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71.
The use of pregnancy‐specific multivitamin supplements is widely recommended to support maternal homeostasis during pregnancy. Our objective was to investigate whether multivitamin use during pregnancy is associated with a reduced risk of pre‐eclampsia. The effect of multivitamin use on incidence of pre‐eclampsia in lean and overweight/obese women was analysed using data collected between 2006 and 2011 as part of the Environments for Healthy Living Project, Griffith University, Australia. A total of 2261 pregnancies were included in the analysis with pre‐eclampsia reported in 1.95% of subjects. Body mass index (BMI) ≥ 25 was associated with a 1.97‐fold [95% confidence interval (CI): 0.93, 4.16] increase in pre‐eclampsia risk. First trimester multivitamin use was reported by 31.8% of women and after adjustment, was associated with a 67% reduction in pre‐eclampsia risk (95%CI: 0.14, 0.75). Stratification by BMI demonstrated a 55% reduction in pre‐eclampsia risk (95%CI: 0.30, 0.86) in overweight (BMI: 25–29.9) and 62% risk reduction (95%CI: 0.16, 0.92) in obese (BMI: ≥30) cohorts that supplemented with multivitamins in the first trimester of pregnancy. This finding may be particular to the Australian population and reflect inherent nutritional deficits. First trimester folate supplementation was found to reduce pre‐eclampsia incidence [adjusted odds ratios (AOR) 0.42 95%CI: 0.13, 0.98] and demonstrated significance upon stratification by overweight status for women with BMI >25 (AOR 0.55 95%CI: 0.31, 0.96). These results support the hypothesis that multivitamin supplementation may be beneficial in reducing the incidence of pre‐eclampsia during pregnancy and be of particular importance for those with a BMI ≥25.  相似文献   
72.
Objective: In preeclampsia, changes in fetal hemodynamics can be detected 2–3 weeks earlier than any changes in cardiotocogram. Thus, these Doppler changes can be used to predict perinatal outcome. The present study is planned to assess the accuracy of the middle cerebral artery to umbilical artery (UA) pulsatility index (PI) and resistance index (RI) in predicting adverse perinatal outcome in pregnancies complicated by preeclampsia. Methods: Total of 115 and 108 pregnant women were included in preeclampsia and control group, respectively. Weekly Doppler study was done in both groups starting from 30 weeks till 36 weeks or delivery, whichever is later. Results: Mean gestational age at delivery was 250 ± 13 and 273 ± 8 days, respectively, in preeclampsia and control group (p < 0.01). Thirty-four babies in preeclampsia group had been admitted to nursery; out of which three died (p < 0.01). On receiver operating characteristic analysis, MCA /UmA PI ratio and MCA /UmA RI ratio had sensitivity of 9% and 9.7% and specificity of 98% and 96.6%, respectively, for predicting adverse perinatal outcome. Conclusion: Doppler indices of MCA and Um A are significantly abnormal in preeclampsia. But on diagnostic statistical analysis they have good specificity but low sensitivity for detecting adverse perinatal outcome.  相似文献   
73.
74.
Chondrosarcomas are malignant tumours of cartilaginous origin. They range from a well-differentiated growth resembling a benign cartilage tumour to a high-grade malignancy with aggressive local behaviour and the potential to metastasize. Only 5% to 10% of chondrosarcomas are known to occur in the head and neck region. A case of chondrosarcoma of the anterior region of the mandible is presented, along with a review of the relevant literature.  相似文献   
75.
A three-year-old boy was investigated for inexplicable incessant crying. On examination, his left wrist was mildly swollen (three to four months) and sensitive. Exploration and carpal tunnel decompression of the left wrist with incisional biopsy was performed for the presence of a fusiform swelling intimately associated with the median nerve. Histopathology revealed the presence of enlarged nerve bundles admixed with mature fat cells and diffuse fibroblastic proliferation. Three months later, he underwent urgent contralateral carpal tunnel decompression for a similar presentation. The final diagnosis was bilateral fibrolipomatous hamartoma (FLH) of the median nerves causing acute bilateral compression neuropathy.FLH of the median nerve is an extremely unusual cause of acute bilateral carpal tunnel syndrome in a young child presenting with ‘incessant crying’. A comprehensive review of FLH including epidemiology, etiology, clinical presentation, differential diagnosis, imaging, pathology, treatment and prognosis is discussed.  相似文献   
76.

Objective:

Experimental pain models in human healthy volunteers are advantageous for early evaluation of analgesics. All efforts to develop nonsteroidal anti-inflammatory drugs (NSAIDs) which are devoid of gastrointestinal and cardiovascular system effects are still far from achieving a breakthrough. Hence we evaluated the analgesic activity of an ayurvedic drug, Boswellia serrata by using validated human pain models which has shown its analgesic activity both in-vitro and preclinical studies to evaluate the analgesic activity of single oral dose (125 mg, 2 capsules) of Boswellia serrata compared to placebo using mechanical pain model in healthy human subjects.

Materials and Methods:

After taking written informed consent, twelve healthy subjects were randomized (1:1) to receive single oral dose of Boswellia serrata (Shallaki®) 125 mg, 2 capsules or identical placebo in a crossover design. Mechanical pain was assessed using Ugo basile analgesymeter (by Randall Selitto test) at baseline and at 1 hr, 2 hrs and 3 hrs after test drug administration. Pain Threshold force and time and Pain Tolerance force and time were evaluated. Statistical analysis was done by paired t-test.

Results:

Twelve healthy volunteers have completed the study. Mean percentage change from baseline in Pain Threshold force and time with Boswellia serrata when compared to placebo had significantly increased [Force: 9.7 ± 11.0 vs 2.9 ± 3.4 (P = 0.05) and time: 9.7 ± 10.7 vs 2.8 ± 3.4 (P = 0.04)] at third hr. Mean Percentage change from baseline in Pain Tolerance force and time with Boswellia serrata when compared to placebo had significantly (P ≤ 0.01) increased at 1 hr, 2 hrs and 3 hrs.

Conclusion:

In the present study, Boswellia serrata significantly increased the Pain Threshold and Pain Tolerance force and time compared to placebo. Both study medications were well tolerated. Further multiple dose studies may be needed to establish the analgesic efficacy of the drug.KEY WORDS: Boswellia serrata, human pain models, randall selitto test, ugo basile analgesymeter  相似文献   
77.
ABSTRACT. Background: This study sought to determine the relationship between the frequency of current marijuana and alcohol use and cigarette quit attempts in male and female adolescent smokers. Methods: Data from a cross-sectional survey of health behaviors in high-school-aged adolescents were analyzed. Current cigarette smokers (n = 804) who reported use of at least 1 cigarette in the past month were divided into those with and without a history of at least 1 quit attempt (a self-reported episode of trying to “stop smoking”). Logistic regression models were fit to describe the association between the frequency of marijuana/alcohol use and a history of cigarette quit attempts. Results: Among the total sample, higher-frequency marijuana use (more than 6 times in the past 30 days) and frequent binge drinking (more than 5 days of binge drinking in the past 30 days) decreased the odds of having a past cigarette quit attempt (higher-frequency marijuana: adjusted odds ratio [AOR] = 0.56, 95% confidence interval [CI] = 0.36–0.86; frequent binge drinking: AOR = 0.49, 95% CI = 0.29–0.83). A significant gender interaction was observed for the relationship between higher-frequency marijuana use and a history of cigarette quit attempts (P = .03), with decreased odds in boys (AOR = 0.41, 95% CI = 0.22–0.77) but not in girls (AOR = 0.71, 95% CI = 0.37–1.33). Conclusions: Adolescent smokers who report higher-frequency marijuana use or frequent binge drinking have a decreased likelihood of a history of a cigarette quit attempt. The gender-related association between higher-frequency marijuana use and a history of quit attempts suggests that boys with greater substance use may need particularly intensive support to initiate quit attempts.  相似文献   
78.
Chlorotoxin is a small 36 amino-acid peptide identified from the venom of the scorpion Leiurus quinquestriatus. Initially, chlorotoxin was used as a pharmacological tool to characterize chloride channels. While studying glioma-specific chloride currents, it was soon discovered that chlorotoxin possesses targeting properties towards cancer cells including glioma, melanoma, small cell lung carcinoma, neuroblastoma and medulloblastoma. The investigation of the mechanism of action of chlorotoxin has been challenging because its cell surface receptor target remains under questioning since two other receptors have been claimed besides chloride channels. Efforts on chlorotoxin-based applications focused on producing analogues helpful for glioma diagnosis, imaging and treatment. These efforts are welcome since gliomas are very aggressive brain cancers, close to impossible to cure with the current therapeutic arsenal. Among all the chlorotoxin-based strategies, the most promising one to enhance patient mean survival time appears to be the use of chlorotoxin as a targeting agent for the delivery of anti-tumor agents. Finally, the discovery of chlorotoxin has led to the screening of other scorpion venoms to identify chlorotoxin-like peptides. So far several new candidates have been identified. Only detailed research and clinical investigations will tell us if they share the same anti-tumor potential as chlorotoxin.  相似文献   
79.
80.
W J Deery  C S Rani 《Endocrinology》1991,128(6):2967-2975
The mechanism and site(s) of the defect responsible for desensitization to hormone stimulation of adenylyl cyclase (AC) vary with cell type. Plasma membrane preparations were assayed after treatment of primary cultured dog thyroid cells to determine the role of the TSH receptor, stimulatory and inhibitory guanine nucleotide binding proteins (Gs and Gi), and catalytic unit in AC desensitization. Exposure of cells to TSH or the phorbol ester, 12-O-tetradecanoyl-phorbol-13-acetate (TPA), caused time dependent decreases in TSH-stimulated AC and [125I]TSH binding with approximately 50% decreases seen after 18 h; Bt2cAMP was unable to reproduce the TSH effect. Whereas TSH treatment caused concomitant decreases (approximately 25%) in both cyclase activity and [125I]TSH binding after 2 h, TPA treatment decreased AC activity after 6 h and binding only after 18 h. The protein kinase C inhibitor, H-7, prevented TPA-induced but not TSH-induced effects on AC and hormone binding. Membrane AC activation by cholera toxin or forskolin was not altered by 18 h pretreatment of cells with TSH or TPA, indicating that these agents had no apparent effect on intrinsic functionality of either Gs or the catalytic unit. TSH or TPA pretreatment of cells reduced subsequent toxin-mediated AD[32P]-ribosylation of Gs and Gi in isolated membranes. However, the TSH- and TPA-induced decreases in AD[32P]-ribosylation and desensitization do not appear to be due to endogenous ribosylation of G proteins, since treatment of cells with pertussis toxin, for example, to endogenously ribosylate Gi, both increased TSH-stimulated AC activity and failed to affect the ability of TSH or TPA to desensitize. Thus, in this system, although specific hormone-induced AC desensitization and receptor down-regulation conform to several aspects of classic homologous processes, similar effects are also induced by a nonreceptor (phorbol ester) pathway; desensitization, however, can precede down-regulation, possibly due to receptor-Gs uncoupling.  相似文献   
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