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   41109篇
  免费   3061篇
  国内免费   121篇
耳鼻咽喉   382篇
儿科学   1571篇
妇产科学   1120篇
基础医学   5593篇
口腔科学   539篇
临床医学   5203篇
内科学   7644篇
皮肤病学   720篇
神经病学   4310篇
特种医学   913篇
外科学   4287篇
综合类   603篇
一般理论   40篇
预防医学   4855篇
眼科学   723篇
药学   2605篇
中国医学   57篇
肿瘤学   3126篇
  2023年   277篇
  2022年   521篇
  2021年   1017篇
  2020年   644篇
  2019年   1050篇
  2018年   1135篇
  2017年   812篇
  2016年   917篇
  2015年   977篇
  2014年   1364篇
  2013年   2032篇
  2012年   3006篇
  2011年   3073篇
  2010年   1719篇
  2009年   1430篇
  2008年   2467篇
  2007年   2714篇
  2006年   2618篇
  2005年   2482篇
  2004年   2228篇
  2003年   2045篇
  2002年   1994篇
  2001年   475篇
  2000年   455篇
  1999年   429篇
  1998年   415篇
  1997年   353篇
  1996年   297篇
  1995年   259篇
  1994年   216篇
  1993年   245篇
  1992年   325篇
  1991年   316篇
  1990年   295篇
  1989年   285篇
  1988年   302篇
  1987年   247篇
  1986年   232篇
  1985年   184篇
  1984年   188篇
  1983年   162篇
  1982年   136篇
  1981年   134篇
  1980年   128篇
  1979年   152篇
  1978年   136篇
  1977年   111篇
  1975年   105篇
  1974年   138篇
  1973年   123篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
32.
33.

Background  

Skin and soft tissue infections are increasingly prevalent clinical problems, and it is important for health care practitioners to be well trained in how to treat skin abscesses. A realistic model of abscess incision and drainage will allow trainees to learn and practice this basic physician procedure.  相似文献   
34.
35.
36.
Background. Facial acne scarring has been treated with multiple methods with varying degrees of improvement. Although the 1,320 nm neodymium:yttrium-aluminum-garnet (Nd:YAG) laser has been widely used to improve photoaging, studies analyzing its effects on atrophic acne scarring are limited.
Objective. To evaluate the efficacy of a dynamic cryogen-cooled 1,320 nm Nd:YAG laser for the treatment of atrophic facial acne scars in a larger cohort of patients with long-term follow-up.
Methods. Twenty-nine patients (skin phototypes I–IV) with facial acne scarring received a mean of 5.5 (range 2–17) treatments with a 1,320 nm Nd:YAG laser. Objective physician assessment scores of improvement were determined by side-by-side comparison of preoperative and postoperative photographs at a range of 1 to 27 months (mean 10.4 months) postoperatively. Subjective patient self-assessment scores of improvement were also obtained.
Results. Acne scarring was significantly improved by both physician and patient assessment scores. Mean improvement was 2.8 (  p < .05  ) on a 0- to 4-point scale by physician assessment and 5.4 (  p < .05  ) on a 0- to 10-point scale by patient assessment. No significant complications were observed.
Conclusions. Nonablative laser skin resurfacing with a 1,320 nm Nd:YAG laser can effectively improve the appearance of facial acne scars with minimal adverse sequelae.  相似文献   
37.
38.
Results of a study observing autistic children's interactions with nonhandicapped and autistic peers are reported. Six 8- to 12-year-old autistic children played in dyads with younger, normally developing kindergarten children and with nonhandicapped peers matched on chronological age for 10 15-minute sessions spaced over 3 weeks and then with a playmate of the alternate age for another 10 sessions. After intervention, all subjects showed gains in proximity, orientation, and responsiveness when playing with nonhandicapped peers and with autistic classmates. Same-age nonhandicapped playmates initiated more frequently than did younger nonhandicapped playmates and were better able to modify their initiations in ways that increased the likelihood of response from the autistic children.  相似文献   
39.
This study examined the use and effectiveness of the Alert assessment form. The form is part of the Alert system, used by one large acute care hospital to identify patients with a propensity for violence. All reported incidents of patient violence from August 1, 2003, through December 31, 2004, were included in patient charts. One hundred seventeen violent patient charts were reviewed and compared with 161 non-violent patient charts, randomly chosen from the same time period. Overall use of the Alert assessment form for violent and non-violent patients was 75.7% and 35.4%, respectively. The assessment form was found to have moderate sensitivity (71%) and high specificity (94%). It is reasonably effective in identifying potentially violent or aggressive patients when it is used according to protocol. Efforts to improve the tool are warranted, as is evaluation of its benefit in settings with low prevalence of violence. Also, greater effort must be taken to prevent violence once an aggressive patient has been identified.  相似文献   
40.
Akt, a Serine/Threonine protein kinase, mediates growth factor-associated cell survival. Constitutive activation of Akt (phosphorylated Akt, P-Akt) has been observed in several human cancers, including lung cancer and may be associated with poor prognosis and chemotherapy and radiotherapy resistance. The clinical relevance of P-Akt in non-small cell lung cancer (NSCLC) is not well described. In the present study, we examined 82 surgically resected snap-frozen and paraffin-embedded stage I to IIIA NSCLC samples for P-Akt and Akt by Western blotting and for P-Akt by immunohistochemistry. P-Akt protein levels above the median, measured using reproducible semiquantitative band densitometry, correlated with a favorable outcome (P = 0.007). Multivariate analysis identified P-Akt as a significant independent favorable prognostic factor (P = 0.004). Although associated with a favorable prognosis, high P-Akt levels correlated with high tumor grade (P = 0.02). Adenocarcinomas were associated with low P-Akt levels (P = 0.039). Akt was not associated with either outcome or clinicopathologic variables.Cytoplasmic (CP-Akt) and nuclear (NP-Akt) P-Akt tumor cell staining was detected in 96% and 42% of cases, respectively. Both CP-Akt and NP-Akt correlated with well-differentiated tumors (P = 0.008 and 0.017, respectively). NP-Akt also correlated with nodal metastases (P = 0.022) and squamous histology (P = 0.037).These results suggest P-Akt expression is a favorable prognostic factor in NSCLC. Immunolocalization of P-Akt, however, may be relevant as NP-Akt was associated with nodal metastases, a known poor prognostic feature in this disease. P-Akt may be a potential novel therapeutic target for the management of NSCLC.  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