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51.
The effect of intravenous streptokinase therapy on the time course of functional recovery was investigated in a controlled study of 64 patients randomized within 3 hours after the onset of acute myocardial infarction (AMI). Contrast ventriculography was performed 1 to 4 days after AMI and repeated 5 weeks later. Wall motion was analyzed by the centerline method in the central infarct, peripheral infarct and noninfarct regions. In patients with ventriculographic data at the early catheterization, streptokinase-treated patients had less severe hypokinesia in the central infarct region than control patients (-2.9 +/- 0.9 [n = 29] vs -3.4 +/- 0.7 standard deviations below normal [n = 21], p less than 0.05). The benefit of streptokinase was more marked in the peripheral infarct region (-1.5 +/- 0.7 vs -2.1 +/- 0.6, p less than 0.001). As a result, the ejection fraction was slightly higher in treated versus control groups (46 +/- 10 vs 43 +/- 7%, respectively; difference not significant). At 5 weeks, function in the streptokinase and control groups had diverged further because of continued improvement in the streptokinase-treated patients. This study shows that streptokinase benefits left ventricular (LV) function by 1 to 4 days after AMI, earlier than previously reported. The benefit was not limited to the peripheral infarct region, where ischemia might have been less severe, but was also seen in the central infarct region. The implication is that thrombolytic therapy can improve LV function during the period of myocardial stunning, while myocardial function is still recovering.  相似文献   
52.
GOALS: To give an overview on the theoretical and practical applications of chemosensory event-related potentials. METHODS: Chemosensory event-related potentials (ERPs) may be elicited by brief and precisely defined odorous stimuli. Based on the principles of air-dilution olfactometry, a stimulator was developed in the late 1970s, which allows stimulation of the olfactory neuroepithelium and the nasal mucosa with no concomitant mechanical stimulation. Chemosensory ERPs were obtained after stimulation of the olfactory nerve (olfactory ERPs) or the trigeminal nerve (somatosensory or trigeminal ERPs). The characteristics of the stimulator for chemosensory research as well as the variables influencing the responses are discussed in this paper. RESULTS: Implementation and normative data from our department are reported with different clinical examples from otorhinolaryngologic clinic. The bulk of the evoked response consists of a large negative component (often referred to as N1), which occurs between 320 and 450 ms after stimulus onset. This component is followed by a large positive component, often referred to as P2, occurring between 530 and 800 ms after stimulus onset. Absence of olfactory ERPs and presence (even with subtle changes) of somatosensory ERPs is a strong indicator of the presence of an olfactory dysfunction. CONCLUSIONS: This review examines and discusses the methods of chemosensory stimulation as well as the electrophysiological correlates elicited by such stimuli. The clinical applications of chemosensory ERPs in neurology and otorhinolaryngology are outlined.  相似文献   
53.
Immunotherapy requiring an efficient T lymphocyte response is initiated by antigen delivery to antigen-presenting cells. Several studies have assessed the efficiency of various antigen loading procedures, including microbial vectors. Here a live strain of Pseudomonas aeruginosa was engineered to translocate a recombinant antigenic protein into mammalian cells via the type III secretion system, a bacterial device translocating effector proteins into host cells. Optimization of the vector included virulence attenuation and determination of the N-terminal sequence allowing translocation of fused antigens into cells. In vitro delivery of an ovalbumin fragment by the bacterial vector into dendritic cells induced the activation of ovalbumin-specific CD8(+) T lymphocytes. Mice injected with the ovalbumin-delivering vector developed ovalbumin-specific CD8(+) T lymphocytes and were resistant to a subsequent challenge with an ovalbumin-expressing melanoma. Moreover, in a curative assay, injection of the vaccine vector 5 and 12 days after tumor implantation led to a complete cure in five of six animals. These results highlight the utility of type III secretion system-based vectors for anti-tumor immunotherapy.  相似文献   
54.
55.
Background: Percutaneous coronary intervention (PCI) is performed in patients with coronary artery disease who are undergoing major noncardiac procedures to reduce perioperative cardiac morbidity and mortality. However, the impact of this approach on postoperative outcome remains controversial.

Methods: The authors analyzed a cohort of 1,152 patients after abdominal aortic surgery in which 78 patients underwent PCI. A propensity score analysis was performed. Also, using a logistic regression model, the authors determined variables associated with a severe postoperative coronary event or a death in patients without PCI. Then, in patients with PCI, they compared the expected and observed outcome.

Results: Five variables (age > 75 yr, blood transfusion > 3 units, repeated surgery, preoperative hemodialysis, and previous cardiac failure) independently predicted (with 94% correctly classified) a severe postoperative coronary event, and five variables (age > 75 yr, repeated surgery, previously abnormal ST segment/T waves, previous hypertension, and previous cardiac failure) independently predicted (with 97% correctly classified) postoperative death. In the PCI group, the observed percentages of patients with a severe postoperative coronary event (9.0% [95% confidence interval, 4.4-17.4]) or death (5.1% [95% confidence interval, 2.0-12.5]) were not significantly different from the expected percentages (8.2 and 6.9%, respectively). When all patients were pooled together, the odds ratios of PCI were not significant. The propensity score analysis provided a similar conclusion.  相似文献   

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57.
This study analysed the possibilities of returning to work of professional drivers after a cardiac event and rehabilitation. The population comprised 94 consecutive patients, all men, average age 48.8 years (range 30 to 63 years) referred after coronary bypass surgery (N = 39), myocardial infarction (N = 38), angina (N = 4) or valve replacement surgery (N = 13). Advice on professional reinsertion was given after the rehabilitation program, authorization to drive being given in the absence of cardiac symptoms, residual myocardial ischaemia, severe left ventricular dysfunction and serious ventricular arrhythmias. After 35 months, 4 patients were lost to follow-up; of the 90 remaining patients, the frequency of return to work (maximal at the 9th month) was 65.6% with 84.7% obtaining a renewal of their driving licence. In this series, 81% of patients were asymptomatic, 2 died, 16.7% had further cardiovascular complications. The morbidity and mortality were significantly greater in the group who had to stop driving (N = 40) (32.5% vs 8%, p < 0.001). Non complications occurred during work in those who resumed driving. This study confirms the safety of allowing low risk professional drivers, identified during cardiac rehabilitation by simple, reliable clinical and paraclinical criteria, to return to work.  相似文献   
58.
Background: Many patients treated for breast cancer with radiotherapy will survive their disease and be at risk for treatment-related sarcoma for many years. Methods: In order to identify patients with post-treatment sarcoma and define this disease, we examined the records of 99 patients treated for sarcoma with a history of antecedent breast carcinoma. Of these patients, 51 were felt to have a sarcoma unrelated to breast cancer treatment and 48 were felt to have a treatment-related sarcoma (secondary to lymphedema and/or radiation). Results: Lymphangiosarcoma of the extremity was the most common histologic subtype of post-treatment sarcoma, accounting for 22 of 48 cases (46%). Twenty-six patients (54%) developed nonlymphangiosarcoma post-treatment sarcoma; all of these were radiation-associated sarcomas. The median latency interval between the diagnosis of breast cancer and the development of sarcoma was 11 years (range 4–44) and was not different between the two groups. However, patients with nonlymphangiosarcoma were significantly younger when diagnosed with breast cancer than were those with lymphangiosarcoma of the extremity (median 43 vs. 51 years, p<0.001). The survival of all 48 patients was poor: 5-year survival was 29%. Five-year survival of patients with other types of post-treatment sarcoma was just as poor as those with lymphangiosarcoma of the extremity (30% vs. 28%, p=0.98). Conclusions: Patients who develop sarcoma after treatment for breast cancer have a poor prognosis whether it occurs as Stewart-Treves syndrome or other types of post-treatment sarcoma. Younger patients may be at higher risk than are older patients for the development of nonlymphangiosarcoma post-treatment sarcoma.Presented at the 46th Annual Cancer Symposium of the Society of Surgical Oncology, Los Angeles, March 18–21, 1993.  相似文献   
59.
The increasing prevalence of adolescent obesity justifies widespread effort and attention of the paediatrician. In order to manage, following points are to be documented: (I) weight status assessed on the basis of body mass index (BMI)split in two levels: obesity grade I: >or=97 ème centile, obesity grade 2: level IOTFC 30; (2) complete anamnesis including age at adiposity rebound and existence of overweight in family; (3) research of associated morbidity and medical risks;(4) assessment of food intake and feeding practice; (5) assessment of physical activity; (6) talk with the adolescent to assess the psychological status, looking after depressive symptoms, anxiety, loss of self esteem. Once the items are documented, it allowed making a plan to manage the obesity in alliance with the adolescent and his family.  相似文献   
60.
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