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101.
Nucleotide 6724 of the factor VIII gene harbors a polymorphism of low frequency. A report from Taiwan claimed that 97.9% of the 83 alleles examined were of the A nucleotide at this position, which is quite different to the data from Western populations. Furthermore, this nucleotide is the start of exon 25, located in juxtaposition to the splicing acceptor of intron 24. We wonder if the nucleotide change at this location might have any effect on the splicing process of pre-mRNA. Using genomic DNA with direct sequencing of the polymerase chain reaction-amplified intron 24/exon 25 junction site, we found that 59 of the 60 patient samples were of the GTG sequence at nucleotides 6724-6726. The polymorphism is similar between populations in Taiwan and Western countries. The sequence of intron 24 around the splicing acceptor was always TCCAACTCTATTGCCCTCAG (-20 to -1), except for one hemophiliac patient who had a mutation in which the absolute consensus AG doublet of the intron 24 splicing acceptor changed to the AA dinucleotide. Owing to the mutation, exon 24 was erroneously spliced to exon 26, and exon 25 was skipped. This finding further testifies to the importance of the invariant AG dinucleotide in the example of the factor VIII gene.  相似文献   
102.
Sir, In their article, Shankar and colleagues underline the significantburden of tuberculosis within their population and the importanceof identifying latent infection  相似文献   
103.
104.
A PTH gene has been isolated from the fish Fugu rubripes. The encoded protein of 80 amino acid has the lowest homology with any of the PTH family members. Fugu PTH(1-34) had 5-fold lower potency than human PTH(1-34) in a mammalian cell system. INTRODUCTION: Parathyroid hormone (PTH) is the major hypercalcemic hormone in higher vertebrates. Fish lack parathyroid glands, but there have numerous attempts to identify and isolate PTH from fish. MATERIALS AND METHODS: Polymerase chain reaction (PCR) was performed with primers based on preliminary data from the Joint Genome Institute database. PCR amplification was performed on genomic DNA isolated from Fugu rubripes. PCR products were purified and DNA was sequenced. All sequence was confirmed from more than one independently amplified PCR product. Multiple sequence alignments were carried out, and the percentage of identities and similarities were calculated. An unrooted phylogenetic tree, using all the known PTH and PTH-related protein (PTHrP) amino acid sequences, was determined. Synthetic peptides were tested in a biological assay that measured cyclic adenosine 3',5'-monophosphate formation in UMR106.1 cells. Rabbit polyclonal antisera specific for N-terminal human PTHrP and one rabbit polyclonal antiserum specific for N terminus hPTH were used to test the cross-reactivity with fPTH(1-34) in immunoblots.  相似文献   
105.
Expression of beta-2-microglobulin by nasopharyngeal carcinoma.   总被引:1,自引:0,他引:1  
Serum beta-2-microglobulin (beta 2M) levels of 274 Chinese patients with different stages of nasopharyngeal carcinoma at presentation and that of 35 patients who developed distant metastases post-treatment were assayed. beta 2M level was found to increase with advancing stage of disease, with statistically significant differences among early-stage, advanced-stage, and metastatic disease. Elevated pre-treatment beta 2M levels were expressed more frequently by tumours with lower degree of histological differentiation. The sensitivity of serum beta 2M for diagnosis of nasopharyngeal carcinoma, however, is low.  相似文献   
106.
Chronic use of ethanol may cause a variety of immunological abnormalities in humans. In this study, we have determined the effects of an acute, low dose of ethanol (0.5 g/kg), administered either intravenously or orally, to normal, nonalcoholic male volunteers, on natural killer cell (NK) activity. We have also examined the effects of a 4-hr incubation with ethanol, in concentrations ranging from 0 to 320 mg/dl, on human NK activity in vitro. NK activity was measured by the 51Cr release assay technique in all of these studies, using peripheral blood mononuclear cells prepared from blood obtained from healthy, nonalcoholic volunteers. Eight subjects received ethanol in vivo; cells from nine subjects were used for the in vitro studies. Blood ethanol concentrations were determined at multiple time points before and after ethanol administration for the in vivo studies; for the in vitro studies, ethanol concentrations were measured from each assay sample both before and after the incubation period. Gas chromatography was used for determinations of both blood alcohol and medium ethanol concentrations. Results of the in vivo studies showed that a single dose of ethanol (0.5 g/kg), administered either intravenously (with resultant peak blood levels transiently up to 89 mg/dl) or orally (with resultant peak blood levels transiently up to 40 mg/dl at the time of the NK assay), did not alter NK activity. However, results of the in vitro studies showed a significant dose-dependent decrease ( p < 0.001) in NK activity when ethanol exposure was sustained for 4 hr at concentrations of 80 mg/ dl and above. We conclude that one of the possible causes for a higher incidence of certain viral infections and malignant tumors among chronic alcoholics may be due, in part, to this observed direct effect of ethanol on NK cytotoxicity.  相似文献   
107.
MR appearance of two patients with large, orbital conjunctival epithelium-lined inclusion cysts are presented. Both were complications of ophthalmic surgical procedures that necessitated conjunctival incision.  相似文献   
108.
目的:探讨西脉镍钛形状记忆合金环抱器用于骨折内固定术有关的护理配合问题。方法:12例不同部位骨折病人(其中男性8例、女性4例、年龄15~62岁)采用西脉镍钛(TiNi)形状记忆合金环抱器人实施内固定手术,观察术中护理配合要点和实际效果。结果:骨折复位满意,手术持续时间<2h。所有病人术后均无感染迹象,手术切口愈合良好。结论:围术期护理配合质量(如器械选择、塑形准备、无菌操作等)的优劣,是手术成功与否的重要因素之一。  相似文献   
109.
BACKGROUND/AIMS: Bamboo joint-like (BJL) appearance is an endoscopic finding characterized by swollen longitudinal folds transversed by erosive fissures or linear furrows on the lesser curvature side of gastric body and cardia. It has been reported to be associated with Crohn's disease (CD). This study was aimed to evaluate the incidence of BJL appearance in Korean patients with CD. METHODS: From January to December in 2005, we performed esophagogastroduodenoscopy (EGD) in patients diagnosed as CD and ulcerative colitis (UC) in our hospital. Non-inflammatory bowel disease (IBD) subjects with upper gastrointestinal symptoms who underwent EGD were consecutively enrolled during the same period. One endoscopist performed all the endoscopic examinations to avoid inter-observer variation. A dye-spraying technique with 0.4% indigocarmine was used to allow the detection of subtle changes during the endoscopic examination. RESULTS: A total of 21 patients with CD (mean age+/-SD, 40+/-15 yr; M/F, 13/8), 28 patients with UC (42+/-15 yr; 21/7), and 685 non-IBD subjects (49+/-14 yr; 354/331) were enrolled. EGD findings in CD patients were gastric erosions (11/21), chronic superficial gastritis (5/21), chronic atrophic gastritis (1/21), duodenal erosions or ulcers (2/21), and normal (2/21). Incidence of BJL appearance was significantly higher in patients with CD (47.6%, 10/21) than others (UC, 3.6%, 1/28; non-IBD, 0.1%, 1/685) (p< 0.0001). Among patients with CD, incidence of BJL appearance was not significantly different according to the sex, status of H. pylori infection, Vienna classification for phenotype, medications or EGD findings. CONCLUSIONS: BJL appearance on the gastric body and cardia can be a diagnostic clue to CD.  相似文献   
110.
BACKGROUND: This study investigated the utility of the alveolar - arterial oxygen pressure difference (AaDO (2)) in predicting the short-term prognosis of acute pulmonary embolism (PE). METHODS AND RESULTS: This study retrospectively enrolled 114 consecutive patients with acute PE, diagnosed by either spiral computed tomography or high probability ventilation - perfusion lung scans. During the first 24 h of admission, all patients had initial artery blood gas collected under room air. Patient exclusion criteria were chronic lung disease, septic emboli, and moderate and low probability lung scans. Patients were assigned to 2 groups based on either 30-day death or a 30-day composite event. Receiver operating characteristic analyses was used to determine the AaDO(2) cut-off value for predicting primary and composite endpoints. Statistical analysis demonstrated significant differences in AaDO(2) between the 30-day composite endpoint group and the 30-day composite event-free survival group (p=0.012). The AaDO(2) had a strong trend between the 30-day death group and the survival group (p=0.062). The best cut-off value for AaDO(2) was 53 mmHg and using this, the positive predictive value for 30-day death was 25% and the negative predictive value was 92%. For the 30-day composite endpoint, the positive predictive value for AaDO(2) was 35%, and the negative predictive value was 84%. In this study, thrombocytopenia was also an indicator of poor prognosis for patients with acute PE. CONCLUSION: The AaDO(2) measurement is a highly useful and simple measurement for predicting short-term prognosis in patients with acute PE. It has high negative predictive value and moderate positive predictive value for 30-day death and 30-day composite event. Aggressive thrombolytic treatment strategies should be considered for patients with an initial poor prognostic parameter (ie, AaDO(2) >or=53 mmHg).  相似文献   
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