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   24931篇
  免费   1293篇
  国内免费   1133篇
耳鼻咽喉   267篇
儿科学   775篇
妇产科学   145篇
基础医学   2036篇
口腔科学   296篇
临床医学   3106篇
内科学   5084篇
皮肤病学   129篇
神经病学   1948篇
特种医学   1179篇
外科学   3470篇
综合类   2957篇
预防医学   1538篇
眼科学   115篇
药学   1605篇
  14篇
中国医学   1710篇
肿瘤学   983篇
  2023年   464篇
  2022年   922篇
  2021年   1287篇
  2020年   1120篇
  2019年   1061篇
  2018年   1023篇
  2017年   885篇
  2016年   872篇
  2015年   880篇
  2014年   1978篇
  2013年   1953篇
  2012年   1565篇
  2011年   1734篇
  2010年   1317篇
  2009年   1232篇
  2008年   1309篇
  2007年   1176篇
  2006年   1035篇
  2005年   858篇
  2004年   633篇
  2003年   508篇
  2002年   382篇
  2001年   345篇
  2000年   303篇
  1999年   271篇
  1998年   190篇
  1997年   185篇
  1996年   134篇
  1995年   127篇
  1994年   104篇
  1993年   117篇
  1992年   91篇
  1991年   77篇
  1990年   90篇
  1989年   76篇
  1988年   59篇
  1987年   44篇
  1986年   53篇
  1985年   99篇
  1984年   108篇
  1983年   81篇
  1982年   88篇
  1981年   104篇
  1980年   67篇
  1979年   59篇
  1978年   65篇
  1977年   49篇
  1976年   47篇
  1975年   31篇
  1973年   30篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
目的探讨便秘术后胃排空功能障碍(FDGE)的原因及肠内营养支持治疗的作用。方法回顾性分析2008年7月至2013年3月80例重度功能性便秘患者的临床资料,患者行结肠次全切除联合改良Duhamel术,术后发生FDGE者进行肠内营养支持等保守治疗。结果80例重度功能性便秘患者术后有13例发生FDGE,发生率为16.25%,其中9例耐受全肠内营养治疗,4例辅助外周静脉营养支持。保守治疗后7~43d后好转。结论功能性消化不良可能是便秘患者术后发生胃排空功能障碍的主要原因,肠内营养支持在治疗胃排空功能障碍中起主要作用。  相似文献   
992.
目的:加强对布鲁杆菌病的认识,为早期诊断及防止误诊提供依据。方法采用回顾性方法分析57例布鲁杆菌病患者的流行病学特征及临床资料。结果发病人群主要为男性、农牧民。感染途径主要为接触或食用感染布鲁杆菌的动物。地区主要分布于农牧区,有向城市蔓延趋势;发病率有升高趋势。临床表现主以发热(71.92%)、乏力(66.67%)、关节疼痛(66.67%)、淋巴结肿大(29.82%)及贫血(19.30%)为主,实验室检查白细胞计数下降者占12.28%,血小板下降者占8.71%),血沉、血清免疫球蛋白及ALT升高者分别占61.40%、42.11%及29.82%。按照WHO相关建议规范治疗后,患者预后较好。结论布鲁杆菌病临床表现复杂,临床医师应加强对其认识,防止误诊;加强人畜的防疫工作十分重要。  相似文献   
993.
目的报道完全腹腔镜下Roux—en—Y吻合术的手术方法,探讨腹腔镜下Roux—en—Y吻合术在胆系疾病手术中的应用价值。方法对103例患者行完全腹腔镜下胆肠Roux—en—Y吻合术,其中多次手术取石后,胆总管结石再发合并胆管狭窄28例,医源性胆道损伤3例,胆总管囊肿24例,肝门部胆管癌36例,胰头癌及壶腹癌12例。所有手术均采用5个Trocar进行操作。首先在腹腔镜下处理胆道病变,即切开胆总管、取净结石;修整并切开损伤胆总管;切除扩张的胆总管;切除肿瘤部位胆管或者纵行切开恶性黄疸患者胆总管引流等;同时为胆肠吻合前做好肝管断端的准备。然后更换腹腔镜位置,于镜下切断空肠及其系膜,行空肠间侧侧吻合。将腹腔镜位置复位,镜下将Roux—en—Y胆支空肠襻牵拉至肝门处行胆肠侧侧或者端侧吻合。最后留置腹腔引流管。结果全组病例均成功完成手术,残余胆(肝)管直径0.4~3.2锄,平均0.9Gin。术后胆汁漏3例,经腹腔引流1周~1个月治愈。2例胆道损伤伴阻塞性黄疸患者,术后均出现应激性溃疡及腹腔内出血,1例腹腔内出血经再次腹腔镜手术止血治愈,另1例经腹腔引流、抑酸及止血药物治疗2d后治愈。95例患者获随访,随访率92.2%(95/103),随访时间4~93个月,平均48-3个月。胰头、壶腹癌及上段胆管癌患者,随访期间14个月内因转移及消耗死亡,均无手术并发症发生;3例胆总管结石患者分别于术后2、3、5年发生反流性胆管炎,来院经抗炎对症治疗后痊愈出院;其余患者随访期间均无胆道、胆肠吻合口狭窄等并发症发生。结论完全腹腔镜下胆肠Roux—en—Y吻合术是胆道疾病需行胆肠吻合手术治疗的最佳、首选术式,但术者需具有丰富的腹腔镜手术经验。  相似文献   
994.
995.
Mesenchymal tumors involve the gastrointestinal (GI) tract more frequently than other visceral organs. Many such tumors are small, and are benign and increasingly being detected incidentally during colonoscopic screening. Some tumors show distinctive features at this site, such as schwannoma and clear cell sarcoma–like tumor of the GI tract. Without knowledge of these features, recognition of these tumor types can be difficult. This reviews addresses recent developments and diagnostic features of mesenchymal tumors of the GI tract other than gastrointestinal stromal tumor (GIST).  相似文献   
996.
The Carney triad (CT) describes the coexistence of multiple neoplasms including gastrointestinal stromal tumors (GISTs), extra-adrenal paraganglioma and pulmonary chondroma. At least two neoplastic tumors are required for diagnosis. In most cases, however, CT is incomplete. We report a case of an incomplete CT in a 34-year-old woman with a multifocal GIST and non-functional paraganglioma of the liver. Preoperative evaluation with a gastrofiberscope and abdominal computed tomography revealed multiple gastric tumors resembling GISTs and a single liver lesion which was assumed to have metastasized from the gastric tumors. The patient underwent total gastrectomy and partial hepatectomy. Histologic findings confirmed multiple gastric GISTs and paraganglioma of the liver. We report a case of a patient with incomplete expression of CT.  相似文献   
997.
INTRODUCTIONDiscovery of abdominal masses often poses significant diagnostic difficulties. GISTs are mesenchymal masses, with specific histological features. Dimensions may vary from millimeters to giant tumours. We would like to present our case, which had an unexpectedly easy operative course which was easily handled with a simple surgical excision with a short operative duration.PRESENTATION OF CASEA 38 years old female patient was diagnosed to have an abdominal heterogen mass of 15 cm × 12 cm × 10 cm in dimension. Abdominal computed tomography revealed the solid mass between the stomach and pancreas corpus and tail, possibly orginating from the pancreas. With the preoperative diagnosis of locally invasive distal pancreas cancer the patient underwent laparotomy, following the dissection, the mass was observed to be originating from the posterior gastric Wall, extending exophytically with a peduncle of 5 cm in width, without any visual evidence for peritoneal invasion and metastasis. The tumour and the peduncle was resected with stapler device. Total operation time was 30 min. Postoperative course was uneventful. Pathologic diagnosis was gastrointestinal stromal tumour (GIST).DISCUSSIONPedunculated large GISTs are not frequent and they can enlarge as 15 cm in diameter and compress the neighbouring organs. When they were huge, it is difficult to differentiate the origin of the masses. GISTs should be considered in differential diagnosis of giant abdominal masses.CONCLUSIONWhen GISTs are huge and pedunculated, it can be difficult to differentiate the origin of the masses. This case report presents unexpectedly ease surgery for a worrysome abdominal mass.  相似文献   
998.
INTRODUCTIONEnteropathy-associated T-cell lymphoma (EATL) is a very rare malignancy. Reasons for hospital admission are variable.PRESENTATION OF CASE76 years old man admitted to emergency service with sudden and massive obscure gastrointestinal bleeding. There was no complaints in his history. After initial evaluation, emergency laparatomy had to be done. Bleeding lesion in proximal jejunum was resected. Histopathologically, the muscularis propria had abundant atypical lymphoid infiltrate in diffuse pattern. Atypical lymphoid cells expressed CD3 and CD30. The jejunal mucosa adjacent to the tumor showed effacement of normal villous architecture.DISCUSSIONEATL is known to cause anemia as a result of chronic bleeding. However in this case, the bleeding was abundant, irreplaceable and requiring emergency surgery. To our knowledge it is not reported previously.CONCLUSIONA sudden and massive gastrointestinal bleeding can be the first and unique sign of EATL.  相似文献   
999.
Many features of posttraumatic stress disorder (PTSD) can be linked to exaggerated and dysregulated emotional responses. Central to the neurocircuitry regulating emotion are functional interactions between the amygdala and the ventromedial prefrontal cortex (vmPFC). Findings from human and animal studies suggest that disruption of this circuit predicts individual differences in emotion regulation. However, only a few studies have examined amygdala-vmPFC connectivity in the context of emotional processing in PTSD. The aim of the present research was to investigate the hypothesis that PTSD is associated with disrupted functional connectivity of the amygdala and vmPFC in response to emotional stimuli, extending previous findings by demonstrating such links in an understudied, highly traumatized, civilian population. 40 African-American women with civilian trauma (20 with PTSD and 20 non-PTSD controls) were recruited from a large urban hospital. Participants viewed fearful and neutral face stimuli during functional magnetic resonance imaging (fMRI). Relative to controls, participants with PTSD showed an increased right amygdala response to fearful stimuli (pcorr < .05). Right amygdala activation correlated positively with the severity of hyperarousal symptoms in the PTSD group. Participants with PTSD showed decreased functional connectivity between the right amygdala and left vmPFC (pcorr < .05). The findings are consistent with previous findings showing PTSD is associated with an exaggerated response of amygdala-mediated emotional arousal systems. This is the first study to show that the amygdala response may be accompanied by disruption of an amygdala-vmPFC functional circuit that is hypothesized to be involved in prefrontal cortical regulation of amygdala responsivity.  相似文献   
1000.
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