首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   8928篇
  免费   268篇
  国内免费   180篇
耳鼻咽喉   51篇
儿科学   357篇
妇产科学   185篇
基础医学   657篇
口腔科学   241篇
临床医学   987篇
内科学   1457篇
皮肤病学   104篇
神经病学   1081篇
特种医学   153篇
外科学   1090篇
综合类   665篇
现状与发展   4篇
一般理论   2篇
预防医学   1082篇
眼科学   157篇
药学   461篇
  4篇
中国医学   119篇
肿瘤学   519篇
  2024年   32篇
  2023年   296篇
  2022年   353篇
  2021年   522篇
  2020年   409篇
  2019年   276篇
  2018年   286篇
  2017年   247篇
  2016年   243篇
  2015年   208篇
  2014年   473篇
  2013年   695篇
  2012年   307篇
  2011年   368篇
  2010年   276篇
  2009年   363篇
  2008年   367篇
  2007年   375篇
  2006年   313篇
  2005年   331篇
  2004年   273篇
  2003年   215篇
  2002年   187篇
  2001年   184篇
  2000年   144篇
  1999年   153篇
  1998年   156篇
  1997年   115篇
  1996年   129篇
  1995年   105篇
  1994年   104篇
  1993年   83篇
  1992年   74篇
  1991年   81篇
  1990年   64篇
  1989年   65篇
  1988年   58篇
  1987年   43篇
  1986年   58篇
  1985年   69篇
  1984年   60篇
  1983年   35篇
  1982年   42篇
  1981年   33篇
  1980年   29篇
  1979年   14篇
  1978年   15篇
  1977年   10篇
  1976年   13篇
  1975年   14篇
排序方式: 共有9376条查询结果,搜索用时 15 毫秒
991.
背景:虽然经前路椎体融合应用于颈椎退行性疾病的治疗超过50年,但至今对其技术的标准化仍然存在争议.单独使用椎间融合器最主要的缺点是即时稳定性欠佳和融合器下沉;椎间融合器配合前路钛板最主要的缺点是术后钛板区域吞咽困难及手术间盘周围异位骨化.目的:对比新的内置物Zero-P和传统椎间融合器加钛板治疗神经根颈椎病的临床疗效及影射学结果.方法:回顾性分析56例行颈椎前路减压植骨融合内固定神经根型颈椎病患者的临床资料,根据内固定方案分为两组:Zero-P组患者25例共31个节段,传统组(传统椎间融合器+锁定钛板)患者31例共40个节段,两组患者年龄、性别及手术节段位置差异均无显著性意义;比较两组患者的颈椎功能障碍指数、吞咽困难发生率、Cobb C角、Cobb S角、椎体高度、椎体稳定性及异位骨化程度.结果与结论:两组患者内固定后24个月时的颈椎功能障碍指数明显低于内固前(P<0.05),内固定后患者症状明显好转.Zero-P有1例内固定后早期发生吞咽困难,24个月随访时症状消失;传统组2例内固定后发生吞咽困难,两组吞咽闲难发生率差异无显著性意义(P>0.05).两组Cobb C角及手术节段椎体高度在内固前与内固定后比较差异无显著性意义(P>0.05).Cobb S角Zero-P组患者在内固前至内固定后(即手术过程时间)呈明显增加趋势,最大值出现在内固定后第1次复查时;而传统组内固前至内固定后6周时Cobb S角呈缓慢增加趋势,内固定后6周左右Cobb S角达到最大值.Zero-P组融合节段均获得牢固骨性融合,而传统组31例患者中有30例均牢固骨性融合,稳定率达到97%.内固定后24个月随访发现,Zero-P组异位骨化发生率为25%,传统组异位骨化发生率为44%,Zero-P组内固定后24个月时的异位骨化率显著低于传统组(P<0.05).提示与传统钉板系统相比,Zero-P?  相似文献   
992.
背景:脊柱的刚性固定融合是修复腰椎退变和不稳的传统方法,但是还存在相应的并发症,临床满意率不高。Waveflex是一种非融合椎弓根螺钉半刚性固定系统,它能适当的维持节段间正常运动,保留及恢复受损髓核的功能,而且对临近节段无不利影响。目的:对后路Waveflex非融合椎弓根螺钉弹性固定结合小开窗髓核摘除修复腰椎间盘突出症进行短期疗效评价。方法:纳入腰椎间盘突出症患者64例,其中弹性固定组34例行腰椎后路小开窗髓核摘除结合Waveflex弹性固定,髓核摘除组30例行单纯髓核摘除。随访分析患者疗效和并发症,定期进行腰痛目测类比评分、下腰痛日本骨科协会评分、Oswestry功能障碍指数评估,并复查腰椎正侧位X射线片及MRI,测量相关指标。结果与结论:患者术后随访12-22个月。两组末次随访腰痛目测类比评分、下腰痛日本骨科协会评分、Oswestry功能障碍指数均较治疗前明显改善(P〈0.05),动态固定组末次随访腰痛的缓解率优于较髓核摘除组(P〈0.05)。末次随访弹性固定组手术节段的活动范围小于治疗前,而椎间盘高度及MRI T1值大于治疗前(P〈0.05)。髓核摘除组末次随访和治疗前相比未发生明显变化。末次随访两组间比较,弹性固定组在控制手术节段过度随意移动、椎间高度及髓核修复上要优于髓核摘除组,而对邻近节段的影响与髓核摘除组无明显差异。提示与单纯髓核摘除相比,Waveflex系统结合小开窗髓核摘除修复腰椎间盘突出症具有满意的近期疗效,且对手术节段稳定性及髓核修复有积极作用,近期不会导致邻近节段退变。  相似文献   
993.
目的:探讨家庭随访对慢性精神分裂症患者康复的影响。方法将100例出院的精神分裂症患者随机分为两组,每组50例,两组均接受常规药物维持治疗和一般健康教育,在此基础上观察组实施家庭随访,观察12个月。采用护士用住院病人观察量表、日常生活能力量表、康复状态量表及社会功能缺陷筛选量表评定随访效果。结果随访各时段观察组护士用住院病人观察量表总积极因素及病程总估计评分均显著高于对照组(P<0.01),总消极因素评分显著低于对照组( P<0.01);随访第12个月日常生活能力量表、康复状态量表及社会功能缺陷筛选量表评分均显著低于对照组(P<0.01)。结论家庭随访能有效缓解精神分裂症患者的阴性症状,改善社会功能,提高生活能力,对促进患者的全面康复具有重要作用。  相似文献   
994.
995.
目的分析肺癌术后患者电话随访应答情况及其相关影响因素,并探讨提高肺癌术后患者电话随访应答率的对策。方法对1608例行胸外科手术治疗的肺癌患者进行电话随访,计算其应答率,分析影响患者应答率的相关因素。结果1608例肺癌术后患者随访总应答率为83.1%。预留电话类型、电话个数、肿瘤家族史均是影响肺癌术后患者电话随访应答率的主要因素(P0.05)。结论肺癌术后患者电话随访应答率不太理想。加强与患者的沟通,告知随访对促进患者康复的意义,提高患者及家属对定期复查和与医院保持良好沟通的重要性的认识可提高患者随访应答率和随访质量。  相似文献   
996.
目的探讨PDCA循环路径在老年高血压患者社区跟踪护理中的应用方法及效果。方法 2012年1-12月,按随机数字表法将怀化市鹤城区迎丰社区板桥铺街道的76例老年高血压患者分为观察组和对照组各38例,两组患者均接受常规抗高血压治疗,观察组患者在此基础上运用PDCA循环进行社区跟踪护理干预,观察两组患者血压控制、并发症、焦虑、抑郁及一般自我效能感。结果干预后,观察组患者的血压控制达标率和并发症发生率分别为73.68%(28/38)、13.16%(5/38),对照组分别为42.11%(16/38)、28.94%(11/38),两组比较差异均有统计学意义(均P0.01)。两组干预前的SAS、SDS和GSES评分比较,差异均无统计学意义(均P0.05);干预后观察组SAS评分和SDS评分低于对照组,而GSES评分高于对照组,差异均有统计学意义(均P0.05)。结论运用PDCA循环对老年高血压患者实施社区跟踪护理可提高疾病治疗效果,增强患者的自我效能感,有效改善患者抑郁焦虑的心理状态,从而提高患者的生活质量。  相似文献   
997.
经皮二尖瓣扩张术治疗老年及老年前期患者二尖瓣狭窄   总被引:1,自引:0,他引:1  
目的 探讨经皮经房间隔穿刺二尖瓣扩张治疗老年和老年前期患者二尖瓣狭窄的临床意义。方法  86例患者采用一步法经皮经房间隔穿刺球囊扩张治疗二尖瓣狭窄。手术前后分别记录右心房压、左心房压、肺动脉压 ,二尖瓣口面积 ,并进行手术后随防。结果  86例患者中 83例治疗成功 ,3例失败 ,其中 1例为术中急性心包填塞 ,2例术后出现中度二尖瓣反流。术后即刻 ,左心房压、肺动脉压下降 ,二尖瓣口面积增加 ,心功能改善。 4 2例患者随访(4 .4± 2 .1)年 ,1例出现再狭窄 ,1例原因不明猝死 ,1例因二尖瓣反流行瓣膜置换术 ,其余患者心功能和生活质量明显改善。结论 对年龄≥ 5 0岁伴轻度二尖瓣和 (或 )主动脉瓣反流 ,瓣膜钙化或瓣下结构病变的二尖瓣狭窄患者 ,可安全有效地施行球囊二尖瓣成形术。  相似文献   
998.
OBJECTIVE: Although longitudinal care constitutes the bulk of primary care, physicians receive little guidance on the fundamental question of how to time follow-up visits. We sought to identify important predictors of the revisit interval and to describe the variability in how physicians set these intervals when caring for patients with common medical conditions. DESIGN: Cross-sectional survey of physicians performed at the end of office visits for consecutive patients with hypertension, angina, diabetes, or musculoskeletal pain. PARTICIPANTS/SETTING: One hundred sixty-four patients under the care of 11 primary care physicians in the Dartmouth Primary Care Cooperative Research Network. MEASUREMENTS: The main outcome measures were the variability in mean revisit intervals across physicians and the proportion of explained variance by potential determinants of revisit intervals. We assessed the relation between the revisit interval (dependent variable) and three groups of independent variables, patient characteristics (e.g., age, physician perception of patient health), identification of individual physician, and physician characterization of the visit (e. g., routine visit, visit requiring a change in management, or visit occurring on a "hectic" day), using multiple regression that accounted for the natural grouping of patients within physician. MAIN RESULTS: Revisit intervals ranged from 1 week to over 1 year. The most common intervals were 12 and 16 weeks. Physicians' perception of fair-poor health status and visits involving a change in management were most strongly related to shorter revisit intervals. In multivariate analyses, patient characteristics explained about 18% of the variance in revisit intervals, and adding identification of the individual provider doubled the explained variance to about 40%. Physician characterization of the visit increased explained variance to 57%. The average revisit interval adjusted for patient characteristics for each of the 11 physicians varied from 4 to 20 weeks. Although all physicians lengthened revisit intervals for routine visits and shortened them when changing management, the relative ranking of mean revisit intervals for each physician changed little for different visit characterizations-some physicians were consistently long and others were consistently short. CONCLUSION: Physicians vary widely in their recommendations for office revisits. Patient factors accounted for only a small part of this variation. Although physicians responded to visits in predictable ways, each physician appeared to have a unique set point for the length of the revisits interval.  相似文献   
999.

Objectives

This study sought to describe the impact of statins on individual coronary atherosclerotic plaques.

Background

Although statins reduce the risk of major adverse cardiovascular events, their long-term effects on coronary atherosclerosis remain unclear.

Methods

We performed a prospective, multinational study consisting of a registry of consecutive patients without history of coronary artery disease who underwent serial coronary computed tomography angiography at an interscan interval of ≥2 years. Atherosclerotic plaques were quantitatively analyzed for percent diameter stenosis (%DS), percent atheroma volume (PAV), plaque composition, and presence of high-risk plaque (HRP), defined by the presence of ≥2 features of low-attenuation plaque, positive arterial remodeling, or spotty calcifications.

Results

Among 1,255 patients (60 ± 9 years of age; 57% men), 1,079 coronary artery lesions were evaluated in statin-naive patients (n = 474), and 2,496 coronary artery lesions were evaluated in statin-taking patients (n = 781). Compared with lesions in statin-naive patients, those in statin-taking patients displayed a slower rate of overall PAV progression (1.76 ± 2.40% per year vs. 2.04 ± 2.37% per year, respectively; p = 0.002) but more rapid progression of calcified PAV (1.27 ± 1.54% per year vs. 0.98 ± 1.27% per year, respectively; p < 0.001). Progression of noncalcified PAV and annual incidence of new HRP features were lower in lesions in statin-taking patients (0.49 ± 2.39% per year vs. 1.06 ± 2.42% per year and 0.9% per year vs. 1.6% per year, respectively; all p < 0.001). The rates of progression to >50% DS were not different (1.0% vs. 1.4%, respectively; p > 0.05). Statins were associated with a 21% reduction in annualized total PAV progression above the median and 35% reduction in HRP development.

Conclusions

Statins were associated with slower progression of overall coronary atherosclerosis volume, with increased plaque calcification and reduction of high-risk plaque features. Statins did not affect the progression of percentage of stenosis severity of coronary artery lesions but induced phenotypic plaque transformation. (Progression of AtheRosclerotic PlAque DetermIned by Computed TomoGraphic Angiography Imaging [PARADIGM]; NCT02803411)  相似文献   
1000.
AIMS: This study compared 5-year treatment outcomes of older adults to those of middle-aged and younger adults in a large managed care chemical dependency program. We examined age group differences in individual, treatment and extra-treatment factors, which may influence long-term outcome. DESIGN: Seventy-seven per cent of original study participants completed a telephone interview 5 years after out-patient chemical dependency treatment at Kaiser Permanente. This sample (N = 925) included 65 patients aged 55-77, 296 patients aged 40-54 and 564 patients aged 18-39 (age at baseline). MEASUREMENTS: Measures at follow-up included alcohol and drug use, Addiction Severity Index (ASI), Alcoholics Anonymous Affiliation Scale, social resource and self-reported health questions. Mortality data were obtained from contact with family members of patients as well as automated health plan records. FINDINGS: Older adults were less likely to be drug-dependent at baseline than younger and middle-aged adults, and had longer retention in treatment than younger adults. At 5 years, older adults were less likely than younger adults to have close family or friends who encouraged alcohol or drug use. Fifty-two per cent of older adults reported total abstinence from alcohol and drugs in the previous 30 days versus 40% of younger adults. Older women had higher 30-day abstinence than older men or younger women. Among participants dependent only on alcohol, there were no significant age differences in 30-day abstinence. In logistic regression analysis, age group was not significant. Variables associated with greater age that independently predicted 30-day abstinence in the logistic regression model included longer retention in treatment and having no close family or friends who encouraged alcohol or drug use at 5 years; female gender was also significant. CONCLUSIONS: Results indicate that older adults have favorable long-term outcome following treatment relative to younger adults, but these differences may be accounted for by variables associated with age such as type of substance dependence, treatment retention, social networks and gender. Age differences in these characteristics inform intervention strategies to support long-term recovery of older adults and provide direction for investigation of how age affects outcome.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号