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41.
Summary In a phase I study of BRL43694A, a 5HT3-receptor antagonist, a single dose of 40 g/kg was given to 24 patients. All patients received cytostatic treatment expected to cause nausea and vomiting. During the first 24 h, 12 patients were completely protected from nausea and vomiting, 4 experienced nausea and 8 had moderate vomiting; mild headache occurred in 10 patients. No cardiovascular (including ECG) changes took place. Apart from headache, no neurological side effects occurred.Supported by a grant from the National Cancer Association of South Africa  相似文献   
42.
Upper gastrointestinal complaints are common in Kenya. Though these have remained unchanged over the last 20 years, the pattern of upper gastrointestinal disease on endoscopic examination seems to be changing. There appears to be progressive increase in oesophagitis and cancer of the stomach. Peptic ulcer disease has remained stable while Cancer of the oesophagus is still common. The paper intends to report on endoscopic findings at the Centre for Clinical Research, Kenya Medical Research Institute (KEMRI) over the period October 1998 and May 2001. The sources of information are records made at the time of endoscopy and histology reports on biopsies taken. Seven hundred and sixty eight patients were endoscoped. The male to female ratio was 1.7:1 with mean age +/-SD of 40.8 +/-20.1 years and age range was 3 to 96 years. Majority of the patients had abnormal findings with gastritis being the most common ( 25.8%). It is concluded that gastritis is an important cause of morbidity in Kenya. Oesophagitis, mainly due to gastroesophageal reflux disease, seems to be on the increase. Gastric cancer is not as rare as previously thought and peptic ulcer disease is still common.  相似文献   
43.
44.
CD1d deficiency exacerbates inflammatory dermatitis in MRL-lpr/lpr mice   总被引:2,自引:0,他引:2  
Mechanisms responsible for the development of autoimmune skin disease in humans and animal models with lupus remain poorly understood. In this study, we have investigated the role of CD1d, an antigen-presenting molecule known to activate natural killer T cells, in the development of inflammatory dermatitis in lupus-susceptible MRL-lpr/lpr mice. In particular, we have established MRL-lpr/lpr mice carrying a germ-line deletion of the CD1d genes. We demonstrate that CD1d-deficient MRL-lpr/lpr mice, as compared with wild-type littermates, have more frequent and more severe skin disease, with increased local infiltration with mast cells, lymphocytes and dendritic cells, including Langerhans cells. CD1d-deficient MRL-lpr/lpr mice had increased prevalence of CD4(+) T cells in the spleen and liver and of TCR alpha beta (+)B220(+) cells in lymph nodes. Furthermore, CD1d deficiency was associated with decreased T cell production of type 2 cytokines and increased or unchanged type 1 cytokines. These findings indicate a regulatory role of CD1d in inflammatory dermatitis. Understanding the mechanisms by which CD1d deficiency results in splenic T cell expansion and cytokine alterations, with increased dermal infiltration of dendritic cells and lymphocytes in MRL-lpr/lpr mice, will have implications for the pathogenesis of inflammatory skin diseases.  相似文献   
45.
采用套式聚合酶链反应结合变性聚丙烯酰胺凝胶电泳和银染技术,并构建载脂蛋白CII(ApoCII)基因二核苷酸串联重复序列(TG)n(AG)m及(AG)m序列等位基因梯阶标准;检测正常汉族人群基因型和等位基因频率分布,检出36种(TG)n(AG)m序列基因型、12种等位基因。等位基因为17、18、26-35,其频率分别为0.061、0.011、0.002、0.002、0.054、0.255、0.372、0.084、0.026、0.039、0.052、0.041。检出7种(AG)m序列基因型、4种等位基因。等位基因为6、7、8、9,其频率分别为0.002、0.152、0.812、0.034。与欧洲白种人比较,ApoCII基因二核苷酸串联重复序列(TG)n(AG)m及(AG)m序列等位基因频率分布均具有明显的种族差异性(P<0.01,P<0.01)。  相似文献   
46.
A functional polymorphism in the regulatory region of the serotonin transporter gene (5-HTTLPR) is considered to be a plausible candidate gene for anxiety-related personality traits and for alcoholism. Empirical support for the association between 5-HTTLPR and psychological traits has been somewhat inconsistent; however, observations of the functional dominance of the low-activity s-allele over the l-allele have been more consistent. When studying the influence of particular genes on psychological traits, it seems useful also to assess more biological intermediate traits that may mediate the effects of those genes on the traits of interest. The present study examined relationships between 5-HTTLPR genotype, whole blood serotonin (5-HT) level, and platelet 5-HT binding in 150 Caucasian subjects from 50 biological families. Individuals with the s-allele had lower average platelet 5-HT binding availability than those with the l/l genotype (P<0.025). Whole blood 5-HT level was not associated with 5-HTTLPR genotype. In adult men, those with the s-allele had higher mean scores on the NEO-FFI personality trait of openness than did those with the l/l genotype (P=0.002). The effect was not statistically significant in women (P=0.42), although it was in the same direction. Our findings do not support an association of 5-HTTLPR genotype with alcoholism diagnosis, alcoholism subtype, or the personality trait of neuroticism. The results of this pilot study suggest that further work should examine the mediation of the genetic effects on personality traits by biochemical measures and their moderation by gender.  相似文献   
47.
The relationship between odor identification and cognition has not been previously well characterized. The neuroanatomy of the olfactory system and the frequent finding of olfactory dysfunction in neurodegenerative diseases suggest a likely relationship between odor identification and memory, language, and executive functioning, though previous studies have often failed to demonstrate the expected relationship. The current study examined this relationship in across a continuum of ability levels (N=100). Strongest correlations were found between odor identification and language, most aspects of memory, and a measure of general cognitive functioning. Significant but more modest correlations were seen between odor identification and attention, motor, visuospatial, and executive functions. A regression analysis revealed language as the only significant predictor of olfactory performance. These findings suggest that odor identification is most closely associated with other measures of temporo-limbic functioning. The implications of these findings, particularly in consideration of the assessment of older adults, are discussed.  相似文献   
48.
Cassell GD  Weitzman MD 《Virology》2004,327(2):206-214
Adeno-associated virus (AAV) replicates in the nucleus of infected cells, and therefore multiple nuclear import events are required for productive infection. We analyzed nuclear import of the viral Rep proteins and characterized a nuclear localization signal (NLS) in the C-terminus. We demonstrate that basic residues in this region constitute an NLS that is transferable and mediates interaction with the nuclear import receptor importin alpha in vitro. Mutant Rep proteins are predominantly cytoplasmic and are severely compromised for interactions with importin alpha, but retain their enzymatic functions in vitro. Interestingly, mutations of the NLS had significantly less effect on importin alpha interaction and replication in the context of Rep78 than when incorporated into the Rep68 protein. Together, our results demonstrate that a bipartite NLS exists in the shared part of Rep68 and Rep78, and suggest that an alternate entry mechanism may also contribute to nuclear localization of the Rep78 protein.  相似文献   
49.
Although it is known that systemic diseases such as diabetes result in impaired wound healing, the mechanism for this impairment is not understood. Because fibroblasts are essential for wound repair, we compared the in vitro behavior of fibroblasts cultured from diabetic, leptin receptor-deficient (db/db) mice with wild-type fibroblasts from mice of the same genetic background in processes important during tissue repair. Adult diabetic mouse fibroblast migration exhibited a 75% reduction in migration compared to normal fibroblasts (P < 0.001) and was not significantly stimulated by hypoxia (1% O(2)), whereas wild-type fibroblast migration was up-regulated nearly twofold in hypoxic conditions (P < 0.05). Diabetic fibroblasts produced twice the amount of pro-matrix metalloproteinase-9 as normal fibroblasts, as measured by both gelatin zymography and enzyme-linked immunosorbent assay (P < 0.05). Adult diabetic fibroblasts exhibited a sevenfold impairment in vascular endothelial growth factor (VEGF) production (4.5 +/- 1.3 pg/ml versus 34.8 +/- 3.3 pg/ml, P < 0.001) compared to wild-type fibroblasts. Moreover, wild-type fibroblast production of VEGF increased threefold in response to hypoxia, whereas diabetic fibroblast production of VEGF was not up-regulated in hypoxic conditions (P < 0.001). To address the question whether these differences resulted from chronic hyperglycemia or absence of the leptin receptor, fibroblasts were harvested from newborn db/db mice before the onset of diabetes (4 to 5 weeks old). These fibroblasts showed no impairments in VEGF production under basal or hypoxic conditions, confirming that the results from db/db fibroblasts in mature mice resulted from the diabetic state and were not because of alterations in the leptin-leptin receptor axis. Markers of cellular viability including proliferation and senescence were not significantly different between diabetic and wild-type fibroblasts. We conclude that, in vitro, diabetic fibroblasts show selective impairments in discrete cellular processes critical for tissue repair including cellular migration, VEGF production, and the response to hypoxia. The VEGF abnormalities developed concurrently with the onset of hyperglycemia and were not seen in normoglycemic, leptin receptor-deficient db/db mice. These observations support a role for fibroblast dysfunction in the impaired wound healing observed in human diabetics, and also suggest a mechanism for the poor clinical outcomes that occur after ischemic injury in diabetic patients.  相似文献   
50.
The cloning, expression and characterization of a murine-human chimeric antibody with specificity for the pre-S2 surface antigen (Ag) of hepatitis B virus (HBV) is described. The heavy and light chain variable region (VH and VL) genes encoding the murine monoclonal antibody (mAb) were isolated and combined with human γ 1 and κ constant region genes, respectively. The expression vectors containing the chimeric heavy and light chain genes were sequentially electroporated into murine Sp2/0 hybridoma cells and transfectomas secreting chimeric antibody were isolated. The chimeric antibody was purified and characterized by ELISA, Western analysis and competition immunoassay, demonstrating that the transfectoma functionally express and secrete murine-human chimeric antibody which retained the specificity and affinity of the parental murine mAb.  相似文献   
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