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41.
Current public health advice is that high ultraviolet radiation (UVR) exposure is the primary cause of Malignant Melanoma of skin (CMM), however, despite the use of sun-blocking products incidence of melanoma is increasing. To investigate the UVR influence on CMM incidence worldwide WHO, United Nations, World Bank databases and literature provided 182 country-specific melanoma incidence estimates, daily UVR levels, skin colour (EEL), socioeconomic status (GDP PPP), magnitude of reduced natural selection (Ibs), ageing, urbanization, percentage of European descendants (Eu%), and depigmentation (blonde hair colour), for parametric and non-parametric correlations, multivariate regressions and analyses of variance. Worldwide, UVR levels showed negative correlation with melanoma incidence (“rho” = −0.515, p < 0.001), remaining significant and negative in parametric partial correlation (r = −0.513, p < 0.001) with other variables kept constant. After standardising melanoma incidence for Eu%, melanoma correlation with UVR disappeared completely (“rho” = 0.004, p = 0.967, n = 127). The results question classical views that UVR causes melanoma. No correlation between UVR level and melanoma incidence was present when Eu% (depigmented or light skin type) was kept statistically constant, even after adjusting for other known variables. Countries with lower UVR levels and more Eu% (depigmented or light skin people) have higher melanoma incidence. Critically, this means that individual genetic low skin pigmentation factors predict melanoma risk regardless of UVR exposure levels, and even at low-UVR levels.  相似文献   
42.
In the search for antiangiogenic agents from medicinal plants used in Vietnam, a methanol extract of the stem barks of Bombax ceiba was found to exhibit a significant antiangiogenic activity on in vitro tube formation of human umbilical venous endothelial cells (HUVEC). Bioactivity-guided fractionation and isolation carried out on this extract afforded lupeol as an active principle. At 50 and 30 microg/mL lupeol showed a marked inhibitory activity on HUVEC tube formation while it did not affect the growth of tumor cell lines such as SK-MEL-2, A549, and B16-F10 melanoma.  相似文献   
43.
百令胶囊在肾移植术后早中期的应用研究   总被引:4,自引:1,他引:4  
为研究百令胶囊在肾移植术后早,中期的免疫抑制作用,将肾移植患者分为3组,A组为百令胶囊+Pred+CsA,B组为百令胶囊+Pred+CsA+AzaC组为Pred+CsA+Aza。结果:1.急性排斥发生情况:A组16.5%(33/200),B组11.79%(33/280),C组16%(16/100),2.肝功能损害情况;A组18.5%,B组为21.07%,C组25%,3.白细胞下降,A组无,B组12  相似文献   
44.
目的 探讨MRI、视诱发电位(VEP)和视野(Vision Field,VF)在视神经炎中的临床应用价值。方法 临床诊断为视神经炎者60例分别行MRI、VEP和视野检查,每例所有检查均在一周内完成,并将检查结果进行统计学处理和分析。结果 MRI阳性率最高(96.67%),其次是视野和VEP(86.96%和75.58%)。同时发现MRI具有定位和一定的鉴别诊断作用。结论 VEP和VF结合MRI检查,三者相辅相成,将有助于视神经炎更早、更准确地诊断和治疗。  相似文献   
45.
46.
Bronchiolitis generally refers to inflammation and/or fibrosis of the non-cartilaginous small airways located approximately from the 8th airway generation down to the terminal and respiratory bronchioles. In contrast to young children, the frequency of small airway infection in adult bronchiolitis appears less frequent and a number of other pathophysiological conditions have been implicated in adult bronchiolitis. However, little information is available on the exact medical burden of bronchiolitis such as its prevalence and comorbidities in the adult population. The aim of this study is to elucidate the prevalence and comorbidities of bronchiolitis. We used the Korea National Health Insurance Service-National Sample Cohort, which provides data for 1,000,000 individuals out of the entire population by 2% stratified random sampling according to age, sex, residential area, and level of household income. We defined the cause of bronchiolitis other than acute infection as a patient with diagnostic code J448 or J684 and over 20 years of age who visited a clinic or hospital in South Korea. Then, 1:1 propensity score matching was performed to define a non-bronchiolitis (control) group to compare the comorbidities and mortality in the 2 groups. The overall prevalence of bronchiolitis was 688 cases/1,000,000 population during the study period (95% confidence interval, 625–751). The most common comorbid clinical condition in adults with bronchiolitis was rhinitis (52.3%), followed by bronchial asthma (52.23%), hypertension (43.69%), gastroesophageal reflux disease (30.56%), sinusitis (28.72%), diabetes (22.77%), and osteoporosis (17.85%). Other common bronchiolitis-associated comorbidities were cerebrovascular disease (16.86%), angina (14.37%), peripheral vascular disease (13.42%), congestive heart failure (11.9%), and malignancy in any organ (10.6%). Healthcare costs for bronchiolitis increased steeply during the same period. Malignancy in any organ was the leading cause of mortality in the patient group, followed by bronchiolitis itself. Further larger prospective multiethnic cohort studies should be carried out in the near future.  相似文献   
47.
48.
The Sn-Ag-Cu (SAC) solder alloys with a low Ag (Ag < 3 wt.%) content have attracted great attention owing to their low cost, increased ability in bulk compliance, and plastic energy dissipation. However, some of their mechanical properties are generally lower than the SAC alloys with a higher Ag content. Adding alloying elements is an effective approach for improving the mechanical properties of the SAC alloys. In this study, the effect of Bi, Sb, and Ti on Sn-1 wt.%Ag-0.5 wt.%Cu (SAC105) solder alloys was investigated. The SAC solders with four compositions: SAC105-1 wt.%Bi, SAC105-1 wt.%Sb, SAC105-1 wt.%Bi-1 wt.%Sb, SAC105-1 wt.%Bi-1 wt.%Sb-0.4 wt.%Ti were prepared. The microstructure and phase compositions were characterized using electron scanning microscopy, and X-ray diffraction. The thermal properties and wettability were also examined. Uniaxial tensile tests and nano-indentation tests were conducted to evaluate the mechanical properties. The results show that adding Bi or Sb could increase the strength of SAC105 alloys mainly due to the solid solution strengthening effect. The creep resistance of SAC105 alloys was also improved with the additions of Bi and Sb. The co-additions of Bi and Sb into SAC105 alloys exhibit an enhanced creep resistance than that calculated by the theoretical calculation. The further addition of Ti into SAC105-1Bi-1Sb alloys demonstrated a much-improved creep resistance, which could be attributed to the synergistic effects of both solid solution strengthening and the precipitation hardening effects.  相似文献   
49.
目的 比较超声检查和病理测量甲状腺乳头状癌(papillary thyroid carcinoma,PTC)肿瘤大小的差异,并分析其临床意义。方法 选取2012年6月~2014年6月杭州市第一人民医院收治的PTC 114例(共122枚癌灶),所有癌灶大小先后通过术前超声检查和术后组织病理测量确定,采用Pearson相关分析、配对t 检验和Bland-Altman作图评价两种方法测量肿瘤大小的差异性和一致性。结果  Pearson相关显示两种方法测量的肿瘤最大径存在显著正相关(r =0.957,P =0.000)。配对t 检验显示肿瘤的超声最大径(8.24±5.06)mm与病理最大径(7.79±4.75)mm存在显著性差异。Bland-Altman分析显示,两种方法测量的肿瘤最大径的差值绝对值介于0~6.5 mm之间,平均(1.03±1.14)mm,差值的一致性界限(l imit s of agreement,LoA)为-2.41 mm~3.33 mm,LoA的95%置信区间为-2.87 mm~3.78 mm,LoA置信区间范围内差值的最大绝对值为2.9 mm。结论 超声检查和病理测量PTC的肿瘤大小存在显著差异,两者的一致性欠佳,临床实践中应引起重视。  相似文献   
50.
目的:筛选火绒草中的抗炎活性部位。方法:采用系统溶剂法按照极性由低到高的顺序分离得到火绒草石油醚提取物、乙酸乙酯提取物、正丁醇萃取物、水提取物。采用酶联免疫法(ELISA)建立花生四烯酸(AA)的5-脂氧合酶(5-LOX)体外代谢途径,检测火绒草提取物抑制5-LOX活性的能力。结果:火绒草乙酸乙酯提取物对5-LOX活性有76.92%强度的抑制作用。结论:火绒草乙酸乙酯提取物具有较强的抗炎活性,可作为潜在的抗炎活性成分筛选药物。  相似文献   
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