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排序方式: 共有1299条查询结果,搜索用时 15 毫秒
991.
992.
Fuentes DE Navarro CA Tantaleán JC Araya MA Saavedra CP Pérez JM Calderón IL Youderian PA Mora GC Vásquez CC 《Research in microbiology》2005,156(4):472-477
We have characterized a natural isolate of Staphylococcus epidermidis resistant to heavy metals that carries a small 2391-bp plasmid, pSepCH, encoding the qacC gene. The S. epidermidis qacC gene confers resistance to a number of beta-lactam antibiotics and to ethidium bromide in its natural host and in Escherichia coli K12 and Salmonella enterica sv. Typhimurium. This is the first communication of a small multidrug resistance (SMR) pump involved in resistance to beta-lactam antibiotics. Experiments using tolC, ompW and ompD mutant strains of S. Typhimurium demonstrated that the beta-lactam antibiotic resistance conferred by this pump does not depend on these outer membrane proteins. 相似文献
993.
Z. Rázga B. Iványi J. Ormos N. Zidar D. Ferluga S. Sonkodi 《Virchows Archiv : an international journal of pathology》1996,429(4-5):275-281
Arteriolosclerosis frequently occurs in IgA nephritis (IgAN), and it is the hallmark of benign nephrosclerosis (BNS). The quantitative ultrastructure of juxtaglomerular arterioles is not known in these disorders. We examined afferent and efferent arterioles in renal biopsies from 25 adult patients with IgAN (hypertension at biopsy: 14 patients) and 9 patients with BNS. Six agematched living renal transplant donors acted as controls. A systematic independent sample of profiles was obtained in thin sections taken at predetermined levels. The thickness of the media (myomedial cells plus the matrix) and the thickness of the medial matrix were estimated stereologically. From these estimates, the matrix/myomedia ratio was calculated. In IgAN with normotension or hypertension, the afferent media and its compartments did not exhibit significant thickening compared with the controls, whereas in BNS the afferent media and its layers were markedly and significantly thickened. The efferent media in IgAN and BNS displayed mild and significant thickening, with significant thickening of the matrix in BNS and IgAN with normotension. The matrix/myomedia ratio was not altered significantly in any group. The results indicate that the afferent arterioles are not the main sites of IgAN-related arteriolosclerosis, that arteriolosclerosis in IgAN and arteriolosclerosis in BNS are different lesions, and that increased efferent arteriolar thickness, demonstrated here for the first time in IgAN and BNS, might be a manifestation of angiotensin II-mediated autoregulatory efferent vasoconstriction exerted to maintain the glomerular filtration pressure. 相似文献
994.
Rakonczay Z Takács T Iványi B Mándi Y Pápai G Boros I Varga I Jost K Lonovics J 《Clinical and experimental medicine》2002,2(2):89-97
Heat shock proteins (HSPs) are necessary in the synthesis, degradation, folding, transport, and translocation of different
proteins. It is well known that the increased expression of HSPs may have a protective effect against cerulein-induced pancreatitis
in rats or against choline-deficient ethionine-supplemented diet model pancreatitis in mice. The aim of this study was to
investigate the potential effects of HSP preinduction by cold or hot water immersion on trypsin-induced acute pancreatitis
in rats. Trypsin was injected into the interlobular tissue of the duodenal part of the pancreas at the peak level of HSP synthesis,
as determined by Western blot analysis. The rats were sacrificed by exsanguination through the abdominal aorta 6 h after the
trypsin injection. The serum amylase activity, the tumor necrosis factor-α, interleukin-1, and interleukin-6 levels, the pancreatic
weight/body weight ratio, and the pancreatic contents of DNA, protein, amylase, lipase, and trypsinogen were measured. A biopsy
for histology was taken. Hot water immersion significantly elevated the HSP72 expression, while cold water immersion significantly
increased the HSP60 expression. Cold water immersion pretreatment ameliorated the pancreatic edema in trypsin-induced pancreatitis,
however this was not due to the HSP60. Hot water immersion pretreatment did not have any effect on the measured parameters
in trypsin-induced pancreatitis. The findings suggest that the induction of HSP60 or HSP72 are not enough to protect rats
against the early phase of this localized necrohemorrhagic pancreatitis model.
Received: 8 October 2001 / Accepted: 26 March 2002 相似文献
995.
996.
Barros Camargo Luis Quintero Marzola Iván Darío Cárdenas Gómez Juan Carlos Mendoza Daza Leidy Tatiana Quintana Pájaro Loraine 《International urology and nephrology》2020,52(7):1403-1404
International Urology and Nephrology - 相似文献
997.
J Iványi 《Therapie der Gegenwart》1969,108(2):270-291
998.
999.
1000.
Díaz P Pedreira J Sánchez-Andrade R Suárez JL Arias MS Francisco I Fernández G Díez-Baños P Morrondo P Paz-Silva A 《Parasitology research》2007,101(2):339-342
From March 2001 to February 2004, 724 faecal samples of cattle under field conditions were collected in 121 farms from Lugo
(NW Spain), an area with oceanic climate. The risk periods of infection by Paramphistomum trematoda in cattle was assessed by analyzing the prevalence of paramphistomosis, egg-output and climatic data. A significantly
higher percentage of cattle passing trematode eggs by faeces was recorded firstly in September and secondly in March. The
greatest numbers of eggs were achieved in May. Finally, the individual average prevalence was 19% and 36% of the farms had
Calicophoron daubneyi-positive cattle. We conclude that the periods of high risk for C. daubneyi infection in areas with oceanic climate are those following periods with elevated rainfall, which occurs in May–June and
November–December in these areas. Appropriate measures for reducing the risk for paramphistomosis are needed and the administration
of chemotherapy with efficient anthelmintic in June and in November is strongly recommended. 相似文献