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51.
目的:探讨磷脂酰肌醇3-激酶/蛋白激酶 B(PI3K/AKT)通路在重组人促红细胞生成素( rhEPO)保护新型支气管肺发育不良( BPD)中的作用。方法40只定期受孕的SD大鼠,于孕第15天孕囊内注射脂多糖( LPS)或磷酸盐缓冲液( PBS ),新生大鼠分为4组:对照组、高氧组、rhEPO 组、rhEPO+LY294002组。采用Western blot法和RT-PCR法检测肺组织中BCL-2和Caspase-9蛋白及mRNA表达。结果高氧组、rhEPO+LY294002组新生大鼠肺组织BCL-2蛋白及mRNA表达减少, Caspase-9蛋白及 mRNA 表达明显增加;rhEPO组BCL-2蛋白及mRNA表达增加, Caspase-9蛋白及mRNA表达减少;于高氧暴露第1、7、14天各组间的差异均有统计学意义( P<0.05)。结论宫内炎性暴露联合生后高氧可导致肺细胞凋亡增加,rhEPO可能通过减少肺细胞凋亡,对新型 BPD 起一定的保护作用,其机制可能与 PI3K/AKT信号转导通路有关。  相似文献   
52.
目的 了解鄞州区0~6月龄婴儿发育性髋关节异常(developmental dysplasia of hip,DDH)的流行病学特征,探讨DDH 的临床管理模式。方法 由鄞州区妇幼保健机构社区医师和鄞州区第二医院围生医生共同负责完成DDH 的临床初筛工作,可疑或异常者转儿科进一步检查,并予B 超筛查,对不同人群分别进行早期干预、复查、随访及骨盆正位X 线片检查,必要时转小儿骨科治疗。结果 2012 年5 月至2013 年5 月,共6 890 例0~6月龄婴儿进行髋关节B 超筛查,初筛阳性率5.73%(395/6 890),复查阳性率0.59%(34/5729);月龄越小筛查阳性率越高,差异有统计学意义(P<0.05)。新生儿及1~3月龄婴儿初筛阳性率高,但复查阳性率明显降低,差异有统计学意义(P<0.05);4~6月龄婴儿初筛及复查阳性率差异无统计学意义(P >0.05)。结论 鄞州区采取的社区门诊检查- 区医院儿科复查-B 超筛查及转诊治疗的管理模式,可作为基层推进DDH 的早发现和早治疗的有效手段。  相似文献   
53.
实验性髋臼发育不良的病理形态学研究   总被引:1,自引:0,他引:1  
目的 :探讨造成髋关节发育不良的病理发病机制。方法 :将 18只幼兔的左髋关节屈曲膝关节伸直位石膏固定 4周 ,比较双侧髋关节的X线片及病理组织学变化。结果 :髋关节屈曲膝关节伸直位石膏固定 4周造成了髋关节发育不良的动物模型。髋臼变浅、股骨头变小、向外上方移位。X线片可见髋臼指数增大 ,由固定前的 (2 8.44± 3 .91)°增大为 (3 3 .17± 3 .65 )° ;臼头指数减小 ,由固定前的 (75 .2 0± 4.41) %减小为 (5 8.71± 8.2 1) %。组织学观察可见关节软骨退行性改变。结论 :髋关节屈曲膝关节持续伸直位状态 ,容易造成髋关节发育不良。随着时间的延长 ,病理变化加重。及早复位 ,髋关节可以恢复正常  相似文献   
54.

Background  

Pericapsular acetabuloplasty procedures have been widely used as an integral component of combined surgery to treat developmental hip dislocation after walking age. The stability of the acetabuloplasty and the maintenance of the acetabular correction will depend on the structural integrity of the iliac crest autograft, which, traditionally, has been inserted as the interposition material. Problems related to the use of an autograft have been encountered by various surgeons—including the authors—namely, graft displacement and resorption, which may necessitate internal fixation or result in revision surgery. To overcome autograft failure, the use of an allograft as the interposition material has been introduced by some surgeons. This study describes the radiologic results of 147 hips treated for developmental hip dislocation by means of a standard protocol of open hip reduction and pericapsular acetabuloplasty with a contoured iliac crest allograft as the interposition material.  相似文献   
55.

Background

The management of high-grade esophageal dysplasia has included surveillance, endoscopic ablative techniques, and esophagectomy. Herein we describe an alternative treatment, laparoscopic transgastric esophageal mucosal resection.

Methods

Laparoscopic transgastric esophageal mucosal resection was accomplished through an anterior gastrotomy. The mucosa was stripped from the Z-line to the proximal extent of the abnormal epithelium. The gastrotomy then was closed with a linear stapler, and a Nissen fundoplication was performed.

Results

Six patients with high-grade dysplasia of the distal esophagus underwent mucosal resection. After 4 to 7 years of endoscopic surveillance, all patients have regenerated squamous epithelium. One patient developed nondysplastic Barrett's esophagus after 2 years and was treated medically. Two strictures were treated successfully with dilatation.

Conclusions

Laparoscopic transgastric esophageal mucosal resection was a reasonable treatment for high-grade dysplasia in this small sample of patients. This technique is a potential alternative treatment for high-grade dysplasia of the esophagus.  相似文献   
56.

Purpose  

To assess the influence of treating developmental dysplasia of the hip (DDH) with the abduction brace on locomotor development in children.  相似文献   
57.

Background

Cotyloplasty is a technique that involves making a perforation of the medial wall of a shallow acetabulum and then inserting an acetabular cup with the medial aspect of its dome beyond the Kohler line. The purpose of this study was to evaluate the results of cementless total hip arthroplasty (THA) using cotyloplasty with focusing on the amount of medial cup protrusion.

Methods

Sixteen hips with insufficient acetabulum in sixteen patients were treated by cementless THA using cotyloplasty. The average patient age was 47 years. The diagnoses included dysplastic hip (12) and infection sequelae (4). All the patients were followed up for at least 2 years. Clinically, the Harris hip scores were assessed and radiologically, the amount of cup protrusion, the hip center movement and cup fixation were evaluated.

Results

The average Harris hip score improved from 57 to 94 postoperatively. The average proportion of cup surface beyond the Kohler line was 44.1% and the hip centers were medialized by an average of 23 mm. Stable fixation of the acetabular cup was achieved in all the cases except one. In this one case, migration of the cup was detected 2 weeks postoperatively and a reoperation was performed.

Conclusions

Using cotyloplasty, good coverage of the acetabular cup was obtained without a block bone graft, and the hip joint centers were medialized. However, the safety margin for the amount of protrusion should be established.  相似文献   
58.
目的 通过计算机辅助设计有限元分析,找寻髋臼内壁截骨的合适内移范围,为临床工作提供理论依据.方法 利用SolidWorks 2005软件,建立髋臼发育不良骨盆的三维模型,模拟髋臼内壁内移截骨术式,使髋臼内壁骨从未完全陷入盆腔内保持2 mm骨性接触处开始,逐渐内移至完全陷入盆腔内7 mm处,每隔1 mm为1个实验组,分成10个实验组.每组髋臼人为划成4个象限,分别对各组假体臼-骨界面间进行计算机模拟对比力学实验分析,测量出髋臼假体-骨界面间的Mises应力及剪切应力值,找寻出应力分布较为均匀的实验组.结果 Mises应力及剪切应力均有1个象限内的值较大,通过2次统计学分析计算,得出实验结果.结论 当髋臼内壁内移至未完全陷入盆腔内1 mm处到完全陷入盆腔内1 mm处的范围内,髋臼假体-骨界面间的应力分布均匀,最佳位置在完全陷入盆腔内1 mm处.  相似文献   
59.
Children diagnosed with Pervasive Developmental Disorder Not Otherwise Specified (PDD-NOS) and Asperger Syndrome (AS) may be characterised by a similar perceptual focus on details as children with autistic disorder (AD). This was tested by analysing their performance in a visuoperceptual task [the Children’s Embedded Figure Test (CEFT)] and a graphic reproduction task [the Rey Complex Figure Task (Rey CFT)]. Control groups were children with Tourette Syndrome (TS) and typically developing children. The TS sample performed similarly to the normal control group in both tasks. The CEFT results did not show the expected preference for local processing in children with PDD-NOS. However, the Rey CFT data revealed that the children with this lesser variant of PDD processed visuospatial information in a fragmented way and were deficient in global processing.  相似文献   
60.
The use of combined positive and negative contingencies markedly reduced ruminative behavior in a severely mentally retarded, blind 20-year-old male residing in a residential treatment facility. A 95.4% decrease in rumination events occurred from baseline to follow-up. This procedure is offered as an effective and convenient treatment for chronic rumination.  相似文献   
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