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排序方式: 共有1345条查询结果,搜索用时 16 毫秒
91.
Kaplan C Mendiola R Ndjatou V Chapnick E Minkoff H 《American journal of obstetrics and gynecology》2003,188(5):1154-1155
OBJECTIVE: This study was undertaken to determine whether covering gowns reduce the rates of contamination of surgical scrubs. STUDY DESIGN: Seventy-five clinicians had pieces of fabric from clean scrubs attached to two areas of their scrub suits. Participants wore a covering garment when wearing scrub suits off of designated areas (n = 25), did not wear a covering garment (n = 25), or wore scrub suits outside the hospital (n = 25). Subsequently, the fabric was assessed with culture in enhanced broth media and blood agar. RESULTS: Although there was a trend toward lower rates of contamination in the group that did not wear a covering garment, the difference was not significant. At no point, and at neither site of fabric attachment, did those who wore a covering garment demonstrate any advantage in regard to levels or frequency of contamination. CONCLUSION: Wearing covering garments over scrub suits does not reduce rates of contamination. 相似文献
92.
Chaim W Horowitz S David JB Ingel F Evinson B Mazor M 《European journal of obstetrics, gynecology, and reproductive biology》2003,109(2):145-148
OBJECTIVE: Investigation of the clinical significance of Ureaplasma urealyticum and its biovars in the development of postpartum endometritis. STUDY DESIGN: Cervical swabs were cultured for U. urealyticum in women presenting endometritis. The positive U. urealyticum cultures (>10(5) cfu/ml) (study group) were compared with those from women without endometritis (control group). Anti-Ureaplasma antibodies were measured and U. urealyticum biovars were determined by polymerase chain reaction. RESULTS: There was no difference between the prevalence of U. urealyticum in the cervical swabs of both groups, however, the number of cfu per culture, showed a significant difference between study and control groups. Out of the culture positive endometritis patients 39% (26/67) had >10(5) cfu/ml compared to 17% of control patients (5/30) P=0.03. No significant disparity between both the groups was found in the prevalence of the parvo biovar (77% versus 71.5%, respectively). The difference in anti-Ureaplasma antibodies reached no statistical significance (30% versus 18% in study and control groups, respectively). CONCLUSIONS: The significant difference in U. urealyticum culture cfu between both groups suggests that U. urealyticum may play a role in the etiology of this infection. This involvement is dependent not only on the presence or absence of U. urealyticum in the culture, but on its colonization rate in the cervix (>10(5) cfu/ml). 相似文献
93.
94.
OBJECTIVE: Because nitric oxide related species have been found in the inflamed joints of patients with arthritis, we investigated whether protein nitrotyrosine (a marker of tissue exposure to peroxynitrite) is present in their synovial tissues. METHODS: Protein nitrotyrosine was detected immunohistochemically and by Western blot analysis. Synovial tissues removed surgically from 12 patients with rheumatoid arthritis (RA) (mean age 63.7 yrs) and 20 with osteoarthritis (OA) (mean age 66.6 yrs) were studied. RESULTS: Nitrated proteins were detected immunohistochemically in all of 18 tissues examined. Diffuse staining of the stroma was seen in all patients, with more extensive staining in RA than OA (p = 0.008). Intense staining was detected in some lymphocytes, but not in others, even within a single lymphoid aggregate. Neutrophils did not stain for nitrotyrosine. Vascular endothelial cells stained for nitrotyrosine but adjoining smooth muscle cells did not. Both cytoplasmic and nuclear staining was seen in macrophages, endothelial cells, and lymphocytes. Numerous bands of nitrated proteins were detected by Western blot analysis of 15 synovial tissue extracts. Inducible nitric oxide synthase (iNOS) was detected immunohistochemically in endothelial cells, macrophages, vascular smooth muscle cells, and synoviocytes. CONCLUSION: Nitrotyrosine-containing proteins were found in essentially all synovia from RA and OA patients. The most prominent site of nitration in all cases was the stroma. iNOS, the likely source of the nitrating species, was found in a variety of cell types. 相似文献
95.
Friedmann R Hamburger R Shulman C Yinnon AM Raveh D 《Diagnostic microbiology and infectious disease》2003,46(3):217-222
In order to determine bacterial distribution and antimicrobial susceptibility of urinary pathogens in a long-term-care-facility (LTCF), urine cultures were examined when clinically indicated. The LTCF consists of 286 beds, housing 931 residents during 32 months, in various wings; independent and frail residents (wing-A), nursing and demented patients (wing-B), and skilled-nursing patients (wing-C). A total of 1,401 positive urine cultures were obtained: E. coli was isolated significantly less often in wing-C than in wing-A (p = 0.02) and wing-B (p = 0.009). There was no significant difference in frequency of other organisms. Susceptibility of organisms decreased significantly from wing-C to wing-B (p < 0.05-0.001), and from wing-B to wing-A (p < 0.05-0.001). Susceptibility rates' decreased significantly over time in wing-B, less in wing-C and not at all in wing-A. In conclusion: When selecting empiric antibiotic therapy for serious urinary tract infection in a long-term-care resident, one should take into account the microbial environment of the individual patient's department. 相似文献
96.
Lev-Ran O Mohr R Uretzky G Pevni D Locker C Paz Y Shapira I 《The Annals of thoracic surgery》2003,75(1):88-92
BACKGROUND: The complementary graft of choice to the right coronary artery system in patients undergoing left-sided bilateral internal thoracic artery grafting has yet to be determined. Saphenous vein graft (SVG) was compared with right gastroepiploic artery (RGEA) as the supplemental conduit to the right coronary artery when left-sided bilateral internal thoracic artery grafting is implemented. METHODS: From April 1996 to July 1999, 234 patients underwent bilateral internal thoracic artery grafting to the left coronary system with RGEA grafted to the posterior descending artery (RGEA group). They were compared with 127 patients with left-sided bilateral internal thoracic artery in whom SVG was used for grafting the right coronary system (SVG group). RESULTS: Female sex (27% versus 14.5%), diabetic patients (40% versus 27%), emergency cases (21% versus 7.3%), and left main coronary artery disease (34% versus 23%) were more prevalent in the SVG group. Number of grafts per patient was higher in the SVG group (3.8 versus 3.5, p = 0.04). Thirty-day mortality was 3.9% in the SVG and 2.6% in the RGEA group (not significant). Occurrence of postoperative complications (myocardial infarctions, strokes, bleeding, and sternal infections) was similar. Return of angina was similar (1.6% versus 3.8% in the SVG and RGEA groups, respectively). Midterm follow-up (4 to 56 months) showed comparable 1-year and 4-year survival (Kaplan-Meier) for both groups (92.8% and 91.7% in the SVG group, and 94.7% and 88% in the RGEA group, respectively). CONCLUSIONS: In patients undergoing left-sided bilateral internal thoracic artery grafting, the use of RGEA for revascularization of the right coronary system does not confer clinical benefits over SVG after midterm follow-up. 相似文献
97.
98.
Gazit V Ben-Abraham R Pick CG Ben-Shlomo I Katz Y 《Pharmacology, biochemistry, and behavior》2003,75(4):795-799
We investigated whether structural central neural damage and long-term neurobehavioral deficits after L-cysteine (L-Cys) administration in mice is caused by hypoglycemia. Neonatal ICR mice were injected subcutaneously with L-Cys (0.5-1.5 mg/g body weight [BW]) or saline (control). Blood glucose was measured. At 50 days of age, mice were introduced individually into an eight-arm maze for evaluation of spatial memory (hippocampal-related behavior). Times for visiting all eight arms and number of entries until completion of the eight-arm visits (maze criteria) were measured. The test was repeated once daily for 5 days. In situ terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay was used for detection of brain damage. As early as 20 min and up to 2 h postinjection, animals treated with L-Cys doses higher than 1.2 mg/g BW developed hypoglycemia and looked ill. Several animals convulsed. Long-term survivors required more time, in a dose-dependent manner, to assimilate the structure of the maze, and animals treated with L-Cys (1.5 mg/g BW) exhibited TUNEL-positive changes in the hippocampal regions. All these changes were reversible by coadministration of glucose. We conclude that L-Cys injection can cause pronounced hypoglycemia associated with long-term neurobehavioral changes and central neural damage in mice. Since L-Cys is chemically different from the other excitatory amino acids (glutamate and aspartate), the long-reported L-Cys-mediated neurotoxicity may be connected to its hypoglycemic effect. 相似文献
99.
Administration of beta-phenylpyruvate at high concentrations reduces blood glucose levels and causes neurophysiological deterioration in insulin-deprived mice. We investigated whether beta-phenylpyruvate administration would cause long-term neurobehavioral and structural central neural damage in mice. Neonatal ICR mice were injected with beta-phenylpyruvate (0.5-2.5mg/g body weight (BW)) or saline (control). Blood glucose was measured. At 43 days of age, the animals were put on a 1-week regimen of restricted water supply, after which the mice were introduced into an eight-arm maze for evaluation of spatial-memory abilities (hippocampal-related behavior). Times for visiting all eight arms and number of entries until completion of the eight-arm visits (maze criteria) were measured. The test was repeated once daily for 5 days. TUNEL assay was used for detection of brain apoptosis. beta-Phenylpyruvate-treated animals (except the 0.5mg/g group) developed hypoglycemia. Treated mice required more time to assimilate the maze structure. Mice treated with 2.5mg/g beta-phenylpyruvate did not meet the maze criteria as compared with control (P<0.001) and suffered from necrotic changes in the hippocampal regions. The above-mentioned neurobehavioral damage was abrogated by coadministration of glucose. We conclude that beta-phenylpyruvate is able to produce necrotic neural damage accompanied by structurally related neurobehavioral dysfunction. Together with its hypoglycemic effect, these findings may explain the neurodegenerative process that occurs in phenylketonuria (PKU), insofar as beta-phenylpyruvate is a metabolite of phenylalanine known to accumulate in vast amounts in this inherited disorder. 相似文献
100.
NJ Hoogenraad JD Mitchell NA Don TM Sutherland AC Mc Leay 《Archives of disease in childhood》1980,55(4):292-295
The activity of urea cycle enzymes was assayed in duodenal biopsy specimens obtained from a female infant who presented with neonatal hyperammonaemia. All enzyme levels were normal except N-acetyl glutamate-dependent carbamyl phosphate synthetase 1 (CPS1) which was half the mean activity in normal control specimens. A similar deficiency of CPS1 was also shown in duodenal specimens from the patient's mother who became slightly symptomatic after relatively high protein meals and during pregnancy, and had spontaneously modified her diet to one with protein restriction. The patient is growing normally on a dietary regimen similar to that spontaneously adopted by her mother. Urea cycle enzyme activity in the duodenal biopsy material from the controls was similar to that found in the normal human liver and appears to have distinct advantages as a means of assaying for urea cycle defects in patients with hyperammonaemia and their relatives. 相似文献