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71.
目的:通过使用CT三维测量髋臼发育情况及髋臼对股骨头覆盖率对比性观察,整体反映髋臼发育情况。方法:①观察对象:选择2003-06/2005-04对41例发育性髋关节脱位患者55个髋关节。其中男12例,女29例;年龄18个月~6岁。患髋右侧23例,左侧32例,其中双侧12例。健康侧27髋。患儿家属均知情同意。②实验方法:所有患儿使用PQ6000型多层螺旋CT扫描,扫描数据进行骨组织三维重建。将测量数据制成图表,显示三维的髋臼发育情况,并量化表示髋臼的缺损情况。③实验评估:计算不同截面正常侧髋臼指数、中心边缘角(假设符合正态分布)的均数、标准差、分布范围及95%可信区间。观察发育性髋关节脱位术前术后骨骼形态学变化。分别在术前、术后测量患者患侧髋臼指数、中心边缘角和前倾角,测量值均分别与正常值进行对比。结果:患侧55个髋,健康侧27髋,均进入结果分析。①发育性髋关节脱位术前术后骨骼形态学变化:术前55侧发育性髋关节脱位髋关节脱位程度为,参照T"nnis分类方法,Ⅰ度5髋(9.1%),Ⅱ度11髋(20%),Ⅲ度32髋(58.2%),Ⅳ度7髋(12.7%)。术后患者均表现髋臼α角均>90°,头臼呈同心圆对位,Shenton线连续,股骨头较术前明显发育,原先未出现头骺的患者,出现头骺,但较正常仍偏小;髋臼口呈类圆形,髋臼边缘欠光滑,髋臼整体呈一定程度前倾。②术前术后髋臼指数、中心边缘角和前倾角变化对比:术后患者的髋臼指数和前倾角与正常对照组之间差异无显著性(P>0.05),术后患者的中心边缘角大于正常对照组[(33.4±2.6)°(29.1±2.0)°,P<0.01],术后患者的髋臼指数和前倾角测量值均小于术前(P<0.01)。结论:介绍了一种对髋臼形态测量的新方法,它能够全面反映髋臼的发育情况,不但增加了对中心边缘髋臼病理改变的认识程度,还为手术提供了精确的可信度较高的矫形设计方案。  相似文献   
72.
BACKGROUND: Polyethylene glycol (PEG) has been shown to potentiate antigen-antibody reactions. STUDY DESIGN AND METHODS: To investigate the utility of PEG in pretransfusion testing, a blinded comparison study of PEG and a low-ionic-strength additive solution (LISS) was conducted. A total of 500 patient samples were tested in parallel with reagent antibody-detection cells using blind-coded PEG and LISS potentiators. RESULTS: In 34 (34%) of 100 samples with known antibodies in the Rh, Kell, Duffy, Kidd, and MNS systems, PEG antiglobulin reactions were stronger (total score, 382) than LISS antiglobulin reactions (total score, 216), and in 66 cases (66%), they were equal to those of LISS. Of 400 samples without detectable antibodies, 384 were negative with PEG and LISS, and 16 were positive in PEG tests and negative in LISS. Seven of the 16 were clinically important antibodies (D, 1; E, 3; Fya, 1; Jka; 1; Jkb, 1), and four were clinically benign antibodies (Le(a), 2; McCc, 1; Sda, 1). Five of the 16 demonstrated inconclusive PEG reactions, for a false-positive rate of 5 in 400 (1.3%). Of the 500 samples, none was negative in PEG tests and positive in LISS (0% false-negative rate). CONCLUSION: Although PEG demonstrates a relatively high false-positive rate, PEG is more sensitive than LISS in detecting clinically significant antibodies.  相似文献   
73.
目的:观察大黄苷元联合溶栓治疗对大鼠脑缺血损伤肺胃组织的保护作用。方法:实验于2005-08/2006-07在河南中医学院老年医学研究所实验室完成。①260只SD大鼠采用随机数字法分为假手术组20只、模型组60只、尿激酶组60只、大黄苷元组60只、大黄苷元 尿激酶组60只;除假手术组外,其余各组根据缺血后动脉用药时间又各分为3,6,9h3个时间点,每个时间点20只。②自体血栓结合线栓阻塞大鼠大脑中动脉制备局灶性脑缺血动物模型。③各组大鼠均于术前4d灌胃用药,大黄苷元组、大黄苷元 尿激酶组用大黄苷元灌胃(灌胃体积为每100g大鼠1mL),假手术组、模型组和尿激酶组用等体积的生理盐水灌胃;动脉用药除假手术组外,其余各组分别于造模后3,6,9h经导管由区域动脉给药,尿激酶组与大黄苷元 尿激酶组用尿激酶(用药体积为20μL),模型组和大黄苷元组区域动脉用同等体积的生理盐水。④动脉给药后24h,观察大鼠脑组织病理损伤、颅内和胃出血率、脑和肺组织含水量、肺和胃病理损伤变化。结果:实验过程中因麻醉、操作等原因死亡及剔除大鼠156只,进入结果分析104只。①颅内和胃出血率:尿激酶组9h大鼠颅内出血率较模型组高(66.67%,28.57%,P<0.05);尿激酶组9h脑和胃出血率较3h高(脑:66.67%,18.75%;胃:41.18%,17.65,P<0.05);大黄苷元 尿激酶组9h颅内出血率较尿激酶组9h低(P<0.05)。②脑和肺及胃组织病理改变:各模型组大鼠脑、胃和肺组织病理损伤均较假手术组明显;各用药组脑和肺组织分别较相应时间模型组减轻;各组脑、胃和肺组织损伤9h均较其3h明显;大黄苷元 尿激酶组9h较相应时间点尿激酶组和大黄苷元组损伤减轻(P<0.05)。③脑和肺组织含水量:各模型组脑和肺组织含水量均较假手术组增高(P<0.01);尿激酶组和大黄苷元 尿激酶组各时间点均较模型组降低(P<0.01);各组9h分别较其3h脑和肺含水量增加(P<0.01,P<0.05);大黄苷元 尿激酶组6h脑组织和9h肺含水量分别较尿激酶组降低(P<0.05)。结论:脑缺血后延迟溶栓治疗可引起大鼠脑和胃出血率增高、脑组织和肺组织水肿加重,脑和肺及胃组织病理损伤明显;大黄苷元联合溶栓可降低脑出血率,改善神经细胞超微结构,降低脑和肺组织含水量,对脑缺血肺和胃组织损伤具有保护作用。  相似文献   
74.
75.
目的:建立家猪胸腰段脊髓火器贯通伤模型和改良Allen's打击伤后全瘫模型,观察伤后促凋亡基因p53基因的早期表达。方法:实验于2005-05/08在解放军第一七五医院实验室完成。取健康雄性家猪20只,单纯随机分为3组:①火器伤组:9只,在全麻状态下制作胸腰段(L1~L2)脊髓火器伤模型,分为伤后1,3,6h3个时间处死。②打击伤组:9只,L1节段脊髓行改良Allen’s打击,致伤力为500g·cm,处死时间同前。③空白对照组:2只,只麻醉,不造模,伤后6h处死。伤后不同时间点(伤后1,3,6h)和不同节段(伤点、近伤点、中伤点及远伤点)取材,采用SP法进行P53蛋白免疫组化染色,用TJTY-300型全自动图像分析仪测量P53免疫组织化学染色阳性物质吸光度。结果:经补充后20只猪进入结果分析。①脊髓损伤后3h打击伤组伤点,火器伤组近伤段脊髓P53蛋白的表达高于空白对照组(P<0.001),随着时间推移,打击伤组和火器伤组P53蛋白的表达呈升高趋势(P<0.001),且火器伤组要高于打击伤组(P<0.0001)。②在脊髓损伤后6h,打击伤组仅在伤点和近伤段P53蛋白的表达高于空白对照组(5.57±0.82,3.21±0.43,P<0.05),而火器伤组近伤段、中伤段及远段伤均高于空白对照组(6.46±0.66,4.27±0.39,1.16±0.17,P<0.05)。结论:①细胞凋亡基因p53在脊髓损伤中的表达有一定的时空性,在脊髓损伤后3h出现P53蛋白表达量的增加。②脊髓火器伤的波及范围较打击伤更为广泛。  相似文献   
76.
目的:对比观察硬膜外隙注药与腰椎定点牵压疗法及其联合应用治疗腰椎间盘突出症的疗效。方法:①选择2004-01/2006-01解放军总医院康复医学科门诊诊治的腰椎间盘突出症患者180例,男125例,女55例,年龄20~65岁。患者对治疗方案知情同意。按随机数字表法将患者分为3组:硬膜外隙注药组、腰椎定点牵压疗法组、联合治疗组,每组60例。硬膜外隙注药组:骶管注射利多卡因注射液、胞二磷胆碱、维生素B12、地塞米松混合液,每5d注射1次,共4次。腰椎定点牵压疗法组:采用胸带与下肢固定带牵引,待牵引床启动逐渐使患者腰脊柱拉伸时,术者双手拇指关节突关节连线,由上腰段向腰骶段滑行推压,当拇指推压到病变间隙时,牵引力须达到患者体质量1.5倍左右,迅速向脊柱前方施压。共2次。联合治疗组为两种疗法联合应用。每2次硬膜外隙注药后施行腰椎定点牵压疗法疗法1次,共2次。②于治疗前和治疗后3,6个月采用疼痛强度评分评估疼痛程度(0~10分,0分为无痛,10分为最痛),治疗前和治疗后3个月观察临床体征和评估疗效,疗效评估依据胡有谷的腰椎间盘突出症和国家中医药管理局(1994年)制定的中医病症诊断疗效标准。③计量和计数资料差异比较分别采用t检验和χ2检验。结果:腰椎间盘突出症患者180例均进入结果分析。①疼痛强度变化:治疗后3个月3组疼痛强度评分均较治疗前降低,其中联合治疗组与治疗前比较,差异明显(χ2=2.13,P<0.01)。治疗后6个月,各组病例的疼痛症状大多数获得控制,其中联合治疗组疼痛强度评分与治疗前比较,差异明显(χ2=4.03,P<0.01),联合治疗组和硬膜外隙注药组疼痛强度评分明显低于腰椎定点牵压疗法组(χ2=5.62,6.16,P<0.05)。②临床体征变化:各组治疗后3个月4项体征均较治疗前改善,其中联合治疗组直腿抬高试验阳性患者数明显少于硬膜外隙注药组和腰椎定点牵压疗法组(7,19,14例,χ2=9.24,9.14,P<0.01)。③疗效:联合治疗组治疗有效率明显高于其他硬膜外隙注药组和腰椎定点牵压疗法组[100%(60/60),88%(53/60),92%(55/60),χ2=6.26,6.04,P<0.01],而其他2组间比较,差异不明显(χ2=8.63,P>0.05)。结论:硬脊膜外注药及腰椎定点牵压疗法均是治疗腰椎间盘突出症的有效疗法,联合应用疗效更好。  相似文献   
77.
Most Ig receptors exist as hetero-oligomeric complexes with separate ligand binding (alpha) and signal transducing (beta, gamma, or zeta) subunits. For Fc gamma RIIIa and Fc epsilon RI, association with the FcR gamma-chain is essential for surface expression. However, the human high affinity IgG receptor, hFc gamma RI, was found to be surface- expressed by itself in transient transfection models. We have now analyzed the integrity of hFc gamma RI expression in more detail in stable transfectants. In vitro we noted that, in the absence of FcR gamma-chain, surface expression of hFc gamma RI rapidly declined to background levels, in both IIA1.6 B cells and NIH3T3 fibroblasts. The effect of FcR gamma-chain on hFc gamma RI surface expression in vivo was evaluated by using two newly generated transgenic mouse lines, selectively expressing hFc gamma RI on myeloid cells. These transgenic mice were crossed with FcR gamma-chain-deficient mice. Analysis of blood monocytes and peritoneal macrophages showed that surface expression of hFc gamma RI was reduced by approximately 80%. The remaining approximately 20% of receptors were still capable of binding IgG-opsonized RBC, suggesting FcR gamma-chain not to be critical for hFc gamma RI ligand-binding capacity. Importantly, however, hFc gamma RI signaling capacity was lost in FcR gamma-chain-deficient cells. No phagocytosis could be observed using either ligand sensitized (EA- IgG2a) or CD64-targeted erythrocytes (using a bispecific antibody) in both hFc gamma RI transgenic lines. This documents the FcR gamma-chain to be indispensable for both surface membrane expression and function of human Fc gamma RI in vivo.  相似文献   
78.
A multilaboratory study was conducted to develop a system for standardizing alanine aminotransferase (ALT) acceptability criteria ("cutoffs") for donated blood. Without standardized cutoffs, each laboratory must develop its own cutoff, and this may not make optimal use of ALT testing to reduce transmission of non-A, non-B hepatitis (NANB). Defining an ALT acceptability criterion in absolute terms is necessary because relative cutoffs based on local donor populations may be affected by the prevalence of NANB in each community. This study involved 16 laboratories using 23 different analytic systems. The ALT results of the analysis of a plasma reference sample could be used to translate mathematically a single, absolute cutoff to units applicable to each analytic system. The distribution of ALT results in 1.4 million donations from across the country was established; basing the cutoff on this sample avoids the problems inherent in using a local donor base to establish a cutoff. We propose the implementation of a system to standardize ALT acceptability criteria to an activity level defined by analysis of a nationwide donor sample.  相似文献   
79.

Objectives

The aim of the study was to describe growth and body composition changes in HIV‐positive children after they had initiated or changed antiretroviral therapy (ART) and to correlate these with viral, immune and treatment parameters.

Methods

Ninety‐seven prepubertal HIV‐positive children were observed over 48 weeks upon beginning or changing ART. Anthropometry and bioelectrical impedance analysis results were compared with results from the National Health and Nutrition Examination Survey 1999–2002 (NHANES) to generate z‐scores and with results for HIV‐exposed, uninfected children from the Women and Infants Transmission Study (WITS). Multivariate analysis was used to evaluate associations between growth and body composition and disease parameters.

Results

All baseline lean and fat mass measures were below those of controls from NHANES. Weight, height and fat free mass (FFM) index (FFM/height2) z‐scores increased over time (P=0.004, 0.037 and 0.027, respectively) and the waist:height ratio z‐score decreased (P=0.045), but body mass index and per cent body fat z‐scores did not change. Measures did not increase more than in uninfected WITS controls. In multivariate analysis, baseline height, mid‐thigh circumference and FFM z‐scores related to CD4 percentage (P=0.029, P=0.008 and 0.020, respectively) and change in FFM and FFM index z‐scores to CD4 percentage increase (P=0.010 and 0.011, respectively). Compared with WITS controls, baseline differences in height and mid‐thigh muscle circumference were also associated with CD4 percentage. Case–control differences in change in both subscapular skinfold (SSF) thickness and the SSF:triceps skinfold ratio were inversely associated with viral suppression. No measures related to ART class(es) at baseline or over time.

Conclusions

In these HIV‐positive children, beginning or changing ART was associated with improved growth and lean body mass (LBM), as indicated by FFM index. Height and LBM related to CD4 percentage at baseline and over time. Altered fat distribution and greater central adiposity were associated with detectable virus but not ART class(es) received.  相似文献   
80.

Objective

Acquired immune deficiency appears to be associated with serious non‐AIDS (SNA)‐defining conditions such as cardiovascular disease, liver and renal insufficiency and non‐AIDS‐related malignancies. We analysed the incidence of, and factors associated with, several SNA events in the LATINA retrospective cohort.

Materials and methods

Cases of SNA events were recorded among cohort patients. Three controls were selected for each case from cohort members at risk. Conditional logistic models were fitted to estimate the effect of traditional risk factors as well as HIV‐associated factors on non‐AIDS‐defining conditions.

Results

Among 6007 patients in follow‐up, 130 had an SNA event (0.86 events/100 person‐years of follow‐up) and were defined as cases (40 with cardiovascular events, 54 with serious liver failure, 35 with non‐AIDS‐defining malignancies and two with renal insufficiency). Risk factors such as diabetes, hepatitis B and C virus coinfections and alcohol abuse showed an association with events, as expected. The last recorded CD4 T‐cell count prior to index date (P=0.0056, with an average difference of more than 100 cells/μL) and area under the CD4 cell curve in the year previous to index date (P=0.0081) were significantly lower in cases than in controls. CD4 cell count at index date was significantly associated with the outcome after adjusting for risk factors.

Conclusions

The incidence and type of SNA events found in this Latin American cohort are similar to those reported in other regions. We found a significant association between immune deficiency and the risk of SNA events, even in patients under antiretroviral treatment.  相似文献   
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