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71.
Summary The study was designed to investigate the antimanic profile of carbamazepine as a first-line drug in affective or schizoaffective disorders, to correlate the clinical efficacy with the plasma level of carbamazepine and its 10,11-epoxide metabolite, and to test the potential value of monitoring the salivary level. It was administered alone for 3 weeks to 21 acute manic inpatients. During the first week, the dosage was rapidly increased to 800 mg/day in order to produce steady-state plasma levels of carbamazepine on Day 7. The individual dose was then adjusted to maintain the therapeutic range of 8–12 mg/l. Plasma and saliva levels of the drug and its metabolite, as well as clinical status were assessed weekly.Overall, there was 62% globally improved patients and 77% in affective disorders. The improvement of manic symptoms was significantly lower in schizoaffective than in affective disorders, whereas the dropout rate and the need for antipsychotic medication was higher in the former group.The antimanic response was significantly correlated with the plasma levels both of carbamazepine and its epoxide metabolite, with a time-lag consistent with a delayed drug effect.Drug and metabolite concentrations in saliva were close to their plasma free fraction and were strongly correlated with their plasma levels, suggesting the potential value of salivary drug monitoring.  相似文献   
72.
There is evidence that onions and garlic protect against cancer in humans. It has been suggested that this effect is partly due to the organosulfur compounds in Allium vegetables and that these substances act through induction of phase II detoxification enzymes. Here, we hypothesized that alk(en)yl thiosulfates, sodium n-propyl thiosulfate (NPTS), and sodium 2-propenyl thiosulfate (2PTS), which were identified in onions and garlic, respectively, may induce phase II enzymes. Therefore, rat hepatoma cells (H4IIE) were cultured with 1 to 100 μmol/L of NPTS or 2PTS for 48 hours at 37°C; and the activities and messenger RNA (mRNA) expression levels of phase II enzymes in H4IIE cells were investigated. The effects of diallyl trisulfide and tert-butylhydroquinone, known as phase II inducers, were also examined as positive controls and compared with the responses of NPTS and 2PTS. Quinone reductase (QR) activity and mRNA expression levels of QR and epoxide hydrolase 1 were significantly increased by 2PTS (P < .05-.005). In particular, QR activity was increased at a relatively low concentration of 2PTS (10 μmol/L). However, glutathione S-transferase activity and mRNA expression levels of glutathione S-transferase A5 and uridine diphosphate glucuronosyl transferase 1A1 were not changed by 2PTS. In contrast, NPTS did not affect the activities and mRNA expression levels of these phase II enzymes. These results show that 2PTS can induce phase II enzymes, and its inductive effect is comparable or superior to that of diallyl trisulfide and tert-butylhydroquinone.  相似文献   
73.
目的探讨维生素K环氧化物还原酶复合物1基因(VKORC1)-1639G/A多态性对中国汉族人华法林应用剂量的影响。方法应用PCR—RFLP法检测129例长期口服华法林的患者和198例健康对照者VKORC1-1639G/A多态性,比较VKORC1不同基因型间平均华法林剂量。结果病例组VKORC1-1639AA、AG、GG基因型频率分别为74.4%(96/129)、23.3%(30/129)、2.3%(3/129),等位基因A和G频率分别为86%和14%。病例组与健康对照者VKORC1-1639G/A多态性分布差异无统计学意义(P〉0.05)。VKORC1-1639不同基因型患者所需华法林平均剂量差异有显著统计学意义(P〈0.(301),AA型剂量[(1.444±0.282)mg/INR]显著低于AG型[(1.629±0.258)mg/INR,P=0.002]和GG型患者[(2.031±0.087)mg/INR,P=0.017]。结论中国人华法林应用剂量偏低可能与VKORC1-1639AA型占多数有关。  相似文献   
74.
目的研究不同浓度可溶性环氧化物水解酶抑制剂(soluble epoxide hydrolase inhibitor,s EHi)AUDA对颈动脉狭窄(carotid stenosis,CS)患者外周血来源的晚期内皮祖细胞(late endothelial progenitor cell,late EPC)的影响。方法入选研究对象60例,分成颈动脉狭窄组(n=35)和对照组(n=25)。密度梯度离心法,从外周血获取单个核细胞培养至21 d后鉴定内皮祖细胞;以不同浓度AUDA(0,0.1,1,10μmol/L)和晚期EPC共培养24 h,分别采用MTT法,黏附能力测定实验和Transwell小室来观察其增殖,黏附,迁移能力。同时采用Western blot法观察AUDA处理后其VEGF的表达。结果体外培养21 d时,细胞呈典型长梭形,21 d时,呈铺路石样,并可摄取FITCUEA-I和Dil-ac LDL。与对照组相比,CS患者late EPC的增殖,黏附和迁移能力均显著下降(P0.05);与处理前(0umol/L)相比,AUDA呈剂量依赖性地增强CS患者late EPC增殖,黏附和迁移能力并促进CS患者late EPC表达VEGF。结论 s EHi具有促进late EPC增殖,黏附和迁移等功能的作用,其有望成为一类治疗CS的新型药物。  相似文献   
75.
目的应用荧光PCR-熔解曲线法检测新疆回族人群细胞色素P450酶2C9(CYP2C9)和维生素K环氧化物还原酶复合体亚单位1(VKORC1)基因多态性,研究新疆回族人群CYP2C9和VKORC1基因分布及基因突变频率情况,并评价荧光PCR-熔解曲线法临床使用的适用性。方法采用荧光PCR-熔解曲线法和测序法对比检测CYP2C9*2、CYP2C9*3和VKORC1(-1639G/A)的基因多态性。结果 228例新疆回族人群中,共检测出CYP2C9*1/*1标本199例,CYP2C9*1/*2标本2例,CYP2C9*1/*3标本26例,CYP2C9*3/*3标本1例,未检测出CYP2C9*2/*2和CYP2C9*2/*3标本。VKORC1(-1639G/A)检测出2种等位基因G和A,其中VKORC1-1639G/G型标本检出2例,VKORC1-1639G/A型标本检出39例,VKORC1-1639A/A型标本检出187例,与测序法对比检测比较,荧光PCR-熔解曲线法与测序法检测结果完全一致。结论新疆回族人群同样具有CYP2C9基因*2、*3位点和VKORC1基因-1639位点的多态性,其发生频率与新疆维吾尔族及其他地域人群的具有一定差异,所采用的荧光PCR-熔解曲线法用于基因多态性检测可满足临床检测要求。  相似文献   
76.
Soluble epoxide hydrolase (sEH) is an enzyme responsible for the conversion of lipid epoxides to diols by the addition of water. Biological actions on the cardiovascular system that are attributed to epoxides include vasodilation, antiinflammatory actions and vascular smooth muscle cell antimigratory actions. Conversion of arachidonic acid epoxides to diols by sEH diminishes the beneficial cardiovascular properties of these epoxyeicosano‐ids. Cardiovascular diseases in animal models and humans have been associated with decreased epoxygenase activity or increased sEH activity and these changes are responsible for the progression of the disease state. More recently, sEH gene polymorphisms in the human population have been associated with increased risk for cardiovascular diseases. Thus the biological actions of epoxyeicosanoids and the sEH enzyme are ideal therapeutic targets for cardiovascular diseases. The rapid development of 1,3‐disubstituted urea based sEH inhibitors over the past five years has resulted in a number of studies demonstrating cardiovascular protection. sEH inhibitors have antihypertensive and antiinflammatory actions and have been demonstrated to decrease cerebral ischemic and renal injury in rat models of hypertension. These findings of beneficial actions in animal models of disease position the sEH enzyme as a promising therapeutic target for cardiovascular diseases.  相似文献   
77.
1. The antidiabetic agents, thiazolidinediones (TZD), ligands for peroxisome proliferator-activated receptor-γ (PPARγ), have been reported to reduce cardiac hypertrophy. However, the underlying mechanism is still elusive. 2. We previously reported that soluble epoxide hydrolase (sEH) was specifically upregulated by angiotensin-II (AngII), which directly mediated AngII-induced cardiac hypertrophy. In the present study, we examined the role of sEH in PPARγ inhibiting AngII-induced cardiac hypertrophy. 3. The protein level of sEH was elevated in the left ventricle of AngII-infused Sprague-Dawley rats. Administration of the TZD rosiglitazone decreased this induction. In vitro, AngII upregulated the expression of sEH and hypertrophy markers, including atrial natriuretic factor and β-myosin heavy chain, in rat neonatal cardiomyocytes and H9c2 cells, which was attenuated by rosiglitazone and pioglitazone. An elevated level of sEH was also found in the left ventricle of heterozygous PPARγ-deficient mice. The effect of TZD on sEH level could be reversed by treatment with the PPARγ antagonists, GW9662 and BADGE, which suggests PPARγ activation. In elucidating the mechanisms by which PPARγ inhibited AngII-induced sEH expression, we found that rosiglitazone inhibited AngII-induced sEH promoter activity in H9c2 cells. In contrast, the activity of the human sEH 3'UTR was not affected by AngII and TZD. 4. Our results suggest that the protective role of PPARγ activation in AngII-induced cardiac hypertrophy is, at least in part, through downregulating sEH.  相似文献   
78.
This study elucidates the association of acrylamide metabolites, N-acetyl-S-(2-carbamoylethyl)-cysteine (AAMA), N-acetyl-S-(1-carbamoyl-2-hydroxyethyl)-cysteine (GAMA2), and N-acetyl-S-(2-carbamoyl-2-hydroxyethyl)-cysteine (GAMA3) in urine with genetic polymorphisms of the metabolic enzymes cytochrome P450 2E1 (CYP2E1), microsomal epoxide hydrolase (mEH) in exon 3 and exon 4, glutathione transferase theta (GSTT1) and mu (GSTM1), involved in the activation and detoxification of acrylamide (AA) in humans. Eighty-five workers were recruited, including 51 AA-exposed workers and 34 administrative staffs serve as controls. Personal air sampling was performed for the exposed workers. Each subject provided pre- and post-shift urine samples and blood samples. Urinary AAMA, GAMA2 and GAMA3 levels were simultaneously quantified using liquid chromatography-electronspray ionization/tandem mass spectrometry (LC-ESI-MS/MS). CYP2E1, mEH (in exon 3 and exon 4), GSTT1, and GSTM1 were analyzed using polymerase chain reaction (PCR). Our results reveal that AA personal exposures ranged from 4.37 × 10−3 to 113.61 μg/m3 with a mean at 15.36 μg/m3. The AAMA, GAMA2, and GAMA3 levels in the exposed group significantly exceeded those in controls. The GAMAs (the sum of GAMA2 and GAMA3)/AAMA ratios, potentially reflecting the proportion of AA metabolized to glycidamide (GA), varied from 0.003 to 0.456, and indicate high inter-individual variability in the metabolism of AA to GA in this study population. Multivariate regression analysis demonstrates that GSTM1 genotypes significantly modify the excretion of urinary AAMA and the GAMAs/AAMA ratio, exon 4 of mEH was significantly associated with the urinary GAMAs levels after adjustment for AA exposures. These results suggest that mEH and/or GSTM1 may be associated with the formation of urinary AAMA and GAMAs. Further study may be needed to shed light on the role of both enzymes in AA metabolism.  相似文献   
79.
目的:构建杜氏盐藻S腺苷高半胱氨酸水解酶(SAHH)的酵母双杂交诱饵载体pGBKT7-SAHH,并检测其对酵母细胞的毒性和自激活作用。方法:应用RT-PCR扩增杜氏盐藻的SAHHcDNA,测序分析后与酵母双杂交诱饵载体pGBKT7连接,构建诱饵载体pGBKT7-SAHH。用PEG/LiAc法将诱饵载体转入AH109和Y187酵母中,通过表型筛选检测诱饵蛋白对酵母有无毒性和自激活作用。结果:成功构建了诱饵载体pGBKT7-SAHH并成功转化到酵母细胞AH109和Y187中,表达的融合蛋白对宿主酵母细胞无毒性。在AH109和Y187酵母细胞中诱饵载体均未激活报告基因HIS3和ADE2,但是激活了报告基因MEL1。结论:诱饵载体pGBKT7-SAHH可用酵母双杂交方法筛选与SAHH相互作用的蛋白。  相似文献   
80.
A significant number of human clinical trials have reported no adverse effects associated with consumption of Lactobacillus reuteri (L. reuteri). In the present study, the clinical safety and toxicology of oral ingestion of supplement capsules containing L. reuteri NCIMB 30242 was investigated. A randomized group of 131 subjects received a dose of 2.9 × 109 CFU L. reuteri NCIMB 30242 capsules (n = 67) or placebo capsules (n = 64) twice daily for 9 weeks. Clinical chemistry and hematological parameters of safety were analyzed. The frequency, duration and intensity of adverse events (AE)s and clinical significance of safety parameters were recorded for both groups. No clinically significant differences between the probiotic capsule and placebo capsule treated groups were detected in either the blood clinical chemistry or hematology results. The frequency and intensity of AEs was similar in the two groups. These results demonstrate that administration of a twice daily dose of 2.9 × 109 CFU was safe and well tolerated in the population evaluated over 9 weeks.  相似文献   
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