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991.
In a retrospective review, 62 patients treated for rectal cancer by contact (endocavitary) irradiation at The Cleveland Clinic Foundation were analyzed. This treatment modality delivers high dose, low penetration irradiation to a rectal cancer by direct contact of a 50 KV x-ray source through a special proctoscope. Cancers selected for this treatment include small (3 cm or less), mobile tumors without presacral lymphadenopathy that are within reach of digital examination and are well- or moderately well-differentiated adenocarcinomas. Between 1973 and 1984, 62 patients (37 males, 25 females) were treated—46 by contact irradiation alone and 16 by contact irradiation after excisional biopsy. The median tumor dose was 12,000 rads administered in four fractions at monthly intervals. Mean follow-up was 31 months. Fiftysix patients (90 percent) were disease-free at the time of review or death (ten died from unrelated causes). Eleven patients (18 percent) developed local recurrence but eight of these without distant metastases were rendered disease-free by other treatment—six by surgical resection and two by further radiotherapy. Mean time since secondary treatment is 20 months. Three patients are alive with incurable disease and three have died from cancer—in three of these six patients there was no evidence of local disease. Ulcerated tumors developed local recurrence in five of 17 cases (29 percent) while polypoid tumors recurred locally in six cases (14 percent). Morbidity from the treatment was minor in nature. It is suggested that contact (endocavitary) irradiation is effective treatment for carefully selected cases of rectal cancer Read at the meeting of the American Society of Colon and Rectal Surgeons, Washington, D.C., April 5 to 10, 1987.  相似文献   
992.
Significant progress has been made in recent years in unraveling the dynamic mechanisms involved in the production of unstable angina. This knowledge, and advances in medical and interventional therapy allow the formulation of treatment strategies aimed at specific pathogenic mechanisms and promise to reduce mortality and morbidity. This review covers the diagnosis, pathogenesis, risk stratification, and therapy of unstable angina.  相似文献   
993.
Use of pacing in sick sinus syndrome and recent developments in pacemaker therapy for intermittent atrial fibrillation raise the question of whether external electrical cardioversion should be used for termination of atrial fibrillation. This paper analyzes three cases of pacemaker and/or electrode dysfunction appearing after direct current (DC) cardioversion for termination of atrial fibrillation. Despite similar conditions during cardioversion in all cases, different dysfunctions reflecting damage to the pulse generator and/or a rise of the stimulation threshold in both, atrial and ventricular leads, have been observed. The possible mechanisms for these effects are discussed and recommendations for the management of cardioversion in patients with permanent pacemaker systems are given.  相似文献   
994.
Heat-stable opsonins from sera of cystic fibrosis (CF) patients were investigated for their ability to activate complement. Complement activation by Pseudomonas aeruginosa after opsonization with patient serum was examined in a complement-consumption assay. Absorption of patients' sera with formalin-treated and boiled bacteria removed specific antibodies and the complement activation decreased. We found a positive correlation between serum complement-activation ability and IgG3 antibody levels to lipopolysaccharide (LPS), alginate, and a crude mixture of P. aeruginosa antigens (sonicate) in a group of patients with high levels of anti-Pseudomonas precipitins. In the same group of patients a significant negative correlation was found between complement activation and lung function. Eighteen patients have been followed longitudinally with serum samples covering the pre-infection, the early, and the late stages of chronic infection. Patients with poor lung function showed significantly higher levels of complement-activation capacity. We conclude that patients with high levels of specific IgG3 antibodies are able to induce a high level of complement activation and then develop more aggressive pulmonary tissue damage, probably secondary to local immune complex formation. Pediatr Pulmonol. 1995; 20:71–77 . © 1995 Wiley-Liss, Inc.  相似文献   
995.
The arrhythmia generating dysplasia of the right ventricle is a congenital anomaly suggesting a hereditary substratum. It usually manifests itself as follows: a young patient, with recurrent episodes of ventricular tachycardiac. There is no "pathognomonic sign" of dysplasia. The latter may only be determined by anatomical examination of the heart, macroscopically as well as microscopically. The most difficult differential diagnosis concerns minor or localized forms of dilated idiopathic myocardiopathy or sequelae of myocarditis with ventricular tachycardia originating in the right ventricle. It seems, currently, more appropriate to talk about "arrhythmia generating syndrome of the right ventricle" rather than arrhythmia generating dysplasia of the right ventricle, in these particular cases. The arrhythmia generating syndrome of the right ventricle could cause a sudden death in these young patients, especially during a violent physical exercise or practise of sports. The current nosological classification is based on an experience acquired by comparing a few isolated cases. The search for late potentials by summation-mean measurements and nuclear magnetic resonance could provide a new diagnostic approach.  相似文献   
996.
BACKGROUND: We previously demonstrated that short-cycle structured intermittent therapy (SIT; 7 days without therapy followed by 7 days with antiretroviral therapy [ART]) with a ritonavir-boosted, indinavir-based, twice-daily regimen maintained suppression of plasma HIV viremia while reducing serum levels of lipids. Adherence to such a regimen may be problematic for certain patients. METHODS: Eight patients with a history of receiving combination ART that maintained suppression of plasma HIV RNA to <50 copies/mL received a once-daily SIT regimen of didanosine, lamivudine, and efavirenz. RESULTS: For 7 patients, suppression of plasma HIV RNA to <50 copies/mL was maintained for 60-84 weeks. Four patients with adequate samples had no evidence for an increase in plasma viremia for up to 72 weeks, by use of an assay with a limit of detection of <1 copy/mL. The lack of rebound viremia may be the result of the persistence of efavirenz in plasma on day 7 of the no-therapy period, as was detected in 7 of 7 patients. There was no significant change in CD4(+) T cell counts or serum hepatic transaminase or lipid levels. CONCLUSION: A once-daily short-cycle SIT regimen maintained suppression of plasma HIV RNA while preserving CD4(+) T cell counts. Such a regimen may have importance in resource-limited settings where the monetary cost of continuous ART is prohibitive.  相似文献   
997.
We studied the dynamics of CD4 cell counts after the interruption of virologically successful highly active antiretroviral therapy (HAART) in 139 patients. Changes in CD4 cell counts during HAART interruption followed a biphasic pattern: an initial rapid decline during the first month followed by a slow decrease. During 48 weeks of follow-up mean CD4 cell counts remained just above the mean pre-HAART level. This limits the feasibility of structured treatment interruptions for patients with low nadir CD4 cell counts.  相似文献   
998.
A 47 year old patient underwent endocavitary electrophysiological investigation for recurrent syncopal episodes occuring three years after an inaugural enterior myocardial infarction. Syncopal ventricular tachycardia was induced during the investigation when the bipolar catheter was in contact with the Bundle of His and several external electric shocks were required for its reduction. During cardioversion a complete intra-hisian atrio venticular block was observed and remained permanently although the values of the conduction intervals had previously been normal. This complication of defibrillation is thought to be the result of an induction phenomenon.  相似文献   
999.
Corrected QT intervals were determined in 13 patients with severe, chronic hypercalcemia. The QOTC interval was short in only 2 of 14 instances; QATC in 5 of 15 instances, and QETC in 5 of 16 instances. The correlations between serum calcium and the QTC measurement were not significant when evaluating either linear or curvilinear (quadratic) relationships. Small and inconsistent changes were found when comparing the QT intervals before the development of the hypercalcemic episode, during hypercalcemia, or after successful treatment. We conclude that shortening of the QT interval is an unreliable index of clinical (chronic) hypercalcemia.  相似文献   
1000.
INTRODUCTION AND OBJECTIVES: This cross-sectional study examined the overall clinical characteristics and management of 1252 outpatients with heart failure in 3 countries (Spain, France and Germany). MATERIAL AND METHOD: A standardized questionnaire was used to record demographic, diagnostic, clinical and treatment data for all patients seen on one day (26 April 2001) by 465 outpatient cardiologists. RESULTS: Men accounted for 62.1% of the patients in the population, and mean age of the patients was 68.3 years. In the twelve months prior to the study 78% of the patients consulted their physician at least once because of heart failure, and 36.2% had hospital admissions. Differences between the three countries were observed in reported causes of heart failure (alone or in combination) such as ischemic heart disease (France 40.7%, Germany 41.3%, Spain 26%, P<.0001) and hypertension (France 10.7%, Germany 16.7%, Spain 43.6%, P<.0001). How-ever the proportion of patients with prior myocardial infarction was very similar (France 63.7%, Germany 69.5%, Spain 65%, P=NS). Diuretics were not prescribed in 19.7% of the patients, ACE inhibitors were not prescribed in 27.9%, and beta blockers were not prescribed in 52.3%. CONCLUSIONS: The study provides further information on the consumption of large amounts of medical resources because of heart failure. The reported etiologies differed between countries. However, the proportion of patients with prior myocardial infarction was very similar. Treatment with ACE inhibitors and beta blockers was slightly more common than previously reported, although beta blockers continue to be underused.  相似文献   
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