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991.
A retrospective study was conducted on 186 patients with differentiated thyroid cancer without metastases who received an ablative dose of 100 mCi (3.7 GBq) iodine-131 after total thyroidectomy. Six months to one year after ablation, 155/186 patients (83%) had a negative scan. Diagnostic scanning with 5 mCi (185 MBq) performed 72 h or 3 months before ablation did not interfere with treatment success compared to patients not submitted to pre-therapy scanning. Pre-ablation cervical uptake values < 2% were associated with a higher ablation efficacy (94%), from 2 to 5% showed 80% success and values > 5%, 60% (p < 0.05). There were no significant differences between the responsive and no responsive groups in terms of age, sex, histological type or size of the primary tumor. 11% of the patients with low stimulated Tg (< 2 ng/ml) presented discrete thyroid bed uptake on follow-up diagnostic scan (< 0.5%) without definitive residual disease and 89% had negative uptake on scan. The patients with Tg > 2 ng/ml presented thyroid bed (10/12) or ectopic (2/12) uptake on follow-up diagnostic scan. An ablative dose of 100 mCi shows a high rate of efficacy, especially when cervical uptake is < 2%; no difference was noted between patients assessed by scan within 72 h or 3 months before treatment and those not scanned; follow-up diagnostic scan can be avoided in low risk patients with stimulated Tg < 2 ng/ml.  相似文献   
992.
The concept of causality is a part of every day life because man has always searched for the why of things as a way of dealing with and adapting to the world. In medicine, one of the central aims of study is identification of the factors or agents that cause disease with the intention of establishing treatments and especially, to apply preventive strategies. In this work, we conducted a brief review of the philosophical positions on causality, its biological models, as well as the tools used in clinical epidemiology to evaluate causal associations.  相似文献   
993.
In a retrospective study to determine rate of patients attaining therapeutic LDL-C goal values with lipid-lowering drugs, 20 specialists and general practitioners were selected who enrolled 120 patients whose lipids were measured after at least 12 weeks of treatment. They were grouped in three categories: group A (absolute risk of CHD in 10 years <10%); group B, with 10-20% risk, and group C, with >20% risk. Goal LDL-C values were <160 mg/dL for group A, <130 for group B, and <100 for group C. Mean age was 57 +/- 12 years, 59% were males, and 51% were in group C; 83% took statins, 12% fibrates alone, and 5%, combinations. Atorvastatin and simvastatin were the most used drugs, at medium doses (mean 12 and 27 mg/day). LDL-C was reduced 25%; overall, 22% of patient doses were adjusted. Therapeutic goals were attained in 29% with initial doses and 42% at the end of study. Goal values were better attained in groups with lower risk. No differences were noticed among distinct physician categories. Data show poor compliance with international guidelines and insufficient attainment of therapeutic goals.  相似文献   
994.
OBJECTIVE: To determine the presence of proteins related to proliferation (Ki-67) and apoptosis (Bcl-2, p53) in endometrial polyps and normal endometrium during the menstrual cycle. DESIGN: Retrospective study using paraffin embedded tissue. SETTING: Hospital affiliated to the university. POPULATION: Premenopausal patients with endometrial polyps. METHODS: Seventy-eight premenopausal patients in different phases of the menstrual cycle were submitted to polypectomy using the Bettocchi hysteroscope. Immunohistochemistry was used to detect the expression of these proteins in endometrial polyps. One hundred and eighteen normal endometrial biopsies were used as controls. MAIN OUTCOME MEASURES: Detection of Bcl-2 and Ki-67 expression by immunohistochemistry. RESULTS: In endometrial polyps, Ki-67, p53 and Bcl-2 expression was detected with more frequency during the proliferative than during the luteal phase of the cycle. Similar findings were observed in the normal endometrium. CONCLUSION: Endometrial polyps undergo cyclic changes in the expression of their proteins related to proliferation and apoptosis during the menstrual cycle, similar to those of the cycling endometrium.  相似文献   
995.
OBJECTIVE: This study investigates the effect of routine visits for dental check-up on tooth loss. METHODS: In a cross-sectional study of university employees, the Rio de Janeiro Pró-Saúde Study, tooth loss was measured as the reported number of missing teeth and routine dental visit as the reported pattern and frequency of visits to the dentist. RESULTS: Data were obtained from 4,030 individuals (91% of eligible subjects). Odds ratio of excessive tooth loss ("many" or "all" teeth lost) was 2.20 (95% confidence interval [CI]=1.79, 2.72) for subjects who reported visiting the dentist only when in trouble and 1.17 (95% CI=0.90, 1.51) for subjects who reported visiting for routine dental checks every two years or less frequently, compared with those who reported visiting for dental checks at least annually, after controlling for age, sex, education, income, race, smoking, and diet. CONCLUSIONS: There was a positive effect of routine visits for dental check-up on maintaining teeth. This effect was the same for one year and two years or longer intervals between check-ups.  相似文献   
996.
Rapid orthodontic extrusion is indicated for cases involving biological space invasion of the periodontal ligament in which the surgical increase of the clinical crown can compromise esthetics or the support of the adjacent teeth. This article presents the case report of a tooth with radicular perforation 1.0 mm below the bone crest. A procedure to restore the biological distances was necessary. Rapid orthodontic extrusion of the affected tooth, with anchorage in the adjacent osseointegrated implants, was selected.  相似文献   
997.
The purpose of this study was to compare the depth of sealer penetration into dentinal tubules by three root-filling techniques using light microscopy and digital image processing. Thirty-two maxillary central incisors were prepared. Two teeth were separated for the control group. The rest were divided into three equal groups and obturated as following--G1: lateral condensation; G2: warm vertical compaction of gutta-percha and G3: Thermafil system. Each sample was sectioned longitudinally and prepared for microscopic analysis. A sequence of photomicrographs with magnifications of X50, X200 and X500 were taken. Through digital image analysis and processing, measurements for each field were obtained. A non-parametric ANOVA Kruskal-Wallis analysis was used to determine whether there were significant differences among the groups. Significant differences between G2 and G1 (p = 0.034) and between G3 and G1 (p = 0.021) were identified. There were no significant differences between G2 and G3 (p > 0.05). The results of this research suggest that samples root-filled by thermoplasticised gutta-percha techniques lead to deeper penetration of the root canal sealer into the dentinal tubules.  相似文献   
998.
Dentin hypersensitivity is a common painful condition observed in clinics. Dietary habits have been much associated with its development and persistence during and following periodontal treatment. The aim of this in vitro study was to evaluate the influence of vinegars on the removal of smear layer and exposure of dentinal tubules. Extracted human teeth were submitted to manual scaling with Gracey curettes in order to remove the cementum as well as to form a smear layer. Dentin samples with 3 mm(2) were obtained and distributed into six experimental groups: one control and five types of vinegars (alcohol, apple, rice, white wine and balsamic). Each group included two methods of vinegar application: topical and friction. After routine preparation for SEM analysis, photomicrographs were assessed by a calibrated and blind examiner using an appropriate index system. Kruskal-Wallis test indicated a significant influence of vinegars on smear layer removal. There was a statistically significant difference between groups treated with apple, white and rice vinegars and the control group (p < 0.05). Nevertheless, Mann-Whitney test indicated that removal of smear layer did not vary with the method of application (topical versus friction) for any of the tested substances. We can conclude that the contact of vinegar may remove smear layer and expose dentinal tubules, regardless of the type of application. However, balsamic vinegar was associated with less removal of smear layer after both methods of application.  相似文献   
999.
OBJECTIVE: To determine whether peripheral inflammatory and fibrinolytic markers are elevated in growth hormone-deficient (GHD) adolescents and associated with increased postprandial lipoproteins. STUDY DESIGN: Fifteen GHD children on GH treatment with a chronologic age of 12.7 +/- 2.5 years and 10 untreated GHD adolescents with a chronologic age of 13.0 +/- 2.6 years were studied. Triglycerides (TG), C-reactive protein (CRP), fibrinogen, interleukin 6 (IL-6), and tumor necrosis factor alpha (TNF-alpha) were measured in the fasting state and 4 hours after ingesting a high-fat meal; 15 healthy adolescents served as controls. RESULTS: Fasting and postprandial TG of untreated GHD children were higher than those in treated subjects and healthy controls. Fasting TNF-alpha, CRP, and fibrinogen concentrations of untreated GHD adolescents were higher than those in healthy controls, but similar to those of GH-treated GHD adolescents. Although fibrinogen levels increased after a high-fat meal in GHD adolescents, CRP, TNF-alpha, and IL-6 concentrations did not increase further. Fasting and postprandial TG of untreated GHD adolescents were positively associated with fasting and postprandial CRP, and with postprandial TNF-alpha and IL-6 concentrations. Fasting TG also correlated positively with fasting fibrinogen concentrations in untreated and treated GHD adolescents. CONCLUSIONS: The pronounced inflammatory response seen in GHD adolescents seems to be associated with the presence of elevated levels of fasting and postprandial TG, which may result in an increased susceptibility for premature atherosclerosis.  相似文献   
1000.
We describe 3 previously healthy Costa Rican children who had Listeria monocytogenes meningitis, an uncommon cause of bacterial meningitis beyond the newborn period in normal subjects. Two of them had initial normal brain computed tomography, but all 3 developed acute hydrocephalus at days 7, 3, and 5, respectively. All required immediate ventriculostomy placement and only 1 of 3 survived. L. monocytogenes should be considered among the etiologies of bacterial meningitis in children who do not respond initially to conventional antimicrobial treatment or who deteriorate rapidly.  相似文献   
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