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81.
目的:观察雌激素(17β-雌二醇)对氧化型低密度脂蛋白(oxLDL)诱导人脐静脉内皮细胞(HUVEC)凋亡的影响。方法 以HUVEC为对象,观察不同浓度的17β-雌二醇(1,10和100μmol/L)对oxLDL(4μg/L)诱导的凋亡的影响。结果 不同剂量的17β-雌二醇对使用oxLDL诱导的HUVEC凋亡减少70% ̄93%,其抑制呈明显的正向量效应关系,17β-雌二醇1μmol/L组细胞凋亡占  相似文献   
82.
目的探讨甘肃省某三甲医院收治的糖尿病足患者创面感染病原菌情况,分析创面感染的相关因素,为后期临床救治提供理论依据。 方法选择2017年1月至2021年12月甘肃省人民医院收治的符合入选标准的糖尿病足患者,收集并分析患者的人口信息(年龄、性别)、糖尿病足创面特征(糖尿病病程、创面持续时间、创面部位)、抗生素应用数量、实验室检测指标(红细胞计数、白细胞计数、血红蛋白、白蛋白、肌酐、胆固醇、甘油三脂、高密度脂蛋白、低密度脂蛋白、空腹血糖、糖化血红蛋白、白细胞介素-6、降钙素原)、创面细菌培养结果及药物敏感试验结果。数据比较采用χ2检验、单因素分析、多因素Logistic回归分析。 结果(1)本研究共纳入糖尿病足患者173例,其中51~60岁人数最多,有53例,占比30.6%,其次为61~70岁、41~50岁、71~80岁,分别占24.3%、20.2%、16.8%;男性总体多于女性,男性138例,占比79.8%,女性35例,占比20.2%。(2)糖尿病足患者糖尿病病程10~14年人数最多,38例,占比为22.0%,创面持续时间中人数最多为15~30 d,53例,占比为30.1%。173例患者共185个创面,其中位于足趾部位最多,有68例,占比36.8%,其次为足底52例,占比28.1%。(3)患者的实验室检测指标结果显示,红细胞计数低于正常值范围的患者占比60.1%,白细胞计数高于正常值范围的患者占比34.7%,血红蛋白低于正常值范围的患者占比42.8%,白蛋白低于正常值范围的患者占比86.1%,肌酐高于正常值范围的患者占比20.8%,胆固醇高于正常值范围的患者占比11.6%,甘油三酯高于正常值范围的患者占比23.7%,高密度脂蛋白低于正常值范围的患者占比73.4%,低密度脂蛋白高于正常值范围的患者占比12.7%,空腹血糖高于正常值范围的患者占比82.1%,糖化血红蛋白高于正常值范围的患者占比77.5%,白细胞介素-6高于正常值范围的患者占比77.5%,降钙素原高于正常值范围的患者占比68.2%。(4)173例患者共送检标本257份,其中阳性210份,阴性47份,阳性率81.7%;其中革兰阳性菌共120株,占比57.1%,革兰阴性菌共89株,占比42.4%,真菌1株,占比0.5%;革兰阳性菌中金黄色葡萄球菌65株,占比最高,为31.0%,其次是粪肠球菌16株,占比7.6%;革兰阴性菌中阴沟肠杆菌24株,占比最高,为11.4%,其次是大肠埃希菌21株,占比10.0%;药物敏感试验结果显示,金黄色葡萄球菌对甲氧苄啶/磺胺甲恶唑、万古霉素、利奈唑胺等抗生素较为敏感,敏感率均为100.0%;其对青霉素耐药率高,耐药率为89.2%,其次为克林霉素和红霉素,耐药率分别为78.5%、76.9%;阴沟肠杆菌对美洛培南、厄他培南、头孢哌酮/舒巴坦、左旋氧氟沙星等较为敏感,敏感率均为100.0%,其次为阿米卡星、亚胺培南、头孢吡肟,敏感率均为95.8%;大肠埃希菌对美洛培南、厄他培南、亚胺培南、替加环素、头孢西丁、阿米卡星等较为敏感,敏感率均为100.0%。173例患者中,抗生素应用数量为0的有19例,占比11.0%;1种及2种的均有61例,占比均为35.3%;3种的有25例,占比14.4%;4种以上7例,占比4.0%。(5)对糖尿病足患者感染的17个相关因素进行单因素分析,结果显示,创面持续时间、抗生素应用数量、白细胞计数、血红蛋白、白蛋白、高密度脂蛋白、肌酐、糖化血红蛋白、白细胞介素-6、降钙素原等相关因素差异均有统计学意义(P<0.05);进一步行多因素Logistic回归分析结果显示,与创面感染相关的因素有创面持续时间、抗生素应用数量,高密度脂蛋白(OR=1.530、1.923、2.587,P<0.05)。 结论糖尿病足患者创面病原菌培养中,革兰阳性菌中以金黄色葡萄球菌、粪肠球菌为主,而革兰阴性菌以阴沟肠杆菌、大肠埃希菌为主;糖尿病足患者感染的独立危险因素为创面形成时间长、抗生素滥用,高密度脂蛋白低。  相似文献   
83.
  1. 15-Lipoxygenase (15-LO) has been implicated in the pathogenesis of atherosclerosis because of its localization in lesions and the many biological activities exhibited by its products. To provide further evidence for a role of 15-LO, the effects of PD 146176 on the development of atherosclerosis in cholesterol-fed rabbits were assessed. This novel drug is a specific inhibitor of the enzyme in vitro and lacks significant non specific antioxidant properties.
  2. PD 146176 inhibited rabbit reticulocyte 15-LO through a mixed noncompetitive mode with a Ki of 197 nM. The drug had minimal effects on either copper or 2,2′-azobis(2-amidinopropane)hydrochloride (ABAP) induced oxidation of LDL except at concentrations 2 orders higher than the Ki.
  3. Control New Zealand rabbits were fed a high-fat diet containing 0.25% wt./wt. cholesterol; treated animals received inhibitor in this diet (175 mg kg−1, b.i.d.). Plasma concentrations of inhibitor were similar to the estimated Ki (197 nM). During the 12 week study, there were no significant differences in weight gain, haematocrit, plasma total cholesterol concentrations, or distribution of lipoprotein cholesterol.
  4. The drug plasma concentrations achieved in vivo did not inhibit low-density lipoprotein (LDL) oxidation in vitro. Furthermore, LDL isolated from PD 146176-treated animals was as susceptible as that from controls to oxidation ex vivo by either copper or ABAP.
  5. PD 146176 was very effective in suppressing atherogenesis, especially in the aortic arch where lesion coverage diminished from 15±4 to 0% (P<0.02); esterified cholesterol content was reduced from 2.1±0.7 to 0 μg mg−1 (P<0.02) in this region. Immunostainable lipid-laden macrophages present in aortic intima of control animals were totally absent in the drug-treated group.
  6. Results of these studies are consistent with a role for 15-LO in atherogenesis.
  相似文献   
84.
吸烟与动脉硬化性脑梗塞关系的研究   总被引:15,自引:1,他引:14  
目的:探讨吸烟与动脉硬化性脑硬塞(ASCI)的关系。方法:对102例ASCI患者及108例正常人血清载脂蛋白(Apo-B)、高密度脂蛋白胆固醇(HDL-C)、总胆固醇(TC)进行测定及对比分析。结果:ASCI组Apo-B比对照组显著升高(P<0.01),HDL-C比对照组显著降低(P<0.01),而TC两组间无明显差异(P>0.05)。在对照组及AS-CI组吸烟者Apo-B均高于非吸烟者(P<0.01,P<0.05),而HDL-C吸烟者明显低于非吸烟者(P<0.01)。结论:吸烟能促使血清Apo-B增高及HDL-C下降,可以认为吸烟是ASCI的危险因素之一。  相似文献   
85.
Summary In order to investigate the effect of a short-term application of marine n-3 polyunsaturated fatty acids on the composition of serum very low density lipoproteins (VLDL), low density lipoproteins (LDL), and high density lipoproteins (HDL), nine women aged 29±4.2 years, following a diet with a SFA/MUFA/PUFA profile of 2.4/3/1, received supplements of six capsules daily, each capsule containing 0.137 g of n-3 fatty acids (14.5% eicosapentaenoic acid (EPA) and 8.9% docosahexaenoic acid (DHA)) for 10 d. Food consumption, assessed during two 10-days periods indicates that percentage contribution of SFA, MUFA, and PUFA to the daily energy intake did not change through the fish-oil supplementation period, but the daily consumption of n-3 fatty acids increased 2.3 times. N-3 fatty supplementation increased EPA and DHA percentages in serum phospholipids, but failed to decrease (p>0.05) the cholesterol and triglyceride concentration in serum LDL and HDL, although it did so in VLDL. In contrast, the lipoprotein-phospholipid and lipoprotein-protein concentrations were markedly affected, mainly in LDL and HDL (at least p<0.01). HDL and VLDL compositions were not affected but the total mass (lipid+protein in mg/dl) concentration of these lipoproteins significantly decreased (p<0.05), suggesting a lower number of these particles in circulating blood after the n-3 treatment. The LDL-cholesterol/LDL-apolipoprotein B ratio increased (p<0.01) reflecting a probable increase in LDL size. Following fish oil supplementation, LDL particles contained a significantly lower amount of phospholipids, which also suggests changes in the surface/core ratio of the average LDL. Changes in serum lipoprotein lipids did not significantly correlate with any dietary change other than the n-3 fatty acid increase. The results indicate that a 10-day application of a small supplement of n-3 change the LDL composition leading to less atherogenic LDL particles with lower phospholipid and apolipoprotein (Apo) B concentrations. Received: 15 May 1998, Accepted: 28 August 1998  相似文献   
86.
This study was carried out to investigate the relationship between lipoprotein (a) levels and the development of atherosclerosis in chronic renal failure (CRF) patients with the possible role of the liver. Serum Lp (a) levels were measured in samples from 20 CRF patients on hemodialysis (HD), 20 liver cirrhosis (LC) patients, 20 patients having both CRF and LC and undergoing HD, and 20 normal control subjects. Renal function (blood urea nitrogen (BUN) and creatinine), hepatic function (transaminases (ALT and AST), alkaline phosphatase (ALP) and total bilirubin) investigations and serum cholesterol were carried out for all the subjects enrolled in this study. Serum Lp (a) concentration in CRF patients without LC was 87.25 +/- 6.17 mg/dl, which was significantly higher than all the investigated groups (P < 0.001). Lp (a) concentration in patients with both CRF and LC was 24.65 +/- 1.98 mg/dl, which was not significantly different from the controls, but was significantly higher than that in the subjects with LC only (P < 0.001) where the latter group had significantly low Lp (a) values (11.1 +/- 0.99) relative to all the other groups (P < 0.001). Lp (a) correlated positively with cholesterol in all groups except the LC subjects, but did not correlate with age, or renal function in both CRF groups.  相似文献   
87.
目的:研究新疆哈萨克族、汉族间血脂水平的差异及与血压等有关影响因素间的关系。方法:抽样调查新疆阿勒泰地区城市居民哈、汉两民族214 人的血脂、血压水平及其他有关因素,采用逐步回归分析方法,分析其相关关系,结果:哈萨克族血清总胆固醇( T C)和低密度脂蛋白( L D L)高于汉族( P< 0.01),哈萨克族高血压组 T C高于汉族高血压组( P< 0.01),哈萨克族高血压组 L D L高于哈萨克族正常血压及汉族高血压组和正常血压组( P< 0.05~0.01),哈萨克族正常血压组 L D L 高于汉族高血压组( P< 0.01)。多元逐步回归分析提示: W H R(腰围/臀围)是影响 T G(甘油三脂)、 L D L及 H D L(高密度脂蛋白)的主要因素,它与前两者呈正相关而与后者呈负相关。结论:新疆阿勒泰地区哈、汉两民族间血脂水平存在着差异, W H R肿血脂水平有一定的影响。  相似文献   
88.
目的:分析2型糖尿病患者非酶促糖化低密度脂蛋白形成与血糖和血脂的关系,以及对胆固醇代谢的影响。方法:随机选择52例2型糖尿病患者和17例非糖尿病患者对照,测定其空腹血中血糖、血清甘油三酯、总胆固醇、低密度脂蛋白胆固醇、β脂蛋白浓度以及糖化低密度脂蛋白指数。结果:糖化低密度脂蛋白指数与血糖、血清甘油三酯、β脂蛋白、总胆固醇以及低密度脂蛋白胆固醇均呈线性正相关,其相关系数分别为r=0.870(P<0.05),r=0.938(P<0.05),r=0.92(P<0.01),r=0.993(P<0.05)和r=0.999(P<0.0005)。结论:高血糖和高甘油三酯血症可促使低密度脂蛋白高糖化形成,进而可干扰胆固醇代谢,导致低密度脂蛋白胆固醇以及总胆固醇浓度升高。  相似文献   
89.
为研究高胆固醇膳食诱发兔胆囊胆固醇结石模型的脂代谢变化,以及高密度脂蛋白(HDL)对其脂代谢及成石的影响,将动物随机分为对照组、高胆固醇膳食组及高胆固醇膳食+HDL注射组,观察各组血浆脂质、胆汁中胆固醇、血卵磷脂胆固醇酰基转移酶(LCAT)活性及血和胆汁中胆汁酸及成石率的变化。结果显示:动物体内胆固醇等脂质的消除障碍导致体内脂质的大量堆积以及清除紊乱,是高胆固醇膳食诱发兔胆囊结石脂代谢变化的主要特点,胆汁中胆固醇与胆汁酸的清除比例失调可能导致成石性胆汁形成;尽管外源性HDL制剂能够升高血浆HDL2-C/HDL3-C的比值,增加LCAT的活性从而促使HDL成熟,并能降低肝脏的胆固醇含量,但未能降低成石率。结果表明外源性HDL制剂对兔胆囊结石形成中脂代谢有一定的影响,但抗成石作用不明显  相似文献   
90.
Effect of metabolic acidosis on hyperlipidemia in uremia   总被引:2,自引:0,他引:2  
Nine patients (aged 18±1 years) on maintenance hemodialysis with metabolic acidosis and hyperlipidemia were studied before and after 2 weeks of oral sodium bicarbonate (NaHCO3) treatment to correct the acidosis. To control for the effect of additional sodium, they were also studied after 2 weeks of an equivalent amount of oral sodium chloride (NaCl). Oral NaHCO3 treatment led to significant increases in venous pH, serum bicarbonate, and serum 1,25-dihydroxyvitamin D3 concentrations, but no significant change in total and ionized calcium, phosphate, sodium, potassium, creatinine, blood urea nitrogen, and intact parathyroid hormone concentrations. Oral NaCl did not change any of the biochemical parameters. Before treatment of acidosis, these uremic patients had high serum triglycerides, low serum high-density lipoprotein (HDL) cholesterol, but normal total cholesterol compared with controls. Following 2 weeks of NaHCO3 treatment, there was a significant decrease in the serum concentrations of triglycerides (P<0.01). HDL and total cholesterol did not change. There were no changes in triglycerides, HDL or total cholesterol from baseline values following 2 weeks of NaCl. Thus treatment of metabolic acidosis ameliorated hypertriglyceridemia but had no effect on HDL and total cholesterol in patients with uremia on hemodialysis. The underlying mechanism may involve 1,25-dihydroxyvitamin D3. Received: 3 August 1998 / Revised: 30 November 1998 / Accepted: 2 December 1998  相似文献   
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