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BACKGROUND AND OBJECTIVE: Postoperative nausea and vomiting (PONV) is a frequent and unpleasant experience that may increase postoperative complications and costs. For surgical procedures with a high risk of PONV, prevention is preferable to treatment. In this study, the authors explore the dose-response relationship between granisetron administered just prior to the end of surgery and post-operative nausea and vomiting in patients undergoing abdominal hysterectomy. METHODS: This was a randomized, double-blind, placebo-controlled, pilot study of post-operative nausea and vomiting prevention. Patients undergoing elective open abdominal hysterectomy requiring general anaesthesia received a single dose of granisetron 0.1, 0.2 or 0.3 mg or placebo administered approximately 15 min prior to the end of surgery. The primary efficacy end-point was the proportion of patients with no vomiting in the 0--6 h interval following medication administration. No inferential statistics were planned. RESULTS: The proportion of patients with no vomiting episode in the 0--6 h interval after administration of study medication was higher in each granisetron treatment group (>90%) than in the placebo group (77%). Proportions of patients with no vomiting episodes in the 0--24 h interval were similar across treatment groups. Results of analyses of proportions of patients with no moderate or severe nausea episodes, proportions of those requiring rescue medication and times to first use of rescue medication suggested a treatment effect of granisetron relative to placebo in both the 0--6 and 0--24 h intervals. Similar proportions of patients in each treatment group reported at least one adverse event. CONCLUSIONS: Granisetron at doses of 0.1, 0.2 and 0.3 mg administered just prior to the end of surgery suggested a trend of improved efficacy compared to placebo in preventing postoperative nausea and vomiting in the first 6 h after abdominal hysterectomy. This pilot study did not identify a dose-response relationship.  相似文献   
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HYPOTHESIS: We hypothesized that aerosol distribution in the lungs of patients with cystic fibrosis changes with positive expiratory pressure (PEP). METHODS: Eight patients were randomized to one of 2 conditions. On one study day, patients inhaled saline aerosol containing 99mtechnetium generated by a Pari LC Plus nebulizer and exhaled through a Pari PEP device. On another day, the same patients exhaled through a low-resistance Pari filter (no PEP). Afterwards, they underwent gamma-camera lung imaging. Images were analyzed for lung deposition fraction, expressed as a percent of the initial nebulizer activity, and deposition pattern, expressed in terms of inner-outer and apical-basal ratios. RESULTS: Lung deposition fraction was significantly lower with the Pari PEP device; the mean + SD deposition fraction was 6.10 + 3.05% (median 6.20%) with PEP, compared to 10.76 + 4.52% (median 10.32%) (p = 0.0078) without PEP. The inner-outer ratio was 2.01 + 0.69 (median 2.23) with PEP, which was significantly lower than without PEP (2.76 + 1.33, median 2.55) (p = 0.004). The apical-basal ratio was 0.82 + 0.31 (median 0.80) with PEP, which was not significantly different from no PEP (1.00 + 0.49, median 0.90). CONCLUSION: These results indicate that less aerosol is deposited in the lungs of patients with cystic fibrosis when the Pari LC Plus nebulizer is used with the Pari PEP device, as described in these experiments. Nevertheless, aerosol administration with this nebulizer and PEP device also results in a proportional redistribution of aerosol to the peripheral airways, compared to nebulization without the PEP device. The clinical relevance of this subtle redistribution of aerosol in cystic fibrosis patients will probably depend on the drug administered and disease severity.  相似文献   
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It is becoming clear that cells do not only respond to micrometric scale topography, but may also respond to topography at the nanometric scale. Nano-fabrication methods such as electron beam lithography are, however, expensive and time consuming. Polymer demixing of poly(styrene) and poly(4-bromostyrene) has been found to produce nano-scale islands of reproducible height, and the islands have been previously shown to effect cell events such as adhesion, spreading, proliferation, and differentiation. This study uses demixed poly(styrene) and poly(n-butyl methacrylate) to produce nano-islands with closer packing and narrower widths compared with those previously studied. Observations have been made of morphological and cytoskeletal changes in human fibroblasts interacting with 10- and 50-nm-high islands. The methods used included scanning electron microscopy, fluorescent microscopy, and optical microscopy. The results indicated that the cells do not respond differently to the 10-nm islands compared with planar samples but, in contrast, the 50-nm islands are nonadhesive.  相似文献   
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Between 1978 and 1981, 85 patients with advanced squamous cell carcinoma of the head and neck were randomized to receive induction VBM followed by radiotherapy, or radiotherapy alone. The shortest follow-up is thus 6 years. The median survival of patients receiving induction chemotherapy was 46 weeks, that of the radiotherapy group alone was 75 weeks. As the two groups were not balanced despite randomization, multivariate methods (GLIM) were used to identify significant prognostic factors. These were: response to radiotherapy (P less than 0.001), nodal status (P less than 0.001), age (P less than 0.01), and histological grade (P less than 0.01). Neither treatment with, nor response to, chemotherapy had a significant effect on survival.  相似文献   
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Meyerovitz  MF; Reagan  K; Friedman  PL 《Radiology》1989,171(3):866-868
Posteroanterior (PA) and caudally angulated PA views were obtained in 20 patients undergoing routine coronary arteriography. Although the left main coronary artery (LMCA) was seen well on both views in all patients, the PA-caudal view improved depiction of the LMCA bifurcation in 15 (75%). In addition, the PA-caudal view markedly improved depiction of the circumflex artery, affording optimal depiction of this artery and its branches in 78%-89% of patients. Neither the PA nor the PA-caudal view allowed adequate depiction of the left anterior descending artery. Thus, the PA-caudal view should supplant the PA view in routine coronary arteriography.  相似文献   
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Recurrence after radiotherapy for glottic carcinoma   总被引:2,自引:0,他引:2  
L Viani  P M Stell  J E Dalby 《Cancer》1991,67(3):577-584
A series of 478 patients with T1-3N0 glottic carcinoma treated by irradiation is presented. Of these patients, 320 were previously untreated, whereas 158 patients were referred for treatment of a recurrence after receiving radiotherapy elsewhere. The primary recurrence rate in the previously untreated patients was 10%. The rate was higher in T2 and T3 tumors, poorly differentiated tumors, and in patients who were in poor general condition. Over 80% of the recurrent tumors were Stage pT3 or pT4, whereas 12% of total laryngectomy specimens showed necrosis only with no evidence of tumor. The necrosis rate in previously untreated patients was 1% for T1 tumors, 4% for T2 tumors, and 3% for T3 tumors. Of all tumors, 60% were transglottic when they recurred, whereas only 29% were confined to the glottis at recurrence. Histologic diagnosis had a high sensitivity but a low specificity, indicating that a negative histologic report is unreliable. Of patients with a recurrent primary tumor, 13% were untreatable. The 5-year survival after a primary recurrence was 39%, and the main prognostic factors were sex, T stage at recurrence, and time to recurrence. Of patients available for follow-up at 5 years 49% were alive with a larynx, 5% were alive without a larynx, 13% were dead of the original cancer, and 33% had died of other causes. In those suffering a primary recurrence, the commonest cause of death was a subsequent lymph node metastasis, followed in order of frequency by stomal recurrence and recurrence in the pharyngeal remnant. The hospital mortality rate after laryngectomy was 3%, and 30% of patients undergoing laryngectomy developed a pharyngocutaneous fistula. The recurrence rate in lymph nodes was 14% at 5 years, general condition and T stage being the only significant predictors of recurrence. Only 17% of patients had small (N1) nodes by the time the diagnosis of cervical lymph node recurrence was made, and 27% of all patients were unsuitable for treatment. Host, tumor factors, and time to recurrence were not significant predictors of survival after node recurrence. The survival rate 5 years after node recurrence was 16%, and the main cause of death in those who died was uncontrolled disease in the neck. The hospital mortality after salvage neck dissection was 4.7%.  相似文献   
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