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31.
Rejiba S Limam F Belhadj C Belhadj O Ben-Mahrez K 《Microbial drug resistance (Larchmont, N.Y.)》2002,8(1):9-13
Pseudomonas aeruginosa 802 was isolated at Rabta hospital in Tunis and was resistant to extended-spectrum cephalosporins and aztreonam. It produced a pI 7.6 extended-spectrum beta-lactamase (ESBL). The ESBL, named LBT 802, was purified to homogeneity by filtration on Sephadex G-75 followed by CM-Sepharose chromatography and high-performance liquid chromatography (HPLC) on a TSK-gel SP-5PW column. The LBT 802 enzyme had a molecular mass of 30 kDa. It showed a broad-substrate profile by hydrolyzing benzylpenicillin, ampicillin, cephalothin, cephaloridine, cefotaxime, ceftriaxone, and cefpirome but not ceftazidime, cefoxitin, imipenem, or aztreonam. The highest hydrolytic efficiency (Vmax/Km) was obtained for ampicillin, cephalothin, cephaloridine, and benzylpenicillin. Among extended-spectrum cephalosporins the best substrate was ceftriaxone followed by cefotaxime and cefpirome. LBT 802 activity was inhibited by clavulanic acid, sulbactam, imipenem, cefoxitin, and aztreonam. It showed its lowest Ki values for clavulanic acid, imipenem and sulbactam. 相似文献
32.
The use of the Arden gratings (AO contrast sensitivity system) in optometric practice is evaluated. A total of 320 patients presenting for eye examination were screened with the gratings. Sixty-four eyes (10%) gave abnormal grating scores although results from conventional examination techniques revealed no abnormality. Of the 110 abnormal eyes detected by routine examination techniques, 8 presented with normal grating scores, 6 with "borderline suspect" scores and 96 with abnormal scores. Used in isolation, the failure rate of the Arden gratings to detect ocular abnormality in the patient population was 1.3% and the "false positive" referral rate was 10%. 相似文献
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34.
Salam Bennouar Abdelghani Bachir Cherif Amel Kessira Djamel-Eddine Bennouar Samia Abdi 《Nutrition Clinique et Métabolisme》2021,35(2):144-151
Introduction/ObjectivesAcute kidney injury (AKI) and malnutrition are two complications commonly reported in severe forms of COVID-19, their combined effect on short-term mortality is, however, not yet investigated. The objective of this study is to determine both their individual and combined effects on short-term prognosis.Materials and methodsThis is a prospective, uni-centric study, including 247 severe COVID-19 patients, admitted between April 25th and June 20th, 2020, at the University Hospital of Blida. AKI was defined according to the KDIGO-2012 guidelines. Nutritional status was assessed using the Controlling Nutritional Status (CONUT) score. The association with in-hospital mortality was assessed using the Kaplan-Meier method and proportional Cox regression.ResultsAmong the 247 severely affected COVID-19 patients included in this study, 34.4% developed AKI, 30.4 and 1.2%, respectively, had moderate and severe CONUT scores, 17.7% worsened and progressed to a critical state and 26.7% did not survive. Both AKI and CONUT score were significantly associated with mortality in a dose-response manner (pLog-Rank < 0.0001). Their relative risks are respectively (HR = 3.25 CI 95% [1.99–5.3] and HR = 2.42 CI 95% [1.5–3.9], p < 0.0001). In multivariate analysis, the highest risk was observed for the AKI-CONUT-high combination (HR = 3.0, 95% CI [1.5–6.1], p = 0.002).ConclusionA possible synergistic interaction between AKI and CONUT score for COVID-19 short-term mortality has been highlighted. Monitoring of renal function associated with assessment of nutritional status should be performed routinely and systematically from the early stages of admission. 相似文献
35.
Marshburn PB Zhang J Bahrani-Mostafavi Z Matthews ML White J Hurst BS 《Molecular human reproduction》2005,11(11):809-815
Progesterone receptor (PR) variant mRNAs in human endometrium could encode proteins with the potential to alter progesterone action in states of normal and abnormal endometrial development. We have assessed the expression levels of mRNA for the wild-type PR and splice variants of PR mRNA lacking exon 4 (del-4 PR), exon 6 (del-6 PR), exons 4 and 6 (del-4&6 PR), and part of exon 4 (del-p4 PR) or part of exon 6 (del-p6 PR) in the human endometrium throughout menstrual cycle development. Eighty-eight endometrial specimens (47 proliferative, 41 secretory) were collected from patients undergoing hysterectomy for benign gynaecologic causes. Measurements by RT-PCR indicated that mRNAs for wild-type PR, and splice variants del-4 PR, del-6 PR, del-4&6 PR, del-p6 PR, and a novel del-p4 PR were detected in all endometrial specimens throughout the menstrual cycle. Higher levels of wild-type PR and all PR variant mRNAs were found in the early and mid-proliferative endometrial phases than in secretory endometrium. The relative expression of mRNA for all PR variants compared to wild-type PR mRNA, however, did not change through all stages of endometrial development. We, therefore, found no evidence of differential co-expression of the PR variants compared with wild-type PR during normal menstrual development. Future studies will determine if the expression profile of PR variant mRNAs will be different in the endometrium of patients with infertility, recurrent pregnancy loss, or endometrial adenocarcinoma. 相似文献
36.
Advances in the field of skull base surgery have dramatically reduced the mortality and morbidity of operations on the skull base. Nevertheless, cerebral ischemic events from compromised blood supply to areas of the brain still occur. Although arterial compromise is responsible for a majority of these events, the venous side of the circulation can also play a role in producing cerebral infarctions. A key area of cerebral venous drainage is at the junction of the transverse sinus, sigmoid sinus, and vein of Labbé. Absence of the transverse sinus with the outflow of the vein of Labbé limited to the sigmoid sinus puts these patients at an increased risk for venous infarcts when this area is manipulated during skull base surgery. We have studied 100 consecutive carotid angiograms performed on 50 individuals for carotid artery disease or to rule out aneurysms. We have found that 16.7% of individuals have one atretic transverse sinus. We discuss our results and the implications that they have in skull base surgery. It is our hope that a better understanding of the cerebral venous drainage patterns will help skull base surgeons avoid complications in the future. 相似文献
37.
Hurst K 《Health manpower management》1997,23(6):197-211
Multi-skilling has been the most enduring element of patient-focused care in the UK. A recent report from the Manchester University Health Service Management Unit (HSMU) extended the multi-skilling debate and offered a framework for changing National Health Service workforce policy along multi-skilling lines. Examines the main HSMU issues in the light of broader empirical and other evidence. Assesses the strengths, weaknesses, opportunities and threats to multi-skilling. Concludes that multi-skilling protagonists still face a number of challenges. 相似文献
38.
Ryan N Hurst K 《International journal of health care quality assurance incorporating Leadership in health services》1999,12(6-7):267-271
Owing to NHS managers' preponderance with financial issues, the present Government made improving the quality of health services a statutory requirement in 1997. In this article, one means of improving the quality of health services, clinical governance, is examined in detail before some issues related to its implementation are described. The Trust's A&E services, the context for interpreting and applying clinical governance, are briefly described before introducing a force-field analysis that demonstrates the different elements when changing services broadly and clinical governance specifically. The final section concentrates on implementing and improving clinical governance in A&E departments. 相似文献
39.
Many nonoperative therapies have been investigated for the treatment of Dupuytren's disease. These include needle fasciotomy, continuous slow skeletal traction, radiation, dimethyl sulfoxide, vitamin E, allopurinol, physical therapy, ultrasound therapy, steroid injections, radiation, interferon, splinting, and enzymatic fasciotomy. Most of these therapies have not proven to be clinically useful. However, recent investigation of enzymatic fasciotomy using collagenase injection has shown encouraging results. 相似文献
40.
BACKGROUND: Recent guidelines for those with acute low back pain have advocated early resumption of normal activity and increased physical activity. Little is known about the relationship between low back pain and physical activity, and on the impact of that relationship on the promotion of increased levels of physical activity within a general practice population. OBJECTIVES: We aimed to explore associations between factors that influence changes in physical activity and the way individuals perceive and behave with their low back pain, and the impact of those perceptions and behaviour on physical activity. METHODS: Twenty-seven informants were chosen using a purposive sample from a larger group of individuals who, because of their low back trouble, had been referred by their GPs to a community-based, single-blind, randomized controlled trial (RCT) at the University of York, which is evaluating the effectiveness and cost-effectiveness of a progressive exercise programme. Fifty-four interviews were conducted with this subgroup of the RCT; four informants were interviewed once, 19 twice and four of them three times. Interviews were transcribed and analysed using manual and computer-aided approaches. RESULTS: Physical activity was perceived as (i) activities of daily living, (ii) activities causing breathlessness that they went out of the way to do and (iii) more competitive-type activity. The avoidance of physical activity and fear of pain returning were the two main factors directly associated with informants' backs and changes in physical activity. These two factors hindered increases in physical activity, even though the majority of informants believed strongly that being physically active helped ease their low back pain. CONCLUSIONS: When advocating that individuals with acute low back pain return to or increase physical activity, it is important that clinicians identify avoidance of physical activity and/or fear of pain at the earliest stage in order to tailor advice and reassurance appropriately. If avoidance of activity and fear of pain is identified and clinicians want to encourage patients to take up and sustain increased physical activity, they should explore issues of fear of pain, and avoidance of and confidence to do physical activities, in addition to other factors influencing physical activity. 相似文献