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91.
Transjugular intrahepatic portosystemic shunt (TIPSS) is a promising method of treatment for gastric or esophageal variceal bleeding. This study was performed to determine the prognostic factors contributing to the survival of patients after TIPSS for gastric or esophageal variceal bleeding. One hundred and fifty-five patients who underwent TIPSS between September 1991 and March 2001 were followed up by clinical examination, upper gastrointestinal endoscopy, and Duplex sonography. The mean portohepatic pressure gradient prior to TIPSS was 20.5+/-9.93 mmHg and dropped to 10.7+/-6.62 mmHg after TIPSS (p<0.001). The cumulative survival rate was 75.1% at 6 months, 66.6% at 1 yr, 58.4% at 2 yr, and 38.1% at 5 yr. Survival after TIPSS was inversely related to the Child-Pugh classification (p<0.05). The rebleeding rate was 18.3% at 6 months, 21.0% at 1 yr, 32.8% at 2 yr, and 53.1% at 5 yr. The causes of deaths were hepatic failure (53.5%), recurrent variceal bleeding (11.6%), pneumonia (4.6%), sepsis (3.5%), hepatic encephalopathy (2.3%), and unknown (17.4%). Multivariate analysis (Cox proportional hazard model) revealed that the Child-Pugh classification and age were statistically significant independent prognostic factors. In conclusion, TIPSS is an effective method of treatment for variceal bleeding in cases where other treatment modalities including endoscopic therapy are unsuccessful and the most important prognostic factors are preprocedural hepatic reserve (Child-Pugh class) and age.  相似文献   
92.
Salmonella enterica subsp. enterica serovar Gallinarum (S. gallinarum) is the agent of fowl typhoid, and the 9R vaccine is a commercially available, live vaccine for the prevention of fowl typhoid. The aim of this study was to assess the safety and efficacy of the 9R vaccine in young chickens. The mean weights of 5-week-old chickens vaccinated with one and 10 doses at 2 weeks old were 450.3+/-33.83 g and 446.8+/-35.68 g, respectively, which were statistically lower (P<0.05) than the mean weight (475.5+/-44.17 g) of the control group. Using the same procedure, the mean weights of chickens vaccinated with one and 10 doses at the age of 4 and 6 weeks were 721.3+/-64.03 g and 723.7+/-63.92 g, and 1114.2+/-92.21 g and 1078.27+/-68.93 g, respectively. Compared with the mean weights (725.7+/-49.50 g and 1104.3+/-92.34 g, respectively) of the control groups, there was no difference in terms of statistical significance (P < 0.05). In addition, all vaccinated birds showed no clinical signs and survived the time course of the experiment. When all chickens were challenged with the wild-type S. gallinarum 21 days after one-dose vaccination, the mortalities between the vaccinated group and the control group were 0% to 5% and 95% to 100%, respectively. In addition, the control group demonstrated a 95% to 100% re-isolation rate of the challenge strain in internal organs and the caecum, while in the vaccinated group only a 1% to 60% re-isolation rate was observed. In this study, we showed that adjusting the minimum vaccination age of the 9R vaccine to 4 weeks is acceptable considering the safety and efficacy of the vaccine.  相似文献   
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用人Ⅳ型胶原蛋白免疫BALB/c小鼠,克隆了一组分泌抗人Ⅳ型胶原蛋白的杂交瘤细胞株,并且对其中的A2、A4、A5、B3和E2进行了鉴定。其抗体亚类分别为IgG1、IgG2、IgG2b、IgG2和IgG1。其亲和力常数Kaff=6.6×108M(-1)~6.0×10(10)M(-1)。它们均能特异性地识别人Ⅳ型胶原蛋白。  相似文献   
95.
An ELISA for the detection of mumps virus-specific IgG and IgM antibodies was developed. Three different antigen preparations were compared. Equally good results were obtained with virus concentrated by ultracentrifugation and with virus that was further purified by sucrose gradient centrifugation. Crude infected allantoic fluid was unsuitable for use as antigen. The variability and reproducibility of the tests were satisfactory. When the ELISA was compared to conventional serological methods, a good correlation of IgG absorbance values with complement fixation (CF) antibody titers was found (r = 0.574), the ELISA being more sensitive in detecting antibodies in acute-phase sera. For the determination of immunity, ELISA IgG values were compared with results obtained in hemagglutination-inhibition (HI) and hemolysis-in-gel (HIG) tests. Again there was a good correlation with both tests (rHI = 0.528, rHIG = 0.667). The ELISA was more sensitive than the HI and HIG test for the detection of low levels of antibodies.  相似文献   
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Summary Optic fibers of retinal origin terminate in the lateral geniculate body exclusively in the so called glomerular synapses. They can be recognized on the basis of their unusually large irregular mitochondria having very few cristae. In the cat the structure of the optic terminal profiles is rather dense. The majority of terminals in most glomeruli originate from axons of other source. Relatively large axon terminal profiles of unusually light structure cannot be brought to degeneration by any interference with extraneous pathways. From Golgi information it becomes obvious that they originate from local Golgi 2nd type neurons. Small rather dense axonal profiles of the glomeruli can occasionally be traced back by degeneration to the occipital cortex (parastriate), although most of the descending cortical afferents of the lateral geniculate body terminate outside the glomeruli on more proximal parts of the dendrites. — Axo-axonic synapses are very frequent. If an optic terminal is involved, it appears that by structural standards it is presynaptic to the non optic. As judged, however, from the numerous axoaxonic contacts persisting after enucleation, many of the contacts are established between non optic axon terminals. — The progress of secondary degeneration and particularly the removal from the glomeruli of degeneration fragments is unexpectedly rapid. — The possible functional significance of these findings, especially also with regards to presynaptic inhibition, is discussed.  相似文献   
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100.
AIMS: To develop an alternative assay for specific genotyping of the -alpha(4.2) thalassaemia deletion based on the DNA sequence features surrounding the breakpoint. METHODS: The 5' and 3' ends of the breakpoint regions of the -alpha(4.2) allele and the normal homologous segments were sequenced in Chinese individuals. A sequence haplotype composed of four single nucleotide variations within the X2/X1 box of the -alpha(4.2) breakpoint region was found in all of the 10 Chinese -alpha(4.2) thalassaemia alleles studied. Based on these findings, a novel polymerase chain reaction (PCR)/denaturing high performance liquid chromatography (DHPLC) assay was developed for rapid genotyping of the -alpha(4.2) allele instead of traditional Southern blotting or Gap-PCR. This method involves amplification of the alpha globin target sequence encompassing these four polymorphic sites, followed by a partially denaturing HPLC analysis using the transgenomic WAVE DNA fragment analysis system. RESULTS: The three major genotypes (-alpha4.2/alphaalpha, -alpha(4.2)/--SEA, and alphaalpha/alphaalpha) could be distinguished through the characteristic chromatograms generated by the WAVE system. The accuracy of this technique was evaluated blindly, and the results were 100% (40 of 40) concordant with the genotypes previously characterised by Southern blotting or Gap-PCR. CONCLUSIONS: This study validates the PCR/DHPLC approach as a simple, rapid, highly accurate, and cost effective method, potentially adaptable for use in epidemiological surveys, genetic screening, and diagnosis of silent alpha+ thalassaemia and Hb H disease.  相似文献   
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