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61.
Because the potential urban yellow fever (YF) mosquito vectors Aedes aegypti and Ae. albopictus are at historical highs in Brazil, both in terms of density and geographical range, we assessed the risk of an urban YF epidemic in Brazil. We evaluated and confirmed in a laboratory setting the vector competence of Brazilian Ae. aegypti for a currently circulating strain of YF virus, and investigated the potential for Brazilian Ae. albopictus to transmit YF.  相似文献   
62.
We report an unusual case of aggressive ALK-positive anaplastic large cell lymphoma with widespread mediastinal involvement immediately preceded by an acute Epstein-Barr virus (EBV) infection. Following initiation of chemotherapy and radiological evidence of significant tumor regression, the patient suffered a fatal massive upper gastrointestinal hemorrhage from an aorto-esophageal fistula. The relevant literature relating to EBV in the pathogenesis of ALK-lymphomas and literature relating to aorto-enteric fistula (AEF) in mediastinal lymphoma is reviewed.  相似文献   
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64.
BACKGROUND: Millions of dollars are spent annually on the production and distribution of patient education materials; however, there are no studies describing their actual use by physicians. Using qualitative data from a large comparative case study, our analysis evaluates how patient education materials are organized and used in family practices. METHODS: Eighteen purposefully selected family medicine practices were directly observed for 4 to 12 weeks each. A total of 57 providers were shadowed by a research nurse, and detailed field notes on 1600 patient encounters were recorded. A 3-member analysis team reviewed the qualitative data and identified emergent patterns. RESULTS: Clinics' use of patient education materials fell mostly into 2 distinct patterns. "Stockpilers" were providers who relied on the clinic staff to develop and organize a common library of patient education handouts. Providers with a "personal stash" collected much smaller numbers of materials that they personally maintained. Providers in the latter group had a known repertoire of a limited amount of educational material and used it more often than providers with access to a greater variety and number of handouts. In all practices, providers distributed most handouts; staff and self-selection by patients played a minor role. CONCLUSIONS: It appears that provider involvement and familiarity with patient education materials are key to their use in clinical practice. Clinicians use written patient education materials most efficiently by personally selecting and maintaining a small number of handouts that address topics most relevant to their practice.  相似文献   
65.
It has been commonly believed that children in developing countries pass stools that are very different from those of developed countries. A community based study on defecation frequency, stool weight, and consistency was conducted in a cohort of 300 Myanmar (Burmese) children aged 1 to 4 years. Most (80.3%) children opened their bowels daily and none passed more than three stools a day. The mean (SD) defecation frequency was 6.98 (1.94) times a week and total stool weight was 596 (221) g a week. The majority (61%) of children passed soft stools. At all ages, there was no significant difference in the defecation frequency, stool weight, and consistency between boys and girls, those on adult style diet and those partially weaned, and between age groups.  相似文献   
66.
The preoptic anterior hypothalamus (POAH) of rats housed at three ambient temperatures was implanted with perfusion apparatuses. Response of heat production to displacement of POAH temperature was determined for control animals and animals with burns (31% +/- 3% total body surface area). At an ambient temperature of 22 degrees C there was a significant increase in thermosensitivity of the POAH for both control rats and rats with burns compared with thermosensitivity at 32 degrees C. Within ambient temperatures there was no effect on thermosensitivity detected for rats with burns compared with control rats. The threshold temperature for heat production was shifted significantly upward (p less than 0.05) both by a lower ambient temperature and by burn injury. The reference temperature for heat production was also shifted to the right by burn injury (p less than 0.05). The significant shifts to the right for threshold temperature and reference temperature for heat production enhance the organisms's ability to meet the stress of the hypermetabolic response. At a warm ambient temperature (32 degrees C) there are no significant differences in thermoregulation detected in animals with burns or control animals.  相似文献   
67.
BACKGROUND: Chronic exit-site and tunnel infections of the peritoneal dialysis catheter are significant causes of catheter loss. Surgical salvage procedures that can effectively resolve the infection and preserve dialysis are of major importance. METHODS: Thirteen patients with chronic exit-site and tunnel infections underwent surgical salvage consisting of unroofing the tunnel tract and shaving of the superficial catheter cuff. A control group of 138 patients implanted during the same time span as the study group was used for infection rate and survival comparisons. RESULTS: The salvage procedure cured the infection in all patients. No dialysate leaks occurred. Peritoneal dialysis was not interrupted. Surgical salvage provided successful long-term peritoneal dialysis that was equivalent to the cohort dialysis population. CONCLUSION: Surgical salvage by unroofing/cuff shaving is an effective long-term solution for chronic exit-site and tunnel infection.  相似文献   
68.
Psychiatric problems in the first year after mastectomy   总被引:8,自引:0,他引:8  
The psychiatric morbidity associated with mastectomy was assessed in 75 women by following them up from the time they presented with suspected breast cancer to one year after the operation. Fifty women with benign breast disease served as controls. Throughout the follow-up period the incidence of psychiatric problems was higher among the women who had undergone mastectomy. One year after surgery 19 (25%) of these women compared with only 5 (10%) of the controls needed treatment for anxiety or depression or both, and 16 (33%) compared with 3 (8%) respectively had moderate or severe sexual difficulties. Altogether 29 patients in the mastectomy group (39%) and six of the controls (12%) had serious anxiety, depression, or sexual difficulties. Of the eight women in the mastectomy group who sought help for their problems, only two felt that the help given had been appropriate. The inability to recognise and treat these emotional disturbances is a common and serious problem. Monitoring by specially trained nurses and social workers might help to identify them earlier and even reduce them.  相似文献   
69.
An anthropometric analysis of 200 adult patients was performed to provide better guidance in catheter selection and placement. Height, weight, various abdominal wall measurements, and gender effects were analyzed. Suitability of Tenckhoff catheters with straight and preformed bends in the intercuff segment was evaluated regarding ability to produce deep pelvic position of the catheter tip and ideal exit site location. Conflicts with belt line and with skin creases and folds were recorded. Results showed that abdominal wall measurements varied widely by height and weight. Swan neck catheters with a downwardly directed external limb and exit site were significantly better suited for females (62% versus 27%, p < 0.0001). Tenckhoff catheters with straight intercuff segments with a laterally directed tunnel tract and exit site were significantly better matched to males (78% versus 30%, p < 0.0001). Neither catheter was suitable in 25% of subjects, emphasizing the need for an extended catheter system capable of remotely locating the exit site to the upper abdomen or chest without compromising pelvic position of the catheter tip. Appropriate preoperative evaluation with selection of the best suited catheter should replace the substandard practice of using a pet catheter to fit all patients and rigidly placing the insertion incision at a set location irrespective of body habitus.  相似文献   
70.
INTRODUCTION: Elevated hearing thresholds have been documented in some astronauts after long-term spaceflights although noise levels were lower than those normally associated with noise-induced hearing loss in ground-based operations. The present study was conducted to determine whether prolonged exposure (70 h) to levels (72 dBA) recorded on the International Space Station (ISS) service module would impact diverse measures of auditory function, as well as cognition and memory, motivation, and cardiovascular function. METHOD: Five mixed gender subgroups of five normal-hearing subjects, aged 20-50 yr, were sequestered for 70 h in an environment that modeled conditions on the ISS. They were assigned to one of three background conditions: quiet (n = 5), continuous noise from the ISS service module (n = 10), or continuous noise during the day only (n = 10). Subjects were tested repeatedly within and across days as individuals or pair mates. RESULTS: There were no negative effects of the noise on any of the outcome measures. Introduction of a delay or noise in a communication channel used in the assessment of speech communicability significantly affected the time taken for joint problem solving by partners. DISCUSSION: The results of this study were not consistent with the observation of hearing loss measured after spaceflights. Nor were changes evident in cognition, motivation, or cardiovascular function. Factors which might account for the discrepancy are discussed.  相似文献   
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