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991.
The Usher syndromes are genetically distinct disorders which share specific phenotypic characteristics. This paper describes a set of clinical criteria recommended for the diagnosis of Usher syndrome type I and Usher syndrome type II. These criteria have been adopted by the Usher Syndrome Consortium and are used in studies reported by members of this Consortium. © 1994 Wiley-Liss, Inc.  相似文献   
992.
The molecular basis underlying the development and progression of gallbladder carcinoma (GBC) remains poorly understood. To evaluate the roles of p21(WAF1/CIP1) and p53 in gallbladder carcinogenesis and to assess their prognostic significance for patients with GBC, we used immunohistochemistry to examine the expression of p21(WAF1/CIP1) and p53 protein in a series of surgically resected specimens, including normal epithelia, precancerous lesions adenoma, and dysplasia, and carcinomas of the gallbladder. Reduced p21(WAF1/CIP1) expression was frequently observed in carcinomas (18 of 37 lesions; 49%), and even in precancerous lesions adenomas (3 of 7; 43%) and dysplasias (5 of 5; 100%). p53 overexpression was detected in 43% of the adenomas, 60% of the dysplasias and 57% of the carcinomas. There was an inverse relationship between p21(WAF1/CIP1) and p53 expression in GBCs (P =.01). Survival analysis indicated that reduced p21(WAF1/CIP1) expression was significantly associated with shortened disease-free and overall survival (P =.04 and.03, respectively) for patients with stages II to IV GBCs. These observations suggest that reduced p21(WAF1/CIP1) expression and p53 overexpression contribute to GBC from an early stage and that determination of p21(WAF1/CIP1) expression in surgically resected specimens would add prognostic information to conventional pathologic examinations for patients with advanced-stage GBC.  相似文献   
993.
994.
Rao ZR  Ge X  Qiou JY  Yang T  Duan L  Ju G 《Neuroscience research》2000,38(2):139-146
Forebrain heat shock protein 70 (HSP70) immunohistochemical reactivity was investigated in rats subjected to gamma knife irradiation focusing on the right caudate putamen nucleus. The forebrain sections of all experimental animals were processed with anti-HSP70 antiserum and then by avidin-biotin peroxidase complex immunohistochemistry after gamma ray irradiation with a dose of 100Gy and they each survived for different times (from 30 min to 30 days). Some neurons, glial cells, and endothelial cells were HSP70-like immunoreactivity (HSP70-LI) positive. HSP70-LI was mainly distributed in the target area of irradiation, as well as in non-target regions, e.g. the cortex, hippocampus, and hypothalamus, etc. The expression and change of HSP70-LI from 3 h to 30 days after irradiation followed the following rules: (1) Within 3 to 24 h, the dilated vessels with HSP70-LI endothelial cells were found at first, and a few lightly stained HSP70-LI neurons and glias were observed in the target and non-target regions; (2) In 3-7 days, darkly stained HSP70-LI neurons and glias were apparently increased and formed an expression peak. From 14 to 30 days, HSP70-LI cells were distinctly decreased and became weakly stained or negative. These results suggested that although the irradiation target of the gamma knife was localized, the response to irradiation occurred extensively.  相似文献   
995.
Wong HT  Cheng SC  Chan EW  Sheng ZT  Yan WY  Zheng ZX  Xie Y 《Virology》2000,278(1):27-35
VP1 is a capsid protein of foot-and-mouth disease virus (FMDV) and contains epitopes of the virus. Plasmids encoding two VP1 epitopes (amino acid residues 141-160 and 200-213) and a host-self immunoglobulin molecule were constructed to produce a new type of FMD DNA vaccine. Two plasmids, namely, pCEIM and pCEIS, containing mouse immunoglobulin (IgG) or swine IgG were subjected to immunogenicity testing in mice and swine, respectively. In mice administrated pCEIM in the abdomen using a genegun, both FMDV-specific T-cell proliferation and neutralizing antibodies were detected. In swine immunized with pCEIS at the back of the ear, immune responses were achieved after the second administration. Swine showed a T-cell proliferative response with a stimulation index (SI) of up to 8.1 and a neutralizing antibody response that was able to protect suckling mice from 10(2) LD(50) (lethal dose 50) FMDV challenge. To compare the immunogenicity of the DNA-based vaccine candidate, versus the protein-based vaccine candidates, a second group of swine was immunized with the protein F1-scIgG, which was encoded by the plasmid pCEIS. Injection with F1-scIgG elicited a T-cell proliferative response of SI < 1.7 and a neutralizing antibody response that protected suckling mice from up to 10(5) LD(50) FMDV challenge. In the challenge test, three of three swine immunized with pCEIS were fully protected from FMDV challenge.  相似文献   
996.
We have produced a murine monoclonal antibody (MAb), ZX10, recognizing the NTPase/helicase domain of the hepatitis C virus (HCV) nonstructural 3 protein (NS3), from which we designed a single-chain variable fragment (ScFv). The ZX10 MAb recognized a discontinuous epitope of the NTPase/helicase domain, of which the linear sequence GEIPFYGKAIPL at residues 1371 to 1382 constitutes one part. cDNAs from variable regions coding for the heavy and light chains were cloned, sequenced, and assembled into the NS3-ScFv, which was inserted into procaryotic and eucaryotic expression vectors. Escherichia coli-expressed NS3-ScFv inhibited the binding of the ZX10 MAb to NS3, confirming a retained specificity. However, the ability to bind the peptide 1371-1382 had been lost. In vitro-translated NS3-ScFv and HCV NS3/NS4A were coprecipitated by antibodies to HCV NS4A, confirming the in vitro activity of the NS3 ScFv. Thus, we have designed a functional NS3 NTPase/helicase domain-specific ScFv which should be evaluated further with respect to disturbing enzymatic functions of the NS3 protein.  相似文献   
997.
BACKGROUND: Glucocorticoid-resistant bronchial asthma is characterized by failure of corticosteroids to suppress key asthma-relevant, cell-mediated inflammatory responses in the airways. OBJECTIVE: The mechanism of this phenomenon is not clear but may involve aberrant expression of the beta-isoform of the glucocorticoid receptor. METHODS: We have measured expression of the alpha- and beta-glucocorticoid receptor isoforms in tuberculin-driven cutaneous cell-mediated inflammatory lesions in people with asthma who are glucocorticoid sensitive and resistant after 9 days of therapy with oral prednisolone (40 mg/day) or matching placebo in a random order, crossover design. RESULTS: After placebo therapy, the mean numbers of cells expressing glucocorticoid receptor alpha immunoreactivity in the lesions evoked in glucocorticoid-sensitive and -resistant patients with asthma were statistically equivalent. The numbers of cells expressing glucocorticoid receptor beta were significantly elevated in the patients who were glucocorticoid resistant, resulting in an 8-fold higher ratio of expression of glucocorticoid receptor alpha/glucocorticoid receptor beta in the patients who were glucocorticoid sensitive. Glucocorticoid receptor alpha/glucocorticoid receptors beta were colocalized to the same cells. Oral prednisolone therapy was associated with a significant decrease in the numbers of cells expressing glucocorticoid receptor alpha but not glucocorticoid receptor beta in the subjects who were glucocorticoid sensitive. No significant change was found in the numbers of cells expressing glucocorticoid receptor alpha and glucocorticoid receptor beta in the patients who were glucocorticoid resistant. Prednisolone therapy reduced the ratio of glucocorticoid receptor alpha/glucocorticoid receptor beta expression for the patients who were glucocorticoid sensitive to a level seen in the patients who were glucocorticoid resistant before therapy. CONCLUSION: Because glucocorticoid receptor beta inhibits alpha-glucocorticoid receptor-mediated transactivation of target genes, the increased expression of glucocorticoid receptor beta in inflammatory cells might be a critical mechanism for conferring glucocorticoid resistance.  相似文献   
998.
A monoclonal antibody enzyme-linked immunosorbent assay (ELISA) was developed to detect Cryptosporidium parvum oocysts in bovine feces. Fecal oocysts were concentrated by centrifugation through Formalin-ethyl acetate solution and captured with monoclonal antibody 18.280.2 reactive with C. parvum oocysts. Captured oocysts were detected with goat anti-oocyst serum, following the addition of a peroxidase conjugate of rabbit anti-goat immunoglobulin and O-phenylenediamine substrate. The assay was specific for Cryptosporidium sp. oocysts and did not detect oocysts of Eimeria auburnensis, Eimeria bovis, Eimeria ellipsoidalis, or Eimeria zuernii. Assay sensitivity allowed detection of 3 x 10(5) oocysts per ml of feces, compared with 1 x 10(6) oocysts per ml detected by examination of acid-fast-stained fecal smears and 1 x 10(3) oocysts per ml detected by indirect immunofluorescence. The capture ELISA was suitable for diagnostic analysis of bovine fecal samples and for assessment of oocyst shedding in experimentally infected calves. This assay may also prove useful for diagnostic assessment of humans in which cryptosporidiosis is suspected.  相似文献   
999.
Nasopharyngeal Streptococcus pneumoniae isolates colonising young children are representative of isolates causing clinical disease. This study determined the frequency of macrolide-non-susceptible pneumococci, as well as their phenotypic and genotypic characteristics, among pneumococci collected during two cross-sectional surveillance studies of the nasopharynx of 2847 children attending day-care centres in the Athens metropolitan area during 2000 and 2003. In total, 227 macrolide-non-susceptible pneumococcal isolates were studied. Increases in macrolide non-susceptibility, from 23% to 30.3% (p <0.05), and in macrolide and penicillin co-resistance, from 3.4% to 48.6% (p <0.001), were identified during the study period. The M resistance phenotype, associated with the presence of the mef(A)/(E) gene, predominated in both surveys, and isolates carrying both mef(A)/(E) and erm(AM) were identified, for the first time in Greece, among the isolates from the 2003 survey. Pulsed-field gel electrophoresis analysis of the isolates from the 2000 survey indicated the spread of a macrolide- and penicillin-resistant clone among day-care centres. The serogroups identified most commonly in the study were 19F, 6A, 6B, 14 and 23F, suggesting that the theoretical protection of the seven-valent conjugate vaccine against macrolide-non-susceptible isolates was c. 85% during both study periods.  相似文献   
1000.
Platelet 5-HT levels and scores on the 17-item Hamilton Rating Scale for Depression (HRS) were studied in patients with unipolar depression before and after antidepressant treatment. Before treatment there were no differences in platelet 5-HT values or in HRS scores between patients who showed a good and a poor therapeutic response. Repeated administration of 5-HT uptake inhibitors (amitriptyline, clovoxamine, fluvoxamine) for 28 days markedly decreased platelet 5-HT levels. Chronic treatment with trazodone or maprotiline (weak inhibitors of platelet 5-HT uptake) produced no changes in platelet 5-HT levels. No significant correlation was observed between platelet 5-HT concentrations and the HRS scores before or during treatment. The findings suggest that the changes in platelet 5-HT levels after antidepressant treatment are mainly due to the effects of antidepressants on the 5-HT uptake system.  相似文献   
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