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   19665篇
  免费   2063篇
  国内免费   466篇
耳鼻咽喉   118篇
儿科学   281篇
妇产科学   400篇
基础医学   1854篇
口腔科学   351篇
临床医学   2075篇
内科学   1667篇
皮肤病学   90篇
神经病学   847篇
特种医学   370篇
外国民族医学   1篇
外科学   6287篇
综合类   2660篇
预防医学   2451篇
眼科学   109篇
药学   1414篇
  26篇
中国医学   516篇
肿瘤学   677篇
  2024年   12篇
  2023年   526篇
  2022年   570篇
  2021年   592篇
  2020年   580篇
  2019年   481篇
  2018年   625篇
  2017年   339篇
  2016年   812篇
  2015年   1167篇
  2014年   1584篇
  2013年   1445篇
  2012年   1208篇
  2011年   1064篇
  2010年   993篇
  2009年   1017篇
  2008年   853篇
  2007年   716篇
  2006年   575篇
  2005年   621篇
  2004年   917篇
  2003年   417篇
  2002年   318篇
  2001年   298篇
  2000年   178篇
  1999年   199篇
  1998年   267篇
  1997年   378篇
  1996年   378篇
  1995年   351篇
  1994年   473篇
  1993年   279篇
  1992年   286篇
  1991年   284篇
  1990年   249篇
  1989年   177篇
  1988年   188篇
  1987年   78篇
  1986年   119篇
  1985年   105篇
  1984年   88篇
  1983年   61篇
  1982年   104篇
  1981年   72篇
  1980年   39篇
  1979年   32篇
  1978年   25篇
  1977年   21篇
  1976年   12篇
  1975年   13篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
目的:探讨建立一种放射治疗全身器官剂量数据库平台的可行性。方法:使用基于深度学习的自动勾画软件DeepViewer?1例食管癌患者的全身CT上勾画全身器官,然后利用基于GPU加速的蒙特卡罗软件ARCHER计算相应的器官剂量分布,最后利用Lyman-Kutcher-Burman(LKB)模型评估放疗患者正常组织并发症概率(NTCP)。结果:针对该病例,成功建立基于DeepViewer?ARCHER和LKB模型的全身器官剂量数据库,发现距离靶区越近的器官剂量越大,其中心脏与靶区间距离最小,剂量为14.11 Gy,但因其模型参数特殊,通过LKB模型计算的NTCP为0.00%;左、右肺的剂量分别为3.19和1.16 Gy,但是NTCP值却很大,分别为2.13%和1.60%。对于距离靶区较远的头颈部器官(视交叉、视神经和眼)和腹部器官(直肠、膀胱和股骨头)剂量分别约为9和2 mGy,并且NTCP均近似为0.00%。结论:研究结果证明通过自动勾画软件DeepViewer?蒙特卡罗软件ARCHER和LKB模型建立全身器官剂量数据库的可行性。  相似文献   
12.
BackgroundSingle-anastomosis duodeno-ileal bypass (SADI) and the one-anastomosis gastric bypass (OAGB) are 2 revisional procedures to address the problem of weight recidivism after laparoscopic sleeve gastrectomy (LSG).ObjectivesTo evaluate the efficacy and safety of SADI and OAGB as revisional bariatric surgery (RBS) in initially super-obese patients (body mass index [BMI] >50 kg/m2).SettingAcademic hospital, bariatric center of excellence, Germany.MethodsObservational study of outcomes in 84 initially super-obese patients who had undergone RBS after LSG (SADI n = 42, OAGB n = 42) between July 2013 and April 2018. Follow-up examinations were performed at 1, 6, 12, 24, and 36 months after RBS. The variables analyzed included time between LSG and RBS, BMI, excess weight loss, total weight loss, operation time, and complications.ResultsThe time interval between LSG and RBS was 45.5 ± 22.8 and 43.5 ± 24.2 months for SADI and OAGB, respectively. At the time of RBS, the mean BMI was 42.8 ± 7.9 kg/m2 for SADI and 43.4 ± 9.2 kg/m2 for OAGB. The follow-up examinations rates (%) after SADI were 97.6, 92.8, 90.5, 78.6, 57.1, and 100, 97.6, 95.2, 85.7, and 59.5 after OAGB. The BMI at the follow-up examinations were 39.1 ± 7.2, 34.2 ± 6.9, 31.2 ± 5.8, 30.2 ± 5.3, 29.3 ± 5.1 for SADI, and 39.5 ± 8.1, 36.6 ± 7.4, 34.7 ± 7.9, 32.9 ± 6.3, and 31.6 ± 5.9 for OAGB. The mean operating times for SADI and OAGB were 138 ± 40 and 123 ± 39 minutes, respectively. Three patients in the SADI group and 1 patient in the OAGB group developed a major complication within the first 30 postoperative days.ConclusionSADI and OAGB were effective second-step procedures for further weight reduction after LSG in initially super-obese patients after short to medium follow-up. There was a trend toward higher weight loss for SADI though this did not reach statistical significance. Substantial differences concerning surgery time and complications between the 2 procedures were not observed.  相似文献   
13.
目的:分析腹腔镜胆囊切除术的临床疗效,分析其对血清应激指标的影响。方法:将160例来我院行胆囊切除术的患者随机分为两组,对照组和观察组各80例。对照组采用开腹胆囊切除术,观察组则采用腹腔镜胆囊切除术。比较两组间手术时间、术中出血量、肠功能恢复时间以及住院天数差异,比较治疗前后两组患者间血清应激相关指标皮质醇(COR)、去甲肾上腺素(NE)、促肾上腺皮质激素(ACTH)、多巴胺(DA)以及胰岛素(INS)、三碘甲状腺原氨酸(T3)、甲状腺素(T4)、促甲状腺激素释放激素(TSH)水平差异。结果:观察组患者手术时间、术中出血量、肠功能恢复时间以及住院天数均显著少于对照组(P<0.05)。血清COR、NE、ACTH、DA和INS、T3水平在围手术期均发生了显著变化,各项指标均在胆囊分离时就明显升高,术后24 h开始下降(P<0.05);术后观察组上述指标均显著低于对照组(P<0.05)。结论:腹腔镜胆囊切除术对机体应激反应影响小于开腹手术,更利于患者术后康复。  相似文献   
14.
15.
16.
目的对比研究腹腔镜下外生性肾血管平滑肌脂肪瘤"蘑菇状"剜除与标准肾部分切除术的安全性及有效性,为肾血管平滑肌脂肪瘤腹腔镜下"蘑菇状"剜除术术式的建立提供临床依据。 方法选取海南医学院第二附属医院与解放军总医院2018年1月至2019年5月期间,接受腹腔镜手术的肾血管平滑肌脂肪瘤患者53例,其中25例沿肿瘤假包膜行"蘑菇状"剜除术(A组)、28例行肾部分切除术(B组)。比较两组手术患者的肾动脉阻断时间、手术时间、术中出血量、术后24 h血红蛋白、术后eGFR(estimated glomerular filtration rate,估计肾小球率过滤)的变化、术后住院时间和术后肿瘤复发率。 结果53例手术无术中转开放,无死亡病例。肾动脉阻断时间:A组(11.9±2.2)min、B组(21.5±6.5) min(P<0.001)。手术时间:A组(87.9±24.8)min、B组(114.3±38.9) min(P<0.001)。术中出血量:A组20 ml(20~40)ml、B组50 ml(50~100)ml(P<0.001)。术后24 h血红蛋白变化:A组(7.4±4.3) g/L、B组(12.4±8.8) g/L(P=0.013)。术后24 h eGFR变化:A组(6.2±7.2 )ml(min·1.73 m2),B组(12.7±12.8)ml(min·1.73 m2)(P=0.027)。术后6个月eGFR变化:A组(1.5±3.7)ml(min·1.73 m2)、B组(6.5±5.6)ml(min·1.73 m2)(P<0.001)。术后住院时间:A组4.0 d(3~4)d、B组4.5 d(3~6)d(P=0.023)。术后随访两组术后肿瘤均无复发。 结论采用腹腔镜"蘑菇状"剜除术治疗外生性肾血管平滑肌脂肪瘤在肾动脉阻断时间、术中出血量、术后24 h血红蛋白、术后eGFR变化、术后住院时间等方面均优于传统肾部分切除术,两组术后肿瘤均无复发;该方法安全、有效,适于临床推广。  相似文献   
17.
《Surgery (Oxford)》2022,40(4):274-276
The spleen is a solid organ located beneath the left hemidiaphragm. Indications for surgical resection include trauma (blunt or penetrating), haematological diseases, abscesses, hydatid disease, oncological resection or immunosuppression. Surgical approaches include open, laparoscopic and, more recently, robotic; the complications of operative intervention will also be discussed. In patients with an absent spleen there is a significant increased risk of developing overwhelming post-splenectomy infection (OPSI). It is therefore essential to protect patients from infection due to encapsulated organisms through vaccination. This requires a combination of vaccinations, antibiotic prophylaxis and good education.  相似文献   
18.
目的介绍腹腔镜下经腹部和后矢状路联合手术治疗直肠肛门手术后复发性直肠尿道瘘和直肠阴道瘘。方法5例术后多次复发性直肠尿道瘘或直肠阴道瘘患儿,男3例,女2例,年龄3~13岁。腹部在腹腔镜下游离结肠,远端尽可能从骶前向盆腔分离肠管,近端肠管游离保证正常结肠能无张力拖至肛门处吻合。低位盆腔肠管分离通过后矢状位切口(肛缘后上1cm),正中切开直肠后壁,直肠内剥离黏膜至齿状线,直视下修补瘘口,近端切断结肠,将正常结肠拖出与肛门吻合。结果所有患儿排便功能良好,仅1例有轻度污粪,未见瘘管复发。结论腹腔镜下经腹部和后矢状路游离结肠、直肠,创伤小,视野清晰,避开了粘连紧密的瘘管分离,完整结肠拖出避免了瘘管的复发,后矢状路直肠切开能直视下显示并修补瘘管。  相似文献   
19.
BACKGROUND: Many mild-to-moderately obese individuals (body mass index [BMI] 30-35 kg/m(2)) have serious diseases related to their obesity. Nonoperative therapy is ineffective in the long term, yet surgery has never been made widely available to this population. METHODS: Between 1996 and 2004, 93 patients with a BMI of 30-35 kg/m(2) underwent laparoscopic adjustable gastric banding with the LAP-BAND. All patients were referred by their primary physician, entered into a comprehensive bariatric surgery program at one Australian center, and operated on by one surgeon. Data on all patients were collected prospectively and entered into an electronic registry. The study parameters included preoperative age, gender, BMI, presence of co-morbidities, percentage of excess weight loss, and resolution of co-morbidities. RESULTS: The mean age was 44.6 years (range 16-76), mean weight was 98 kg, and the mean BMI was 32.7 kg/m(2) (range 30-34). Of the 93 patients, 42 (45%) had co-morbidities, including asthma, diabetes, hypertension, and sleep apnea. The proportion of patients in follow-up was 79%, 85%, and 89% at 1, 2, and 3 years, respectively. The mean weight was reduced to 71 kg at 1 year, 72 kg at 2 years, and 72 kg at 3 years. The mean BMI was reduced to 27.2 +/- 2.2, 27.3 +/- 3.1, and 27.6 +/- 3.7 kg/m(2), respectively, and the mean percentage of excess weight loss was 57.9% +/- 24.5%, 57.6 +/- 29.3%, and 53.8% +/- 32.8% at 1, 2, and 3 years, respectively. At 3 years, the BMI was 18-24 kg/m(2) in 34%, 25-29 kg/m(2) in 51%, and 30-35 kg/m(2) in 10%. At 3 years, the percentage of excess weight loss was <25% in 10%, 25-50% in 24%, 50-75% in 51%, and >75% in 10%. The co-morbidities improved or completely resolved in most patients. No mortality occurred. CONCLUSION: We are very encouraged by this series of low BMI patients treated with the LAP-BAND. Their weight loss has been good, the complications have been minimal, and the co-morbidities have partially or wholly resolved. With additional study, it is reasonable to expect the weight guidelines for bariatric surgery to be altered to include patients with a BMI of 30-35 kg/m(2).  相似文献   
20.
腹腔镜手术时乌司他丁对肝肾功能的保护作用   总被引:16,自引:0,他引:16  
目的观察腹腔镜手术前后肝肾功能的变化,评价应用乌司他丁(UTI)的治疗效果。方法60例择期行腹腔镜手术的患者随机分为两组。U组:UTI治疗组,在手术前和术后第1、2、3天给予UTI20万U静滴;C组给予等量生理盐水静滴。比较两组肝肾功能和促炎性细胞因子的变化。结果两组患者术后第1、3天谷丙转氨酶(ALT)、谷草转氨酶(AST)和血肌酐(Cr)较术前均明显升高(P〈0.05),U组升高程度明显低于C组(P〈0.05),第5天两组ALT、AST和Cr均恢复至术前水平(P〉0.05);术毕、术后第1、3天C组肿瘤坏死因子(TNT-α)、白细胞介素(IL)-6和IL-8较术前显著升高(P〈0.05),术后第5天恢复至术前水平,U组则无明显变化。结论乌司他丁对腹腔镜手术时肝肾功能具有保护作用。  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