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排序方式: 共有872条查询结果,搜索用时 15 毫秒
91.
KH Yeh MT Lin DT Lin JL Tang LT Lui JF Lin YS Chang AL Cheng SC Yu KJ Chang YC Chen 《Canadian Metallurgical Quarterly》1998,49(3):237-244
BACKGROUND: Epidemiologic studies are necessary to determine the prevalence of allergic diseases. This varies widely depending on allergen preparations and patients studied. OBJECTIVE: To investigate the prevalence of atopic disease, skin test reactivity, total and specific IgE to common allergens, and other variables in a sample of students from Málaga, southern Spain. METHODS: Three hundred sixty-five students (age 17.9 +/- 1.18) were interviewed by an allergist. Skin prick tests were performed with Dermatophagoides pteronyssinus, Artemisia vulgaris, Plantago lanceolata, Chenopodium album, Olea europaea, Phleum pratense, Parietaria judaica, Cynodon dactylon, Alternaria tenuis, and cat dander. Total and specific IgE to D. pteronyssinus, Olea, and Parietaria were determined. RESULTS: Of all subjects studied, 19.9% suffered from rhinoconjunctivitis, 4.1% rhinoconjunctivitis plus asthma, 3.1% asthma alone, and 0.8% atopic dermatitis; 46.4% had a positive skin test to at least one allergen (28.2% to D. pteronyssinus, 20.4% to Olea, 13.8% to Phleum); and 43% had total IgE > 100 kU/L and 44.7% a family history of atopy. Allergic symptoms were strongly associated with skin test positivities and family allergic history. Patients with asthma or skin prick test positive had higher total IgE values than others (P < .01). There was a significant correlation between specific IgE values and wheal size in skin test. CONCLUSIONS: Our findings confirm the high prevalence of atopic diseases, and the close relationship of skin tests reactivity (or presence of specific IgE) to allergens with symptoms of asthma and rhinitis. The presence of a family history of allergic diseases influences the development of positive skin tests and atopic illness. Dermatophagoides pteronyssinus and pollen of Olea europaea were found to be the most common allergens. 相似文献
92.
OBJECTIVE: To compare the expression of gelatinases in the corneal epithelium and stroma after laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK). METHODS: Rabbit eyes were treated with LASIK (n=11), PRK (n=12), or corneal flap construction (n=12); 4 eyes served as unwounded controls. Zymography was performed on the central epithelium and the stroma 1, 3, and 7 days after surgery to determine the expression of gelatinases. RESULTS: Epithelial expression of gelatinase B in the LASIK group (0%-25%) was lower than that in the PRK group at all time points (50%-100%) and was identical to the corneal flap group. Stromal expression of gelatinases A and B was similar after LASIK and PRK, but was minimal after corneal flap construction at all time points. Epithelial expression of gelatinase A was similar for the first 3 days after LASIK and PRK but not thereafter. CONCLUSIONS: Gelatinase B epithelial expression was up-regulated after PRK but not after LASIK. Gelatinase B stromal expression was up-regulated after both procedures. CLINICAL RELEVANCE: Differences in wound healing and subepithelial scarring after these 2 procedures may be related to gelatinase B. 相似文献
93.
94.
DJ Sonneveld DT Sleijfer HS Koops ME Keemers-Gels WM Molenaar HJ Hoekstra 《Canadian Metallurgical Quarterly》1998,82(7):1343-1351
BACKGROUND: Mature teratoma is often found in resected retroperitoneal residual tumor masses (RRTM) after chemotherapy for disseminated nonseminomatous testicular germ cell tumors (NSTGCT). The aim of this report is to describe the clinical course of patients after resection of residual teratoma, with particular emphasis on relapse with either growing mature teratoma or secondary non-germ cell malignancy. METHODS: During the period 1979-1995, 113 patients underwent a laparotomy for resection of RRTM after chemotherapy for NSTGCT. Only patients with mature teratoma in the RRTM were included in the current study, and data on the patients who experienced relapse were studied in detail. RESULTS: Mature teratoma was found in 51 patients (45.1%) with RRTM resected after chemotherapy. Nine of these 51 patients (17.6%) relapsed; the relapses resulted from growing mature teratoma in 5 patients (9.8%), secondary non-germ cell malignancy in 3 patients (5.9%), and recurrent germ cell malignancy in 1 patient (2.0%). The primary treatment for all relapsing patients was surgical excision. All five patients with growing mature teratoma are alive without evidence of disease, as is the patient with recurrent germ cell malignancy. One of the three patients with non-germ cell malignancy died of disease, and the remaining two are alive with disease. CONCLUSIONS: Long term follow-up after resection of postchemotherapy residual teratoma is indicated because a proportion of patients develop growing mature teratoma or a secondary non-germ cell malignancy. The treatment for these recurrences should be complete surgical excision. 相似文献
95.
PURPOSE: We evaluated the feasibility of 18 Fluoride Positron Emission Tomography (18F-PET), investigated the characteristics appearance of bony structures, and compared the quality of 18F-PET images with conventional bone scans (BS). METHOD: 18F-PET scans were performed in 59 patients additional to conventional bone scintigraphy. RESULTS: Even very small details in the spine like the spinous and transverse processes were clearly visible with 18F-PET. Only half of these structures were visualised with BS. When visualising the vertebral bodies of the first rib from the clavicles and the twelfth rib from the kidneys, we arrived at similar results. Hot spots in the skull or at the manubriosternal joint were observed in 29% of the patients without any evidence of trauma, degeneration or metastasis. CONCLUSION: 18F-PET shows more details of the skeleton compared to BS. Some hot spots not occurring with BS must be regarded as physiological. 相似文献
96.
D Ford DF Easton M Stratton S Narod D Goldgar P Devilee DT Bishop B Weber G Lenoir J Chang-Claude H Sobol MD Teare J Struewing A Arason S Scherneck J Peto TR Rebbeck P Tonin S Neuhausen R Barkardottir J Eyfjord H Lynch BA Ponder SA Gayther M Zelada-Hedman 《Canadian Metallurgical Quarterly》1998,62(3):676-689
The contribution of BRCA1 and BRCA2 to inherited breast cancer was assessed by linkage and mutation analysis in 237 families, each with at least four cases of breast cancer, collected by the Breast Cancer Linkage Consortium. Families were included without regard to the occurrence of ovarian or other cancers. Overall, disease was linked to BRCA1 in an estimated 52% of families, to BRCA2 in 32% of families, and to neither gene in 16% (95% confidence interval [CI] 6%-28%), suggesting other predisposition genes. The majority (81%) of the breast-ovarian cancer families were due to BRCA1, with most others (14%) due to BRCA2. Conversely, the majority of families with male and female breast cancer were due to BRCA2 (76%). The largest proportion (67%) of families due to other genes was found in families with four or five cases of female breast cancer only. These estimates were not substantially affected either by changing the assumed penetrance model for BRCA1 or by including or excluding BRCA1 mutation data. Among those families with disease due to BRCA1 that were tested by one of the standard screening methods, mutations were detected in the coding sequence or splice sites in an estimated 63% (95% CI 51%-77%). The estimated sensitivity was identical for direct sequencing and other techniques. The penetrance of BRCA2 was estimated by maximizing the LOD score in BRCA2-mutation families, over all possible penetrance functions. The estimated cumulative risk of breast cancer reached 28% (95% CI 9%-44%) by age 50 years and 84% (95% CI 43%-95%) by age 70 years. The corresponding ovarian cancer risks were 0.4% (95% CI 0%-1%) by age 50 years and 27% (95% CI 0%-47%) by age 70 years. The lifetime risk of breast cancer appears similar to the risk in BRCA1 carriers, but there was some suggestion of a lower risk in BRCA2 carriers <50 years of age. 相似文献
97.
98.
DT Uehling WJ Hopkins E Balish Y Xing DM Heisey 《Canadian Metallurgical Quarterly》1997,157(6):2049-2052
PURPOSE: Decreased local immunity to uropathogenic bacteria may be a factor predisposing women to recurrent urinary tract infections. Our phase I study demonstrated the safety of a multi-strain vaccine administered as a vaginal suppository. A phase II study was conducted to determine vaccine efficacy. MATERIALS AND METHODS: A total of 91 women susceptible to recurrent urinary tract infections was entered into the study and the courses were analyzed in a randomized, double-blind, placebo controlled trial of vaginal mucosal immunization. Subjects received 3 vaginal suppositories at weekly intervals. Depending on the treatment group each suppository contained 1 of 2 vaccine doses or suppository material only. Each patient was followed for 5 months to record infection episodes, and obtain urine, vaginal irrigates and serum to measure immunological responses. RESULTS: Immunogen treated women who were off antibiotic prophylaxis throughout the study had a significant delay in interval to reinfection during the first 8 weeks compared to women receiving placebo. Mean interval until reinfection was delayed from 8.7 weeks for placebo treated to 13 weeks for vaccine treated women. Immunological responses in serum, urine and vaginal fluid were variable. No serious adverse effects were observed. CONCLUSIONS: These data demonstrate that vaginal mucosal immunization can enhance resistance to urinary tract infections in susceptible patients. 相似文献
99.
100.
Extracellular calcium/polyvalent cation-sensing receptors (CaR) couple to G proteins and contain highly conserved extracellular cysteine residues. Immunoblotting of proteins from rat kidney inner medullary collecting duct endosomes with CaR-specific antibodies reveals alterations in the apparent molecular mass of CaR depending on protein denaturation conditions. When denatured by SDS under nonreducing conditions, CaR migrates as a putative dimeric species of 240-310 kDa. This is twice the predicted molecular mass of the CaR monomer observed after SDS denaturation in the presence of sulfhydryl-reducing agents. In sucrose density gradients, Triton X-100-solubilized CaR sediments as a 220-kDa complex, not explainable by binding of G proteins to CaR monomers. Treatment of Triton-soluble CaR with divalent (Ca2+, Mg2+) and trivalent (Gd3+) metal ion CaR agonists, but not monovalent ions (Na+), partially shifts the electrophoretic mobility of CaR under reducing conditions from a predominantly monomeric to this putative dimeric species on immunoblots in a manner similar to their rank order of functional potency for CaR activation (Gd3+ > Ca2+ > Mg2+). This Ca2+ effect is blocked by pretreatment with N-ethylmaleimide. We conclude that disulfide bonds present in CaRs mediate formation of dimers that are preserved in Triton X-100 solution. In addition, CaR exposure to Ca2+ induces formation of additional disulfide bonds within the Triton-soluble CaR complex. 相似文献