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981.
Cystic fibrosis (CF) is the most common fatal autosomal recessive multisystem disorder, which occurs mainly in European-derived populations. The incidence of CF varies between 1 in 2000 to 3000 live-births in various ethnic groups. The disease is rare in East Asians. Here we report a 9 year old Thai male patient, who was diagnosed to have CF based on recurrent pneumonia, a slow weight gain, pancreatic insufficiency and repeatedly elevated sweat chloride levels by two different methods. A comprehensive genetic analysis showed the splicing mutation, 1898+ 1G-->T, which was apparently of maternal origin. Literature search found 39 documented cases of CF patients in East Asians. CFTR (MIM# 602421) genotyping was performed in 14 patients including our patient and in 9 of them a CF allele was identified. The findings seem to indicate that the splicing mutations, 1898+ 1G-->T and 1898+ 5G-->T are more common in East Asian CF patients.  相似文献   
982.
Dopamine plays important roles in the regulation of central nervous system (CNS) development and functions. In vertebrates, two families of dopamine receptors, collectively known as dopamine D1 and D2 receptors, have been identified. Recently, dopamine receptors have been targeted by pharmacological and therapeutic studies of neurological disorders, such as Parkinson's disease. Here, we report a study on the molecular characterization of dopamine D1 receptor in zebrafish (Danio rerio). We cloned the full-length cDNA of a zebrafish dopamine D1 receptor, designated as drd1. The sequence of drd1 shares high homology to the sequences of dopamine D1 receptors in mammalian, amphibian, and other fish species. drd1 is expressed in the CNS. The first drd1 expression was observed at approximately 30 hours postfertilization, at which time the expression was seen in the developing diencephalon and hindbrain. In developing retinas, the expression of drd1 was detected in the inner nuclear layer with the exception of the marginal zones. In adult retinas, drd1 expression was detected in most cell types in the inner and outer nuclear layers as well as ganglion cell layer. Differential expression of drd1 in developing and adult retinas may play various roles in regulating visual system functions.  相似文献   
983.
Vesicular stomatitis virus (VSV), when reproduced in human tumor cell lines, assembled a specific subset of cell-derived proteins. These were detected by [35S]methionine labeling of cells prior to infection and subsequent immunoprecipitation of VSV grown in these cells, as well as by direct immunoprecipitation of labeled cell extracts with antiserum directed against the VSV-assembled proteins. Their molecular weight (Mr) ranged between 15K and 180K; the larger proteins were glycosylated. Two of the major protein species (gp88 and gp130) were common to all four cell lines used (HeLa—cervical carcinoma, T47D—breast carcinoma, and HMB2 and SK1477—two melanoma cell lines). Proteins of other molecular weights were detected only in one or two of the cell lines. The melanoma cell lines (even in the absence of VSV) shed large particulate material which had contained the same spectrum of proteins that were assembled by VSV. The major protein component had an Mr of 30K. Some of the VSV-assembled proteins might possibly serve as specific tumor markers. It is also conceivable that the proteins assembled by VSV as well as the large particulate material might be products of defective endogenous human retroviruses.  相似文献   
984.
米非司酮对体外培养人子宫内膜的损伤作用   总被引:7,自引:0,他引:7  
目的 探讨米非司酮对体外培养人子宫内膜的损伤作用。方法 取 5位育龄妇女增殖期的子宫内膜组织并分成两份。一部分用含 15 %胎牛血清及 1%青霉素和链霉素的DMEM培养液培养 (对照组 ) ,另一部分在另加 2 5 μg/ml米非司酮的培养液培养 (米非司酮组 )。 10 0h后取出组织制备电镜样品并观察。结果 对照组的子宫内膜腺上皮出现核仁管道系统(NCS)、巨大线粒体及糖原沉积等分泌期的 3大形态特征。米非司酮组则不仅未见上述特征 ,还出现了线粒体空泡化、腺细胞成片坏死及间质水肿的现象。结论  (1)NCS在人子宫内膜的形成与孕激素无直接关系 ;(2 )在缺乏孕激素的作用下 ,增殖期的子宫内膜仍然可转化为分泌期的形态 ;(3)米非司酮可直接造成人子宫内膜的损伤。  相似文献   
985.
A key advantage in the conversion from film-based to digital radiology is the possibility of a long-term on line electronic archival of patient studies. The popular approach based on optical disk jukeboxes for the long-term archive and magnetic disk storage for data caching is not economically attractive because of the cost of both the jukebox and the medium. Strategies for extending the archival system design with a tape jukebox have been studied. The proposed strategy calls for the use of high-ratio lossy compression together with low-cost tape storage to make long-term on line archiving more affordable. An intelligent prefetching algorithm based on hospital information system and radiologic information system triggers, which in turn are augmented by manual case preparation, can effectively overcome the longer latency of ad hoc retrievals. This longer latency is caused by both system-level bottlenecks and the sequential access constraint of the tape drive. Strategies for image clustering and tape allocation by patient classification also enhance retrieval efficiency. This archival design using image compression, prefetching, and clustering could be implemented in many of the existing teleradiology and picture archiving and communication systems.  相似文献   
986.
高压氧促进成年大鼠神经干细胞的增殖   总被引:5,自引:0,他引:5  
目的:研究高压氧对成年大鼠神经干细胞增殖的影响。方法:采用BrdU免疫组化方法,观察高压氧对成年大鼠神经干细胞增殖的影响,同时通过脑内注射内皮素制备大脑中动脉闭塞(MCAO)模型,对这两种诱导神经干细胞增殖的处理加以比较。结果:高压氧暴露10d,侧脑室前角和外侧壁的BrdU~ 细胞数量显著增加,BrdU~ 细胞核计数显著多于正常组,阳性细胞核反应性也显著增强,多为深染的棕黑色细胞核,其效应与MCAO第8天对BrdU~ 细胞的效应类似;高压氧暴露10d也引起了海马齿状回颗粒细胞层BrdU~ 细胞数量显著增加。结论:反复高压氧暴露可能具有调节脑内神经干细胞增殖与分化的作用。  相似文献   
987.
p53基因是各种人类肿瘤包括食管癌中最常见有突变的基因之一。我们应用激光显微切割,聚合酶链反应(PCR)-杂合性缺失(LOH),PCR-单链构象多态性分析(SSCP),p53测序及免疫组织化学方法,检测了食管癌高发区中国山西省的56例患者食管鳞状细胞癌(ESCC)中p53基因缺失、突变及p53蛋白表达情况,旨在更好理解p53基因突变等变化在食管癌发生发展过程中的作用。  相似文献   
988.
Wai Mun Huang 《Virology》1975,66(2):508-521
During the prereplicative period after the infection of Escherichia coli by phage T4, more than 50 proteins are synthesized. Many of them have been identified with their corresponding genes. Among them, at least 13 are selectively enriched in the membrane preparation. They include the products of the two rII genes, genes 39, 52 (DNA-delay), and others not yet identified. The majority of these proteins (90%) are extractable by the detergent, sarkosyl, and are possibly associated with the inner or cytoplasmic membrane. Based on their electrophoretic migration in SDS-polyacrylamide gels and on their tryptic fingerprints, these proteins are found to be phage induced. Two of the newly synthesized proteins that are selectively enriched in the cell wall or outer envelope fraction are found to be identical with two envelope proteins of the host cell. They are continually synthesized after phage infection although general host protein synthesis is shut off.  相似文献   
989.
The purpose of the present study was to evaluate the effectiveness of an attenuated Salmonella enterica serovar Typhimurium vaccine strain expressing the saliva-binding region (SBR) of the Streptococcus mutans antigen I/II adhesin, either alone or linked with the mucosal adjuvant cholera toxin A2 and B subunits (CTA2/B) and under the control of the anaerobically inducible nirB promoter, in inducing a protective immune response against S. mutans infection. BALB/c mice were immunized by either the intranasal or the intragastric route with a single dose of 10(9) or 10(10) Salmonella CFU, respectively. The Salmonella vaccine strain expressing an unrelated antigen (fragment C of tetanus toxin [TetC]) was also used for immunization as a control. Samples of serum and secretion (saliva and vaginal washes) were collected prior to and following immunization and assessed for antibody activity by enzyme-linked immunosorbent assay. Anti-SBR antibodies were detected in the serum and saliva of experimental animals by week 3 after immunization. A booster immunization at week 17 after the initial immunization resulted in enhanced immune responses to the SBR. The serum immunoglobulin G subclass profiles were indicative of T helper type 1 responses against both the vector and the SBR antigen. To determine the effectiveness of these responses on the protection against S. mutans infection, mice were challenged after the second immunization with a virulent strain of S. mutans which was resistant to tetracycline and erythromycin. Prior to the challenge, mice were treated for 5 days with tetracycline, erythromycin, and penicillin. S. mutans was initially recovered from all of the challenged mice. This bacterium persisted at high levels for at least 5 weeks in control TetC-immunized or nonimmunized mice despite the reappearance of indigenous oral organisms. However, mice immunized with Salmonella clones expressing SBR or SBR-CTA2/B demonstrated a significant reduction in the number of S. mutans present in plaque compared to the control groups. These results provide evidence for the effectiveness of the Salmonella vector in delivering the SBR antigen for the induction of mucosal and systemic immune responses to SBR. Furthermore, the induction of a salivary anti-SBR response corresponded with protection against S. mutans colonization of tooth surfaces.  相似文献   
990.
BACKGROUND: Peanut allergy is a major cause of fatal and near-fatal anaphylactic reactions to foods. There is no curative therapy for this condition. Traditional Chinese medicines have been reported to have antiallergic properties, which might be useful for treating peanut allergy. OBJECTIVE: The purpose of this study was to investigate the effects of a Chinese herbal formula, FAHF-1, on peanut anaphylactic reactions in a mouse model of peanut allergy. METHODS: Mice were sensitized with freshly ground whole peanut in the presence of cholera toxin and boosted 1 and 3 weeks later. FAHF-1 treatment was initiated 1 week later and continued for 7 weeks. After treatment, mice were challenged with peanut, and anaphylactic symptoms, body temperatures, and plasma histamine and IgE levels were measured. T-cell proliferative responses and cytokine production were also determined. RESULTS: FAHF-1 completely blocked peanut-induced anaphylactic symptoms and markedly reduced mast cell degranulation and histamine release. Peanut-specific serum IgE levels were significantly reduced by 2 weeks of treatment at the time of challenge, and they remained lower 4 weeks after discontinuation of treatment. FAHF-1 significantly reduced peanut-induced lymphocyte proliferation as well as IL-4, IL-5, and IL-13 synthesis but not IFN-gamma synthesis. No toxic effects on liver or kidney functions were observed, nor was there any overall immune suppression. CONCLUSION: FAHF-1 protected peanut-sensitized mice from anaphylactic reactions and significantly reversed established IgE-mediated peanut allergy. This suggests that FAHF-1 might prove valuable for the treatment of peanut allergy.  相似文献   
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