasia, in accordance with the current climate of opinion in China. This opinion has been focused both on ethical principles and on relevant precepts relevant to the "value of life." The author presents his opinions and explanations on the rights of impaired neonates, the rights and duties of parents and medical staff, and his views on the application of beneficence relative to this subject.

Sarcoidosis is a multi-system granulomatous disorder of unknown cause that presents more frequently in young adults with bilateral hilar adenopathy, pulmonary infiltrates, and skin or eye lesions. The multisystem clinical manifestations of this disease are a diagnostic challenge to all physicians. Although the clinical and pathological characteristics of sarcoidosis are well described, the decision to treat and the optimal therapy are less well defined. We report two patients of systemic sarcoidosis with cutaneous manifestations of the disease. Gallium whole body scintigraphy was performed and showed increased activity over the bilateral pulmonary hilar region (lambda sign), lacrimal and parotid glands (panda sign).

Cells resist the major mutagenic effects of alkylating agents by the action of O6-methylguanine-DNA methyltransferase (MGMT), which transfers the alkyl (R) group of O6-alkylguanine, produced in DNA by these chemicals, to a cysteine residue in its active site (formation of R-MGMT). We demonstrate that cellular R-MGMT (which represents a record or memory within the cells exposed to these chemicals) can be assayed by its sensitivity toward proteolysis by protease V8. The possible use of this assay for monitoring exposure to alkylating carcinogens was investigated by using cultured cells and a preliminary study with the use of human blood from normal subjects and patients undergoing chemotherapy. Cultured cell experiments show that R-MGMT is sufficiently stable for the monitoring purpose and its level bears a dose-response relationship to the concentrations of the alkylating agent used. Interestingly, experiments with blood from patients undergoing chemotherapy show a gradual formation of R-MGMT in 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea and an induced MGMT deficiency in cyclophosphamide-treated patients. The use of this methodology, which allows for the possible quantification of active MGMT (cellular DNA repair capacity) and R-MGMT (recent exposure) simultaneously, in monitoring human exposure to alkylating carcinogens is discussed.

A quantitative assay of immunofluorescence is described that can be performed on individual cells from standard pathologic specimens using fluorescence microscopy. The technique has been applied to measurement of O6-methylguanine-DNA methyltransferase, a DNA repair protein that is a molecular marker for resistance to chloroethylnitrosources used in cancer chemotherapy. The immunofluorescence assay makes use of monoclonal antibodies with specificity for human transferase, fluorescence microscopy with digital imaging, fluorescent bead internal standards, and computerized image analysis. This method is specific for the transferase, produces results correlated with activity measurements, and yields new data about tissue heterogeneity and subcellular localization previously unavailable with standard assay methods.

The human DNA repair enzyme, methylguanine-DNA methyltransferase (MGMT, M(r) 21,000), which protects cells against the mutagenic effect of alkylating carcinogens, was found to be localized in the cell nucleus (except the nucleolus) by immunofluorescence staining using polyclonal and monoclonal antibodies. The supporting experiments came from differential staining of the MGMT-deficient (mer-) and -proficient (mer+) cells, Western blotting analysis, and specific antibody depletion studies with the immobilized fusion protein, GSTMGMT-glutathione-Sepharose. Its localization in the nucleus agrees with its biological function and possibly explains the ineffective protection of mammalian cells (mer-) transfected with the Escherichia coli MGMT genes from bifunctional alkylating agents.

Thirty-base-pair synthetic oligonucleotide duplexes containing a single meG.C (meG = 6-O-methylguanine) or A.C base pair at the 16th position (i.e., 5'-CCCGTTTAAATATACXTATACCCGGGTACC-3', where X = A or meG) were used to study de novo methylation by the purified human DNA (cytosine-5)-methyltransferase isolated from CEM cells. Both duplexes containing meG.C and A.C base pairs show enhanced methyl group acceptor properties. Subsequent introduction of hemimethylated sites at the 15th position of the top strand (the C residue next to the abnormal base pair) and the 7th, 15th (which represents the C residue in the 6meG.C and A.C base pairs), and 27th positions of the bottom strand were used to study the maintenance methylation of the hemimethylated duplexes by the methylase. This revealed striking differences in the rate, amount, and sites of methylation, which are dependent on the position of the hemimethylated site in the duplex. The possible mechanism of action of the methylase is discussed. The data show that 6-O-methylguanine residues in DNA can have other genetic effects apart from their miscoding behavior and that meG.C and A.C base pairs exert different effects in terms of methylation.

Structural features at extra thymidine bulge sites in DNA duplexes have been elucidated from a two-dimensional NMR analysis of through-bond and through-space connectivities in the otherwise self-complementary d(C-C-G-T-G-A-A-T-T-C-C-G-G) (GTG 13-mer) and d(C-C-G-G-A-A-T-T-C-T-C-G-G) (CTC 13-mer) duplexes in aqueous solution. These studies establish that the extra thymidine flanked by guanosines in the GTG 13-mer duplex is in a conformational equilibrium between looped out and stacked states. The looped-out state is favored at low temperature (0 degrees C), whereas the equilibrium shifts in favor of the stacked state at elevated temperatures (35 degrees C) prior to the onset of the duplex-strand transition. By contrast, the extra thymidine flanked by cytidines in the CTC 13-mer duplex is looped out independent of temperature in the duplex state. Our results demonstrate that temperature and flanking sequence modulate the equilibrium between looped-out and stacked conformations of single base thymidine bulges in DNA oligomer duplexes.

The irreducible tensor mthcd is extended fran continuous group to the system with point group synetry. coefficient fran SO(3) to octahedral group is introduced for sktplifying the calculation of matrix elmnts. the spectra of praseodymim penta phosphate is presented. Especially, the V-coupling As an application, the analysis of

Self-complementary dodecadeoxynucleotides containing either one O6-methylguanine (O6-meGua), one O6-ethylguanine (O6-etGua) or one O4-methylthymine (O4-meT) have been synthesized. They form double-stranded DNA in solution. The structures of these DNA helices containing O6-meGua:cytosine (C), O6-meGua:thymine (T), O6-etGua:C and Gua:O4-meT base pairs have been investigated by nuclear magnetic resonance (NMR). All these modified bases stack into the helix with the normal anti-glycosidic torsion angle; only in the helix containing an O6-etGua:C base pair was there evidence of significant distortion of the DNA structure. NMR did not show a strong hydrogen bond between N1 of Gua and N3 of O4-meT in the Gua:O4-meT base pair, or between N1 of O6-meGua and N3 of T in the O6meGua:T base pair. This casts doubt on the previously accepted structures for O4-meT:Gua and O6-meGua:T mispairs.

Self-complementary oligodeoxynucleotides have been synthesized containing O6-methylguanine (O6meG), O6-ethylguanine (O6etG), O6-isopropylguanine (O6iprG) and O4-methylthymine (O4meT). They anneal in solution to give double-stranded DNA. These double helices have been used as substrates for the DNA repair protein O6-alkylguanine-DNA-alkyltransferase coded for by the ada gene of Escherichia coli. The repair followed second-order chemical kinetics. O6meG was repaired by the 19-kd transferase at a rate of 2.54 x 10(7) M-1 s-1 which is close to the theoretical limit for a diffusion-controlled reaction; O6etG and O4meT are repaired 1,000 and 10,000 times more slowly. The 39-kd alkyltransferase (which is precursor to the 19-kd form) and the 19-kd transferase repaired O6etG at similar rates. O6iprG was not repaired. The repair of oligomers containing O6meG was only slightly inhibited by the presence of nonalkylated oligomers. Oligomers containing O6etG were only slightly more effective as inhibitors of repair than the nonalkylated oligomers, indicating that the transferase does not bind selectively to alkylated DNA. Parallel structural studies have shown that O6-alkylguanine:C and O4-alkylthymine:A base pairs have a similar geometry with the alkylated base displaced into the major groove of the DNA in contrast to O6-alkylguanine:T and O4-alkylthymine:G base pairs which retain the Watson-Crick alignment with N1 of the purine juxtaposed to N3 of the pyrimidine. Measurement of the rate of repair of these different base pairs suggests that pairs with the alkyl group exposed in the major groove may be repaired more rapidly than those with the alkyl group more deeply buried in the helix.

32P-Labelled self-complementary oligonucleotides containing O6-methylguanine, O6-ethylguanine, and O4-methylthymine have been synthesized and used as substrates for the DNA repair protein O6-alkylguanine-DNA alkyltransferase (AAT). The reaction was second-order with rate constants of 2.6 X 10(7) M-1 sec-1 for O6-methylguanine, 2.6 X 10(4) M-1 sec-1 for O6-ethylguanine and 2.5 X 10(3) M-1 sec-1 for O4-methylthymine. These oligomers should allow sensitive and specific assay of the mammalian enzyme.

Structural features of pyrimidine.pyrimidine mismatches in the interior of oligonucleotide duplexes have been investigated by high resolution two-dimensional proton nuclear magnetic resonance (n.m.r.) spectroscopy. These studies were conducted on the self-complementary d(C-G-C-T-A-G-C-T-T-G-C-G) duplex (designated T.T 12-mer) and the self-complementary d(C-G-C-C-A-G-C-T-C-G-C-G) duplex (designated C.C 12-mer) containing T.T and C.C pairs located at identical positions four base-pairs from either end of the duplex. Proton n.m.r. studies on the T.T 12-mer duplex were undertaken in the neutral pH range, while studies on the C.C 12-mer duplex were recorded at acidic pH. The proton spectra narrowed considerably on lowering the pH below neutrality for the C.C 12-mer duplex. Two-dimensional nuclear Overhauser enhancement spectroscopy (NOESY) data sets have been recorded on the T.T 12-mer and C.C 12-mer duplexes in high salt H2O and D2O solution. The magnitude of the NOE crosspeaks and the directionality of the NOE connectivities demonstrate that both duplexes are right-handed with all bases, including those at the mismatch site, adopting an anti configuration about the glycosidic bond. The observed base and sugar proton chemical shifts suggest structural similarities for the trinucleotide segments centered about the T.T and C.C mismatches. A NOE is detected between the resolved imino protons of T4 and T9 at the mismatch site, consistent with formation of a stacked "wobble" T4(anti).T9(anti) pair in the T.T 12-mer duplex. A comparison of the imino proton chemical shift and NOE data suggests that the imino-carbonyl hydrogen bonds in the wobble T.T mismatch are weaker than the corresponding imino-carbonyl hydrogen bonds in the wobble G.T mismatch. The 4-amino protons of C4 and C9 at the mismatch site in the C.C 12-mer duplex do not exhibit the pattern of hydrogen-bonded and exposed protons separated by approximately 1.5 parts per million characteristic of cytidine amino protons involved in Watson-Crick G.C pairing. The experimental data are insufficient to differentiate between wobble C(anti).C+(anti) and other pairing possibilities for the mismatch in the C.C 12-mer duplex at acidic pH.

N-Nitrosamines are generated by the photolysis of neutral aqueous solutions of nitrite salts and heterocyclic amines. With nitrate salts, photolysis produces a mixture of N-nitrosamines and N-nitramines. The reactions occur with low (5 mmol/l) reagent concentrations under very mild conditions and are faster than the concurrent decomposition of N-nitrosamines and N-nitramines by photolysis. Furthermore, both N-nitrosamines and N-nitramines effect transnitrosation reactions under mild neutral conditions when photolysed in the presence of other amines.