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In patients with septic shock, the cardiac index is often increased. Maldistribution of blood flow and regional hypoperfusion has been implicated as a key factor in the pathogenesis of organ dysfunction in these patients. We have investigated the relationship between cerebral blood flow and cardiac index in patients with septic shock. We used Doppler ultrasound techniques to investigate limb and carotid blood flow in 15 patients with septic shock and 9 nonseptic controls. In the nonseptic control patients, common femoral and brachial blood flow were proportional to cardiac index (r = 0.73 and 0.76; P = .038 and .017, respectively) reflecting a protective redistribution of flow to more vital organs. However, this relationship was absent in patients with septic shock (r = 0.23 and 0.21). Furthermore, in the septic patients but not the nonseptic controls, cerebral blood flow was correlated with the cardiac index (r = 0.66, P < .05 vs R = −0.36, NS in nonseptic controls). Carotid flow was independent of mean arterial pressure, Paco2 and Pao2 in patients with septic shock. These data are consistent with a loss of autoregulation of cerebral blood flow and a change in the control of limb blood flow in humans with septic shock.  相似文献   
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BACKGROUND: Carotid endarterectomy reduces the risk of stroke and death in patients with severe carotid artery stenosis. This study examined whether the technique used to close the arteriotomy influenced the rate of perioperative transient ischaemic attack (TIA), stroke or death. METHODS: A cohort of 236 patients undergoing carotid endarterectomy at a single centre was studied; 117 patients had primary closure of the arteriotomy and 119 patients in a sequential series had closure with a Dacron patch. A standard endarterectomy with completion intraoperative duplex imaging and digital subtraction angiography was used throughout. RESULTS: Patch closure was associated with a significant reduction in the 30-day combined death, stroke and TIA rate: 10.3 per cent for primary closure versus 2.5 per cent for patch closure (P = 0.017). The risk of any cerebral event (stroke or TIA) was also significantly reduced (7.7 versus 1.7 per cent; P = 0.033). Residual stenosis on completion angiography was more common after primary closure (24.6 versus 7.4 per cent; P = 0.003). CONCLUSION: Dacron patch closure had a higher technical success rate on completion imaging and was associated with a significant reduction in the risk of perioperative stroke, TIA and death.  相似文献   
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Plasmablastic lymphoma (PBL) is an aggressive high grade non-Hodgkin lymphoma which occurs predominantly in adult patients who are concomitantly afflicted with HIV infection. In contrast to several reports and studies of PBL in adult patients, PBL has very rarely been reported in pediatric patients. This article hereby provides collaborative clinicopathologic information of de novo PBL diagnosed in 3 pediatric patients with concomitant HIV infection. Cognizance of this rare tumor in the pediatric population coupled with antiretroviral therapy and prompt initiation of multimodality treatment may, in the future, facilitate improved outcome in pediatric patients with PBL.  相似文献   
36.
Many studies assessing the impact of national AIDS prevention programmes on knowledge, attitudes and practices have been published world-wide. Most have found that, while general knowledge increased, there was little change in behaviour. A survey of a random sample of 50 women attending a family planning clinic in Johannesburg determined the current knowledge, attitudes and practices of these sexually active women, aged 20-29 years. All selected respondents agreed to participate and a pretested structured questionnaire was completed. Most individuals had in excess of 7 years' schooling (78.0%), were single (58.0%) and domestic workers (28.6%). The majority were aware of AIDS (88.0%), but only 13.7% felt their knowledge was adequate. Fifty-two per cent knew sexual intercourse was a mode of transmission. Many misconceptions existed, 64.0% cited toilet seats, 47.1% sharing of utensils and 70.1% donating blood as routes by which HIV infection could be acquired. Only 47.1% and 34.1%, respectively, knew that the contraceptive pill and intra-uterine contraceptive device did not protect against HIV infection. Eighty-six per cent of the women were sexually active and 8.0% admitted to currently having more than one sexual partner. None used condoms and, generally, feelings regarding condom use were negative. Most (88.6%) believed AIDS patients should be hospitalised, 68.2% said in isolation wards, and 27.3% felt that AIDS patients should not be allowed to stay in the community. The implications of these findings are discussed and certain recommendations are made.  相似文献   
37.
Twenty-seven patients were examined who were undergoing cardiopulmonary bypass (CPB) surgery with either a bubble oxygenator or a capillary membrane oxygenator. The latter incorporated an arterial filter and bubble trap. A noninvasive Doppler ultrasound technique is described for monitoring irregularities in the Doppler flow signals attributable to gaseous microemboli detected in the middle cerebral artery during CPB. The ultrasound index for detecting gaseous microemboli (MEI) indicated the presence of such microemboli in 22 of the 27 patients during insertion of the aortic cannula. Measurements during CPB showed the MEI ranged from 4 to 39 in the 17 patients with a bubble oxygenator. However, all 10 patients with a membrane oxygenator had an MEI of 0. Varying the gas flow rates in 3 patients with bubble oxygenators showed a change in MEI from 4 +/- 4 (SD) at a flow rate of 2 L/min to 17 +/- 9 at a flow rate of 5 L/min. This observation supports the assumption that the MEI is providing quantitative information regarding the presence of gaseous emboli in the middle cerebral artery.  相似文献   
38.
Eighteen cases of focal epithelial hyperplasia (FEH) were investigated for the presence of human papillomavirus (HPV) group specific antigen by immunocytochemistry and HPV types 1, 6, 11, 13, 16, 18 and 32 by DNA in situ hybridization employing biotinylated probes. Seven (39%) specimens demonstrated the presence of HPV group specific antigen. Fifteen (83%) specimens were positive for HPV DNA: 9 (60%) showed HPV 32, of which 6 were on non-keratinized mucosa and 3 on border of keratinized and non-keratinized mucosa; 5 (33%) showed HPV 13, 4 lesions on keratinized mucosa and 1 on non-keratinized mucosa; 1 (7%) specimen on non-keratinized mucosa showed HPV-11 related. Two specimens on different sites from one patient showed the same HPV type and one patient had, in addition to FEH, a squamous papilloma also demonstrating the same HPV type. Results show a specific HPV distribution pattern in the epithelium indicating areas of high viral concentration adjacent to areas of low or no viral concentration. This study also indicates the possibility of tissue-site specificity or a latent infection and the possibility of a yet unidentified HPV type associated with FEH. It is suggested that future monitoring of patients be carried out with special reference to HPV type and anatomical distribution pattern for FEH lesions.  相似文献   
39.
One hundred and forty oral squamous cell papillomas (SCPs) were subjected to immunocytochemical staining for papillomavirus antigen using the immunoperoxidase-PAP method 41% of the oral squamous papillomas showed positive intranuclear staining, 50% were negative and the remaining 9% showed both intranuclear and cytoplasmic staining. In view of these findings it is suggested that a review of the etiology of lesions diagnosed as oral SCPs should be considered.  相似文献   
40.
Limited epidemiological data on acquired immunodeficiency syndrome (AIDS) and human immunodeficiency virus (HIV) infection have been assembled by voluntarily reported AIDS figures, blood donor serum prevalence and high-risk sentinel population and random background population sero-prevalence studies. The HIV epidemic in South Africa can thus be shown to consist of four separate epidemics of which the heterosexual epidemic will undoubtedly constitute the major growth in this country. Intervention must be directed to shrinking the promiscuous core which sustains this epidemic by directing attention at female prostitution and limiting the reproductive rate of the epidemic by energetic and professionally directed education at an early stage of a child's school career. Sexually transmitted diseases will play a major role in the determination of the extent of the heterosexual epidemic.  相似文献   
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