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61.
目的 探讨上海大学生非酒精性脂肪肝(NAFLD)的患病率及与载脂蛋白E(ApoE)基因多态性的相关性.方法 对上海同济大学4 148名在校学生进行问卷调查;采用肝脏超声以及血肝功能、脂蛋白等生化指标检测,将确诊的NAFLD患者与正常者200例,进行外周血PCR-RFLP检测ApoE基因多态性.结果 (1)4 148名大学生中NAFLD检出398例(9.6%),NAFLD患者的体重指数、腰臀比、甘油三酯、总胆固醇、丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、谷氨酰转移酶均高于对照组(P<0.01),且随NAFLD程度加重,有递增趋势.(2)NAFLD组和对照组ApoE基因型分布比较差异显著(,P<0.01).NAFLD E4/4基因型分布频率(5.5%)明显升高,E3/3分布频率(61.8%)明显减低(均P<0.01).(3)非条件logistic回归分析显示总胆固醇、低密度脂蛋白胆固醇、腰臀比、AST、ALT、GGT与E4/4基因型密切相关.结论 ApoE基因112位和158位的氨基酸残基发生相应的变化可引起不同程度的脂质代谢障碍,E4/4可能是导致NAFLD发生的遗传因素之一.  相似文献   
62.
目的:观察载脂蛋白E基因敲除(Apo E-/-)小鼠动脉粥样硬化斑块形成过程中血管平滑肌细胞瞬时受体电位通道5(TRPC5)蛋白的表达变化,以及阿托伐他汀药物干预对TRPC5的影响并探讨其作用机制。方法:将40只6周龄雄性Apo E-/-小鼠随机分为模型组和他汀干预组,高脂饲料喂养建立动脉粥样硬化模型。他汀干预组给予阿托伐他汀(20 mg·kg-1·d-1)灌胃,模型组给予等量生理盐水灌胃。20只同龄雄性野生型C57BL/6J小鼠给予普通饲料喂养作为正常对照组。各组小鼠分别喂养至20和30周龄,分别取10只取血并处死。取主动脉根部做石蜡切片行HE染色形态学观察,测量并计算斑块相对面积;免疫组织化学染色检测各组小鼠TRPC5蛋白表达变化。取胸腹段主动脉行实时荧光定量PCR,检测主动脉中TRPC5通道蛋白mRNA的表达水平。结果:与模型组相比,阿托伐他汀干预组的血脂明显下降,斑块总面积明显减小,TRPC5蛋白水平及mRNA含量明显下降;30周龄模型组的TRPC5蛋白表达稍高于20周龄模型组,但差异无统计学意义;30周干预组较20周干预组相比,TRPC5水平有降低趋势且差异有统计学意义。结论:阿托伐他汀可能通过下调TRPC5蛋白表达从而延缓动脉粥样硬化进程。  相似文献   
63.
More than two-thirds of American adults are overweight or obese, with many attempting to lose weight to avoid adverse health outcomes and improve well-being. Achieving long-term weight loss (LTWL) success, defined as reaching at least a 5% to 10% weight loss goal, is challenging, yet important for overall metabolic health. It is currently unclear whether achieving higher thresholds of LTWL is associated with improved health. Therefore, the purpose of this study was to examine the association between LTWL thresholds (5%-9.9%, 10%-14.9%, 15%-19.9%, ≥20%) and metabolic health (metabolic syndrome and metabolic risk z score) among 7670 US adult respondents to the National Health and Nutrition Examination Survey (2007-2014) who were overweight or obese (past or present), were not underweight in the past year, not pregnant, and attempting to lose or maintain weight. A subsample of 3362 participants was used in the analysis of the metabolic risk z score. Multivariable regression models were constructed adjusting for covariates. Results indicate that the lowest and the 2 highest LTWL thresholds were related to lower odds for metabolic syndrome; for example, greater than or equal to 20% LTWL (odds ratio=0.52; 95% CI, 0.23-0.44; P<.001). All LTWL thresholds were significantly associated with the metabolic risk z score, with the largest effect among the 2 highest LTWL thresholds, that is, 15% to 19.9% LTWL (β=?0.45; 95% CI, ?0.54 to ?0.36; P<.001) and greater than or equal to 20% LTWL (β=?0.35; 95% CI, ?0.53 to ?0.17; P<.001). In conclusion, although achieving the currently recommended LTWL target was related to improved metabolic health, the 15% LTWL threshold was associated with more favorable outcomes.  相似文献   
64.
Background: Glaucoma is characterized by optic neuropathy of the retinal ganglion cell. It may be possible that β-amyloid (Aβ) and apolipoprotein E (APOE), the main proteins of the pathogenesis of AD, play a role in glaucoma development. The aim of this study was to evaluate a relationship between the APP and APOE gene polymorphisms and the risk of primary open-angle glaucoma (POAG) occurrence.

Materials and methods: The study consisted of 183 patients with POAG and 209 healthy subjects. Genomic DNA was extracted from peripheral blood. Analysis of the gene polymorphisms was performed using PCR-RFLP.

Results: We found a statistically significant increase of the -491?T allele frequency (p?=?0.02; OR?=?1.48; 95% CI?=?1.06–2.08) of APOE in POAG compared to healthy controls. There were no differences in the genotype and allele distributions and odds ratios of the APP polymorphism between patients and controls group. We also found an association between APOE polymorphic variant and retinal nerve fiber layer (RNFL). There was a statistically significant difference in the APOE gene A/T genotype frequency in the early POAG stage and middle-advanced POAG stage in comparison to the advanced POAG stage (p?=?0.04; OR?=?3.38; 95% CI?=?1.04–10.97).

Conclusions: The -491?T allele of APOE polymorphism may be associated with a risk of POAG occurrence in the Polish population.  相似文献   
65.
66.
We have previously demonstrated alterations in apolipoprotein B-48 metabolism in the post-prandial state in patients with non-insulin-dependent diabetes mellitus. This study investigates the relationship between hypertriglyceridaemia and post-prandial lipoprotein metabolism. Four groups of patients were examined: non-insulin-dependent diabetic patients, with normal serum triglyceride levels (serum triglyceride <2.1 mmol l−1; haemoglobin HbA1c 5.5%±0.4%); poorly controlled, non-insulin-dependent diabetic patients with hypertriglyceridaemia (serum triglyceride >2.1 mmol 1−1; HbA1c 8.8%±0.9%); nondiabetic subjects with serum triglycerides <2.1 mmoll−1; and non-diabetic subjects with hypertriglyceridaemia (serum triglyceride>2.1 mmol l−1). Subjects were studied fasting and following a high-fat meal (1300 kcal). The triglyceride-rich lipoprotein fraction was isolated by ultracentrifugation (d<1.006 g ml−1). Apoprotein B-48, apoprotein B-100 and apoprotein E were separated on 4%–15% gradient gels and quantified as a percentage of the fasting concentration by densitometric scanning. Triglyceride-rich lipoprotein apolipoprotein B-48 and apolipoprotein B-100 post-prandial profiles demonstrated a maximum increase either at 2 h or rising still further to a peak at 6 h before falling in the diabetic groups and hypertriglyceridaemic non-diabetic subjects when compared with the normotriglyceridaemic control subjects whose levels decreased after 2 h (P<0.05). A significantly different triglyceride-rich lipoprotein apolipoprotein E profile was also exhibited by the diabetic patients (P<0.05). Levels of triglyceride-rich lipoprotein, cholesterol, triglyceride, total protein and apoprotein B were elevated in the hypertriglyceridaemic subjects, both diabetic and non-diabetic. These results indicate that hypertriglyceridaemia is associated with altered metabolism and composition of post-prandial triglyceride-rich lipoprotein particles in both poorly controlled diabetic and non-diabetic subjects.  相似文献   
67.
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   
68.
树鼩HDL_3和HDL_2共占血浆总脂蛋白的90%以上,是转运血浆胆固醇的主要脂蛋白,其HDL_2中载脂蛋白构成独特,琼脂糖电泳显示为β脂蛋白,可能在转运脂质中起特殊作用。喂高胆固醇饲料后,血浆HDL_3及HDL_2浓度明显增加,HDL_2中的apo E比例也显著增加,高酪蛋白饲料则能抑制高胆固醇对HDL的作用,并使HDL_3中出现一新的MW22.4kD蛋白成分。这些改变有利于HDL加快转运胆固醇至肝脏分解代谢。  相似文献   
69.
本文对60例糖尿病患者及62例正常人的血清载脂蛋白(Apo)-Al,Apo-B高密度脂蛋白(HDL)和低密度脂蛋白(LDL)水平进行了测定,结果显示:(1)糖尿病患者Apo-Al水平和Apo-B水平均明显高于正常人(P<0.01)。(2)住院治疗前,糖尿病患者血清HDL水平明显低于正常人(P<0.01)。(3)住院治疗期间糖尿病患者血清HDL水平显著增高(P<0.01),而LDL水平无明显改变(P>0.05)。  相似文献   
70.
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   
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