全文获取类型
收费全文 | 18996篇 |
免费 | 1414篇 |
国内免费 | 322篇 |
专业分类
耳鼻咽喉 | 131篇 |
儿科学 | 254篇 |
妇产科学 | 200篇 |
基础医学 | 1164篇 |
口腔科学 | 635篇 |
临床医学 | 2526篇 |
内科学 | 1430篇 |
皮肤病学 | 137篇 |
神经病学 | 617篇 |
特种医学 | 1520篇 |
外国民族医学 | 11篇 |
外科学 | 2683篇 |
综合类 | 3728篇 |
一般理论 | 1篇 |
预防医学 | 2208篇 |
眼科学 | 266篇 |
药学 | 1131篇 |
66篇 | |
中国医学 | 402篇 |
肿瘤学 | 1622篇 |
出版年
2024年 | 44篇 |
2023年 | 372篇 |
2022年 | 590篇 |
2021年 | 805篇 |
2020年 | 820篇 |
2019年 | 555篇 |
2018年 | 554篇 |
2017年 | 584篇 |
2016年 | 662篇 |
2015年 | 688篇 |
2014年 | 1418篇 |
2013年 | 1273篇 |
2012年 | 1273篇 |
2011年 | 1336篇 |
2010年 | 1042篇 |
2009年 | 1059篇 |
2008年 | 931篇 |
2007年 | 941篇 |
2006年 | 859篇 |
2005年 | 726篇 |
2004年 | 585篇 |
2003年 | 516篇 |
2002年 | 364篇 |
2001年 | 296篇 |
2000年 | 260篇 |
1999年 | 271篇 |
1998年 | 213篇 |
1997年 | 216篇 |
1996年 | 163篇 |
1995年 | 161篇 |
1994年 | 139篇 |
1993年 | 126篇 |
1992年 | 104篇 |
1991年 | 91篇 |
1990年 | 70篇 |
1989年 | 68篇 |
1988年 | 67篇 |
1987年 | 56篇 |
1986年 | 50篇 |
1985年 | 76篇 |
1984年 | 46篇 |
1983年 | 42篇 |
1982年 | 54篇 |
1981年 | 30篇 |
1980年 | 20篇 |
1979年 | 27篇 |
1978年 | 19篇 |
1977年 | 20篇 |
1976年 | 14篇 |
1973年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 409 毫秒
51.
OBJECTIVE: Many patients with haemorrhoids are investigated because of the fear of missing colorectal cancer (CRC). The aim of this study was to determine whether a primarily clinical approach regarding the need for investigation was safe and did not miss patients with CRC. PATIENTS AND METHODS: Data was collected prospectively on 589 consecutive patients with the principle diagnosis of haemorrhoids at first clinic visit. All had clinical assessment including rigid sigmoidoscopy and were treated by phenol injection or banding. They were categorized for (1) no review unless symptoms persisted -'One Stop SOS' (2) outpatient review or (3) investigation. To check for the development of CRC they were contacted by postal questionnaire or telephone interview with a minimum of one year from diagnosis and treatment. All 589 patients were cross-referenced with the Pathology database and the Hospital Information Services System. RESULTS: Four hundred and sixty-nine (80%) answered the questionnaire; 352 patients (60% of the total group) fell in the 'one stop SOS' outpatient category; 95 (16%) patients were followed up to review response to treatment for large haemorrhoids; 105 (18%) were investigated with barium enema (12%), flexible sigmoidoscopy (4%), colonoscopy (1%) and miscellaneous (1%); 37 (6%) patients were either given a haemorrhoidectomy date or referred on with a different diagnosis. No patients selected for 'one-stop' treatment developed CRC. Five (0.8%) patients were diagnosed with CRC after appropriate investigation was instituted for suspicious symptoms. One patient with distal transverse colon cancer had a delayed diagnosis as she was investigated initially by flexible sigmoidoscopy. CONCLUSION: Most patients with the primary diagnosis of symptomatic haemorrhoids do not need investigation. 相似文献
52.
C. V. Dalchow A. L. Weber S. Bien N. Yanagihara J. A. Werner 《European archives of oto-rhino-laryngology》2006,263(2):92-99
Digital volume tomography (DVT) is an extension of panoramic tomography. With this diagnostic technique, characterized by high resolution, a narrow section width (0.125 mm) and three-dimensional display, small pathological processes can be well visualized. Twenty-five patients with the history of a progressive hearing loss were examined with DVT (Accu-I-tomo, Morita, Japan). The results were compared with pre- and intraoperative findings to evaluate the diagnostic value of DVT in cases of erosion of the ossicular chain. With high resolution and artifact-free demonstration of the middle ear and the ossicular chain, it was possible to define its continuity preoperatively by DVT in all 25 cases. An intact ossicular chain was found by DVT in 13 cases and was later confirmed by surgery. The predicted erosion of the ossicles was verified in 12 patients, and a tympanoplasty type III was performed. Digital volume tomography is an excellent technique to examine the middle ear cleft and inner ear, and expands the application of diagnostic possibilities in the lateral skull base. Therefore, improvement in preoperative diagnosis is achieved along with more accurate planning of the surgical procedure. Digital volume tomography delivers a small radiation dose with a high resolution and a low purchase price for the equipment. 相似文献
53.
An adaptor to the Leksell stereotaxic instrument for digital coordinate determination in radiography
Summary Special perspex adaptors with radiopaque reference structures have been constructed to fit to the Leksell stereotaxic instrument. These structures are visualized on X-ray film in a radiographic examination like angiography or encephalography. The films obtained in two projections at arbitrary angles and focus-film-distances are placed on a digitizing table for the determination of the stereotaxic coordinates of selected targets. The reference structures and the targets are marked with a cursor whereupon a desk top computer performs the calculation of the stereotaxic coordinates. The system allows a rapid, simple and accurate coordinate determination in stereotaxic radiography using the Leksell stereotaxic instrument. 相似文献
54.
55.
目的:探讨儿童在X线体检中减少照射剂量的方法。方法:应用东芝500mA遥控X线机、FJ-427型热释光剂量仪等设备,对100名3~5岁儿童体检时,随机分成两个对照组、每组50名,分别接受胸透或平片检查,对检查测得数据均进行统计学处理。结果:胸透时胸部接受的照射剂量是平片的22倍多,其它部位接受的X线散射剂量平均值之比亦在20~30倍之间。结论:在儿童X线体检中应采用常规胸片替代胸透,可以有效地降低其辐射危害。 相似文献
56.
歼击机飞行员改装体检脊柱病症的医学鉴定 总被引:6,自引:1,他引:5
目的对近几年来我院改装体检歼击机飞行员脊柱病症健康鉴定进行归纳总结。方法收集分析了261例歼击机飞行员体检和X线、CT的影像诊断资料,并对因脊柱病症体检不合格资料进行统计学分析。结果歼击机飞行员体检中,脊柱影像诊断中以腰椎间盘突出(49例)最多,但多数没有相应的临床症状,有20例因脊柱病症不合格,其中腰椎双侧峡部裂伴Ⅰ°滑脱9例,占不合格总数的45%,是不合格的主要原因。结论外科体检中应该重点加强对脊柱的检查,影像诊断应结合症状和脊柱功能作出鉴定,必要时应作随访观察。 相似文献
57.
目的:运用ROC曲线,探讨DR胸部摄影最佳的影像后处理技术。方法:使用DR系统设置的正常胸部摄影条件,对胸部体模与专用于X线摄影的ROC曲线评价体模(TRG)进行组合并曝光。分析未使用后处理技术及使用不同后处理技术,对DR胸部摄影胸片影像的影响。结果:使用单纯噪声消除技术、噪声消除加图像反转及噪声消除加全屏放大三种后处理技术所得的ROC曲线下面积Az值依次为0.85、0.825及0.925,均明显大于未使用后处理技术的面积Az值0.6;单纯噪声消除技术获得的ROC曲线下面积略大于噪声消除加图像反转技术的面积;噪声消除加全屏放大技术获得的ROC曲线下面积Az值最大。结论:应对胸部原始影像实施后处理调节。单纯噪声消除技术可明显增加影像的信息量,若在噪声消除基础上实施全屏放大技术,可获得DR胸部摄影的最大影像信息量。 相似文献
58.
氯氮平对51例精神病患者骨髓象的影响 总被引:1,自引:1,他引:0
精神病女性患者51例,服用氯氮平100-350mg/d,共42d。22例骨髓象由用药前的增生活跃变为增生明显活跃,骨髓粒细胞系统所占比例明显增多;29例无变化。未见骨髓抑制者。 相似文献
59.
A. Satish Chandra Sanjeev Mohanty 《Indian journal of otolaryngology and head and neck surgery》2007,59(1):43-44
Role of Embolisation in preoperative management of Nasopharyngeal angiofibroma is well established in present day therapeutic
modalities. An improvised technique i.e., subselective embolisation has been provided by Interventional radiologists to fortify
the therapeutic results. This study compares the final outcome of seven cases, four of which were embolised pre operatively.
Each case was dealt with varying surgical approaches. 相似文献
60.
目的:了解严重急性呼吸综合征(SARS)死亡病例的临床特点,为SARS重症病例的诊断、治疗及预后判断提供帮助。方法:对我院2003年1月至4月底收治的102例确诊非典患者中的5例死亡病例的流行病学及实验室检查资料进行回顾性分析。结果:死亡病例均为男性,平均49岁,从发病到入院平均7.6d,从住院到确诊平均1.2d;从住院到死亡平均14.4d,从发病到死亡平均为22d。死亡病例粒细胞总数和百分比均明显升高,多数患者淋巴细胞计数和百分比降低(4/5),血红蛋白均呈进行性下降。死亡患者除已见报道的ALT、AST、LDH、CK升高及低钙血症外,GLU均明显高于正常而ALB均明显降低;大多数患者TP、PA等多项生化指标均出现明显下降而脱氧血红蛋白百分率(HHb)明显上升,同时伴有低磷、低镁血症。结论:SARS死亡病例多项实验室指标均会出现明显异常,动态监测这些指标有助于SARS患者的诊断、治疗及预后判断。 相似文献