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101.
102.
Quantitative analysis of peripheral nerve regeneration using nerve guides is commonly evaluated through histomorphometry and walking track analysis. We conducted a unique assessment of functional sciatic nerve recovery treated with chitosan nerve guides. We used video-gait analysis to evaluate the extent of functional nerve recovery by measuring the ankle angle at different gait cycle phases. We also correlated the gastrocnemius muscle weight measurements and histological analysis to functional nerve recovery. The chitosan group showed increased functional improvement compared to the control groups at the end of a 12-week period ( p < 0.05). Although both control and chitosan angle measurements were lower than those recorded for presurgery animals, the angle measurements significantly improved over the 12-week period. Stance phase duration of the gait cycle was also recorded, which showed a significant increase over the 12-week time period. The muscle weight parameter indicated a significant decrease in muscle atrophy and restoration of functional strength. Histological analysis revealed that the chitosan nerve guide provided significantly increased axonal growth. The functional results indicated that chitosan nerve guides enhanced functional improvement over no repair processes.  相似文献   
103.
The search for a perfect tumour marker, which would be able to distinguish benign from malignant enlargement of prostate accurately, is still not complete. Total Prostate Specific Antigen (TPSA), a good test, has it's own inadequacies but Free Prostate Specific Antigen (FPSA) to TPSA ratio is emerging as a better adjuvant to it. This prospective study was done to verify the utility of FPSA to TPSA ratio in diagnosis of malignancy of prostate and its relationship to Gleason grading (indicating the aggressiveness) of adenocarcinoma of prostate. 100 patients with urinary symptoms, who were above fifty years of age and had prostatic enlargement, formed the study group. TPSA and FPSA were assayed by ELISA method and FPSA to TPSA ratio was calculated. Prostatic biopsy of all the cases was obtained and diagnostic histopathology and Gleason grading (in cases where adenocarcinoma was diagnosed) was done. Sensitivity, specificity, predictive value of positive test and predictive value of negative test for TPSA and FPSA to TPSA ratio were calculated. They were found to be 100%, 76.7%, 74.1% and 100% for TPSA and 82%, 100%, 100%, 89% for FPSA/TPSA ratio. Thus making it very obvious that FPSA to TPSA ratio is an excellent adjuvant to TPSA for diagnosis of malignancy of prostate increasing the specificity and predictive value for positive test. An inverse correlation (correlation coefficient = -0.95) was also found between PSA ratio and aggressiveness of prostate cancer, pointing towards its capability to predict the histological (Gleason) grade of the tumour.  相似文献   
104.
Background: Metformin (MF) (1,1‐dimethylbiguanide HCl) is one of the most commonly used oral antihyperglycemic agents for the treatment of type 2 diabetes mellitus. Recently, MF has been shown to have bone‐sparing properties. The present study is designed to investigate the effectiveness of MF 1% in an indigenously prepared, biodegradable, controlled‐release gel, as an adjunct to scaling and root planing (SRP) in treatment of vertical defects in smokers with generalized chronic periodontitis (CP). Methods: Fifty patients were categorized into two treatment groups: SRP plus 1% MF and SRP plus placebo. Clinical parameters were recorded at baseline and at 3 and 6 months; they included plaque index (PI), modified sulcus bleeding index (mSBI), probing depth (PD), and clinical attachment level (CAL). At baseline and after 6 months, intrabony defect (IBD) fill was radiologically assessed using computer software. Results: Mean PD reduction and mean CAL gain were found to be greater in the MF group than the placebo group at all visits. Furthermore, a significantly greater mean percentage of bone fill was found in the MF group (26.17% ± 6.66%) than the placebo sites (3.75% ± 8.06%) (P <0.001). Conclusion: There was greater decrease in mSBI and PD and more CAL gain with significant IBD fill at vertical defect sites treated with SRP plus locally delivered MF, versus SRP plus placebo, in smokers with generalized CP.  相似文献   
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Evaluation and outcome of patients with syncope   总被引:37,自引:0,他引:37  
W N Kapoor 《Medicine》1990,69(3):160-175
We studied 433 patients with syncope to derive insights into the diagnostic evaluation and outcome of patients with this common problem. This study shows that the etiology of syncope was not found in approximately 41% of patients. When a cause of syncope was determined, it was most frequently established on the basis of initial history, physical examination and an electrocardiogram (EKG). Furthermore, many of the other entities (e.g., aortic stenosis, subclavian steal) were suggested by findings on the history and physical examinations that required directed diagnostic testing. Initial EKG was abnormal in 50% of patients but led to a cause of syncope infrequently (less than 7%). Prolonged electrocardiographic monitoring, which has assumed a central role in the evaluation of syncope, led to a specific cause in only 22% of patients. Other tests were less often helpful in assigning a cause of syncope. At 5 years, the mortality of 50.5% in patients with a cardiac cause of syncope was significantly higher than the 30% mortality in patients with a noncardiac cause or 24.1% in patients with an unknown cause. At 5 years, a mortality of 50.5% in patients with a cardiac cause of syncope was noted. There were 54 actual deaths in this group as compared to 10.7 expected deaths based on 1980-86 mortality data from Allegheny County, PA (standardized mortality ratio = 5.02). At 5 years, a 33.1% incidence of sudden death was noted in patients with cardiac cause of syncope, as compared with 4.9% in patients with a noncardiac cause and 8.5% in patients with an unknown cause. Mortality and sudden death remained significant for the first 3 years after which the survival curves were parallel. A cardiac cause of syncope was an independent predictor of sudden death and mortality. Recurrences were common but were not associated with an increased risk of mortality or sudden death. Major vascular events were also more frequent in patients with cardiac causes of syncope. The results of this study will be helpful in designing future studies to evaluate the usefulness of newer diagnostic techniques. Furthermore, short- and long-term outcome data will be useful in planning intervention strategies in these patients.  相似文献   
109.

Purpose

To compare overall survival and toxicities after yttrium-90 (90Y) radioembolization and chemoembolization with drug-eluting embolics (DEE) in patients with infiltrative hepatocellular carcinoma (HCC).

Materials and Methods

Retrospective review of 50 patients with infiltrative HCC without main portal vein invasion who were treated with 90Y radioembolization (n = 26) or DEE chemoembolization (n = 24) between March 2007 and August 2012 was completed. Infiltrative tumors were defined by cross-sectional imaging as masses that lacked well-demarcated boundaries, and treatment allocations were made by a multidisciplinary tumor board. Median age was 63 years; median tumor diameter was 9.0 cm; and there were no significant differences between groups in performance status, severity of liver disease, or HCC stage. Toxicities were graded by Common Terminology Criteria for Adverse Events v4.03. Overall survival from treatment was assessed by Kaplan-Meier analysis, with analysis of potential predictors of survival with log-rank test.

Results

There was no difference in the average number of procedures performed in each treatment group (DEE, 1.5 ± 1.1; 90Y, 1.6 ± 0.5; P = .97), and technical success was achieved in all cases. Abdominal pain (73% vs 33%; P = .004) and fever (38% vs 8%; P = .01) were more frequent after DEE chemoembolization. There was no significant difference in median overall survival between treatment groups after treatment (DEE, 9.9 months; 90Y, 8.1 months; P = .11).

Conclusions

90Y radioembolization and DEE chemoembolization provided similar overall survival in the treatment of infiltrative HCC without main portal vein invasion. Abdominal pain and fever were more frequent after DEE chemoembolization.  相似文献   
110.
Homogeneous preparations of type I and type II regulatory subunits (RI and RII, respectively) of cAMP-dependent protein kinase (cAMP kinase) were utilized as antigens to obtain isozyme specific antisera. Injections of pure catalytic subunit (C) from the type I isozyme resulted in antisera that reacted with C subunit obtained from either isozyme type. Cross-reactivity of the antisera raised against isolated subunits of the kinase was assessed by immunodiffusion analysis and by measuring the cAMP binding and phosphotransferase activities of the subunits after immunoprecipitation. These antisera were used to localize subunits of type I and type II cAMP kinases in rat skeletal muscle, liver, and adrenal by using indirect immunofluorescence and immunoperoxidase techniques. Specificity of the immunofluorescence was shown by absorption of the antisera with pure homologous antigens. In skeletal muscle, both R and C subunits of the type I and type II cAMP kinases were localized in the area of the sarcoplasmic reticulum and in periodic crossbands. Specific fluorescence for these components was observed in both isotropic and anisotropic band regions of the sarcomere. Densitometric determinations of immunoperoxidase staining revealed a larger amount of RI, RII, and C subunits in the isotropic band than in the anisotropic band regions. In liver, C, RI, and RII subunits were distributed both in cytoplasmic and nuclear areas and along plasma membranes of hepatocytes; however, there were qualitative differences observed among these various subcellular sites. With each antiserum, fluorescence was blocked by prior absorption with homologous antigen. After treatment of rats with glucagon, dramatic changes in the relative distribution patterns of C and RII were noted in the nucleus. In the adrenal gland, RI, RII, and C subunits were localized in both cytoplasmic and nuclear areas, and an apparent redistribution of these subunits occurred after treatment of (dexamethasone-suppressed) rats with ACTH. The application of this immunocytochemical approach provides a tool for examining and monitoring the subcellular distribution of these components of cAMP kinase in biological systems.  相似文献   
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