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41.
冠心病病变范围与载脂蛋白E基因多态性及血脂分布的关系 总被引:2,自引:0,他引:2
目的 :探讨冠心病 (CHD)病变范围与载脂蛋白E(apoE)基因多态性及血脂分布的关系。 方法 :用酚氯仿抽提核酸法从凝血块中分离DNA ,用多聚酶链式反应 限制性片段长度多态性 (PCR RFLP)方法对新疆乌鲁木齐地区维、汉两民族人群中 10 2例CHD患者和 5 1例对照组人群进行apoE基因多态性 (由ε2、ε3和ε4决定的E2 / 2、E3/ 3、E4 / 4、E4 / 2、E4 / 3和E3/ 2 )HhaI酶切研究。结果 :①CHD组apoE之ε2 ,ε3和ε4等位基因频率分别为 0 .0 735± 0 .2 15 7,0 .774 5± 0 .3117和 0 .15 2 0± 0 .2 4 16 ,1支病变组apoE之ε2 ,ε3和ε4等位基因频率分别为 0 .10 6 1± 0 .2 4 2 3,0 .75 76± 0 .35 6 2和 0 .136 4± 0 .2 2 6 1,2支病变组apoE之ε2 ,ε3和ε4等位基因频率分别为 0 .0 5 5 6± 0 .1992 ,0 .80 5 6± 0 .2 995和 0 .1389± 0 .2 5 6 7,3支病变组apoE之ε2 ,ε3和ε4等位基因频率分别为 0 .0 6 0 6± 0 .2 0 76 ,0 .75 76± 0 .2 82 9和 0 .1818± 0 .2 4 4 3,与正常对照组 (0 .196 1± 0 .30 13,0 .6 6 6 7±0 .36 97和 0 .1373± 0 .2 2 5 4 )比较 ,ε2明显减低 (P <0 .0 5 ) ,病变范围越大 ,ε2越低 ,但病变范围大小之间统计学无差异 ,ε3和ε4随着病变范围增大逐渐升高但统计学无显著差别 (P >0 相似文献
42.
43.
Duvillard L Florentin E Lalanne-Mistrich ML Petit JM Baillot-Rudoni S Brun-Pacaud A Brun JM Gambert P Vergès B 《Diabetologia》2005,48(7):1366-1372
Aims/hypothesis Type 1 diabetic subjects are at increased risk of cardiovascular disease and exhibit multiple qualitative abnormalities of apolipoprotein (apo) B100-containing lipoproteins. This stable isotope kinetic experiment was designed to study whether these abnormalities are associated with changes in the synthesis and fractional catabolic rates of VLDL-, IDL- and LDL-apoB100.Methods Using a bolus followed by a 16-h constant infusion of 13C-leucine, we performed a kinetic study in eight men with type 1 diabetes treated with a continuous subcutaneous insulin infusion administered by an external pump and in seven healthy men, in the fed state.Results The mean HbA1c level in the type 1 diabetic patients was 8.00±1.48%. Plasma triglyceride, and total, LDL and HDL cholesterol levels were similar in patients and control subjects. VLDL were less triglyceride rich in type 1 diabetic patients than in control subjects (VLDL triglyceride : apoB 6.91±0.81 vs 8.29±1.24 mmol/g, p=0.05). Conversely, the IDL and LDL of the type 1 diabetic patients contained relatively higher levels of triglycerides (IDL triglycerides : apoB 2.16±0.36 vs 1.57±0.30 mmol/g, p<0.01; LDL triglycerides : apoB 0.27±0.06 vs 0.16±0.04 mmol/g, p<0.05). The apoB100 pool size, production and fractional catabolic rates in the two groups of subjects were similar for all lipoprotein fractions.Conclusions/interpretation Despite qualitative abnormalities, especially abnormalities of triglyceride content, the metabolism of apoB100-containing lipoproteins is not altered in type 1 diabetic men with fair glycaemic control with continuous subcutaneous insulin infusion. The high risk of atherosclerosis in these patients cannot be explained by kinetic abnormalities of apoB100-containing lipoproteins. 相似文献
44.
《Archives of Cardiovascular Diseases》2021,114(12):828-847
Central Illustration. Pathophysiological pathways providing a causal link between high plasma concentrations of lipoprotein(a) (Lp(a)) and atherosclerotic vascular disease and aortic valve stenosis (AVS). Clinical outcomes are related to accelerated atherosclerosis complicated by atherothrombosis (myocardial infarction, stroke), peripheral artery disease (PAD) or aortic valve replacement (AVR) caused by valve calcification and aortic stenosis. Apo(a): apolipoprotein(a); LDL: low-density lipoprotein; OxPL: oxidized phospholipids; NSFA: Nouvelle Société Francophone d’Athérosclérose; SP: serine-protease domain; V: plasminogen kringle V (reproduced with permission). 相似文献
45.
观察30例冠心病、20例高脂血症患者的血脂含量、载脂蛋白C及血浆脂蛋白脂酶活性的变化,结果显示:高脂血症患者血浆脂蛋白CⅡ水平比正常人高45.72%,(P〈0.001),且与血甘油三酯值呈明显正相关(r=0.599,P〈0.001);冠心病患者血浆脂蛋白酶性显著低于正常人(P〈0.01)。提示:高脂血症患者血浆载脂蛋白CⅡ水升高可能是甘油三酯升高的重要原因,冠心病患者的血浆脂蛋白脂酶活性降低,可能 相似文献
46.
Jean-Bastien Bott Brigitte Cosquer Céline Héraud Celina Zerbinatti Christian Kelche Jean-Christophe Cassel Chantal Mathis 《Neurobiology of aging》2013
Mild cognitive impairment (MCI) is a clinical condition that often precedes Alzheimer disease (AD). Compared with apolipoprotein E-ε3 (APOE3), the apolipoprotein E-ε4 (APOE4) allele is associated with an increased risk of developing MCI and spatial navigation impairments. In MCI, the entorhinal cortex (EC), which is the main innervation source of the dentate gyrus, displays partial neuronal loss. We show that bilateral partial EC lesions lead to marked spatial memory deficits and reduced synaptic density in the dentate gyrus of APOE4 mice compared with APOE3 mice. Genotype and lesion status did not affect the performance in non-navigational tasks. Thus, partial EC lesions in APOE4 mice were sufficient to induce severe spatial memory impairments and synaptic loss in the dentate gyrus. In addition, lesioned APOE4 mice showed no evidence of reactional increase in cholinergic terminals density as opposed to APOE3 mice, suggesting that APOE4 interferes with the ability of the cholinergic system to respond to EC input loss. These findings provide a possible mechanism underlying the aggravating effect of APOE4 on the cognitive outcome of MCI patients. 相似文献
47.
M. L. Barjas-Castro M. C. P. Soares R. C. Menezes M. H. M. Carvalho F. F. Costa S. T. O. Saad 《Annals of human biology》2013,40(2):220-224
Background : The Parakanã is a group of Indians with cultural similarities to the extinct Tupi group. They are an isolated native population from East Brazilian Amazon. A number of different O alleles have been found at the blood group ABO locus in populations of several ethnic origins (Caucasians, Blacks, Amerindians). Aim : The present study describes the ABO blood group polymorphism gene of the Parakanã Indians. The Amerindian group was carefully selected for racial background. Subject and methods : The blood group polymorphism was analysed in genomic DNA from 62 Parakanã Indians. We determined the 261G deletion, the T646A and C771T mutations described in O 1variant and the G542A substitution, using PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism). Results : All Amerindians studied were homozygous for the 261G deletion. The frequencies of the T646A and C771T mutations in Parakanãs (0.65) were lower than that observed in Kayapo, Yanomama and Arara Indians (0.91) ( h 2 = 18.24; p-v < 0.001. The G542A substitution in Parakanãs was also lower (0.22) than in other tribes (0.42) ( h 2 = 9.73; p-v = 0.001). Conclusions : The different O alleles including the G542A mutation are not distributed homogeneously among all Amazonian Amerindians. Our results are in agreement with other genetic markers studied previously in Parakanã Indians, whose distinct genetic pattern differs from Europeans and even from other Amerindians. 相似文献
48.
Objectives
To evaluate the effects of interactions between ApoE genotypes, alcohol consumption and obesity on the age-related trends of blood pressure (BP) levels in postmenopausal women.Study design
A population-based prospective cohort study of all residents in Bambuì, south-eastern Brazil, aged 60 years or older. Repeated BP measurements were obtained in four waves from 851 women who underwent ApoE genotyping at baseline (88.3% of those enrolled), and multi-level random-effects pattern-mixture models were used to evaluate the age-related BP trajectories, while accounting for non-ignorable dropouts/deaths and handling heterogeneities as random parameter variations. The few measurements (2.1%) made during hormone replacement therapy were excluded from the analysis.Results
Alcohol consumption was associated with high levels of systolic and diastolic BP in an age × genotype-dependent manner only in the non-obese women (BMI < 27 kg/m2). Among those with the ?3/3 genotype, the differences in systolic and diastolic levels between drinkers and non-drinkers estimated at the age of 60 years were respectively 13.7 mmHg (p = 0.022) and 10.7 mmHg (p = 0.002), and disappeared in the older age groups, in which drinking was associated with systolic/diastolic hypertension if the non-obese women were ?4 carriers.Conclusion
In non-obese postmenopausal women, alcohol consumption is associated with systolic and diastolic hypertension early in those with the ?3/3 ApoE genotype, and late in ?4 carriers. We hypothesize the mediation of androgen hormones and the influence of ApoE genotypes on age at natural menopause. A better understanding of these mechanisms may guide better preventive choices. 相似文献49.
人重组载脂蛋白E在大肠杆菌中的表达和纯化 总被引:1,自引:0,他引:1
用含有载脂蛋白EcDNA的PET32a原核表达载体转化大肠杆菌BL21(DE3),使之高效表达载脂蛋白E-thioredoxin融合蛋白,利用融合蛋白上的一段组氨酸序列,用镍离子亲合层析柱进行分离纯化。由于在载脂蛋白E和thioredoxin之间存在凝血酶的识别位点,用凝血酶消化后,经SephacrylS-300凝胶过滤得到人重组载脂蛋白E。用此方法可以从1L大肠杆菌培养液中纯化20-30mg高纯度的各种载脂蛋白E异构体和非自然存原突变体。方法简便,产量高,纯度达95%以上。 相似文献
50.
Cultured rat hepatocytes were used to study the effects of hormones on the production of apo A-I. In addition, we compared these effects with the production of albumin. Hepatocytes were isolated from normal adult rat livers and cultured in MEM, as nearly confluent monolayers. In the absence of hormones, apo A-I and albumin accumulated in the culture medium almost linearly for periods up to 24 h. The rates of accumulation of apo A-1 and albumin in the medium were 22 ng/mg cell protein per h and 1.2 μg/mg cell protein per h, respectively. During the incubations the cellular contents of apo A-1 remained constant.
Insulin stimulated the production of albumin at concentrations over 10−10 M, but inhibited the production of apo A-I at concentrations over 10−8 M. Dexamethasone showed no significant effects on albumin production but stimulated apo A-1 production at concentrations over 10−6 M. Glucagon inhibited the production of albumin and apo A-I dose-dependently at concentrations over 10−10 M. Thus, the production of albumin and apo A-1 are presumably controlled by different regulatory mechanisms. 相似文献