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排序方式: 共有418条查询结果,搜索用时 15 毫秒
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2.
Social-psychological predictors of self-reported actual and intended physical activity in a university workforce sample. 总被引:2,自引:1,他引:1
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![点击此处可从《British journal of sports medicine》网站下载免费的PDF全文](/ch/ext_images/free.gif)
This study investigated the social-psychological predictors of self-reported actual and intended physical activity in a university workforce sample. Based on the 'Theory of Planned Behaviour', but with additional variables of benefits, barriers and self-efficacy, it was found that both intended and actual activity could be predicted but only when strenuous activity was considered. In addition, the predictors were different for men and women. Specifically, the best predictors of intention to exercise were attitude, perceived control, benefits and self-efficacy for women, but only attitude for men. Predicting self-reported strenuous activity for women were intention and self-efficacy, and for men intention and attitude. Theoretical and practical implications for attitude research and exercise promotion are discussed. 相似文献
3.
Characterization of clinical isolates of Klebsiella pneumoniae from 19 laboratories using the National Committee for Clinical Laboratory Standards extended-spectrum beta-lactamase detection methods 总被引:4,自引:0,他引:4
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![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Steward CD Rasheed JK Hubert SK Biddle JW Raney PM Anderson GJ Williams PP Brittain KL Oliver A McGowan JE Tenover FC 《Journal of clinical microbiology》2001,39(8):2864-2872
Extended-spectrum beta-lactamases (ESBLs) are enzymes found in gram-negative bacilli that mediate resistance to extended-spectrum cephalosporins and aztreonam. In 1999, the National Committee for Clinical Laboratory Standards (NCCLS) published methods for screening and confirming the presence of ESBLs in Klebsiella pneumoniae, Klebsiella oxytoca, and Escherichia coli. To evaluate the confirmation protocol, we tested 139 isolates of K. pneumoniae that were sent to Project ICARE (Intensive Care Antimicrobial Resistance Epidemiology) from 19 hospitals in 11 U.S. states. Each isolate met the NCCLS screening criteria for potential ESBL producers (ceftazidime [CAZ] or cefotaxime [CTX] MICs were > or =2 microg/ml for all isolates). Initially, 117 (84%) isolates demonstrated a clavulanic acid (CA) effect by disk diffusion (i.e., an increase in CAZ or CTX zone diameters of > or =5 mm in the presence of CA), and 114 (82%) demonstrated a CA effect by broth microdilution (reduction of CAZ or CTX MICs by > or =3 dilutions). For five isolates, a CA effect could not be determined initially by broth microdilution because of off-scale CAZ results. However, a CA effect was observed in two of these isolates by testing cefepime and cefepime plus CA. The cefoxitin MICs for 23 isolates that failed to show a CA effect by broth microdilution were > or =32 microg/ml, suggesting either the presence of an AmpC-type beta-lactamase or porin changes that could mask a CA effect. By isoelectric focusing (IEF), 7 of the 23 isolates contained a beta-lactamase with a pI of > or =8.3 suggestive of an AmpC-type beta-lactamase; 6 of the 7 isolates were shown by PCR to contain both ampC-type and bla(OXA) genes. The IEF profiles of the remaining 16 isolates showed a variety of beta-lactamase bands, all of which had pIs of < or =7.5. All 16 isolates were negative by PCR with multiple primer sets for ampC-type, bla(OXA), and bla(CTX-M) genes. In summary, 83.5% of the K. pneumoniae isolates that were identified initially as presumptive ESBL producers were positive for a CA effect, while 5.0% contained beta-lactamases that likely masked the CA effect. The remaining 11.5% of the isolates studied contained beta-lactamases that did not demonstrate a CA effect. An algorithm based on phenotypic analyses is suggested for evaluation of such isolates. 相似文献
4.
Lectin characterization of gonococci from an outbreak caused by penicillin-resistant Neisseria gonorrhoeae. 总被引:1,自引:0,他引:1
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![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
W O Schalla R J Rice J W Biddle Y Jeanlouis S A Larsen W L Whittington 《Journal of clinical microbiology》1985,22(4):481-483
A total of 40 Neisseria gonorrhoeae isolates, representing 19 penicillin-resistant isolates (from 8 heterosexual patients and 11 homosexual patients) and 21 penicillin-susceptible isolates (from 15 heterosexual patients and 6 homosexual patients) and obtained from the same geographic area, were examined. Lectin agglutination patterns were based on the reactivity of the isolates with the following 14 lectins: concanavalin A, Lens culinaris, Trichosanthes kinlowii, Griffonia simplicifolia I, Arachis hypogeae (peanut agglutinin), Glycine max (soybean agglutinin), Dolichos bifloris, Griffonia simplicifolia II, Solanum tuberosum (potato starch agglutinin), Triticum vulgaris (wheat germ agglutinin), Limax flavus, Phaseolus vulgaris, Ulex europaeus I, and Lotus tetragonolobus. All isolates were serotyped with monoclonal antibodies specific for gonococcal outer membrane protein I and auxotyped, and the plasmid content was determined. Resistant patient isolates were selected for their decreased penicillin susceptibility, and control isolates were selected for their penicillin susceptibility. Even though the patient isolates demonstrated resistance to penicillin, no phenotypic differences in lectin-grouping patterns were demonstrated between the two study groups; i.e., two predominant lectin groups were observed. No resistance-associated plasmids were detected. All patient isolates were serogroup IB (serovars IB-1, IB-2, and IB-4), whereas 12 of 21 control isolates were serogroup IA (P less than 0.05). Isolates obtained from different anatomical sites in the same patient (cervical and rectal) agreed with regard to lectin patterns and serovars but not auxotypes. 相似文献
5.
Factors influencing help seeking in mentally distressed young adults: a cross-sectional survey.
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![点击此处可从《The British journal of general practice》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Lucy Biddle David Gunnell Debbie Sharp Jenny L Donovan 《The British journal of general practice》2004,54(501):248-253
BACKGROUND: Young adults, especially men, are among those least likely to consult healthcare professionals when mentally distressed or suicidal. AIMS: To investigate the help-seeking behaviours of mentally distressed young adults. Design of study: Cross-sectional survey. SETTING: Bristol and surrounding areas, including inner-city, suburban and urban locations. METHOD: A questionnaire was sent to a sample of 3004 young adults aged 16-24 years. This assessed probable mental disorder (using the 12-item general health questionnaire [GHQ-12]), suicidal thoughts (GHQ-28 suicide subscale), and help-seeking behaviours. RESULTS: Most responders who were assessed as having probable mental disorders (GHQ "cases") had not sought help. Help seeking was more common in female GHQ cases than male cases (34.8% and 21.8%,respectively; P = 0.003) and women with suicidal thoughts more commonly sought help than men with suicidal thoughts (41.6% and 30.9%, respectively; P = 0.15). Small proportions of male and female GHQ cases (7.5% and 8.9%, respectively; P = 0.6), and less than one in five responders with suicidal thoughts, had consulted a general practitioner. In more female than male cases, help was sought from family and friends (30.7% and 18.4%, respectively; P = 0.004). GHQ score was the strongest predictor of help seeking. Men had a higher threshold of severity at which they would seek help than women. Recent experience of suicidal thoughts appeared to be a stronger predictor of formal help seeking in mentally distressed women than mentally distressed men. CONCLUSION: Distressed young adults are reluctant to seek help. Men are particularly unlikely to do so unless severely distressed and tend not to seek lay support. Sex differences in help seeking may be important in understanding the high suicide rate for men. 相似文献
6.
Scattered reports, both clinical and experimental, have been accumulating in the past 20 years indicating that true seizures may, indeed, originate from the brain stem and its immediate connections. Four cases are reported that give further strong presumptive evidence that this is so. All the seizures were confined to axial structures (face, tongue, palate, pharynx, diaphragm, and abdomen), and in one case each seizure had an identical "Jacksonian march." The phenomena were documented by 16-mm motion pictures, brain stem signs, and electroencephalography. The EEG consisted of periods of burst activity followed by relative interictal electrocerebral silence. 相似文献
7.
Konstantin H Dragnev W Jeffrey Petty Sumit Shah Adrian Biddle Neil B Desai Vincent Memoli James R Rigas Ethan Dmitrovsky 《Journal of clinical oncology》2005,23(34):8757-8764
PURPOSE: The epidermal growth factor receptor (EGFR) and cyclin D1 are overexpressed in lung carcinogenesis. The rexinoid, bexarotene, represses cyclin D1 and EGFR expression in vitro. It was hypothesized that combining bexarotene with the EGFR inhibitor, erlotinib, would augment clinical activity. PATIENTS AND METHODS: In vitro studies and a phase I clinical trial were performed. Twenty-four patients with advanced aerodigestive tract cancers were enrolled; 79% had non-small-cell lung cancer (NSCLC). The primary objective was to determine the maximum-tolerated dose. Clinical activity was a secondary objective. RESULTS: Combining erlotinib with bexarotene enhanced growth suppression in vitro compared with each single-agent treatment. This cooperatively repressed cyclin D1 expression. Clinically, the most frequent toxicities were mild hypertriglyceridemia and skin rash. Two serious treatment-related adverse events occurred (creatine phosphokinase elevation attributed to antilipid therapy and a case of generalized pain). Five objective responses (four partial and one minor) were observed in NSCLC patients. Responses were observed in males and smokers. EGFR sequence analyses did not reveal activating mutations in tumors from assessable responding patients. Median time to progression was 2.0 months; overall survival time was 14.1 months; and 1-year survival rate was 73.8%. CONCLUSION: The recommended phase II doses are erlotinib 150 mg/d and bexarotene 400 mg/m2/d orally. These agents can be administered in combination at the recommended single-agent doses without added toxicity. Overall survival and clinical features of responding patients differ from prior reports of single-agent erlotinib treatment. These findings are encouraging and warrant further investigation of this regimen. 相似文献
8.
BackgroundJudging depth is important in surgery. Although there are several cues that permit depth perception, stereoacuity has been singled out as a possible predictor of surgical ability. However, it is not clear whether high-grade stereoacuity is necessary for a career in surgery. To help answer this, we aimed to evaluate stereoacuities in practising surgeons across a range of surgical specialities.MethodsWe recorded stereoacuity values on 66 surgeons working at a London teaching hospital using three standard stereotests: Titmus, TNO and Frisby. There were 36 Trainees and 30 Consultants, covering 12 surgical specialities.ResultsMedian stereoacuities (with range) for the whole group were: 40 s arc on Titmus (40–800), 30 s arc on TNO (15–480) and 20 s arc on Frisby (20–600). Four surgeons had no recordable stereoacuity on TNO, and one was also unrecordable on Titmus. Three of these four were Consultants. Depending on the test used, high-grade stereopsis was found in 74%–83% of surgeons while reduced stereopsis was found in 2%–14% of surgeons.ConclusionWhile we found that most surgeons in current NHS practice have high-grade stereoacuity, there are also surgeons with reduced stereopsis and some with no stereopsis. The findings do not therefore support the assertion that high-grade stereopsis is a universal requirement for a career in surgery. It would be difficult to justify setting a stereoacuity criterion for entrance into a surgical training programme. 相似文献
9.
Phenotypic plasticity and epithelial‐to‐mesenchymal transition in the behaviour and therapeutic response of oral squamous cell carcinoma
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![点击此处可从《Journal of oral pathology & medicine》网站下载免费的PDF全文](/ch/ext_images/free.gif)
It is increasingly recognised that phenotypic plasticity, apparently driven by epigenetic mechanisms, plays a key role in tumour behaviour and markedly influences the important processes of therapeutic survival and metastasis. An important source of plasticity in malignancy is epithelial‐to‐mesenchymal transition (EMT), a common epigenetically controlled event that results in transition of malignant cells between different phenotypic states that confer motility and enhance survival. In this review, we discuss the importance of phenotypic plasticity and its contribution to cellular heterogeneity in oral squamous cell carcinoma with emphasis on aspects of drug resistance and EMT. 相似文献
10.
C K Nair W P Biddle A Kaneshige C Cook K Ryschon M H Sketch 《American heart journal》1992,124(1):154-159
Limited data are available on mitral valve replacement in the elderly patient. Therefore we report our 10-year experience including predictors of perioperative mortality and subsequent long-term cardiac mortality in elderly patients with mitral valve replacement compared to younger patients. Of the 126 consecutive patients with mitral valve replacement, 26 were older (77 +/- 4, group 1) and 100 were younger (62 +/- 9, group 2) than 70 years. Bioprostheses were used more frequently in patients in group 1 (65% vs 7%, p less than 0.0001). Of the 21 clinical, ECG, hemodynamic, and angiographic variables studied, patients in group 1 had higher pulmonary artery systolic pressure (57 +/- 15 vs 48 +/- 19, p less than 0.05), fascicular block on ECGs (70% vs 33%, p less than 0.005), and greater pump time on cardiopulmonary bypass (160 +/- 75 vs 120 +/- 50 minutes, p less than 0.025). A trend toward a higher perioperative mortality rate was also seen in group 1 (27% vs 12%, p = 0.058). Predictors of perioperative mortality by multivariate analysis were the presence of aortic calcification and prolonged pump time on cardiopulmonary bypass in group 1 and coronary artery disease, female sex, elevated mean pulmonary artery pressure, and postoperative complete atrioventricular block in group 2. During a mean 4-year follow-up period, cardiac mortality and total mortality rates were 42% and 54%, respectively, for group 1 compared to 24% and 35%, respectively, for group 2.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献