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991.
目的探讨血清中氨基酸的含量变化与短暂性脑缺血和脑梗死体积大小的关系以及对急性缺血性脑血管病的超早期诊断的意义。方法选择发病6h以内的急性缺血性脑血管病(AICVD)患者80例,其中脑梗死(CI)组57例,短暂性脑缺血(TIA)组23例,CI组中大体积梗死19例,中体积梗死22例,小体积梗死16例,各取血清进行高效液相色谱法分析测定血清Glu和GABA。结果TIA组的超早期血清中L-Glu、GABA含量高于对照组,低于CI组;CI组超早期血清中L-Glu、GABA含量高于对照组和TIA组;超早期梗死灶体积大小与血清中L-Glu、GABA含量呈正相关,含量越高,梗死灶体积越大。结论患者血清中L-Glu、GABA含量高低,对急性缺血性脑血管病的超早期诊断有一定的临床价值。  相似文献   
992.
993.
This study investigated the prevalence of specific Toxoplasma gondii IgG in pregnancy, the incidence of congenital toxoplasmosis and the prevalence trend of T. gondii infection among pregnant Polish women between 1998 and 2003. The study population comprised 4916 women who were admitted to the Polish Mother's Memorial Hospital Research Institute in Łódź. Their sera were tested for specific IgG and IgM antibodies to T. gondii, and the incidence of T. gondii infection was calculated from the increase in prevalence rates of IgG antibodies in various age groups. Specific IgG antibody was found in 41.3% (95% CI 39.9–42.7) of pregnant women, and the prevalence of IgG increased with age. The linear trend was significant (p <0.001), with an annual seroconversion rate of 0.7% (95% CI 0.004–0.010). The risk of primary infection was estimated to be 0.5% for 9 months, i.e., an incidence of 5/1000 pregnancies. Assuming a 30% maternofetal transmission rate, 1.5/1000 neonates were infected in utero. Seroprevalence during the 6-year study period decreased from 45.4% in 1998 to 39.4% in 2003, with a yearly decline in prevalence of 1.0% (p 0.02). The most important contributory factor to this decline was the group of women aged 19–29 years, among whom seroprevalence decreased significantly (p 0.007). Specific IgM was found in 244 (4.9%) women.  相似文献   
994.
股骨头骨骺缺血再灌注模型的建立   总被引:9,自引:1,他引:8  
目的:建立缺血再灌注引起幼年兔股骨头骨骺细胞损伤的模型。方法:取12只1kg左右幼年新西兰兔,月龄,性别不限。切开兔髋关节囊,切断圆韧带,显露股骨颈,取皮筋对股骨颈进行加压,皮筋拉力约0.5kg,阻断股骨头骺动静脉血供6h、24h。松开皮筋分别恢复血供6h、24h、168h后取兔股骨头标本。结果:在取标本前进行同位素骨扫描及腹主动脉造影,证实缺血及再灌注有效。常规HE染色及胶原染色病理切片显示:单纯股骨头骨骺缺血6h骨骺骨细胞变性不明显,缺血24h组骨骺骨细胞变性;缺血24h股骨头再灌注168h后骨细胞明显坏死。结论:缺血再灌注可加重幼年兔股骨头骨骺骨细胞损伤。  相似文献   
995.
BACKGROUND: The plasma kallikrein-kinin system (PKKS) has been implicated in cardiovascular disease, but activation of the PKKS has not been directly probed in individuals at risk of coronary heart disease (CHD) or stroke. OBJECTIVE: To determine the involvement of the PKKS, including factor XI, in cardiovascular disease occurring in a nested case-control study from the Second Northwick Park Heart Study (NPHS-II). METHODS AND RESULTS: After a median follow-up of 10.7 years, 287 cases of CHD and stroke had been recorded and 542 age-matched controls were selected. When FXIIa-C1 esterase inhibitor (C1-inhibitor) concentrations were divided into tertiles (lowest tertile as reference), the odds ratios (ORs) at 95% CIs for CHD were 0.52 (0.34-0.80) in the middle tertile and 0.73 (0.49-1.09) in the highest tertile (P = 0.01 for the overall difference; P = 0.01 for CHD and stroke combined). For kallikrein-C1-inhibitor complexes, the ORs for stroke were 0.29 (0.12-0.72) and 0.67 (0.30-1.52) in the middle and high tertiles, respectively (P = 0.02). FXIIa-C1-inhibitor and kallikrein-C1-inhibitor complexes were negatively related to smoking and fibrinogen (P < 0.005). FXIa-inhibitor complexes correlated strongly with FXIIa-inhibitor complexes. CONCLUSIONS: Lower levels of inhibitory complexes of the PKKS enzymes and particularly of FXIIa contribute to the risk of CHD and stroke in middle-aged men. This observation supports the involvement of the PKKS in atherothrombosis.  相似文献   
996.
Apolipoprotein E4 (apoE4), the major genetic risk factor of Alzheimer's disease (AD), is associated with enhanced brain inflammation. Genome-wide gene expression profiling was employed to study the effects of apoE genotype on hippocampal gene expression in LPS-treated mice, transgenic for either apoE4 or the AD benign allele, apoE3. This revealed that the expression of inflammation-related genes following intracerebroventricular injection of LPS was significantly higher and more prolonged in apoE4 than in apoE3 transgenic mice. Clustering analysis revealed gene clusters which responded differently in apoE4 and apoE3 mice and were significantly enriched in NF-kappaB response elements. Direct measurement of NF-kappaB-regulated genes revealed that their extent of activation was greater in the apoE4 mice. Immunohistochemistry experiments revealed that microglial and NF-kappaB activation were more pronounced in apoE4 than in apoE3 mice. These findings suggest that the increased brain inflammation in apoE4 mice is related to disregulation of NF-kappaB signaling pathway.  相似文献   
997.
目的 了解四川省大骨节病病情现状.方法 对20个大骨节病病区县进行儿童右手X线检查、成人大骨节病病情调查,采集儿童发样及当地主食粮样进行含硒量检测.结果 儿童临床检出率平均为1.02%;X线检出率平均为2.12%(0~13.16%),其中10.00%及以上的病区村有13个.成人临床检出率平均为27.02%(3.34%~53.08%),其中Ⅰ度16.73%、Ⅱ度7.79%、Ⅲ度2.49%.儿童发硒水平平均为(0.289±0.079)mg/kg,粮食硒水平平均为(0.023±0.021)mg/kg.结论 四川省大部分地区儿童大骨节病病情处于控制或基本控制范围,但局部地区尚处于较高新发病水平,成人大骨节病病情较为严重.  相似文献   
998.
A male patient of 60 years presented with a swelling in the left groin of 10 months duration. Past records showed bilateral lumbar sympathectomy and omentopexy done 20 and 6 years back, respectively, for Buerger’s disease. Abdominal examination revealed a huge hernial swelling in the left groin extending from the symphysis pubis to anterior superior iliac spine measuring 25 × 18 cm. On exploration, the contents were intestines and omentum, which were coming out through a defect of 5 × 3 cm in the lower fibers of the conjoint muscle 4 cm cephalad to the deep ring, a finding which made the final diagnosis as an incisional hernia. We present this interesting case as a very rare complication of omentopexy, probably not reported previously, and an unusual case of an incisional hernia presenting as an inguinal hernia which is very difficult to diagnose unless encountered before. Its rarity and clinical challenge is highlighted.  相似文献   
999.
目的应用超声多普勒方法评价冠心病患者的左室整体舒张功能及舒张功能障碍的发生率,探讨舒张功能障碍在冠心病无创诊断中的价值。方法对入选病人行常规检查,同时进行二尖瓣血流频谱、肺静脉血流频谱及二尖瓣环组织多普勒检查,对比临床标准与舒张功能障碍标准对冠心病的诊断率。结果舒张功能障碍标准对冠心病的检出率显著高于临床标准。结论舒张功能检查可作为冠心病诊断的初筛检查。  相似文献   
1000.
CT导引下胸部病变穿刺活检不同方法的临床探讨   总被引:2,自引:1,他引:1  
目的探讨胸部病变穿刺活检联合同轴针吸对提高阳性率减少并发症的价值。方法回顾性分析CT导引下106例胸部病变三种不同穿刺方法的阳性率及并发症。结果单纯针吸组32例,检出恶性病变23例,良性4例,阳性率为84.3%,并发症为15.6%;单纯活检组27例,检出恶性病变15例,良性7例,阳性率为81.5%,并发症为48.1%;活检同轴针吸组47例,检出恶性病变28例,良性15例,阳性率91.5%,并发症为29.7%。结论活检联合同轴针吸是提高阳性率减少并发症的较好的活检方法,它既弥补了活检的缺点,又集中了针吸的优点,是值得推广的活检方法。  相似文献   
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