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981.
Losses in follow-up that are biased with respect to outcome invalidate the results. There are many ways of dealing with non-response in follow-up studies. Three separate methods were used to investigate a potential bias in a mail survey of 2471 disabled people. At a response rate of 84%, the non-respondents were significantly different from the respondents with respect to the outcome, return to work and vocational training. The success rate in terms of the outcome was negatively related to the number of reminders. Significant differences were found in response rates according to age, social class, impairments, previous employment record, and completion of rehabilitation courses. There is no safe level of response rates below 100%. However small the non-response, a possible bias as a result of it must be investigated. 相似文献
982.
Fatimi SH Sheikh S Ali AA 《Journal of the College of Physicians and Surgeons--Pakistan : JCPSP》2006,16(4):309-310
Esophageal perforation remains an important thoracic emergency. Aggressive operative therapy remains the mainstay for treatment. A case of esophageal perforation, consequent upon impacted food bolus, is presented. An 80 years old female, with multiple comorbidities, presented with dysphagia and right sided chest pain, who had a distal esophageal tear, secondary to accidental meat ball ingestion. Rigid esophagoscopy showed complete occlusion of the distal esophagus with a meat ball. Right thoracotomy was performed, which showed perforated esophagus with large meat ball protruding from it. Endoscopic removal of the food particles was done, and the rupture was repaired using a pleural flap. The entire postoperative stay was uneventful and the patient was discharged on the ninth post-operative day. 相似文献
983.
Sheikh K Porter J Kielmann K Rangan S 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2006,100(4):312-320
The private medical sector is an important and rapidly growing source of health care in India. Private medical providers (PMP) are a diverse group, known to be poorly regulated by government policies and variable in the quality of services provided. Studies of their practices have documented inappropriate prescribing as well as violation of ethical guidelines on patient care. However, despite the critique that inequitable services characterise the private medical sector, PMPs remain important and preferred providers of primary care. This paper argues that their greater involvement in the public health framework is imperative to addressing the goal of health equity. Through a review of two research studies conducted in Pune, India, to examine the role of PMPs in tuberculosis (TB) and HIV/AIDS care, the themes of equity and access arising in private sector delivery of care for TB and HIV/AIDS are explored and the future policy directions for involving PMPs in public health programmes are highlighted. The paper concludes that public-private partnerships can enhance continuity of care for patients with TB and HIV/AIDS and argues that interventions to involve PMPs must be supported by appropriate research, along with political commitment and leadership from both public and private sectors. 相似文献
984.
Selenium is an essential micronutrient that is currently being tested for prostate cancer chemoprevention. In spite of its significant promise as a chemopreventive agent, the molecular mechanisms of selenium-mediated effects remain to be elucidated. Recent evidence suggests that selenium may mediate its chemopreventive effects by inducing apoptosis in human prostate cancer cells. Here we report that selenium-mediated apoptosis appears to involve membrane death receptor, DR5-dependent pathway in human prostate cancer cells. Selenium specifically upregulated DR5 expression but not that of DR4. Selenium upregulation of DR5 was coupled with caspase 8 activation and Bid cleavage thereby suggesting the existence of a potential cross-talk between the DR5 and the mitochondrial pathways. Thus, our results suggest that DR5 is specifically regulated by selenium and its activation may play an important role in selenium-mediated chemoprevention. 相似文献
985.
Sheikh SS Massloom HS 《ORL; journal for oto-rhino-laryngology and its related specialties》2002,64(6):448-450
Fat-containing lesions of endocrine organs are rare. Distinguishing lipoadenomas of the thyroid gland from lipoadenomas of parathyroid glands can be challenging during intraoperative consultation. Our patient had a well-circumscribed tan-pink nodule present on the surface of the thyroid gland, exhibiting abundant fat interspersed between the cells, with ample eosinophilic cytoplasm arranged in trabeculae and solid sheets. Immunohistochemistry showed strong positivity for thyroglobulin confirming the origin of the nodule to be thyroid. Only few cases of lipoadenomas of the thyroid and parathyroid have been reported in the literature. There is considerable histologic overlap between the two, making it difficult to determine the site of origin. We briefly discuss the features that may be helpful in this distinction. 相似文献
986.
987.
Adhesion interactions under flow have long been known to depend on applied wall shear stress. We investigated the ability of human na?ve neutrophils to adhere to xenogeneic endothelial cells under static and flow conditions. We demonstrate that human na?ve neutrophils bind to xenogeneic endothelial cells under flow conditions. This binding is dependent on the applied stress and is independent of Galalpha1,3-gal structures, ICAM-1, or its counter ligands LFA-1alpha and Mac-1. The binding was rapid and is characterized by stationary attachment with no obvious rolling or change in morphology. This binding leads to a transient increase in intracellular-free calcium levels in xenogeneic but not allogeneic-endothelial cells with occasional oscillations that persist long after the initial contact between the two cell types. Previous activation of xenoendothelium by autologous serum or human TNF-alpha augments binding of human na?ve neutrophils to the endothelial cells. Our data suggest novel interaction sites between the xenogeneic endothelial cells and human na?ve neutrophils. 相似文献
988.
989.
Symptom differences between older depressed primary care patients with and without history of trauma
Cook JM Areán PA Schnurr PP Sheikh JI 《International journal of psychiatry in medicine》2001,31(4):401-414
OBJECTIVE: The current study explored the relationship between past traumatic experiences and current depression in a sample of depressed older adult primary care patients. METHOD: Sixty-six patients were referred from primary care to a psychogeriatric clinic that specialized in the treatment of unipolar depressive disorders. All patients received an extensive psychological assessment. RESULTS: Twenty-one percent had a history of trauma reported in their medical charts. Despite no differences found on a clinician-rated measure of depression, those with a trauma history had more depressive symptoms on a self-report measure. CONCLUSIONS: Although older patients with a history of trauma may not appear more depressed than a non-trauma comparison group, they may be in more psychological distress. The clinical implications of these findings and recommendations for mental health professionals are discussed. 相似文献
990.
Siddiqi S Kielmann A Khan M Ali N Ghaffar A Sheikh U Mumtaz Z 《Health policy and planning》2001,16(2):193-198
In Pakistan, despite an elaborate network of over 5000 basic health units and rural health centres, supported by higher-level facilities, primary health care activities have not brought about expected improvements in health status, especially of rural population groups. A poorly functioning referral system may be partly to blame. System analysis of patient referral was conducted in a district of Punjab province (Attock) for the purpose of identifying major shortcomings, if any, in this domain. Respondents from 225 households were interviewed. Of the households experiencing serious illnesses less than half were taken to a nearest first-level care facility (FLCF). Major reasons included dissatisfaction with quality of care offered, non-availability of physician, and patients being too ill to be taken to the FLCF. The FLCF utilization rate was less than 0.6 patient visits/person/year. The mean number of patients referred per FLCF during the previous 3 months was 6.5 +/- 5.0. Only 15% of patients were referred on the prescribed referral form. None of the higher-level facilities provided feedback to FLCFS: Records of higher-level facilities revealed lack of information on either patient referrals or feedback. There were no surgical or emergency obstetric services available at any of the first-level referral facilities. Seventy-five percent of the patients attending the first-level referral facilities and 44% of the patients attending higher-level facilities had a problem of a primary nature that could well have been managed at the FLCF. As a result of the study findings, eight principal criteria were identified that need to be satisfied before a referral system may be considered functional. 相似文献