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排序方式: 共有336条查询结果,搜索用时 15 毫秒
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S Lopaciuk A J Meissner S Filipecki K Zawilska J Sowier L Ciesielski M Bielawiec S Glowinski E Czestochowska 《Thrombosis and haemostasis》1992,68(1):14-18
In a prospective multicenter trial, 149 consecutive patients with phlebographically proven proximal and/or distal deep vein thrombosis of the leg were randomly allocated to receive subcutaneously for 10 days either low molecular weight heparin CY 216 (Fraxiparine) in a fixed dose or unfractionated heparin (UFH) in doses adjusted according to the activated partial thromboplastin time. Pre- and post-treatment phlebograms were assessed blindly using the Arnesen's score system in 134 patients available for analysis of the treatment efficacy. The mean phlebographic score after 10 days of treatment was significantly decreased in both groups (p less than 0.001) in comparison with the baseline score but the difference in score changes between the two groups was not statistically significant. There was an improvement in 45/68 patients (66%) in the Fraxiparine group and in 32/66 patients (48%) in the UFH group, and an increase in the thrombus size in 10/68 (15%) and 12/66 (18%), respectively. One symptomatic non-fatal pulmonary embolism and one major bleeding episode were observed in the UFH group. During a follow-up period of 3 months, two rethromboses had occurred in the UFH group and none in the Fraxiparine group. It is concluded that subcutaneous fixed dose Fraxiparine is safe and at least as effective as subcutaneous adjusted UFH in the treatment of deep vein thrombosis. 相似文献
3.
Serogroup specificity of Legionella pneumophila is related to lipopolysaccharide characteristics. 总被引:9,自引:3,他引:9
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We studied the lipopolysaccharide (LPS) of Legionella pneumophila and six other Legionella species to determine whether strain differences were apparent. The LPS was purified by a cold ethanol extraction procedure, and total carbohydrates represented 10 to 20% of LPS weight. 2-keto-3-deoxyoctonate represented 1 to 13% of the total carbohydrate present in the LPS. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis, all strains except L. dumoffi showed smooth-type LPS with multiple high-molecular-weight complexes. Proteinase K-treated, whole-cell lysates showed profiles similar to those of purified LPS. Each serogroup of L. pneumophila and each Legionella species had a distinct sodium dodecyl sulfate-polyacrylamide gel electrophoresis profile. L. pneumophila lipid A is antigenically related to the lipid A of Enterobacteriaceae. In immunoblot assays with the LPS of L. pneumophila serogroups 1 to 6 as antigens, serogroup-specific immune monkey sera recognized homologous purified LPS, but not the LPS of the five heterologous serogroups. These studies indicate that LPS composition may be a determinant of serogroup specificity as defined by the immunofluorescence-based serogrouping schema for L. pneumophila and other Legionella species. 相似文献
4.
Reduced mitochondrial coupling in vivo alters cellular energetics in aged mouse skeletal muscle 总被引:6,自引:1,他引:6
David J. Marcinek Kenneth A. Schenkman Wayne A. Ciesielski Donghoon Lee Kevin E. Conley 《The Journal of physiology》2005,569(2):467-473
The mitochondrial theory of ageing proposes that the accumulation of oxidative damage to mitochondria leads to mitochondrial dysfunction and tissue degeneration with age. However, no consensus has emerged regarding the effects of ageing on mitochondrial function, particularly for mitochondrial coupling (P/O). One of the main barriers to a better understanding of the effects of ageing on coupling has been the lack of in vivo approaches to measure P/O. We use optical and magnetic resonance spectroscopy to independently quantify mitochondrial ATP synthesis and O2 uptake to determine in vivo P/O. Resting ATP demand (equal to ATP synthesis) was lower in the skeletal muscle of 30-month-old C57Bl/6 mice compared to 7-month-old controls (21.9 ± 1.5 versus 13.6 ± 1.7 nmol ATP (g tissue)−1 s−1 , P = 0.01). In contrast, there was no difference in the resting rates of O2 uptake between the groups (5.4 ± 0.6 versus 8.4 ± 1.6 nmol O2 (g tissue)−1 s−1 ). These results indicate a nearly 50% reduction in the mitochondrial P/O in the aged animals (2.05 ± 0.07 versus 1.05 ± 0.36, P = 0.02). The higher resting ADP (30.8 ± 6.8 versus 58.0 ± 9.5 μmol g−1 , P = 0.05) and decreased energy charge (ATP/ADP) (274 ± 70 versus 84 ± 16, P = 0.03) in the aged mice is consistent with an impairment of oxidative ATP synthesis. Despite the reduced P/O, uncoupling protein 3 protein levels were not different in the muscles of the two groups. These results demonstrate reduced mitochondrial coupling in aged skeletal muscle that alters cellular metabolism and energetics. 相似文献
5.
Abstract: We report the first case of fatal anthrax meningoencephalitis in Hong Kong over the past 60 years. A 13 year-old boy presented with right lower quadrant pain, diarrhoea and progressive headache. Lumbar puncture yielded gram positive bacilli initially thought to be Bacillus cereus, a contaminant. He was treated with ampicillin and cefotaxime, but died 3 days after hospitalization. The organism isolated from blood and cerebrospinal fluid was later identified as Bacillus anthracis. 相似文献
6.
A prospective study of methylenetetrahydrofolate reductase and methionine synthase gene polymorphisms, and risk of colorectal adenoma 总被引:8,自引:2,他引:8
Chen J; Giovannucci E; Hankinson SE; Ma J; Willett WC; Spiegelman D; Kelsey KT; Hunter DJ 《Carcinogenesis》1998,19(12):2129-2132
We examined the relationship between a functional polymorphism (667C--
>T, ala-->val) of the methylenetetrahydrofolate reductase gene
(MTHFR) and the risk of colorectal adenomas in the prospective Nurses'
Health Study. Among 257 incident polyp cases and 713 controls, the MTHFR
val/val polymorphism [relative risk (RR) = 1.35, 95% confidence interval
(CI) 0.84-2.17] was not significantly associated with risk of adenomas.
This lack of association was observed for both small (RR = 1.36, 95% CI
0.76-2.45) and large (RR = 1.32, 95% CI 0.66-2.66) adenomas. Furthermore,
there was no significant interaction between this polymorphism and
consumption of either folate, methionine or alcohol. We also examined the
relationship of a newly identified polymorphism (asp919gly) of the
methionine synthase gene (MS) with the risk of colorectal adenomas in the
same population. The MS gly/gly polymorphism was also not significantly
associated with risk of colorectal adenomas (RR = 0.66, 95% CI 0.26-1.70).
These results, which need to be confirmed in other studies, suggest that
the MTHFR val/val polymorphism, which has been previously inversely
associated with risk of colorectal cancer, plays a role only in a late
stage (adenoma-- >carcinoma) of colorectal tumorigenesis, and/or may
protect against malignant transformation in the subset of benign adenomas,
which may progress to malignancy.
相似文献
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8.
Non-alcoholic fatty liver disease (NAFLD) often develops in concert with related metabolic diseases, such as obesity, dyslipidemia and insulin resistance. Prolonged lipid accumulation and inflammation can progress to non-alcoholic steatohepatitis (NASH). Although factors associated with the development of NAFLD are known, triggers for the progression of NAFLD to NASH are poorly understood. Recent findings published in The Journal of Pathology reveal the possible regulation of NASH progression by metabolites of the mevalonate pathway. Mevalonate can be converted into the isoprenoids farnesyldiphosphate (FPP) and geranylgeranyl diphosphate (GGPP). GGPP synthase (GGPPS), the enzyme that converts FPP to GGPP, is dysregulated in humans and mice during NASH. Both FPP and GGPP can be conjugated to proteins through prenylation, modifying protein function and localization. Deletion or knockdown of GGPPS favors FPP prenylation (farnesylation) and augments the function of liver kinase B1, an upstream kinase of AMP-activated protein kinase (AMPK). Despite increased AMPK activation, livers in Ggpps-deficient mice on a high-fat diet poorly oxidize lipids due to mitochondrial dysfunction. Although work from Liu et al provides evidence as to the potential importance of the prenylation portion of the mevalonate pathway during NAFLD, future studies are necessary to fully grasp any therapeutic or diagnostic potential. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
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10.
C Ciesielski D Marianos C Y Ou R Dumbaugh J Witte R Berkelman B Gooch G Myers C C Luo G Schochetman 《Annals of internal medicine》1992,116(10):798-805
OBJECTIVE: To determine if patients of a dentist with the acquired immunodeficiency syndrome (AIDS) became infected with human immunodeficiency virus (HIV) during their dental care and, if so, to identify possible mechanisms of transmission. DESIGN: Retrospective epidemiologic follow-up of the dentist, his office practice, and his former patients. SETTING: The practice of a dentist with AIDS in Florida. PARTICIPANTS: A dentist with AIDS, his health care providers and employees, and former patients of the dentist, including eight HIV-infected patients. MEASUREMENTS: Identification of risks for HIV transmission (if present), degree of genetic relatedness of the viruses, and identification of infection control and other office practices. RESULTS: Five of the eight HIV-infected patients had no confirmed exposures to HIV other than the dental practice and were infected with HIV strains that were closely related to those of the dentist. Each of the five had invasive dental procedures, done by the dentist after he was diagnosed with AIDS. Four of these five patients shared visit days (P greater than 0.2). Breaches in infection control and other dental office practices to explain these transmissions could not be identified. CONCLUSION: Although the specific incident that resulted in HIV transmission to these patients remains uncertain, the epidemiologic evidence supports direct dentist-to-patient transmission rather than a patient-to-patient route. 相似文献