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To study the effects of bepridil on the rapidly activating component (IKr), the slowly activating component (IKs) of the delayed rectifier potassium current and the inward rectifier potassium current (IK1) in hypertrophied guinea pig ventricular myocytes.The whole cell patch clamp techniques were used.In hypertrophied guinea pig ventricular myocytes, bepridil 30 mumol.L-1 markedly inhibited IKr and IKs (by 20.9% and 27.2% at 0 mV and mV, respectively). The effect of bepridil on IKs was larger than on IKr. Bepridil 30 mumol.L-1 also significantly inhibited the inward component of IK1 (by 15.1% at +100 mV), but the reverse potential of IK1 was unaffected. Bepridil (1-100 mumol.L-1) was shown to inhibit IKr and IKs in a concentration-dependent manner. Their IC50 were 46.7 mumol.L-1 and 23.8 mumol.L-1, respectively.Bepridil inhibit IKr, IKs and IK1 in hypertrophied guinea pig ventricular myocytes, which may be important in understanding the antiarrhythmic effects of this drug.

A method for the separation and analysis of the chiral pseudoephedrine enantiomers using capillary electrophoresis was established. The buffer solution for separation was 25 mmol/L Tris-phosphate, including 38 mmol/L hydropropyl-beta-cyclodextrin with pH value of 2.65. (1S, 2S)(+) Pseudoephedrine in Bufferin Cold tablet was determined. The method has good precision, recovery and linear relationship.

This paper presents the strategy, methodology and results of virtual prototyping-based thermo-mechanical design and qualification methods, developed by Philips together with its technology partners. The results of virtual thermomechanical prototyping can be used to predict, evaluate and optimise the thermal and mechanical behavior of electronic packages against the actual packaging requirements prior to major physical prototyping and manufacturing investments. The presented results show that the development and application of the virtual prototyping method can make substantial contribution to the sustainable business profitability of the electronics industry. The industrial feasibility and added values of virtual prototyping-based thermo-mechanical design and qualification methods largely depend on, among other aspects, the advanced methodologies and technologies used to characterize and model the process dependent thermomechanical properties of packaging materials. Process dependencies are related to the production history as well as to the subsequent thermo-mechanical loading (time, temperature, stress level, geometry, damage evolution, etc.). Therefore, the present paper presents our investigation results on the state of the art, the bottlenecks and the innovative solutions for material characterization and modeling, focusing on solder and polymer materials and taking into account the needs for future electronic packages. The experimental and modeling results presented in this paper demonstrate that by integrating the proposed innovative solutions for material characterization and modeling with the virtual thermo-mechanical prototyping methods, competitive packaging development can be achieved.

Background: Therapy of atrial fibrillation by electrical cardioversion (CV) is limited by the high rate of recurrences. Early recurrence of atrial fibrillation (ERAF) occurs in a subgroup of patients whose characteristics are poorly defined. This prospective study was performed to evaluate if the P wave signal-averaged ECG (PSAECG) is able to identify patients with an increased risk of ERAF after CV. Methods: Patients with an indication for elective external CV were enrolled. After successful CV, PSAECGs were recorded at 0.5, 1, 24 h and 1 week. The ability of PSAECG parameters (signal-averaged P wave duration, PWD; root-mean-square of the voltage of the terminal 20, 30, and 40 ms of the signal-averaged P wave; RMS20, RMS30, RMS40) to predict ERAF (prospectively defined as AF recurrence within 4 h after CV) was assessed. Results: Of 111 consecutive patients, 7 experienced ERAF, 30 patients had AF recurrence later during the 1-week follow-up. Patients with ERAF had a significantly prolonged signal-averaged PWD compared to patients who remained in SR (194±16 ms vs 139±3 ms at 0.5 h, p

The dynamical fusion process of 48Ca + 144Sm with different impact parameters near barrier is studied by an extended quantum molecular dynamics (EQMD) model, where width of wavepacket is dynamically treated based on variational principle. The time evolution of different energy components such as potential energy, kinetic energy, Coulomb energy and Pauli potential are analyzed when dynamical or fixed width is assumed in calculation. It is found that the dynamical wavepacket width can enhance the dissipation of incident energy and the fluctuations, which are important to form compound nuclei. Moreover, we compare the fusion barrier dependence on the incident energy when it is determined by both dynamical and fixed wavepacket width.

To study the effects of puerarin (Pue) on IA and IK in mouse hippocampal neurons.The whole cell patch clamp techniques were used.Pue reduced the amplitude of IA and IK, in a concentration-dependent, but not rate- or use-dependent manner (IC50 were 461 micromol/L and 215 micromol/L, respectively). Pue (0.5 mmol/L) shifted the steady state activation curves of IA and IK to positive and negative potentials (Vh about 20.6 mV and 28.6 mV) respectively, but inactivation curves of IA were not affected by Pue.Pue inhibited IA and IK in mouse hippocampal CA1 neurons and its blocking effect on I(K) was much stronger than on IA.

To elucidate possible ionic mechanisms of antimyocardial ischemia and antiarrythmia of tetramethyl pyrazine (TP), we studied L-type Ca2+ currents (I(Ca.L)) in adult rat ventricular myocytes using the whole-cell patch-clamp technique. The results showed: (i) under physiological conditions, 0.25 mmol/L TP decreased amplitude of I(Ca.L) to 60.6% and this inhibition was increased with increasing concentration of TP. ID50 was 0.20 mmol/L. (ii) The Ca2+-antagonistic effect of TP was voltage-dependent. A marked negative shift of the steady-state inactivation curve was observed with long (10 s) conditioning prepulses, but not with short (350 ms) ones. (iii) The time course of inhibition during TP treatment was increased with an increase in drug concentration, and recovery from TP-induced inactivation of I(Ca.L) was slower than in control cases. (iv) Tonic block and use-dependent block with TP treatment, which was induced by increasing the frequency of stimulation, occurred. We suggest that TP inhibits the I(Ca.L) mainly by binding to inactivated Ca2+ channels. The high affinity of TP for the inactivated state of I(Ca.L) may play an important role in developing therapies for pathological conditions.

Signal averaging techniques are used for detection of low amplitude, high frequency signals in the surface ECG. P-wave signal-averaging has been used to predict the risk for development of atrial tachyarrhythmias in patients with structural heart disease. There is, however, a lack of prospective studies evaluating normal values of the P-wave signal-averaged ECG in healthy individuals. Moreover, day-to-day reproducibility of results of P-wave signal-averaging is not precisely known. Thus, the aim of this study was to determine normal values and reproducibility of time-domain P-wave signal-averaging in a large cohort of healthy volunteers. A commercially available device (MAC 5000, Marquette Hellige) was used for signal-averaging. A vector magnitude was calculated from Frank's orthogonal leads after P-waves were sampled and filtered with a spectral filter using fast fourier transform. We examined 123 volunteers without cardiovascular disease at two occasions. Mean P-wave duration was 114 +/- 13 ms for the overall study population. There was a slight but statistically significant increase in filtered P-wave duration with age (r = 0.32, p0.001). All values were reliably reproducible upon the second examination (r = 0.624 to 0.706, p0.0001). These results may serve as a future reference to other studies examining patients with structural heart disease.

We present a case of an anomalous pancreaticobiliary junction (a long common channel) that was clearly demonstrated by extraductal ultrasonography with a transduodenoscopic miniprobe placed in the duodenal lumen. The present case suggests a potential indication for the ultrasound miniprobe, in extraductal ultrasonography, in the pancreatobiliary region. In this method, the position of a miniprobe can readily be adjusted under endoscopic guidance, unlike ordinary endoscopic ultrasonography.

This paper presents some of our recent research and development results for virtual thermo-mechanical prototyping of electronic packages. Philips’ simulation-based optimization strategy focusing on the development of reliable Response Surface Models for the underlying nonlinear responses is demonstrated. This strategy plays a vital role in the realization of virtual thermo-mechanical prototyping of electronic packages. The demonstrator presented in this paper shows that combining reliable nonlinear FEM-based simulation models with this optimization strategy is an effective and efficient method for virtual thermo-mechanical prototyping of electronic packages.

A capillary zone electrophoresis method was set up for the separation and determination of glycyrrhizin in Chinese medicinal preparations. Concentrations of Na(2)B(4)O(7) were optimized, which showed that glycyrrhizin in the sample could be separated from interference in the running buffer of 30 mmol/L Na(2)B(4)O(7). Using declofenac as internal standard, the simple method was linear in the range 25-300 microg/mL of glycyrrhizin, and good reproducibility was obtained. The extracts of Radix glycyrrhizae and its preparations could be injected directly for analysis without any pretreatment.

Tetrahydropalmatine in Rhizoma corydalis and its preparations were separated and determined with no pretreatment in the buffer solution of 50 mmol/L of sodium acetate in methanol containing 2 mol/L acetic acid.

To study the effects of doxepin (Dox) on cerebral artery.The effects of Dox were observed using the isolated basilar and saphenous artery rings of rabbits.Dox inhibited the constriction of the basilar and saphenous artery rings evoked by KCl with IC50 5.75 mumol.L-1 (95% confidence limits were 2.3-14 mumol.L-1, n = 8) and 34.6 mumol.L-1 (95% confidence limits were 3.8-316 mumol.L-1, n = 8), respectively. Dox also inhibited the constriction of the basilar and saphenous artery rings of the rabbits stimulated by 5-hydroxytryptamine (5-HT), IC50 were 6.3 mumol.L-1 (95% confidence limits were 1.7-23.3 mumol.L-1, n = 7) and 8.0 mumol.L-1 (95% confidence limits were 6.3-10.3 mumol.L-1, n = 6), respectively. In both samples (basilar and saphenous artery rings) CaCl2 evoked, the pD2 of Dox was 5.28 +/- 0.40 and 4.76 +/- 0.14, respectively (n = 6, P0.01). Dox 5.8 mumol.L-1 inhibited the constriction of the saphenous artery evoked by norepinephrine (NE) in Ca(2+)-free medium. Dox 30 mumol.L-1 inhibited the constriction of the saphenous artery evoked both by NE and by readmission of CaCl2 (1.25 mmol.L-1).As compared with its effect on the saphenous artery, Dox selectively inhibited the basilar artery.

A surfactant-assisted ball milling technique was employed to synthesize NdFeB nanoparticles and nanoflakes from melt-spun nanocrystalline powders. The microstructure evolution during ball milling and the particle size dependent magnetic properties were investigated. The formation mechanism of submicrometre flakes and textured nanoflakes were discussed. The surfactant and ball-to-powder weight ratio played a crucial role in the formation of nanoflakes. The coercivity of the particles decreased with decreasing particle size. Significant room temperature coercivity HC higher than 300 kA m−1 was obtained in the nanoparticles with a mean size of ~20 nm. The spin reorientation temperature was found to decrease with reducing particle size, which may be related to the change in magnetocrystalline anisotropy caused by the induced strain during ball milling.

A serological study on the detection of HBV and HCV infection markers and the investigation of related sexual behaviors were conducted among 431 female prostitutes and 109 normal women. The result showed of anti-HBc prevalence rate was 43.1% (186/431), anti-HBs positive rate was 36.9% (159/431), HBsAg positive rate was 11.1% (48/431) and anti-HCV positive rate 9.51% (41/431). They were all significantly higher in prostitutes than in normal women. The infection indexes of HBV and HCV were also higher in population with STD than in normal women. The prevalence of anti-HCV in female prostitutes tended to increase with increase of age. There was a significant correlation with the number of their clients and years of being prostitutes. This demonstrated that there was a relatively high HBV and HCV infection rates in prostitutes.

An optimum procedure was established by orthogonal test for preparing cis-platin albumin microspheres (CDDP-AMS) with emulsion-heating stabilization method. The factors which affect particle size and release rate in vitro were studied. The particle size focusing on 58.8-256 microns, the mean size was 148.46 microns, drug content was 51.16% (w/w). The dissolution profiles of the CDDP-AMS followed Higuchi kinetics. In rabbits the distribution and elimination half times of platinum were prolonged 3.36 times and 1.23 times vs injection group, respectively, after hepatic arterial chemoembolization with CDDP-AMS. The highest serum concentration of platinum is 30 percent of that of the injection group. The platinum concentration was increased in liver (P0.01) and decreased in kidney (P0.05) vs that of injection group.

The neurobehavioral status was tested for 92 matched-pair pupils aged 11-13 in an area with high-level-manganese sewage irrigation and a control area. Results showed there was significant difference in manganese contents of drinking water between the area with sewage irrigation and the control area during 1990-1992, ranged 0.241-0.346 mg/L and 0.030-0.040 mg/L, respectively, with P0.01. Hair manganese content of children in the area with sewage irrigation (1.252 micrograms/g) was significantly higher than that in the control area (0.961 micrograms/g) with P0.01. Scores in digit span, Santa Ana manual dexterity, digit symbol, Benton visual retention test and pursuit aiming test for children in the area with sewage irrigation were significantly lower than those in the control area (P0.01). Hair manganese contents of the children in the area with sewage irrigation correlated negatively with most of those scores. It suggested high level of manganese in drinking water of the area with sewage irrigation might be an important factor affecting children's neurobehavioral changes.

Hepatitis C virus (HCV) infection is one of the important causes of chronic and severe hepatitis in China. In an attempt to understand if there is any relationship between HCV infection and glomerulonephritis (GN), serum samples from 570 GN patients and 100 normal volunteers were screened for anti-HCV antibody (HCV-Ab) with ELISA method. Among the cases with positive HCV-Ab, serum HCV-RNA was tested with nested RT-PCR method. The incidence of serum HCV-Ab was 2 in 100 normal volunteers (2%) and 34 in 570 GN patients (6%). The incidence of positive serum HCV-RNA was 0 in normal volunteers whereas 21 in GN patients. The main clinical manifestation of GN patients with serum positive HCV-Ab was an unique proteinuria with/without nephrotic syndrome or renal failure, whereas the pathologic lesions in GN patients with serum positive HCV-Ab or HCV-RNA consisted of different disease entities. There was no close link between MPGN and active HCV infection. From the data observed, it seems that there is a coincidence between glomerular diseases and HCV infection rather than a matter of cause and consequence.

We amplificated a HBV DNA fragment coding the major HBsAg from a chronic HBsAg carrier's serum with high titer of HBsAg and anti-HBs using polymerase chain reaction (PCR). The direct sequencing of PCR products revealed a single mutation from adnosine to guanosine at the nucleotide position 532 of HBV DNA of the escape mutant. This mutation might result in an amino acid substitution from threonine to alanime at the amino acid position 126 of HBsAg. Since this amino acid is located in the first loop of the "a" determinant of HBsAg, the mutation might result in an alteration of the structural antigenicity of the "a" determinant and induce escape mutant of HBV.

A series of orthorhombic manganites Gd(1-x)Ho(x)MnO(3) (0

The effect of nonmagnetic Y partial substitution at the Dy site in Dy(1-x)Y(x)MnO(3) up to x=0.2 on magnetism, specific heat, and ferroelectricity is investigated, which resulted in a preliminary multiferroic phase diagram. It is revealed that the Y partial substitution suppresses the Dy-spin ordering point (T(Dy)) and ferroelectric ordering point (T(FE)) but enhances the Mn-spin ordering point (T(N)). The interaction between the spins of Dy and Mn is remarkably affected by Y substitution. The measured electrical polarization depends on the Y substitution in a complex way because the ferroelectricity is sensitive to the interaction between the spins of Dy and Mn. (c) 2011 American Institute of Physics. [doi: 10.1063/1.3536506]

Air electrodes, made with a mixture of carbon nanotube (CNT)/carbon nanofiber (CNF) and with/without α-MnO2 nano-rods, were prepared for Li-air cells. The charge capacity and cyclability were found to increase largely for the cells made with the α-MnO2 catalyst; however, the first cycle discharge capacities were no different for the cells made with and without the α-MnO2 catalyst. It was found that the discharge capacity of the Li-air cell was mainly due to oxygen deficiency from the pinch-off of the diffusion channel by the deposition product at the air side of the air electrode. Electrochemical impedance spectra at different cycles demonstrated that the charge transfer resistance was increased and decreased during discharge and charge processes, respectively, due to the change of porosity, oxygen concentration, and rate of coefficient of chemical reaction in the air electrode.

In order to investigate the prevalence of different types of viral hepatitis in Beijing area, the markers of viral hepatitis A, B, C and E were detected on 72 adult patients with acute viral hepatitis in the infectious diseases department of our hospital. The results showed that 26.4% of the cases had HAV infection, 8.3% HBV infection, 18.1% HCV infection and 31.9% HEV infection. It is shown that the prevalence of HEV infection in Beijing area is high.

Li-air cells based on Li foil as an anode electrode, freestanding carbon nanotube/nanofiber mixed buckypaper as an air (cathode) electrode, and organic electrolyte were assembled. The air electrode was made with single-wall carbon nanotube (SWNT) and carbon nanofiber (CNF) without any binder. The discharge capacity was strongly dependent on both the discharge current density and the thickness of the air electrode. A discharge capacity as high as 2500 mAh/g was obtained for an air electrode at a thickness of 20 μm with a discharge current density of 0.1 mA/cm 2 ; however, it was reduced to 400 mAh/g when the thickness of the air electrode was increased to 220 μm. For a 66 μm thick air electrode, the discharge capacity decreased from 1600 to 340 mAh/g when the discharge current density increased from 0.1 to 0.5 mA/cm 2 . The scanning electron microscope images on surfaces of the air electrode from a fully discharged cell showed that the voids at the air side were almost fully filled by the solid deposition; however, the voids at the membrane side were still wide open.

Tetramethylpyrazine (TMP) inhibited the contraction of rabbit basilar artery and mesenteric arteries caused by KCl with an IC50 of 1.3 mmol.L-1 and 7.5 mmol.L-1 (P0.01). The contraction of the rabbit basilar and mesenteric artery ring evoked by KCl, CaCl2 and norepinephrine was inhibited noncompetitively by TMP with the pD2' values of 2.18 +/- 0.16 and 1.83 +/- 0.18 (P0.01), 2.13 +/- 0.12 and 2.08 +/- 0.12 (P0.05), 3.08 +/- 0.16 and 2.57 +/- 0.08 (P0.01), respectively. The contraction of rabbit basilar artery and saphenous veins evoked by 5-HT was also inhibited by TMP with an IC50 of 0.22 mmol.L-1 and 2.2 mmol.L-1 (P0.01), respectively. TMP antagonized the myogenic activity of rat portal vein strips. TMP increased canine vertebroarterial blood flow and had no effect on femoral artery blood pressure. The results suggested that TMP may block the calcium channel, inhibit the contraction of rabbit basilar artery, and improve the canine vertebroarterial circulation selectively.

Imipramine (Imi) inhibited the contractile response to BAY k 8644 (IC50 = 2.39 +/- 0.33 mumol.L-1), KCl (IC50 = 1.00 +/- 0.09 mumol.L-1), in rabbit basilar artery rings. Imi was more effective in suppressing the contractile response evoked by KCl, CaCl2, and 5-HT in basilar artery rings than in mesenteric artery rings. The effect of Imi was the same as that of diltiazem (Dil). There was no difference between the inhibitory response of Imi on contraction induced by KCl in basilar artery rings with or without endothelium. The results suggest that Imi may block the calcium channel and inhibit the rabbit basilar artery selectively, and the effect is endothelium-independent.

Effects of trihexyphenidyl (THP) were examined on the slow action potentials (SAP) induced by isoproterenol (Iso), histamine (His), Bay k 8644 or tetrodotoxin (TTX), in guinea pig papillary muscles. THP 10, 50, and 100 mumol.L-1 depressed the maximal upstroke velocity (Vmax) and the action potential amplitude (APA) of SAP. These effects were reversed partially by the elevation of the concentration of calcium from 2.0 to 5.6 mmol.L-1. The results suggest that THP can inhibit calcium inflow in myocardium.

Plasma levels of RU 486 and its metabolites, RU 42633, RU 42643, and RU 42698 were determined by HPLC in nonpregnant (n = 9) and early pregnant (n = 36) women orally administered with different doses of RU 486. The results showed that absorption and initiation of metabolism of RU 486 were rapid in both groups, as indicated by the fact that RU 486 and its 3 metabolites could be measured in plasma 20 minutes after administration and that Tmax of RU 486 was between 1 and 2 hours. There was a positive correlation (p 0.01) between the logarithm of Cmax and that of the corresponding doses orally administered in each group. The plasma drug-time curve of each dose in the nonpregnant group was higher than that in the pregnant group, and so was the AUC. However, there was no significant difference in these 2 parameters between the 2 groups (p 0.05). Metabolism of Ru 486 was in agreement with 2-compartment open models after oral administration of 25 mg, 100 mg, and 200 mg, and presented as a process of nonlinear kinetics after the intake of 400 mg and 600 mg in both pregnant and nonpregnant women. (author's modified)

In order to explore the relationship between the different location of myocardial infarction (MI) and reflections of pathognomonic Q potentials on the body surface, an experimental study was carried out in 28 dogs. The results were (1) in 27 of a total 28 dogs after MI formation, abnormal Q maps appeared; (2) right ventricular MI, posterior wall MI and some lateral and apical MI are prone to miss abnormal Q potentials in the conventional 12-lead ECG; and (3) the MI location and relative size diagnosed through electrocardiographic peak mapping (EPM) correlated to acute MI in dog ventricles fairly well. The unexpected Q map reflections of right ventricular MI provide new clues for improving our automatic diagnosis system after further correlative studies. The results strongly support the feasibility of the application of EPM in clinical diagnosis.

The plasma concentration of RU486 and its metabolites were studied to achieve a systematic comparison of different dosages, and to investigate the pharmacokinetics of different dosages in order to determine the optimum dosage and means of administration of RU486 in clinical applications. Nine healthy women aged 22 to 35 were recruited for the study. RU486 was given orally before menstruation for 5 consecutive months in increasing dosages of 25, 100, 200, 400. and 600 mg, respectively. Blood samples were drawn 12 times at 1/3 to 120 hours following each drug administration. The HPLC method was used in the analysis, and a 200 mm x 3.5 mm ODS/YWG column was used. The mobile phase was methanol: acetonitrile: water 42:28:30 (V:V:V). The Ph level was 4.7, and the flow rate was 1 ml/min. An ultra-violet detector was used for monitoring at 302 nm. Under these chromatographic conditions, RU486 and its metabolites were well separated. The plasma concentration of the four compounds were linear over the range of 100-2800 ng/ml. Their linear correlation coefficients were all 0.999. The recovery of different concentrations of RU486, Ru42633, and RU42698 was 90% and that of RU42848 was 60%. The HPLC chromatographic conditions and the procedures used for blood sample analysis provided a reliable method to test separation and measurement of RU486 and its metabolites in blood sample for pharmacokinetic research. The separation of RU486 and its metabolites differs in different Ph mobile phases. A Ph level of 4.7 seems to lead to optimum separation.

Trihexyphenidyl (Tri) inhibited the contraction of rabbit basilar artery due to high K+ (45.6 mmol/L). IC50 was 2.9 +/- 0.7 mumol/L. The contractions of basilar and mesenteric arteries due to calcium and those of basilar artery and saphenous vein due to serotonin were noncompetitively. Tri inhibited myogenic activities of the portal vein strips of rats and increased the normal cerebral blood flow of rats to 19 +/- 7 ml/(min.100 g).

The lateral growth rates observed during the Kr + laser-induced deposition of W spots from gaseous mixtures of WF 6 and H 2 have been analyzed on the basis of model calculations for pyrolytic laser-CVD. The apparent chemical activation energies derived for substrates of fused quartz (a-SiO 2 ) covered either with 700 A of sputtered W or with 1200 A of amorphous Si (a-Si) are 30 and 40 kcal/mol, respectively.

Kr+ laser‐induced pyrolytic direct writing of W stripes by H2 reduction of WF6 has been investigated. The reproducibility of the process and the morphology and electrical properties of deposits depend heavily on the partial pressures of both WF6 and H2; the best results have been obtained with p(WF6)=5 mbar and 100 mbar≤p(H2)≤800 mbar. For a laser focus of 2w0=7 μm and laser powers between 30 and 200 mW, the widths of stripes varied between 1.5 and 15 μm with corresponding thicknesses between 0.1 to 3 μm. The width of stripes is independent of the scanning speed within the range 20 μm/s≤Vs ≤400 μm/s. The electrical resistivities of these stripes were about a factor of 1.3–2.3 larger than the bulk value.

Materials processing with lasers in a chemically reactive atmosphere (LCP) is a new and interdisciplinary field. The technique permits maskless single-step patterning of materials by deposition, surface modification, synthesis and etching [1,2]. The lateral dimensions of the processed regions range from several centimeters to less than one micrometer. Contrary to conventional techniques such as chemical vapor deposition (CVD), plasma deposition (PCVD) or plasma etching (PE), reactive ion sputtering (RIE) etc., LCP is not limited to planar substrates, but allows three dimensional fabrication as well.