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101.
目的:采用腹腔注射链脲佐菌素 切除双侧卵巢复合方法建立绝经后糖尿病骨质疏松大鼠模型,观察糖尿病骨质疏松大鼠破骨细胞的改变。方法:实验于2003-12/2004-08在河北医科大学第三医院中心实验室完成。①实验材料:选用2.5~3个月龄清洁级雌性Wistar大鼠60只。②实验分组:完全随机设计分为6组:正常对照组、正常假手术组及正常双侧卵巢切除组均为8只;糖尿病对照组、糖尿病假手术组及糖尿病双侧卵巢切除组均为12只。③实验干预:采用链脲佐菌素诱导制备糖尿病大鼠模型1周后,将大鼠麻醉结扎输卵管切除卵巢。假手术组大鼠不作卵巢切除,余操作同去卵巢组。卵巢切除后0,2,4,8周随机选择各组大鼠1只,收集骨髓,进行体外骨髓破骨细胞样细胞的培养。④实验评估:切除双侧卵巢后2,4,8周时测量各组大鼠体质量、血糖;细胞培养7d后,进行细胞固定和抗酒石酸酸性磷酸酶染色(抗酒石酸酸性磷酸酶染色阳性且细胞核≥3个的细胞认定为破骨细胞样细胞);倒置显微镜计数破骨细胞样细胞数量。结果:制成糖尿病模型及切除卵巢后,3组糖尿病大鼠死亡7只,进入结果分析53只。①各组大鼠血糖和体质量的变化:切除卵巢0,2,4,8周,3组糖尿病大鼠血糖均高于正常组(P<0.01),体质量均低于正常组(P<0.01);4周时,正常双侧卵巢切除组体质量高于同期正常对照组和正常假手术组;糖尿病双侧卵巢切除组体质量在2,4,8周时均高于同期糖尿病对照组和糖尿病假手术组(4周P<0.05,8周P<0.01)。②切除卵巢后各组大鼠体外培养的破骨细胞样细胞形成的变化:糖尿病双侧卵巢切除大鼠破骨细胞多于糖尿病大鼠及正常去卵巢大鼠,且破骨细胞数量随着去卵巢的时间和糖尿病病程延长而增加。③骨髓来源的体外破骨细胞样细胞的形成与血糖、糖尿病病程及去卵巢时间的相关性分析:破骨细胞数量与糖尿病病程呈正相关,而与血糖增高的程度无关(r=-0.537;P=0.109)。结论:①卵巢切除对大鼠的血糖无显著影响,对大鼠体质量的影响被糖尿病减弱,在糖尿病早期破骨细胞样细胞的形成已有增加。②破骨细胞形成增加可能是绝经后糖尿病骨质疏松的原因之一。  相似文献   
102.
目的:观察差速贴壁技术对星形胶质细胞纯化率的影响,旨在建立一套可靠的大鼠脑皮质星形胶质细胞的取材分离、纯化培养技术。方法:实验于2006-06/08在泰山医学院生命科学研究所完成。实验材料:出生2~3d的Wistar大鼠,雌雄不拘,由泰山医学院生命科学研究所实验动物中心提供。实验方法:选用出生二三天的Wistar大鼠进行脑皮质星形胶质细胞原代培养。实验分两组培养:常规培养组和差速贴壁培养组。差速贴壁培养组分别于15,30min取出,轻轻翻转培养瓶,将上清液移至另一培养瓶中,放入培养箱中继续培养。7~10d后传代,待细胞分层生长后,置于37℃摇床中250r/min振荡18h,倒掉上清液,D-Hank’s液洗3次后,加入0.25%胰酶消化,倒置显微镜下观察,待细胞突起回缩后加入含血清的培养基终止消化,用吸管反复吹打使细胞从瓶壁上脱落,细胞悬液1000r/min离心5min后,弃上清液,加入含体积分数为0.2血清的DMEM培养基混悬沉淀,接种入预先涂有L-多聚赖氨酸的培养瓶中继续培养。采用双重免疫荧光法鉴定星形胶质细胞纯度,测定积分吸光度值判断星形胶质细胞的生长状况。结果:①应用差速贴壁技术培养星形胶质细胞可明显提高星形胶质细胞纯度[常规培养组:(82±3)%,差速贴壁培养组15min:(94±2)%,差速贴壁培养组30min:(95±2)%,P<0.01]。差速贴壁需要充分的时间,15min组和30min组在提高星形胶质细胞纯度方面无明显差别。②差速贴壁培养组星形胶质细胞积分吸光度值高于常规培养组(常规培养组:528±25,差速贴壁培养组15min:972±17,差速贴壁培养组30min:996±35,P<0.05)。结论:①差速贴壁技术可明显提高星形胶质细胞纯化度,并且星形胶质细胞生长状态明显优于常规培养方法。②最佳差速贴壁时间为15min,过长差速贴壁时间对提高星形胶质细胞纯度无明显影响。  相似文献   
103.
104.
BACKGROUND: Spontaneous bacterial peritonitis (SBP) is a serious complication of cirrhosis with ascites, having high recurrence despite antibiotic prophylaxis. Small bowel dysmotility and bacterial overgrowth have been documented to be related to SBP. The purpose of the present paper was (i) to study whether addition of a prokinetic agent to norfloxacin ameliorates the development of SBP in high-risk patients; and (ii) to identify risk factors for SBP development. METHODS: A prospective, single blinded, randomized controlled trial was conducted in high-risk cirrhotic patients with ascites who had either recovered from an episode of SBP or who had low ascitic fluid protein. Norfloxacin 400 mg once daily (group I) or norfloxacin 400 mg once daily with cisapride 20 mg twice a day (group II) was given and occurrence of side-effects of therapy and mortality were recorded. RESULTS: Of the 94 patients, 48 (51%) were in group I, and 46 (49%) in group II. The actuarial probability of developing SBP at 12 month in group I was 56.8% and in group II, 21.7% (P = 0.026). Treatment failure was observed in five patients (10%) in group I and none in group II (P = 0.003). The actuarial probability of death at 18 months was 20.6% in group I and 6.2% in group II (P = 0.1). Low serum albumin, low ascitic fluid protein and alcoholic cirrhosis were related to development of SBP (P < 0.05). Additionally, low serum albumin (2.8 g/dL), gastrointestinal bleeding, alcoholic cirrhosis and low ascitic fluid protein were significantly associated with multiple occurrences of SBP. CONCLUSIONS: Prophylaxis with norfloxacin and cisapride significantly reduces the incidence of SBP in high-risk cirrhosis patients; low serum albumin, low ascitic fluid protein and alcoholic cirrhosis predispose to the development of SBP in high-risk cirrhosis patients; and low ascitic fluid protein should also be considered as a risk factor for the development of SBP requiring prophylaxis.  相似文献   
105.
In countries with intermediate or high endemicity for chronic hepatitis B virus (HBV) infection, exacerbations of chronic hepatitis B (CHB) are common. We studied the clinical, biochemical, and virologic characteristics of patients first presenting clinically with features of acute icteric hepatitis B, to identify features that might differentiate between acute viral hepatitis B (AVHB) from first episode of exacerbation of chronic hepatitis (ECHB). We retrospectively analyzed 79 patients (mean age 35.4 ± 14 years; M:F = 60:19) who first presented clinically as AVHB, within 4 weeks of onset of symptoms. Patients who on follow-up cleared HBsAg and/or did not develop any clinical, radiologic, or histologic evidence of chronic liver disease (CLD) were categorized as AVHB (group 1). Patients who had persistence of HBsAg and developed clinical, biochemical, radiologic, or histologic evidence of chronic liver disease were categorized as ECHB (group 2). Forty-nine patients were in group 1 and 30 in group 2. The 2 groups were comparable with respect to prodrome, onset of jaundice, serum bilirubin, ALT, prothrombin time prolongation, serum albumin, and A/G ratio. Among group 1 patients, 78% had IgM anti-HBc positive in titers > 1:1000; in group 2, there were negative or positive in titers < 1:1000 in 70% patients (P < .001). Forty-seven of 49 (95.9%) patients in group 1 had HBV-DNA levels < 0.5 pg/mL, whereas 26 of 30 (86.73%) patients in group 2 had levels > 0.5 pg/mL (P ≤ .001). Quantitative HBV DNA and IgM anti-HBc titers at initial presentation can differentiate patients with a true episode of acute hepatitis B from patients with first episode of symptomatic exacerbation of chronic hepatitis B. Clinical and biochemical features do not help in differentiating the two.  相似文献   
106.
BACKGROUND/AIMS: 1,25-dihydroxyvitamin-D is involved in immunomodulation. Expression of vitamin-D receptors in hepatocytes suggests its role in hepatocellular injury. We studied the association of single nucleotide polymorphisms in genes involved in immunoregulatory functions of vitamin-D with susceptibility, severity and persistence of HBV infection. METHODS: Five polymorphisms in VDR, CCR5, TNF-alpha and TNF-beta were studied in 214 chronic hepatitis B patients and 408 controls. Clinical parameters were compared between mild or severe liver disease patients. RESULTS: The frequency of heterozygosity of CCR5Delta32 was higher in chronic hepatitis B patients than controls (4.2 vs 0.73%, P=0.005). Frequency of VDR Apa1 a/a and TNF-beta A/A was higher in severe compared with mild liver disease based on HAI (19.3 vs 5.4%, P=0.003 and 18.1 vs 3.8%, P=0.001, respectively) and fibrosis score (23.7 vs 3.6%, P<0.001 and 18.1 vs 4.4%, P=0.002, respectively). The frequency of VDR a/a allele was also higher in patients with higher HBV DNA (11 vs 2.6%, P=0.002). Apa1 and Taq1 markers in VDR are in linkage-disequilibrium and 'at'haplotype is associated with severe liver disease. CONCLUSIONS: CCR5Delta32 heterozygosity was associated with susceptibility and VDR a/a, TNF-beta A/A with severity of HBV-related liver disease and VDR a/a allele with higher viral load. These results affirm an important role of immunogenetic factors in the outcome of chronic HBV infection.  相似文献   
107.
108.
Lipid targets can be difficult to attain in familial hypercholesterolaemia. To compare atorvastatin with simvastatin- fenofibrate and simvastatin-cholestyramine therapy, we studied 54 patients with familial hypercholesterolaemia over periods of 2-6 months on each therapeutic regimen. The atorvastatin regimen reduced total cholesterol by 41.2 +/- 11.2%, LDL by 45.6 +/- 15.5%, triglycerides by 33.8 +/- 24.8%, and increased HDL by 2.3 +/- 37.0%. Simvastatin- fenofibrate therapy achieved reductions of 33.9 +/- 8.5% in cholesterol, 42.0 +/- 12.2% in LDL, 34.7 +/- 38.3% for triglycerides, and a 25.4 +/- 55.1% increase in HDL. Simvastatin-cholestyramine gave a reduction of 31.3 +/- 11.8% in cholesterol, 36.0 +/- 14.4% in LDL, 13.7 +/- 36.3% in triglycerides, and a 1.1 +/- 30.3% rise in HDL. The atorvastatin regimen was marginally but not significantly better than simvastatin-fenofibrate in improving the LDL:HDL ratio, LDL:apoB and and apolipoprotein B:A1 ratios. Eleven patients (20.4%) had side- effects: two discontinued atorvastatin due to side-effects; two patients had rashes; six had myalgia and two had diarrhoea. Gastrointestinal side-effects were described in 16 (30.1%) patients on simvastatin-cholestyramine therapy and four cases of myalgia (11.2%) were seen with simvastatin-fenofibrate. In nine patients on atorvastatin (20.4%) a 30% or greater fall in HDL was observed, compared to five patients with resin therapy (9.2%) and two with fibrate therapy (5.5%). There were no significant differences in liver or muscle biochemistry between the regimens, but atorvastatin did raise transaminase and creatine kinase concentrations significantly compared to pre-treatment values (p = 0.001). Atorvastatin significantly improves the lipid profile in most patients compared with other regimens. It has a comparable incidence of side-effects to combination therapy regimens.   相似文献   
109.
Background and Aim: Hepatitis E virus (HEV) has recently been implicated in episodes of acute decompensation in patients having underlying chronic liver disease (CLD) of varying etiology. However, HEV as a cause of acute exacerbation of previously asymptomatic and unrecognized hepatitis B virus (HBV)‐infected patients is less well described. The aim of the present study was to investigate the etiology of acute exacerbation of previously asymptomatic and unrecognized HBV‐infected patients and to evaluate the relative role of HEV. We also investigated the effect of superinfection on the clinical spectrum of underlying HBV infection. Methods: Forty‐three patients presented with the following were retrospectively analyzed: (i) clinical features suggestive of acute hepatitis; (ii) with hepatitis B surface antigen (HBsAg) (+); (iii) IgM hepatitis B core antibody (IgM anti‐HBc) (?); (iv) no previous history of liver disease; (v) no features suggestive of CLD at presentation; (vi) HBsAg remaining (+) for at least 12 months on follow up; and (vii) having a follow‐up biopsy during the convalescent phase showing evidence of chronic hepatitis B. Results: Of the 43 patients, 21 were hepatitis e antigen (HBeAg) (+) (Gr.1) and 22 HBeAg (?) (Gr.2) at presentation. In Gr.1, only two (9.5%) had superinfection (both with hepatitis A virus), whereas in Gr.2, 11 (50%) had superinfection (27.3% hepatitis E, 13.6% hepatitis A and 9.1% both) (P = 0.007). In Gr.1, the remaining 19 (90.5%) patients had spontaneous exacerbation (immune clearance with spontaneous seroconversion) whereas in Gr.2, the remaining 11 (50%) had spontaneous exacerbation (due to reactivation). Overall, HEV superinfection contributed to 20% of acute exacerbation episodes and, in particular, 36% of episodes in initially HBeAg (?) patients. Time to alanine aminotransferase normalization was longer in patients with superinfection (n = 13) as compared to spontaneous exacerbation (n = 30) (median [range] 36 [8–48]vs 16 [6–36] weeks, P = 0.001). During convalescence, there was no significant difference between histological activity index score (median [range] 8 [4–11]vs 8 [4–16] weeks, P = 0.629) and fibrosis scores (median [range] 3.5 [1–4]vs 2 [1–4] weeks, P = 0.099] on liver biopsy after recovery among patients with acute exacerbation due to superinfection and spontaneous exacerbation. Conclusions: Acute exacerbations in HBeAg (+) patients are most often due to spontaneous viral activation, while in HBeAg (?) patients, superinfection with non‐B hepatitis viruses and spontaneous viral activation are equally common. HEV is an important cause of acute exacerbation in previously asymptomatic and unrecognized patients with HBV‐related CLD.  相似文献   
110.
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