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31.
The polymerase chain reaction (PCR) was used to detect varicella zoster virus (VZV) DNA in vesicle samples from patients with varicella and zoster. Primers and the oligonucleotide probe were chosen from the region of the immediate early gene 63. Procedures for preparing the DNA from the specimens were omitted, and the amplified DNA was directly detected in ethidium bromide-stained polyacrylamide or agarose gels, thus providing a rapid and less laborious assay. A total of 66 vesicle specimens including 3 crusts (collected on days 1-14 after the onset of exanthem) were tested by the simplified VZV-PCR, and 64 (97%) were positive. When the direct visualization of the amplified DNA was confirmed by DNA hybridization, a non-radioactive hybridization assay involving a digoxigenin-labelled oligonucleotide probe and detection by chemiluminescence proved as adequate as a radioactive hybridization assay. Thus, the VZV PCR described appears to be a useful diagnostic test for detecting and identifying varicella zoster virus.  相似文献   
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Extended -spectrum β -lactamases(ESBLs)aremainlyproducedbymembersofthefamilyEnter obacteriaceaewhichcanhydrolyzeβ -lactamantibi oticsincludingthethird - generationcephalosporinandaztreonam ,theESBLs- producingbacillishowedmedian -highresistancetoceftazidimeandaztreonamparticularly[1] .NowadaystheprevalenceofESBLs -producingstrainshavebeenreportedinmanyareasaroundtheworld[2 ] .ButthereisfewinformationabouttherelationshipbetweentheuseofantibioticandtheproductionofESBLs .Weperformedastud…  相似文献   
33.
OBJECTIVE: This study was undertaken in order to determine the risk factors for pregnancies complicated by placental abruption in a socio-economically disadvantaged region in metropolitan Adelaide. METHODS: This was a retrospective case-control study including all singleton pregnancies resulting in placental abruption between 2001 and 2005. RESULTS: The overall incidence of placental abruption was 1.0%; the overall perinatal mortality among the births with abruption was 13%. Univariate analyses showed the following significant risk factors for placental abruption: preterm pre-labor rupture of the membranes (PRE-PROM; odds ratio (OR) 4.79, 95% confidence interval (CI) 1.52-15.08), non-compliance with antenatal care (OR 2.93, 95% CI 1.06-8.90), severe intrauterine growth restriction (IUGR), and elevated homocysteine levels (OR 45.55, 95% CI 7.05-458.93). Severe IUGR was significantly more common in the abruption group compared with the control group (p = 0.032). In the multivariate analysis, PRE-PROM remained a significant independent risk factor for placental abruption. Marijuana use, domestic violence, and mental health problems were more common (borderline significance) in the abruption group. Smoking and preeclampsia were not found to be associated with placental abruption in this study. CONCLUSIONS: In this high-risk population, PRE-PROM and elevated homocysteine levels appear to represent the major risk factors for placental abruption.  相似文献   
34.
The frequency of recombination between the G gamma-globin (HBG2) and parathyroid hormone (PTH) loci on the short arm of human chromosome 11 was estimated by typing greater than 700 single-sperm samples from two males. The sperm-typing technique employed involves the polymerase chain reaction and allele-specific oligonucleotide hybridization. Our maximum likelihood recombination fraction estimate of 0.16 (95%) confidence interval, 0.13-0.19) falls well within previous estimates based on family studies. With current technology and a sample size of 1000 sperm, recombination fractions down to approximately 0.009 can be estimated with statistical reliability; with a sample size of 5000 sperm, this value drops to about 0.004. Reasonable technological improvements could result in the detection of recombination frequencies less than 0.001.  相似文献   
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V Lange 《Endoscopy》1986,18(5):195-196
Gastric bezoars, especially those of the phytobezoar type, are a rare sequela of gastroduodenal surgery or other uncommon circumstances. When they produce symptoms, removal is always necessary. In the past, treatment has shifted from surgical to non-surgical intervention, of which gastric lavage and/or slow enzymatic dissolution have been attempted. A safe, simple and rapid endoscopic method for the removal of the bezoar has previously been reported by 3 authors. With our two patients there are now ten cases of successful fragmentation of phytobezoars by this technique using a pulsating jet of water through the endoscope. This success recommends the procedure as treatment of choice, and it should be used more widely.  相似文献   
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W R Bezwoda  J D Esser  R Dansey  I Kessel  M Lange 《Cancer》1991,68(4):867-872
Four hundred fifteen patients with metastatic breast cancer with known hormone receptor status received primary treatment with tamoxifen. Measured values for the estrogen receptor (ER, i.e., with estrogen binding) followed a continuous distribution (range, 3 to 1000 fmol/mg of protein). These values correlated positively with age. The response to treatment with tamoxifen correlated with the ER level, with response rates of approximately 80% when the ER level was greater than 30.1 fmol/mg of protein. Two hundred eighteen (218 of 415, 52%) patients had progesterone receptor (PR) values greater than 10 fmol/mg. The PR positivity correlated with the ER level. Patients with PR levels greater than 10 fmol/mg of protein (124 of 226, 55%) had a significantly higher response rate than those with values less than 10 fmol/mg of protein (45 of 189, 24%). However, in a multivariate analysis including both receptor levels, age, site, and number of metastases, only the ER level was significant in predicting the response to treatment with tamoxifen. A quantitative estimation of the ER level thus is the best predictor of response to hormonal treatment with tamoxifen for advanced breast cancer.  相似文献   
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