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   92913篇
  免费   8871篇
  国内免费   4434篇
耳鼻咽喉   690篇
儿科学   1847篇
妇产科学   766篇
基础医学   7065篇
口腔科学   1871篇
临床医学   11115篇
内科学   10319篇
皮肤病学   913篇
神经病学   3374篇
特种医学   3423篇
外国民族医学   3篇
外科学   9129篇
综合类   20968篇
现状与发展   22篇
一般理论   7篇
预防医学   10975篇
眼科学   1565篇
药学   10372篇
  88篇
中国医学   7153篇
肿瘤学   4553篇
  2024年   397篇
  2023年   1083篇
  2022年   2471篇
  2021年   3243篇
  2020年   2779篇
  2019年   1653篇
  2018年   1794篇
  2017年   2274篇
  2016年   1826篇
  2015年   3226篇
  2014年   4201篇
  2013年   5411篇
  2012年   7535篇
  2011年   8008篇
  2010年   7309篇
  2009年   6545篇
  2008年   6909篇
  2007年   6782篇
  2006年   5936篇
  2005年   4818篇
  2004年   3644篇
  2003年   3033篇
  2002年   2519篇
  2001年   2183篇
  2000年   1833篇
  1999年   911篇
  1998年   303篇
  1997年   261篇
  1996年   239篇
  1995年   237篇
  1994年   211篇
  1993年   183篇
  1992年   461篇
  1991年   435篇
  1990年   424篇
  1989年   361篇
  1988年   359篇
  1987年   355篇
  1986年   356篇
  1985年   315篇
  1984年   270篇
  1983年   237篇
  1982年   169篇
  1981年   157篇
  1979年   220篇
  1978年   188篇
  1976年   140篇
  1975年   140篇
  1974年   166篇
  1973年   163篇
排序方式: 共有10000条查询结果,搜索用时 8 毫秒
61.
目的观察杨辣子昆虫系列药对类风湿性关节炎(RA)主要临床症状的疗效。方法采用具备独立发明专利权的杨辣子昆虫系列药(专利号9112102.7)针剂皮下肌肉阿是穴注射,口服其药酒和胶丸。结果经过3个月治疗后,RA主要症状休息痛、晨僵、关节肿胀和关节压痛有明显改善(P〈0.05),关节畸形部分改善。治疗前后总分比较临床有效率为93.75%。结论杨辣子昆虫系列药治疗RA的主要症状有较好疗效。  相似文献   
62.
Objective To observe the effect of intrathecal clonidine plus morphine on expression of protein kinase A (PKA) catalytic subunit in the spinal dorsal horn in a rat model of incisional pain. Methods Eighty male Sprague-Dawley rats were divided randomly into five groups: sham group, control group, pre-incisional morphine 2.5 μg group, pro-incisional clonidine 5 μg group and preincisional morphine 2.5 μg plus clonidine 5 lag group (n=16). lntrathecal catheter and the model of incisional pain were pro-duced according to Yaksh and Brennan's described method respectively. Changes of pain behavior were assessed by mechanical with-drawal threshold (MWT) and thermal withdrawal latency(TWL). The expressions of PKA catalytic subunit in the spinal dorsal horn were assessed by immunohistochemical method and western blotting analysis. Results Compared with sham group, MWT and TWL in control group were decreased significantly at 2 h after incision (P<0.01) and the number of positive cells and protein expression of PKA catalytic subunit in the spinal dorsal horn were increased significantly in control group (P<0.01). Compared with control group, MWT and TWL in pre-incision morphine 2 μg plus clonidine 5 lag group were increased significantly at 2 h after incision (P<0.01) and the number of positive cells and protein expression of PKA catalytic subunit in the spinal dorsal horn were decreased significantly in pre-incision morphine 2 μg plus clonidine 5 μg group (P<0.01). However, MWT, TWL and the number of positive cells and pro-tein expression of PKA catalytic subunit in the spinal dorsal horn changed with no statistical significance in pre-incisional morphine 2.5 μg group and pre-incisional clonidine 5 μg group compared with control group. Conclusion lntrathecal clonidine significantly enhances the antinociceptive effect of intrathecal morphine in a rat model of incisional pain, which might be associated with inhibi-tion of the increased expression of PKA catalytic subunit in spinal cord.  相似文献   
63.
目的利用MR显微成像技术研究阿尔茨海默病转基因小鼠老年斑的沉积情况。方法2只17个月龄阿尔茨海默病转基因[V717I]小鼠和2只野生型小鼠,行活体T2WI,然后对照影像定位结果进行组织学切片及免疫组织化学染色。观察T2WI中老年斑的沉积情况以及其与免疫组织化学染色结果的对应关系。结果转基因小鼠T2WI上显示大脑皮层和海马区可见点状低信号,且部分低信号可以和组织学切片所显示的老年斑相对应;野生型小鼠T2WI未见明显的低信号,免疫组织化学染色也未见到染色阳性的斑块。结论MR显微成像技术检测老年斑的沉积是可行的,且可用来特异性地诊断阿尔茨海默病。  相似文献   
64.
65.
Coupling intervals of premature ventricular beats and complex arrhythmias were studied by 24-h ambulatory electrocardiographic recordings in 76 patients (35 sudden death patients and 41 survivors) with coronary artery disease. A first Holter (HM 1) was recorded at the time of left ventricular angiography and a second Holter (HM 2) after a mean interval of 34.4 +/- 11.2 months (range 2-61 months). All patients were only treated medically. The mean heart rate was significantly faster in patients who died suddenly than in survivors in both HM 1 and HM 2 (p less than 0.01). In HM 1, there were no significant differences in mean coupling intervals between patients who died suddenly and survivors, whereas in HM 2, coupling intervals of premature ventricular beats and couplets were significantly shorter in patients who died suddenly than in survivors (p less than 0.05). Patients with coupling intervals for couplets less than 500 ms died significantly earlier than those patients with coupling intervals greater than 500 ms (p less than 0.05). Our data show that there is a relationship between heart rate, coupling intervals and sudden death. Patients with fast heart rates and coupling intervals for couplets less than 500 ms represent a group at high risk of sudden death.  相似文献   
66.
Tuberculosis involving the soft tissue from adjacent bone or joint is well recognized. However, primary tuberculous pyomyositis, tuberculous bursitis, and tuberculous tenosynovitis are rare entities constituting 1% of skeletal tuberculosis. Tuberculous tenosynovitis involves most commonly the tendon sheaths of the hand and wrist, and tuberculous bursitis occurs most commonly around the hip. The greater trochanteric bursa and the greater trochanter are the most frequent sites of tuberculous bursitis. Cases of primary tuberculous pyomyositis and tenosynovitis of the tendons of the ankle and foot are seldom reported in the radiology literature. All imaging modalities-plain radiography, bone scan, computed tomography, and magnetic resonance imaging (MRI)--provide information that is helpful in determining therapy. MRI in particular, with its multiplanar capabilities and superb contrast of soft tissue, can demonstrate the extent of the soft tissue mass and access the adjacent bones and joints. However, MRI has no diagnostic specificity in regard to tuberculosis, and in nonendemic areas, biopsy is strongly recommended. All patients in this review were permanent residents of North America or Western Europe and were immunocompetent. Examples of atypical presentations of the above entities are demonstrated.  相似文献   
67.
对宿主易感性的认识使人们能够理解不同个体牙周炎发生、发展的差异,而另一方面,牙周疾病对许多器官系统的潜在影响日益受到关注,牙周医学的兴起开创了崭新的重要研究领域,并有着深远的临床意义。  相似文献   
68.
新生儿期卵巢增大,可形成卵巢囊肿、影响卵巢进入正常位置而形成腹股沟疝,导致小儿性早熟,影响小儿身高及心理发育等。自2006年1月-6月我们连续发现5例新生儿卵巢增大,予以报道。1材料与方法临床资料见表1,应用彩色多普勒超声诊断仪:Philps HD、HDI 5000,高频探头7-10mmHz。行常规下腹部及腹股沟、会阴区扫查。2结果超声检查所见及诊断结果见表1。表1 5例临床资料与超声检查结果比较异及丘脑-垂体-卵巢器质性病变产生过多激素,刺激胎儿卵巢内卵泡增生过大、内液潴溜,是导致卵巢增大的原因[3]。5例新生儿8枚卵巢增大的原因分析,说明胎儿期…  相似文献   
69.
目的 探讨重症急性胰腺炎(SAP)早期治疗体会及外科手术治疗时机和手术方式的选择。方法 对比分析1989—1995年以早期手术为主的36例SAP(A组)与1996—2003年7年中非手术治疗为主的44例SAP(B组)的治愈率和死亡率。结果 B组的死亡率明显低于A组,A组的治愈率低于B组。结论 SAP早期的急性炎症反应期,手术只能加重对机体的打击,加重SAP全身炎症反应,增加手术死亡率。故SAP早期治疗应以非手术疗法为主。当内科治疗无效,手术治疗是唯一的选择,而手术时机的掌握和手术方式的选择更为重要,直接影响手术结果。  相似文献   
70.
对2例经皮球囊椎体成形治疗胸腰椎压缩性骨折患者进行护理,术前做好心理护理,疼痛的护理,功能锻炼的指导,完善相关检查;术后做好生命体征的观察,积极预防骨水泥外渗、肺栓塞等并发症的发生,并指导合理饮食,加强功能锻炼。结果2例术后未发生并发症,痊愈出院,治疗效果满意。  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