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671.
目的:利用整字、部件与笔画的启动探讨笔画构成汉字过程中整体与部分的关系。方法:实验于2005-09/12在北京师范大学认知神经科学与学习国家重点实验室完成。受试者23人,实验材料为能够组成笔画数为四划、五划的高频汉字(字频〉196次/106)的笔画组共128组,所有笔画组的空间排列均符合笔顺,将所有笔画组平均分配到整字启动、部件启动、笔画启动、无启动4个实验组内。每个实验组内包含16个四划笔画组与16个五划笔画组。材料中增加实验刺激总数25%的笔画组作为填充材料,填充材料不能组成汉字。实验中要求受试者用给出的笔画组(四划或五划)构成汉字,判断是否能够组成一个真实的汉字。 结果:整字、部件、笔画与无启动条件的反应时分别为1445,1596,1484,1555ms。错误率分别为5.5%,12.5%,8.6%,14.7%。整字启动条件下反应时最短,错误率最低。笔画启动条件下其次。部件启动与无启动条件下反应时较长,错误率较高。 结论:在笔画构成汉字的过程中,主要以整字加工为主,笔画加工也起到了重要作用。  相似文献   
672.

Background

It is largely unknown what medication is used by patients with lower respiratory tract infection (LRTI).

Aim

To describe the use of self-medication and prescribed medication in adults presenting with LRTI in different European countries, and to relate self-medication to patient characteristics.

Design and setting

An observational study in 16 primary care networks in 12 European countries.

Method

A total of 2530 adult patients presenting with LRTI in 12 European countries filled in a diary on any medication used before and after a primary care consultation. Patient characteristics related to self-medication were determined by univariable and multivariable logistic regression analysis.

Results

The frequency and types of medication used differed greatly between European countries. Overall, 55.4% self-medicated before consultation, and 21.5% after consultation, most frequently with paracetamol, antitussives, and mucolytics. Females, non-smokers, and patients with more severe symptoms used more self-medication. Patients who were not prescribed medication during the consultation self-medicated more often afterwards. Self-medication with antibiotics was relatively rare.

Conclusion

A considerable amount of medication, often with no proven efficacy, was used by adults presenting with LRTI in primary care. There were large differences between European countries. These findings should help develop patient information resources, international guidelines, and international legislation concerning the availability of over-the-counter medication, and can also support interventions against unwarranted variations in care. In addition, further research on the effects of symptomatic medication is needed.  相似文献   
673.
Summary. Background: This study was conducted to assess whether newly developed recombinant clotting factor concentrates enable the reversal of dilutional coagulopathy. Methods: In 50 anesthetized pigs, ~ 60% of the blood volume was withdrawn and replaced with hydroxyethyl starch. Pigs were randomized to receive either 200 mg kg?1 fibrinogen (n = 10), fibrinogen and 35 IU kg?1 prothrombin complex concentrate (PCC) (n = 10), fibrinogen and 4 mg kg?1 recombinant human factor II (rhFII) concentrate (n = 10), fibrinogen and a three‐factor combination (3F) of 4 mg kg?1 rhFII, 0.006 mg kg?1 recombinant human FVIIa and 0.32 mg kg?1 recombinant human FX (n = 10), or saline (n = 10). Thereafter, a standardized liver laceration was performed to induce uncontrolled hemorrhage. Survival time and blood loss were determined, and standard coagulation tests and thrombelastometry were performed. Results: Fibrinogen combined with rhFII or PCC improved survival. Blood loss was significantly decreased in all groups as compared with the animals receiving saline. Clotting time was significantly shortened in the animals treated with fibrinogen and PCC, as well as in those treated with fibrinogen and 3F. One animal died after administration of fibrinogen and PCC. Conclusion: Following hemodilution, a combination of fibrinogen and PCC, rhFII or 3F enhances coagulation and final clot strength. Mortality was reduced statistically significantly only in the animals treated with fibrinogen and rhFII or PCC, whereas administration of the combination of fibrinogen and PCC caused a fatal thromboembolic complication. The combination of fibrinogen and rhFII might be effective in reversing dilutional coagulopathy and may reduce blood loss in cases of dilutional coagulopathy.  相似文献   
674.
675.

Background  

Methamphetamine (MA) use continues to be a major public health concern in many urban settings. We sought to assess potential relationships between MA use and individual, social, and structural HIV vulnerabilities among sexual minority (lesbian, gay, bisexual or transgendered) drug users.  相似文献   
676.

Background and purpose

As a combination of 5-HT selective reuptake inhibitor (SSRI) with 5-HT1A receptor antagonism may yield a rapidly acting antidepressant, WAY-211612, a compound with both SSRI and 5-HT1A receptor antagonist activities, was evaluated in preclinical models.

Experimental approach

Occupancy studies confirmed the mechanism of action of WAY-211612, while its in vivo profile was characterized in microdialysis and behavioural models.

Key results

WAY-211612 inhibited 5-HT reuptake (Ki = 1.5 nmol·L−1; KB = 17.7 nmol·L−1) and exhibited full 5-HT1A receptor antagonist activity (Ki = 1.2 nmol·L−1; KB = 6.3 nmol·L−1; Imax 100% in adenyl cyclase assays; KB = 19.8 nmol·L−1; Imax 100% in GTPγS). WAY-211612 (3 and 30 mg·kg−1, po) occupied 5-HT reuptake sites in rat prefrontal cortex (56.6% and 73.6% respectively) and hippocampus (52.2% and 78.5%), and 5-HT1A receptors in the prefrontal cortex (6.7% and 44.7%), hippocampus (8.3% and 48.6%) and dorsal raphe (15% and 83%). Acute or chronic treatment with WAY-211612 (3–30 mg·kg−1, po) raised levels of cortical 5-HT approximately twofold, as also observed with a combination of an SSRI (fluoxetine; 30 mg·kg−1, s.c.) and a 5-HT1A antagonist (WAY-100635; 0.3 mg·kg−1, s.c). WAY-211612 (3.3–30 mg·kg−1, s.c.) decreased aggressive behaviour in the resident-intruder model, while increasing the number of punished crossings (3–30 mg·kg−1, i.p. and 10–56 mg·kg−1, po) in the mouse four-plate model and decreased adjunctive drinking behaviour (56 mg·kg−1, i.p.) in the rat scheduled-induced polydipsia model.

Conclusions and implications

These findings suggest that WAY-211612 may represent a novel antidepressant.  相似文献   
677.
BACKGROUND: Variation in the expression of plasminogen activator inhibitor type-1 (PAI-1) is associated with many human diseases, including several types of cancer. In particular, tumor cell overexpression of PAI-1 has been found to inhibit prostate cancer tumor growth, angiogenesis, and metastasis in mouse models. Normal host cell expression of PAI-1 is influenced by the 4G/5G insertion/deletion polymorphism in the promoter region of the PAI-1 gene. To evaluate the effect of PAI-1 expression on cancer development, we examined the association of the 4G/5G polymorphism in a sibling-based case-control study of prostate cancer. METHODS: One thousand one hundred thirty seven subjects, 655 cases, and 482 sibling controls from 526 families, were recruited from the major medical institutions in the greater Cleveland, OH area and from the Henry Ford Health System, Detroit, MI. A Cox age-of-onset model with robust variance estimation was used to evaluate the association between the PAI-1 4G/5G polymorphism and prostate cancer. RESULTS: No association was observed between the PAI-1 4G/5G polymorphism and prostate cancer in the entire sample. We did, however, identify a statistically significant association between the PAI-1 4G/5G polymorphism and prostate cancer in subjects with a family history of this disease (OR = 1.28, 95% CI 1.02-1.61, P-value = 0.036). The PAI-1 5G/5G genotype, associated with lower PAI-1 expression, appears to drive this result as it was associated with an increased risk of prostate cancer and an earlier mean age of onset compared to those with the 4G/4G genotype (OR = 1.83, 95% CI 1.12-2.99) while the 4G/5G genotype group did not show a significant difference in prostate cancer risk compared to the 4G/4G genotype group (OR = 0.98, 95% CI 0.75-1.28). CONCLUSIONS: These observations suggest that the 4G/5G polymorphism in PAI-1 may explain some of the increased risk and earlier mean age of onset of prostate cancer due to a positive family history.  相似文献   
678.
目的:观察并比较黑醋与红曲单用及联用对中国中老年人降低血脂的效能。方法:试验于2003-10/11在大连医科大学中日合作医药科学研究所进行。选择30名年龄为45 ̄65岁的中老年人。30名受试者被随机分为3组,每组10人,分别服用黑醋丸6粒,红曲丸6粒或黑醋 红曲丸6粒,1次/d,连续4周;3种膳食补充剂黑醋丸、红曲丸及黑醋 红曲丸由含有不同剂量的黑醋固形物、红曲粉末K-F、柠檬酸钠、大豆油、蜂蜡、脂肪酸甘油脂组成(由日本国第一药品工业株式会社提供)。各组服用剂量分别为每天黑醋固形物360mg,红曲粉72mg及黑醋固形物360mg 红曲粉72mg。服用2和(或)4周后,检测血脂和血糖,同时用血清样品检测肝功与肾功能。实验结果用SPSS统计软件进行方差分析。结果:30名中老年人全部进入结果分析。①受试者连续3d每日营养素摄入量:3组之间热量、胆固醇、膳食纤维、宏量或微量营养素摄入量差距均无显著性。②血清脂质浓度和计算的脂质比:2,4周血清三酰甘油含量,黑醋 红曲组低于基础值(分别下降(24.6±4.9)%,(27.6±3.4)%,P<0.05);红曲组与基础值比较,差异无显著性[分别下降(6.5±3.4)%,(11.6±4.5)%];黑醋组与基础值比较,差异无显著性[分别下降(10.2±7.3)%,(12.4±8.2)%]。2,4周血清胆固醇、低密度脂蛋白胆固醇含量,黑醋 红曲丸、红曲丸和黑醋丸组均比基础值降低,差异无统计学意义。3种膳食补充剂对血清高密度脂蛋白胆固醇及计算的脂质比值无明显改变。血糖含量无变化。未发现对受试对象产生明显不良反应。结论:服用黑醋 红曲丸能明显降低受试者血清三酰甘油含量。黑醋与红曲合用对高脂血症者可能有健康效益。  相似文献   
679.
子宫内膜异位症患者血清细胞因子水平的测定程凯灵令狐华子宫内膜异位症(EMS)是妇科常见病。国内外学者的研究表明,免疫学的变化在该病的病理生理学中有重要意义。本研究通过酶联免疫吸附试验(ELISA),对EMS患者血清细胞因子[白细胞介素(IL)-6、I...  相似文献   
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