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排序方式: 共有236条查询结果,搜索用时 15 毫秒
191.
Rates of carriage of methicillin-resistant and methicillin-susceptible Staphylococcus aureus in an outpatient population. 总被引:2,自引:0,他引:2
Julie Kenner Tasha O'Connor Nicholas Piantanida Joel Fishbain Bardwell Eberly Helen Viscount Catherine Uyehara Duane Hospenthal 《Infection control and hospital epidemiology》2003,24(6):439-444
OBJECTIVES: To assess the prevalence of and the clinical features associated with asymptomatic Staphylococcus aureus colonization in a healthy outpatient population, and to compare the characteristics of colonizing methicillin-resistant S. aureus (MRSA) strains with those of strains causing infection in our community and hospital. SETTING: Outpatient military clinics. METHODS: Specimens were obtained from the nares, pharynx, and axillae of 404 outpatients, and a questionnaire was administered to obtain demographic and risk factor information. MRSA strains were typed by pulsed-field gel electrophoresis (PFGE) and evaluated for antibiotic susceptibility. Antibiograms of study MRSA strains were compared with those of MRSA strains causing clinical illness during the same time period. RESULTS: Methicillin-susceptible S. aureus (MSSA) colonization was present in 153 (38%) of the 404 asymptomatic outpatients, and MRSA colonization was present in 8 (2%). Detection of colonization was highest from the nares. No clinical risk factor was significantly associated with MRSA colonization; however, a tendency was noted for MRSA to be more common in men and in those who were older or who had been recently hospitalized. All colonizing MRSA strains had unique patterns on PFGE. In contrast to strains responsible for hospital infections, most colonizing isolates of MRSA were susceptible to oral antibiotics. CONCLUSIONS: MRSA and MSSA colonization is common in our outpatient population. Colonization is best detected by nares cultures and most carriers of MRSA are without apparent predisposing risk factors for acquisition. Colonizing isolates of MRSA are heterogeneous and, unlike nosocomial isolates, often retain susceptibility to other non-beta-lactam antibiotics. 相似文献
192.
DP Foley MB MRCPI D Keane MB MRCPI PW Serruys MD FESC 《International journal of clinical practice》1995,49(1):7-15
SUMMARY Luminal renarrowing after successful coronary angioplasty is now recognised as a continuously distributed process which is determined largely by the extent of luminal increase achieved at angioplasty. In this study an alternative analytical approach is applied to determine whether luminal renarrowing following coronary intervention is related to the mechanism of luminal increase (ie by balloon, by atherectomy, by a self-expanding stainless steel mesh stent, or by a balloon-expandable tantalum coil stent). The results confirm the known proportional relationship between luminal renarrowing during follow-up and luminal improvement at intervention, regardless of the device used. However, significant differences were observed between the devices, which may reflect device-specific characteristics of the hyperplastic response to vessel injury and may have clinical implications. 相似文献
193.
High Imminent Vertebral Fracture Risk in Subjects With COPD With a Prevalent or Incident Vertebral Fracture 下载免费PDF全文
Mayke J van Dort Piet Geusens Johanna HM Driessen Elisabeth APM Romme Frank WJM Smeenk Emiel FM Wouters Joop PW van den Bergh 《Journal of bone and mineral research》2018,33(7):1233-1241
Subjects with chronic obstructive pulmonary disease (COPD) have an increased risk of vertebral fractures (VFs); however, VF incidence is largely unknown. Therefore, the aim of our study was to determine the incidence of new and/or worsening VF in subjects with COPD. Smokers and subjects with COPD (GOLD II–IV) from the ECLIPSE study with complete set of chest CT scans (baseline and 1‐ and 3‐year follow‐up) to evaluate vertebrae T1 down to L1 were included. If a VF was diagnosed on the last scan, detailed VF assessment of the previous scans was performed. VFs were scored according to the method of Genant as mild, moderate, or severe. Main outcome measure was the cumulative incidence of new and/or worsening VF at subject level, within 1 and 3 years. Of 1239 subjects (mean age 61 years, 757 males [61%], 999 subjects with COPD), 253 (20.5%) had ≥1 prevalent VF. The cumulative incidence of VFs was 10.1% within 1 year and 24.0% within 3 years. After adjustment for age, sex, body mass index (BMI), pack‐years, and smoking status, prevalence and incidence were similar between smokers and COPD GOLD stages. Within 1 year, 29.2% of the subjects with a prevalent VF had an incident VF, compared with 5.1% in absence of prevalent VF (hazard ratio [HR] = 5.1; 95% confidence interval [CI] 3.6–7.4) and 58.5% versus 15.0% within 3 years (HR = 3.6; 95% CI 2.9–4.6). The incidence of VF was higher with increasing number and severity of prevalent VFs. Among subjects having an incident VF within the first year, 57.3% had a subsequent VF within the next 2 years. In this study, more than half of the smokers and subjects with COPD with a prevalent VF or an incident VF within the first year sustained a subsequent VF within 3 years. The 3‐year risk was even higher in the presence of multiple or severe prevalent VFs. © 2018 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals Inc. 相似文献
194.
Antibody ligation of CD9 modifies production of myeloid cells in long- term cultures 总被引:2,自引:3,他引:2
Oritani K; Wu X; Medina K; Hudson J; Miyake K; Gimble JM; Burstein SA; Kincade PW 《Blood》1996,87(6):2252-2261
The KMC8.8 monoclonal antibody was made by immunizing rats with the BMS2 stromal cell clone, and was selected for further study because its ability to inhibit production of myeloid cells in Dexter cultures but not that of lymphoid cells in Whitlock-Witte cultures. The influence on myeloid progenitors might have been indirect, since the antibody did not prevent responsiveness to colony-stimulating factors in semisolid agar cultures. Furthermore, there was no inhibition, and some augmentation, of cell production when the antibody was added to established Dexter cultures. A cDNA clone that encoded the KMC8.8- recognized molecule was isolated by expression cloning and found to be identical in sequence to a previously published murine CD9 homologue. The antibody and cDNA clone were used to establish that CD9 is expressed by stromal cells, megakaryocytes, platelets, myeloid cells, and subpopulations of mature lymphocytes in mice. Treatment with the KMC8.8/CD9 antibody slightly augmented adhesion between myeloid cells and stromal cells, consistent with previous reports that this member of the tetraspan family of proteins can transmit proadhesive signals to human platelets and lymphoid cells. CD9 might participate in cell-cell interactions critical for correct orientation and movement of maturing myeloid cells in bone marrow. 相似文献
195.
The tenfold increase in red cell 2,3-diphosphoglycerate (DPG) concentration that occurs during the first 5 days of life in lambs is an important adaptation to extrauterine life. In lambs, DPG reduces hemoglobin oxygen affinity by the Bohr effect. Our data on 10 neonatal lambs suggest that the biochemical mechanism underlying this DPG increase involves the following: (1) a rise in plasma glucose from 40 to 100 mg/dl in the first 48 hr of life, which allows for increased glucose consumption in the highly glucose-permeable neonatal RBC; (2) a transitory rise in blood pH begins at birth, peaks at about 20 hr, and falls slightly; (3) the pH increase coincides with a threefold increase in RBC fructose-1,6-diphosphate (FDP) concentration due, we believe, to pH activation of phosphofructokinase; (4) glycolytic intermediates after the glyceraldehyde-3-phosphate dehydrogenase (GAPD) step do not rise in the first 24 hr of life, possibly due to insufficient inorganic phosphate (Pi), a substrate of GAPD; (5) plasma Pi increases from about 7 mg/dl at birth to 11 mg/dl at 72 hr, activates the GAPD, and FDP levels decline; and (6) the in vitro activity of the DPG synthetic enzyme, DPG mutase, is increased 12-fold in neonatal compared to adult RBC. We conclude that the postnatal rise in DPG is explained at least in part by the sequential effects of these metabolic changes. 相似文献
196.
197.
ML Davenport N Punyasavatsut D Gunther L Savendahl PW Stewart 《Acta paediatrica (Oslo, Norway : 1992)》1999,88(S433):118-121
The purpose of this study was to determine the pattern of early growth in girls with Turner syndrome. Analysis was performed on a total of 464 longitudinal measurements of height, obtained from birth to 8 years of age from 37 girls with Turner syndrome who did not have significant cardiac disease or autosomal abnormalities. All data were obtained prior to the initiation of any hormonal therapy. Mean height SDS fell from -0.5 at birth to -1.5 at age 1 year and -1.8 at age 1.5 years. Growth curves fitted using the first two components of the infancy-childhood-puberty model of growth revealed that growth failure was due to (a) mild growth retardation in utero , (b) slow growth during infancy, (c) delayed onset of the childhood component of growth and (d) slow growth during childhood. Physicians should consider the diagnosis of Turner syndrome in any girl with an unexplained failure to thrive or with short stature, even during the first 2 years of life. 相似文献
198.
199.
Serial ultrasound (US) examinations of six cases of fetal multicystic dysplastic kidney were reviewed. In all cases the diagnosis was confirmed by pathologic or neonatal radiologic examination. The in utero appearance on US scans of multicystic dysplastic kidneys sometimes changed dramatically. Furthermore, all of the multicystic dysplastic kidneys changed in size: four enlarged, one shrank, and one initially enlarged and later shrank. Radiologic and laboratory data suggest that multicystic dysplastic kidneys may have the capacity for glomerular filtration. The change in size and appearance of fetal multicystic dysplastic kidneys may result from this residual renal function. 相似文献
200.
Comparison of 125I-fibrinogen kinetics and fibrinopeptide A in patients with disseminated neoplasias
To provide more information on the pathways of fibrinogen catabolism in generalized cancer, the effect of heparin on fibrinopeptide A (fpA) and on 125I-fibrinogen kinetics was studied in 15 patients with disseminated neoplasia. Three patients had evidence of venous thrombosis and in 2 additional patients a low fibrinogen level together with increased amounts of FDP/fdp and a positive ethanol test indicated disseminated intravascular coagulation (DIC). The plasma levels of fpA were grossly elevated (4.6--20, mean 11.4 ng/ml, normal values 1.01 +/- 0.45 ng/ml) in patients with thrombosis or DIC, and normal to grossly elevated (0.4--10.4, mean 6.1 ng/ml) in the other patients. Intravenous heparin bolus lowered the fpA level in 11/11 patients, and continuous heparin treatment led to an impressive suppression or complete normalization of the plasma fpA in 5/6 patients. This finding is thought to reflect heparin suppression of thrombin activity on fibrinogen. In some cases, the fpA fall after heparin bolus was slow and/or incomplete, suggesting fpA generation at sites not easily accessible to heparin or insufficient heparin dosage. The 125I- fibrinogen kinetics were characterized by a significantly shorter half- life (t1/2: 2.5 days), increased catabolic rate constant (j: 0.44 days- 1), and increased absolute turnover (68.9 mg fibrinogen/kg/day) as compared to 4 normal subjects (t1/2: 4.2 days; j: 0.26 days-1; turnover 21.7 mg fibrinogen/kg/day). As estimated from the fpA generation rates, intravascular thrombin action on fibrinogen contributed only in minor part to increase the turnover of 125I-fibrinogen. In particular, the turnover was greatly accelerated in heparin-treated patients despite impressive suppression or normalization of the fpA levels in 5/6 cases. 相似文献