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21.
An inhalation bioassay with Syrian golden hamsters is being conducted to evaluate the toxic and carcinogenic potential of cigarette sidestream smoke (SS) relative to mainstream smoke (MS). A Hamburg II smoking machine is used to deliver MS by nose-only exposure to hamsters and a modification allows for the simultaneous collection of SS for whole-body delivery to a different rack of animals. The tolerated dose of SS was determined by varying the air/smoke dilutions drawn through the animal restrainers. Preliminary data indicated that 20% carboxyhemoglobin (COHb) could be obtained in SS-exposed animals without fatality. Optimum exposure levels were determined. Monthly measurements of COHb, nicotine and cotinine indicate that the SS-exposed animals are absorbing slightly higher amounts of these smoke constituents than the MS-exposed hamsters. Tumor incidence and carcinogenicity data are being collected through complete necropsy and histology protocols and uptake data continue to be collected. These studies should help elucidate the carcinogenic potential of SS which has been suggested from its composition and from recent epidemiological data of cancer incidence in non-smokers.  相似文献   
22.
目的探讨完全腹腔镜Roux.en—Y吻合术式应用于远端胃癌根治术的安全性和可行性。方法回顾性分析福建省肿瘤医院腹部外科2012年8月至2013年3月对腹腔镜胃大部切除术后实施完全腹腔镜Roux.en—Y吻合术的20例胃癌患者的术中和术后临床资料。结果20例患者均成功实施完全腹腔镜远端胃癌根治术,无一例中转开腹或中转腹腔镜辅助手术。手术时间(190.8±53.6)min,术中出血量(122.4±57.7)ml,淋巴结清扫数(31.2±5.7)枚,术后病理切缘均为阴性。术后排气时间为(2.6±1.6)d,住院时间为(8.1±2.0)d。有1例术后出现肺部感染,但无吻合术相关并发症发生。结论完全腹腔镜Roux—en—Y吻合术式应用于远端胃癌根治术安全且可行。  相似文献   
23.
From a survey of all U.S. hospitals in 1976 and of a random sample in 1983, we found that the intensity of infection surveillance and control activities greatly increased, and the percentage of hospitals with an infection control nurse per 250 beds increased from 22% to 57%. The percentage with a physician trained in infection control remained low (15%), and there was a drop in the percentages of hospitals doing surgical wound infection surveillance (from 90% down to 79%) and reporting surgeon-specific rates to surgeons (from 19% down to 13%). There was an increase in the percentage of hospitals with programs shown to be effective in preventing urinary tract infections, bacteremias, and pneumonias, but not surgical wound infections. The percentage of nosocomial infections being prevented nationwide appears to have increased from 6% to only 9%, whereas 32% could be prevented if all hospitals adopted the most effective programs.  相似文献   
24.

Background

Patients referred to trauma centers often undergo an extensive diagnostic work-up before transfer. The purpose of our study was to quantify and examine the effects of repeat imaging in this population.

Methods

A prospective cohort study of 410 patient transfers was performed. Repeat imaging was conducted at the discretion of the accepting surgeon for multiple reasons. Two groups were compared, those who did and those who did not require repeat imaging.

Results

Overall, 53% of referrals received repeat imaging, at an average cost of $2,985 per patient. This group was older (42 vs 37 y; P < .05), more severely injured (injury severity score, 12 vs 9; P < .05), and experienced longer delays before transfer (244 vs 192 min; P < .05). By using logistic regression analysis, injury severity score was found to be an independent predictor of the need for repeat imaging (P = .003).

Conclusions

Severely injured trauma patients often receive films that ultimately require duplication, resulting in transfer delay, unnecessary morbidity, and increased resource use. Targeted education and development of centralized radiology systems could alleviate some of the burden of unnecessary imaging.  相似文献   
25.

Purpose

The aim of this study was to assess the risk of child abuse in children younger than 18 months admitted to a pediatric trauma service with lower extremity injuries.

Methods

An Institutional Review Board-approved retrospective case series of children admitted to a regional pediatric trauma center with lower extremity injuries from 1998 to 2002 (n = 5497) was performed. Factors analyzed included age, injuries, and injury mechanism.

Results

Among 5497 trauma patients, the incidence of abuse was 104 (2%) of 4942 children 18 months or older and 175(32%) of 555 children younger than 18 months (odds ratio [OR], 21.4 ± 2.9, P < .001). There were 1252 (23%) patients with lower extremity injuries in the entire sample, and 66 of these were younger than 18 months. In the extremity trauma group, for patients 18 months or older, 16 (1%) of 1186 were abused compared with 44 (67%) of 66 patients younger than 18 months (OR, 146 ± 53, P < .001). Among all trauma patients younger than 18 months, 41 of 55 lower extremity fractures were linked to abuse, whereas 134 of 500 other injuries were caused by abuse (OR, 8.0 ± 2.6, P < .001). Among the 41 abuse-related fractures, femur fracture was the most common (22), followed by tibia fracture (14).

Conclusions

Among children 18 months or older, abuse is an uncommon cause of lower extremity trauma. In children younger than 18 months, lower extremity injuries, particularly fractures, are highly associated with child abuse. Clinicians must thoroughly investigate lower extremity injuries in this age group.  相似文献   
26.
ObjectiveThe objective was to develop and operate a cloud-based federated system for managing, analyzing, and sharing patient data for research purposes, while allowing each resource sharing patient data to operate their component based upon their own governance rules. The federated system is called the Biomedical Research Hub (BRH).Materials and MethodsThe BRH is a cloud-based federated system built over a core set of software services called framework services. BRH framework services include authentication and authorization, services for generating and assessing findable, accessible, interoperable, and reusable (FAIR) data, and services for importing and exporting bulk clinical data. The BRH includes data resources providing data operated by different entities and workspaces that can access and analyze data from one or more of the data resources in the BRH.ResultsThe BRH contains multiple data commons that in aggregate provide access to over 6 PB of research data from over 400 000 research participants.Discussion and conclusionWith the growing acceptance of using public cloud computing platforms for biomedical research, and the growing use of opaque persistent digital identifiers for datasets, data objects, and other entities, there is now a foundation for systems that federate data from multiple independently operated data resources that expose FAIR application programming interfaces, each using a separate data model. Applications can be built that access data from one or more of the data resources.  相似文献   
27.
目的:明确以IgA沿肾小球毛细血管襻沉积为主的急进性肾小球肾炎的临床与病理特点。方法:分析解放军总医院全军肾脏病研究所收治的1例以IgA沿肾小球毛细血管襻沉积为主的急进性肾小球肾炎病例,分析其临床特点、病理与电镜特征,以及对强化免疫抑制治疗的反应。结果:该病例临床表现为急进性肾炎综合征,肾功能恶化发展迅速。但无肺出血及全身性血管炎症状。血清自身抗体系列、抗GBM抗体与ANCA均为阴性。病理光镜示肾小球环绕型新月体形成,肾小血管无炎症改变。冰冻切片与石蜡微波修复直接免疫荧光示IgA沿肾小球毛细血管襻细颗粒状沉积,间接免疫荧光法检测血清IgA型抗GBM为阴性;电镜示节段性上皮下、基底膜内及系膜区电子致密物沉积。对强化激素冲击与免疫抑制剂治疗效果欠佳。结论:本病例为特殊类型的急进性肾小球肾炎,根据其临床特点、血清学检测、免疫荧光及电镜检查结果,无法归于目前急进性肾炎的分型,对其临床特点应予重视。  相似文献   
28.
目的:研究老年性痴呆(AD)和血管性痴呆(VD)患者睡眠障碍的特点及相关性。方法:对31例AD患者和30例VD患者采用阿森斯(Athens)失眠量表调查评分及临床资料比较分析。对研究对象进行筛选分组。从8个方面详细记录睡眠情况,按量表现规定进行评定。结果:AD患者和VD患者总体睡眠状况比较有显著性差异(t=2.251,P<0.05)。睡眠状况各因子比较,在总睡眠质量、白天情绪、白天思睡等3个方面无显著性差异(P>0.05)。在早醒、白天身体功能方面,两者有极显著差异(P<0.01)。在入睡时间、夜间苏醒、总睡眠时间等两者存在显著性差异(P<0.05)。结论:AD患者和VD患者都有睡眠障碍,AD患者在早醒、白天身体功能、夜间苏醒、总睡眠时间等方面都比VD患者差,而VD患者在入睡时间上比AD患者明显延迟。  相似文献   
29.
目的探讨称重法和化学分析法评估人群矿物质摄入量的差异和相关性。方法同时使用称重法和化学分析法对89名上海市居民进行膳食调查,并对两种调查方法测得的钙、镁、铁、锌、铜、锰摄入量进行比较分析。结果称重法调查的6种矿物质元素的摄入量高于化学分析法(P<0.05),称重法调查的平均每天钙、镁、铁、锌、铜、锰摄入量比化学分析法分别高20.9%、67.4%、19.5%、84.4%、46.7%和33.3%;称重法与化学分析法测得的钙、镁、铁、锌、铜、锰摄入量均呈显著正相关(P<0.01),相关系数分别为0.571、0.672、0.521、0.524、0.538和0.691。结论称重法测得的人群膳食矿物质摄入量高于化学分析法。  相似文献   
30.
目的 探讨称重法和化学分析法评估人群矿物质摄入量的差异和相关性.方法 同时使用称重法和化学分析法对89名上海市居民进行膳食调查,并对两种调查方法测得的钙、镁、铁、锌、铜、锰摄入量进行比较分析.结果 称重法调查的6种矿物质元素的摄入量高于化学分析法(P<0.05),称重法调查的平均每天钙、镁、铁、锌、铜、锰摄入量比化学分析法分别高20.9%、67.4%、19.5%、84.4%、46.7%和33.3%;称重法与化学分析法测得的钙、镁、铁、锌、铜、锰摄入量均呈显著正相关(P<0.01),相关系数分别为0.571、0.672、0.521、0.524、0.538和0.691.结论 称重法测得的人群膳食矿物质摄入量高于化学分析法.  相似文献   
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