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991.
DTI-015 (BCNU in 100% ethanol) utilizes solvent-facilitated perfusion for the intratumoral treatment of gliomas. The water-miscible organic solvent vehicle, ethanol, facilitates a rapid and thorough saturation of the'tumor with the dissolved anticancer agent, BCNU. Rats bearing established intracranial T9 gliosarcoma tumors received no treatment (group 1), a single intratumoral injection of ethanol vehicle (group 2) or DTI-015 (5 mg/kg BCNU) (group 3), or a single intratumoral injection of DTI-015 followed by systemic BCNU (group 4). Ethanol alone (n=13) had no effect on survival; MST=17 days compared to 18 days for untreated controls (n=35). DTI-015 (n=45) produced an ILS of 417% (MST=93) and 472% (MST=103) when combined with systemic BCNU (n=14). Overall, 24 of 59 rats receiving DTI-015 were judged to be cured, with 20 living a normal life span of 600 to 700 days, and 4 rats sacrificed healthy at 121, 135, 307, and 384 days post DTI-015 with no evidence of viable T9 tumor. Histology demonstrated that DTI-015 totally eradicated the T9 tumors in animals living a normal life span. The results demonstrate that a single injection of DTI-015 produces a 40% cure rate in rats bearing established intracranial T9 tumors.  相似文献   
992.
El leiomiosarcoma de la vena cava es un tumor vascular maligno de presentación rara que tiene mal pronóstico. Habitualmente se presenta en mujeres entre la quinta y sexta décadas de la vida. Es una lesión de bajo grado de malignidad pero habitualmente fatal. En este artículo se revisan dos casos clínicos de leiomiosarcomas de la vena cava inferior de localización pararrenal. Ambos ocurrieron en mujeres y la resección radical fue la forma de manejo. En un paciente se utilizó pericardio bovino y en el otro un injerto de politetra-fluoroetileno como reemplazo de la vena cava. Ambos pacientes presentaron recurrencias locales y sistémicas. Una falleció 5 a?os después del diagnóstico con recurrencia local y sistémica, la otra se encuentra viva pero con recurrencia local y hepática.  相似文献   
993.
BACKGROUND: Intravesical instillations with bacillus Calmette-Guérin (BCG) is considered the treatment of choice in the prophylaxis of high-grade superficial bladder carcinoma and in the treatment of carcinoma in situ (CIS) of the bladder. METHODS: There is no previous experience with BCG treatment in patients with renal transplantation. Theoretically, immunosuppression is a contraindication because of the risk of severe morbidity and sepsis. We present our experience with endovesical BCG in three renal transplant patients, under immunosuppressive treatment, with high-grade superficial bladder cancer and CIS. RESULTS: Two patients are free of disease at 17 and 60 months. One patient developed disease recurrence and underwent a radical cystectomy. There was neither change in renal function nor any clinical evidence of tuberculous infection. CONCLUSIONS: Intravesical BCG in superficial bladder cancer and/or CIS is a valid option, with no added morbidity to renal transplant patients.  相似文献   
994.
995.
OBJECTIVE: Voluntary HIV counseling and testing are provided to all Brazilian pregnant women with the purpose of reducing mother-to-child HIV transmission. The purpose of the study was to assess characteristics of HIV testing and identify factors associated with HIV counseling and testing. METHODS: A cross-sectional study was carried out comprising 1,658 mothers living in Porto Alegre, Brazil. Biological, reproductive and social variables were obtained from mothers by means of a standardized questionnaire. Being counseling about HIV testing was the dependent variable. Confidence intervals, chi-square test and hierarchical logistic model were used to determine the association between counseling and maternal variables. RESULTS: Of 1,658 mothers interviewed, 1,603 or 96.7% (95% CI: 95.7-97.5) underwent HIV testing, and 51 or 3.1% (95% CI: 2.3-4.0) were not tested. Four (0.2%) refused to undergo testing after counseling. Of 51 women not tested in this study, 30 had undergone the testing previously. Of 1,603 women tested, 630 or 39.3% (95% CI: 36.9-41.7) received counseling, 947 or 59.2% (95% CI: 56.6-61.5) did not, and 26 (1.6%) did not inform. Low income, lack of prenatal care, late beginning of prenatal care, use of rapid testing, and receiving prenatal in the public sector were variables independently associated with a lower probability of getting counseling about HIV testing. CONCLUSIONS: The study findings confirmed the high rate of prenatal HIV testing in Porto Alegre. However, women coming from less privileged social groups were less likely to receive information and benefit from counseling.  相似文献   
996.
Pharmacological and neuroanatomical evidence suggest the involvement of the dopaminergic system in obsessive-compulsive disorder (OCD). Analysis of the 48-bp dopamine receptor D(4) (DRD4) gene polymorphism in a sample of 210 OCD patients and 202 healthy control subjects showed a significant association (chi(2)=27.5, df=6, p=0.0003). This difference was attributable to a lower frequency of allele 4R in OCD patients compared with the control group (chi(2)=9.33, p=0.0027). However, we did not replicate previous findings of an association between the 7R allele and OCD patients with tics. Finally, we analyzed a sub-sample of 86 OCD families. E-TDT analysis in 70 informative parents did not confirm the association observed in our case-control analysis. In conclusion, the current study cannot exclude an association between DRD4 gene and OCD in the largest sample analyzed. However, further studies will be required to confirm if the DRD4 gene is involved in the pathogenesis of this disorder.  相似文献   
997.
Amoxapine is marketed as an antidepressant. However, its in-vitro profile, receptor occupancy and preclinical effects are very similar to atypical antipsychotics. Amoxapine has also shown efficacy as an atypical antipsychotic in open trials. The objective of this study was to compare the antipsychotic and side effect profile of amoxapine and risperidone in a randomised assignment, standardized dosing, double-blind trial of acutely psychotic patients with schizophrenia. A total of 48 schizophrenic patients were enrolled and randomized in a double-blind 6-week trial to receive either risperidone (up to 5 mg/day) or amoxapine (up to 250 mg/day). Positive, negative, affective symptoms and motor side effects were measured using standardized weekly assessments. Prolactin levels were also determined at baseline and at the end of the study. A total of 39 patients (amoxapine, n=22; risperidone, n=21) completed the trial. Both pharmacological treatments, amoxapine 228.0 mg/day (SD=34.6) and risperidone 4.5 mg/day (SD=0.7), showed equivalent improvement in positive, negative, and depressive symptoms. Amoxapine was associated with less EPS and less prolactin elevation than risperidone. These data support previous reports about the efficacy of amoxapine as an atypical antipsychotic. Since amoxapine is off-patent, it may be a valuable low-cost alternative to new atypical antipsychotics, particularly in low-income countries where the majority of the patients are still treated with typical antipsychotics.  相似文献   
998.
The loss of muscle mass consequent to poor muscle regeneration is a common sequela following the injection of Bothrops jararacussu snake venom. Since an intact microvasculature plays a central role in the success of muscle regeneration, the poor muscle regeneration seen after envenomation could be explained by damage to the local microvasculature. In this work, we investigated the pathogenesis of microvessel damage caused by B. jararacussu venom and its correlation with poor muscle regeneration. The right soleus muscle of adult mice was injected with 80 microg of venom and the mice were killed from 2 min to 3 months later. Similarly, the soleus muscle of other mice was injected with 80 microg of bothrosptoxin-I (BthTX-I), a non-vasculotoxic myotoxin. Tissue samples were prepared for analysis by electron (venom only) and light (venom and BthTX-I) microscopy. The extent of revascularization was assessed using light microscopy by examining recanalization of thrombi and calculating the individual capillary-to-fiber-ratio, the number of capillaries around a fiber and the capillary/muscle cell ratio. Microvessel damage by venom started within 5 min and, after 6 h, there was total degeneration of the capillaries with failure of the local microcirculation. The time-course of the ultrastructural lesions suggested that endothelial cells were probably damaged by a direct action of B. jararacussu venom on these cells. The revascularization of muscle damaged by venom, but not by BthTX-I, occurred later and was very poor. These results indicate a central role for vascular lesions in muscle regeneration after damage by B. jararacussu venom.  相似文献   
999.
Tinnitus affects millions of people worldwide, and it signals the presence of several underlying diseases, including hyperinsulinemia. The aim of this study was to evaluate the response to dietary treatment in 80 patients with associated tinnitus and hyperinsulinemia. On the basis of data obtained by a questionnaire, two groups were established: One included patients who followed the prescribed diet; the other group included patients who did not comply with the treatment. The likelihood of improving tinnitus symptoms was fivefold higher in hyperinsulinemic patients who followed the diet than in those who did not (relative risk [RR], 5.34; 95% confidence interval [CI], 1.85-15.37; p < .05). In addition, resolution of tinnitus was reported by 15% of the patients who followed the diet as compared to 0% of those who did not. These findings underscore the importance of including hyperinsulinemia in the routine diagnostic investigation of patients with tinnitus regardless of whether associated with neurosensory dysacusis or vertigo (or both).  相似文献   
1000.
The objective of the present study was to determine the prevalence of the intestinal parasites most commonly found in immunocompromised patients. A group of 111 individuals with acute lymphoid leukaemia (ALL), chronic myeloid leukaemia (CML), human immunodeficiency virus (HIV) and other immunocompromised conditions (principally haematological disorders) was selected. A battery of tests was performed on each individual to identify the presence of parasites (three stool specimens with saline solution and Lugol both directly and by concentration, culture and special staining). No significant differences were found among the frequencies of the different parasites with the several types of immunocompromised conditions. The overall frequencies of potentially pathogenic and opportunistic parasites were 32.4% (36/111) and 9% (10/111) respectively, the most frequently encountered among the latter being Cryptosporidium sp., Microsporidia spp. and Strongyloides stercoralis.  相似文献   
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