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21.
Clostridium botulinum type B was detected by multiplex PCR in the intestinal contents of a suddenly deceased 11-week-old infant and in vacuum cleaner dust from the patient's household. C. botulinum was also isolated from the deceased infant's intestinal contents and from the household dust. The genetic similarity of the two isolates was demonstrated by pulsed-field gel electrophoresis and randomly amplified polymorphic DNA analysis, thereby confirming that dust may act as a vehicle for infant botulism that results in sudden death.  相似文献   
22.
Some skin and soft tumors, which generally are assumed to be derived from endothelial cells or blood vessels, were characterized with fluorochrome-labeled Ulex europaeus I agglutinin (UEA I), recently shown to bind specifically to endothelial cells in various normal human tissues. The staining pattern was compared with that obtained with immunostaining using antibodies against factor-VIII-related antigen (FVIII-RAG), a known marker for endothelial cells. The results showed that UEA-I is a specific and a more sensitive marker for the endothelial cells in benign vascular lesions as compared with anti-FVIII-RAG. UEA-I also stained many neoplastic cells of endothelial sarcomas, which generally were negative for FVIII-RAG. Melanomas, anaplastic carcinomas, and other types of sarcomas were negative for both UEA-I and FVIII-RAG. The results suggest that UEA-I lectin is a specific and sensitive adjunct tool in demonstrating endothelial cells and endothelial derivation of human tumors.  相似文献   
23.
A cytomegalovirus (CMV)-specific sandwich hybridization test was constructed by using two adjacent BamHI DNA fragments of CMV DNA as reagents. The fragments were cloned into two different vectors. One of the recombinants was attached to the filter, and the other was the labeled probe. When present in the sample, CMV DNA mediated labeling of the filter by hybridizing to both the filter-bound DNA and the probe. The sandwich hybridization test was applied for the detection of CMV DNA from urine. DNA was released from virus by 2% Sarkosyl, concentrated by 2-butanol extraction and isopropanol precipitation, denatured, and finally subjected to the sandwich hybridization test. As a result, 70 to 90% of the original viral DNA could be recovered and demonstrated by the quantitative hybridization reaction. Urine could be stored at room temperature in Sarkosyl for at least 2 days without affecting the detectability of CMV. The clinical applicability of the test was evaluated by studying urine samples from four infants excreting CMV. Sandwich hybridization demonstrated the presence of CMV DNA in all of the specimens. These contained originally 10(5) to 10(8) CMV DNA molecules per ml.  相似文献   
24.
The aim of this study was to examine the distribution of 1 and v integrins (Ints) and some of their ligands in the kidneys of patients with congenital nephrotic syndrome of the Finnish type (CNF) and in controls using indirect immunofluorescence with monoclonal antibodies. The mesangial reactivity of Int 1 and Int 1 subunits was more variable and an increased glomerular reactivity with Int 3 and Int-6 antibodies was found in CNF kidneys than in controls. Int 2 subunit was either completely missing from or found in significantly lesser amounts in CNF kidney glomeruli. The immunoreactivity for Int v was more variable, fainter and also more granular in CNF samples than in control kidneys. The glomerular reactivity for Int 5 was more diffuse and weaker, and in sclerotic Bowman's capsules more intense in CNF kidneys than in controls. Immunoreactivity for Int 6 was restricted and was comparable in extent in CNF and control kidneys. Of the extracellular matrix components studied, the expression of EDAFn, EDBFn, OncFn, Ln 2 chain, Ln 1 chain and tenascin was increased. This is also seen in several glomerular diseases with inflammation and sclerosis. Immunoreactivity for vitronectin was decreased. Several differences were found in the intensity or location of the immunostaining for the 1 and v Ints and their ligands in CNF kidneys compared with controls, which have not been found in any other proteinuric disease. Disturbed Int expression pattern in CNF may specifically reflect the disturbance of glomerular function caused by the primary defect in this disease.  相似文献   
25.
Our aim was to study the associations between maternal vitamin C and iron intake during pregnancy and the offspring’s risk of developing islet autoimmunity and type 1 diabetes. The study was a part of the Finnish Type 1 Diabetes Prediction and Prevention (DIPP) prospective birth cohort including children genetically at risk of type 1 diabetes born between 1997–2004. The diets of 4879 mothers in late pregnancy were assessed with a validated food frequency questionnaire. The outcomes were islet autoimmunity and type 1 diabetes. Cox proportional hazards regression analysis adjusted for energy, family history of diabetes, human leukocyte antigen (HLA) genotype and sex was used for statistical analyses. Total intake of vitamin C or iron from food and supplements was not associated with the risk of islet autoimmunity (vitamin C: HR 0.91: 95% CI (0.80, 1.03), iron: 0.98 (0.87, 1.10)) or type 1 diabetes (vitamin C: 1.01 (0.87, 1.17), iron: 0.92 (0.78, 1.08)), neither was the use of vitamin C or iron supplements associated with the outcomes. In conclusion, no association was found between maternal vitamin C or iron intake during pregnancy and the risk of islet autoimmunity or type 1 diabetes in the offspring.  相似文献   
26.
Respond on comments on Lieberman's article: Cyclosiloxanes Produce Fatal Liver and Lung Damage in Mice. Environ Health Perspect 107:161-165  相似文献   
27.
Context  Many recent cross-sectional studies have suggested that lack of early exposure to communicable diseases, including measles, in affluent countries may have increased rates of atopic disease. Objective  To study the association between natural measles infection and atopy. Design and Setting  Cross-sectional nationwide study in Finland using data gathered between November 1, 1982, and June 30, 1986. Subjects  A total of 547,910 individuals aged 14 months to 19 years who at the time of measles-mumps-rubella (MMR) vaccination had relevant information collected on the occurrence of measles and allergic rhinitis, eczema, and asthma. Main Outcome Measures  Lifetime occurrence of atopic manifestations in subjects who had had measles compared with those who had not, expressed as age-specific and age-adjusted prevalence ratios. Results  The age-adjusted prevalence ratio of atopic manifestations among those who had had measles (n = 20,690) compared with those who had not (n = 527,220) was 1.32 (95% confidence interval [CI], 1.27-1.36) for eczema, 1.41 (95% CI, 1.33-1.49) for rhinitis, and 1.67 (95% CI, 1.54-1.79) for asthma. The positive association between measles and atopy was evident at all ages, in both urban and rural dwellers, and among subjects with many or few contacts at home or in day care. Conclusions  Based on our data, measles and atopy occur more frequently together than expected, which does not support the hypothesis that experiencing natural measles infection offers protection against atopic disease.   相似文献   
28.
睾丸下降不完全是常见的先天性泌尿生殖系统畸形,在新生男婴中的发病率为2%~9%。隐睾症的病因可能是多因素的,而雄激素效应不足被认为是其病因之一。在外观健康的个体中有一种普遍的基因变异性黄体生成素(V-LH)。与自然型的黄体生成素(W T-LH)相比,V-LH在体外的生物活性较高而  相似文献   
29.
30.
This study evaluates the suitability of Xpert HPV (Cepheid, Sunnyvale, CA, USA) test for cervical and tonsillar formalin‐fixed paraffin‐embedded (FFPE) tissue samples as compared to the tests currently used in diagnostics. Cervical biopsies and liquid cytology (LC) samples were collected from 48 women attending colposcopy. Biopsies were processed for histology and tested for hrHPV using Xpert HPV. LC samples were tested using Xpert and Hybrid Capture 2 (HC2; Qiagen, Hilden, Germany) tests. Also 29 archived tonsillar carcinoma samples were tested using Xpert, and the results were compared with histology and immunohistochemical p16INK4a (p16) staining. Among valid cervical LC samples 46.8% were hrHPV positive using Xpert test and 55.3% with HC2. The sensitivity of Xpert was 84.6% as compared to HC2, and overall test concordance was 91.5%. Test concordance between valid Xpert results from biopsies and LC samples was 84.6%. Among valid tonsillar samples 70.4% were hrHPV positive, and concordance of 96.3% was found between Xpert and p16 staining. To conclude, Xpert HPV test cartridge provides a convenient platform to test individual samples, including FFPE samples. Further studies are needed to establish whether test sensitivity is sufficient to reliably differentiate between hrHPV positive and hrHPV negative head and neck carcinomas.  相似文献   
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