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21.
Jim-Shoung Lai T.-N. Wu Saou-Hsing Liou Chen-Yang Shen Chiam-Fang Guu Kquei-Nu Ko Chi. Hsueh-Yun P.-Y. Chang 《International archives of occupational and environmental health》1997,69(4):295-300
Objective: To examine the relationship between ambient lead levels and blood lead levels and to explore the modifiers of the relationship
between ambient lead and blood lead. Method: A cross-sectional study was conducted in two lead battery factories. Blood lead level and ambient lead concentration were
measured for each participant concurrently. A structured questionnaire was administered to collect sociodemographic characteristics
and occupational history. Design: Biological and personal environmental measurements of 219 lead-exposed workers were analyzed by both simple and multiple linear
regression. A regression model was selected for interpretation. Results: A high correlation (r=0.62) between ambient lead (PbA) and blood lead (PbB) was observed. In addition, numerous factors, including age, sex, alcohol
consumption, personal hygiene practice and type of lead exposure, were also found to influence blood lead levels. Although
PbB was highly correlated with PbA, blood lead level may not be effectively lowered by reducing ambient lead level. Based
on the regression coefficients, improvement of hygienic practice was more effective at lowering PbB than reducing ambient
lead level. Good hygienic practice may be the preferential way to reduce lead exposure in current conditions. Conclusion: Education of correct work practice may be more important than engineering control in the developing countries to lower blood
lead levels in lead battery factories.
Received: 28 May 1996/Accepted: 30 August 1996 相似文献
22.
成人原发性肾病综合征血容量与肾素,醛固酮,心钠素的关系 总被引:2,自引:0,他引:2
探讨成人原发性肾病综合征(NS)血容量与肾素、醛固酮及心钠素的关系。方法 应用~(113)mInCl标记转铁蛋白稀释法测定血容量,放免法测定血浆激素水平。对水肿期NS28例、正常26例及其中NS缓解期随访18例进行检测。结果 (1)水肿期NS血容量与正常组无差别,血浆肾素活性(PRA)、血管紧张素Ⅱ(ATⅡ)、醛固酮(Ald)、心钠素(ANP)水平均较正常组高,白蛋白、各激素水平与血容量无显著相关;(2)缓解期与水肿期比较,总的血容量无差异,Ald、ANP显著降低,PRA、ATⅡ则无明显差异;(3)Ald与24小时尿排钠(UNaV)显著负相关。结论 Ald和ANP是NS钠排泄的主要调节因子。 相似文献
23.
Twin study of genetic and environmental effects on lipid levels 总被引:4,自引:0,他引:4
D L O'Connell R F Heller D C Roberts J R Allen J C Knapp P L Steele D Silove 《Genetic epidemiology》1988,5(5):323-341
A study of 106 pairs of monozygotic (MZ) and 94 pairs of dizygotic (DZ) twins tested the hypothesis that part of the previously described genetic influence on blood lipid levels can be ascribed to closer similarities among MZ than among DZ twin pairs in environmental factors that affect lipid levels. Participants were adult twin volunteers (age 17-66; 64 male and 136 female pairs) who were selected from the NH & MRC Twin Registry or were respondents to advertisements. They completed a 4-day weighed food diary from which mean nutrient intake was derived. Information on lifestyle and demographic variables was obtained by questionnaire and a nonfasting blood sample was taken for measures of total, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol and the HDL2 and HDL3 subfractions. Height and weight were measured, and body mass index (BMI) was calculated (kg/m2). Estimates of the heritability of sex-adjusted lipid levels were 0.72 for total cholesterol, 0.79 for HDL cholesterol, 0.69 for HDL2, 0.20 for HDL3, 1.06 for LDL cholesterol, and 0.44 for sex-adjusted BMI. In all cases except for HDL3, genetic variance was statistically significant. After adjusting for the effects of environmental variables in three different ways, the estimates of heritability were somewhat lower for total cholesterol, HDL2, and BMI, and those for HDL cholesterol (borderline) and LDL cholesterol (definitely) remained statistically significant but were decreased. A genetic influence on HDL3 was not found. Adjusted heritability estimates obtained from one method of analysis were 0.35 for total cholesterol, 0.49 for HDL, 0.04 for HDL2, -0.34 for HDL3, 0.66 for LDL, and 0.32 for BMI. These results suggest that the assumptions made in the classical twin study approach are not appropriate when examining genetic effects on lipid levels or BMI, or indeed on any biological variable that may be affected by environmental factors that tend to be more similar in MZ twins than in DZ twins. In these circumstances, more complex models may be needed to differentiate between genetic and environmental influences. 相似文献
24.
对离体不同时间血痕进行肉眼和扫描电镜观察,获得了血痕形态结构变化的初步认识.结果随时间延长,血痕逐渐干燥、龟裂,电镜下纤维蛋白网消失,其超微结构变化观察有助于血痕经过时间的推断. 相似文献
25.
抗—HCV阳性单采浆供血员HGV感染随访研究 总被引:3,自引:0,他引:3
为了解单采浆供血员庚型肝炎病毒(HGV)感染及其转归,对102名抗-HCV阳性单采浆供血员冻存血清进行抗-HGV和HGVRNA检测,对抗-HGV和(或)HGVRNA阳性者作3年随访研究。采用EIA法检测抗-HGV,包被抗原来自HGV不同功能区的合成肽。应用RT-PCR法检测HGVRNA,引物选自HGVNS3区。结果表明,抗-HCV阳性单采浆供血员HGVRNA阳性率为19.61%(20/102),抗-HGV阳性率为17.65%(18/102),HGV感染率(抗HGV和/或HGVRNA阳性)为24.51%(25/102),而对照组仅为0.94%(1/106)。提示单采血浆是HGV感染的重要危险因素。HGVRNA和抗-HGV的3年阴转率分别为35.00%(7/20)和11.11%(2/18),说明HGV感染有慢性携带趋势 相似文献
26.
M. A. El-Kalay M. H. Abdel-Kader† R. Y. Hamzah† S. A. Al-Shirbini† 《Artificial organs》1990,14(3):200-207
Using a plasma separator, it is possible to wash large volumes of whole blood free of plasma proteins in short periods. The novelty, however, is that the same apparatus can be used to reversibly hemolyze and reseal the red blood cells (RBCs) using hypotonic and hypertonic dialysates, respectively. This technique was assessed using the fluorescent exogenous agent uranin (fluorescein sodium). Results indicate that the encapsulation of the RBCs can be completed in under 2 h. The encapsulation efficiency of the RBCs was approximately 80% with a RBC recovery rate of 75%. 相似文献
27.
动态旋转系统构建组织工程化血管模型中血管内皮细胞分泌功能监测 总被引:3,自引:2,他引:1
目的 比较静态和动态旋转系统中构建组织工程化血管模型中血管内皮细胞分泌功能。方法新型可降解材料聚羟基丁酸酯(PHB),用胶原包埋,形成多孔状PHB 胶原管形支架。分离传代、分化人脐静脉内皮细胞,接种于PHB管型支架内腔面,分别在静态、动态旋转系统中培养14 d后,测定血管内皮细胞分泌一氧化氮(NO)、前列环素(PGI2)水平。结果 在动态旋转系统构建组织工程化血管模型中血管内皮细胞分泌NO、PGI2水平显著高于静态系统,在11 d NO分别为(120.52±3.83)μmmol/L、(80.98±5.98)μmmol/L,PGI2分另9为(20.48±1.52)μg/L,(16.59±1.29)μg/L,与静态系统相比,差异有显著性(P<0.05)。结论胶原包埋PHB支架有利于细胞的黏附和生长,可作为组织工程化血管的支架材料。在动态旋转系统构建组织工程化血管模型中血管内皮细胞,具有与正常血管类似的"生理功能"。 相似文献
28.
目的 研究胃癌根治术病人围手术期异体输血外周血单核细胞(PBMCs)白细胞分化抗原40配体(CD40L)表达的变化。方法 胃癌根治术病人30例,随机分为3组,每组10例。A组围术期不输血,B组围术期输入去白细胞的全血,C组围术期输入异体全血。另选10例健康人作为对照。分别在手术前、术后2、5、10 d采外周静脉血5 ml,用Ficoll分离液梯度离心法分离出PBMCs和血浆,将PBMCs置于自身血浆环境中,并在植物血凝素(PHA,20 mg/L)的刺激下进行培养,48 h后收获细胞,用流式细胞术检测CD40L表达。结果 健康人外周血未受PHA刺激时检测不到CD40L的表达,经PHA刺激后CD40L 细胞占CD4 T细胞的百分数为1.7%±0.4%,与三组胃癌病人术前比较差异无显著性(P>0.05)。与术前比较,B组术后2 d PBMCs CD40L表达升高(P<0.05),C组术后各时点升高(P<0.05);与A组比较,B组术后2 d升高(P<0.05),C组术后各时点升高(P<0.05);与B组比较,C组术后各时点升高(P<0.05)。结论 围手术期异体输血可造成免疫抑制,输异体血后CD40L表达增加,且输全血比输去白细胞的全血更明显。围手术期成分输血优于输注全血。 相似文献
29.
Effect of dialysis flux and membrane material on dyslipidaemia and inflammation in haemodialysis patients. 总被引:4,自引:0,他引:4
Christoph Wanner Udo Bahner Renate Mattern Dietmar Lang Jutta Passlick-Deetjen 《Nephrology, dialysis, transplantation》2004,19(10):2570-2575
BACKGROUND: Dyslipidaemia, inflammation and oxidative stress are prominent risk factors that potentially cause vascular disease in haemodialysis patients. Dialysis modalities affect uraemic dyslipidaemia, possibly by modifying oxidative stress, but the effects of dialyser flux and membrane material on atherogenic remnant particles and oxidized low-density lipoproteins (LDL) are unknown. METHODS: We performed a randomized crossover study in 36 patients on haemodialysis to analyse the effect of dialyser flux and membrane material on plasma lipids, apolipoproteins and markers of inflammation and oxidative stress. Stable patients on low-flux dialysis with polysulphone for >/=6 weeks were assigned to high-flux polysulphone or high-flux modified cellulose with similar dialyser surface area and permeability characteristics and crossed over twice every 6 weeks. RESULTS: Thirty patients completed the study per protocol. Treatments with high-flux polysulphone and modified cellulose lowered serum triglyceride (by 20% and 10%, respectively; P<0.05) and remnant-like particle cholesterol by 32% (P<0.001) and 11% (NS) after the first 6 weeks of treatment. Oxidized LDL decreased significantly with high-flux polysulphone, but not with modified cellulose. Apolipoproteins CII and CIII were reduced, whereas the ratio CII/CIII was increased (all P<0.05). Acute-phase proteins and LDL and high-density lipoprotein cholesterol remained unaffected. CONCLUSIONS: This randomized crossover study demonstrates a potent effect of high-flux haemodialysis on uraemic dyslipidaemia. Polysulphone membrane material showed superiority on oxidatively modified LDL, an indicator of oxidative stress in haemodialysis patients. 相似文献
30.
J A Kavle S S Khalfan R J Stoltzfus F Witter J M Tielsch L E Caulfield 《International journal of gynaecology and obstetrics》2006,95(1):24-28
OBJECTIVE: To accurately measure blood loss during childbirth in a developing country. METHOD: The alkaline hematin technique was used to quantify blood lost during delivery and 24 h postpartum in 158 women in Pemba Island, Zanzibar. RESULT: Women were found to lose less blood during childbirth and 24 h postpartum than previously reported. Compared with laboratory values, nurse-midwives approximated blood loss accurately (mean difference, i.e., mean underestimation by nurse-midwives, 4.90 mL); however, their imprecision was greater for higher laboratory values. CONCLUSION: This study may prompt further investigation, as no comparable data exist for developing countries where maternal mortality is high and severe anemia prevalent. 相似文献