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   263444篇
  免费   24866篇
  国内免费   17764篇
耳鼻咽喉   2442篇
儿科学   3559篇
妇产科学   1612篇
基础医学   20210篇
口腔科学   4603篇
临床医学   32978篇
内科学   27705篇
皮肤病学   2465篇
神经病学   8652篇
特种医学   10783篇
外国民族医学   66篇
外科学   25596篇
综合类   65190篇
现状与发展   63篇
一般理论   8篇
预防医学   27187篇
眼科学   4349篇
药学   30868篇
  330篇
中国医学   22288篇
肿瘤学   15120篇
  2024年   1106篇
  2023年   3367篇
  2022年   8604篇
  2021年   10674篇
  2020年   9160篇
  2019年   6158篇
  2018年   6445篇
  2017年   7496篇
  2016年   6293篇
  2015年   10714篇
  2014年   13568篇
  2013年   15449篇
  2012年   22360篇
  2011年   24004篇
  2010年   20164篇
  2009年   17719篇
  2008年   19089篇
  2007年   18580篇
  2006年   16946篇
  2005年   13911篇
  2004年   10604篇
  2003年   9981篇
  2002年   8138篇
  2001年   7111篇
  2000年   5433篇
  1999年   3124篇
  1998年   1651篇
  1997年   1526篇
  1996年   1151篇
  1995年   1083篇
  1994年   972篇
  1993年   533篇
  1992年   580篇
  1991年   492篇
  1990年   400篇
  1989年   374篇
  1988年   274篇
  1987年   236篇
  1986年   196篇
  1985年   134篇
  1984年   74篇
  1983年   54篇
  1982年   61篇
  1981年   33篇
  1980年   20篇
  1979年   17篇
  1978年   2篇
  1965年   4篇
  1964年   2篇
  1962年   2篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
目的 分析重庆市肺癌发病死亡和疾病负担归因于被动吸烟的情况,为开展肺癌防治提供建议。 方法 肺癌死亡个案数据来源于2019年重庆市肿瘤登记报告系统,被动吸烟率来自2013年重庆市慢性病及危险因素监测。计算人群归因危险度百分比(population attributable risk percent, PAR%)、被动吸烟导致的肺癌发病、死亡和疾病负担。采用Excel 2010与SPSS 25.0进行统计分析,率的比较采用χ2检验。 结果 2013年30岁及以上成年人被动吸烟率为52.37%。2019年重庆市30岁及以上人群肺癌发病率与标化发病率分别为118.44/10万与80.83/10万,死亡率与标化死亡率分别为96.51/10万、63.58/10万。肺癌发病率和死亡率归因于被动吸烟的PAR%分别为19.76和19.04,归因发病率与归因标化发病率分别为23.41/10万和16.34/10万,归因死亡率与归因标化死亡率分别为18.38/10万和12.40/10万。2019年重庆市30岁及以上肺癌早死所致寿命损失年率(years of life lost,YLL)、残疾所致寿命损失年率(years lived with disability,YLD)、调整伤残寿命损失年率(disability adjusted life year,DALY)分别为21.16‰、0.31‰、21.47‰,YLL率、YLD率、DALY率归因于被动吸烟的PAR%分别为21.16、19.76和20.49,归因YLL率为4.34‰,归因YLD率为0.06‰,归因DALY率为4.40‰。 结论 2019年重庆市30岁及以上人群肺癌发病率、死亡率、YLL率、DALY率高,被动吸烟率高,肺癌归因于被动吸烟的疾病负担重,应加强落实控烟工作。  相似文献   
2.
目的通过研究肺表面活性物质(PS)结合持续气道正压通气(CPAP)治疗新生儿呼吸窘迫综合征(NRDS)的治疗效果,进一步指导NRDS的临床治疗。方法选取于2017年4月-2018年10月间在本院收治的80例确诊为新生儿呼吸窘迫综合征的患儿作为研究对象,随机将患儿分为试验组和对照组,对照组给予持续气道正压通气治疗,试验组在对照组的基础上联合使用PS治疗。结果试验组对于呼吸窘迫缓解的有效率明显高于对照组,在气管插管内滴入PS治疗后试验组的血气情况明显优于对照组,且试验组患儿副作用发生率明显低于对照组,以上指标差异具有统计学意义,P <0.05。结论 PS结合CPAP在新生儿呼吸窘迫综合征的治疗中疗效很好。  相似文献   
3.
We report clinical, neuroradiologic features, and neuropathologic findings of a 76‐year‐old man with coexistent Pick’s disease and progressive supranuclear palsy. The patient presented with loss of recent memory, abnormal behavior and change in personality at the age of 60. The symptoms were progressive. Three years later, repetitive or compulsive behavior became prominent. About 9 years after onset, he had difficulty moving and became bed‐ridden because of a fracture of his left leg. His condition gradually deteriorated and he developed mutism and became vegetative. The patient died from pneumonia 16 years after the onset of symptoms. Serial MRI scans showed progressive cortex atrophy, especially in the bilateral frontal and temporal lobes. Macroscopic inspection showed severe atrophy of the whole brain, including cerebrum, brainstem and cerebellum. Microscopic observations showed extensive superficial spongiosis and severe neuronal loss with gliosis in the second and third cortical layers in the frontal, temporal and parietal cortex. There were Pick cells and argyrophilic Pick bodies, which were tau‐ and ubiquitin‐positive in neurons of layers II–III of the above‐mentioned cortex. Numerous argyrophilic Pick bodies were observed in the hippocampus, especially in the dentate fascia. In addition, moderate to severe loss of neurons was found with gliosis and a lot of Gallyas/tau‐positive globus neurofibrillary tangles in the caudate nucleus, globus pallidus, thalamus, substantia nigra, locus coeruleus and dentate nucleus. Numerous thorned‐astrocytes and coiled bodies but no‐tuft shaped astrocytes were noted in the basal ganglion, brainstem and cerebellar white matter. In conclusion, these histopathological features were compatible with classical Pick’s disease and coexistence with progressive supranuclear palsy without tuft‐shaped astrocytes.  相似文献   
4.
Cardiac myxoma has varying clinical presentation, uncertain histogenesis and debatable immunohis- tochemical profile. Glandular epithelial differentiation is a rare phenomenon, but glandular elements are known to be present in cardiac myxoma as an intrinsic component of the tumor. We present a case of cardiac myxoma having focal glandular differentiation, with special reference to the morphologic features and immunohistochemical profiles.  相似文献   
5.
目的观察亚甲蓝甘油合剂封闭治疗三叉神经痛的临床疗效并探讨其治疗机制。方法按国际头面痛学会分类委员会确定的诊断标准,108例原发性三叉神经患者随机分为两组:A组为亚甲蓝甘油合剂组(n=54),B组为单纯甘油合剂组(n=54);采用徐贵印推荐的三维测角穿刺半月神经节进行封闭治疗,对治疗后1周、3个月和2年分别进行疗效评判和随访观察。结果两组治疗后1周、3个月优良率比较差异无统计学意义(P>0.05),两年后优良率比较差异有统计学意义(P<0.05);两组并发症没有明显差异,2例出现视力下降,3例因解剖变异未能穿刺成功,仅在卵圆孔周围进行了注射,外加眶下孔以及骸孔封闭。结论亚甲蓝甘油合剂用于治疗三叉神经痛远期疗效优于单纯甘油合剂,且亚甲蓝对神经未见明显损害(经2年随访)。  相似文献   
6.
Acupuncture analgesia (AA) caused by low frequency stimulation of the acupuncture point (AP) was abolished by hypophysectomy and adrenalectomy. Termination of the AA producing pathway from the AP to the pituitary gland was in the medial hypothalamic arcuate nucleus (M-HARN). The origin of the descending pain inhibitory system associated with AA was in the posterior HARN (P-HARN). AA in the hypophysectomized rats, and enhanced neuronal activity in the P-HARN that were abolished during acupuncture stimulation, were both restored by intraperitoneal microinjection of 0.5 mg/kg morphine or 0.1 micrograms beta-endorphin into the P-HARN during acupuncture stimulation. Of the analgesia produced by dopamine or beta-endorphin injected into the P-HARN, that caused by beta-endorphin disappeared after denervation of the M-HARN. The P-HARN neurons that responded to acupuncture stimulation also responded to iontophoretic dopamine, but not to iontophoretic morphine nor ultramicroinjected beta-endorphin. The transmission between the M-HARN and P-HARN may be dopaminergic, and beta-endorphin might presynaptically modulate this transmission. Reduction of sodium ions may have been the reason for abolition of AA after adrenalectomy.  相似文献   
7.
Q Guo  Z Guo 《中西医结合杂志》1989,9(8):472-4, 452
The effect of the traditional Chinese medicinal herbs enema and enteric-coated capsules in the treatment of ulcerative colitis (UC) were compared in 260 cases. The immune complexes and the dynamic change of autoantibodies were monitored in 28 out of the 260 cases before and after treatment. The following results were observed. (1) There was no significant difference in the total effective rate between the enema group and the oral capsule group (93.3% and 87.5% respectively), but the recovery rates of purulent hemafecia, mucusfecia and erosion accompanying colitis, etc. in the former group were higher than those in the latter (P less than 0.01). (2) The circulating immune complexes were found 43 times above the normal range in 17 cases with positive rate 60.7%, and tended to decrease as the condition became better after treatment. Antinuclear antibodies were determined by the indirect fluorescent immune method and the indirect enzyme labelling method and the positive rates were 53.6% and 64.7% respectively, both being much higher than those in the controls (P less than 0.01).  相似文献   
8.
目的总结和探讨脑血管造影和载瘤动脉闭塞在治疗颅内巨大动脉瘤上的作用及特点。方法60例颅内巨大动脉瘤患者,根据其脑血管造影的特点采取血管内介入方法[可脱式球囊和(或)弹簧圈]闭塞载瘤动脉近端53例、闭塞载瘤动脉两端后孤立动脉瘤7例;其中23例闭塞前先行颅内-外血管搭桥术。结果出院时Rankin评分分级:单纯血管内介入治疗组37例中轻残3例,合并颅内-外血管搭桥术组23例中死亡1例、重残2例。1-6年的影像学随访动脉瘤无复发。结论血管内介入结合颅内-外血管搭桥术闭塞载瘤动脉是治疗颅内巨大动脉瘤的方法之一。  相似文献   
9.
10.
目的:探讨新生儿腹胀的常见原因及治疗、转归。方法:对98例腹胀新生儿进行病因分类、回顾性分析治疗转归。结果:以出院诊断为标准,98例患儿中感染性疾病42例,占42.86%;早产儿生活力低下32例,占32.65%。1~3d痊愈12例,1W内痊愈81例,3例转外科治疗,2例死亡。结论:感染性疾病是新生儿腹胀的主要原因,早产儿尤其体重低下者是腹胀的高危人群。临床医师应高度重视,尽快明确原因,给予及时、合理治疗,以提高新生儿生存率。  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