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   50431篇
  免费   3169篇
  国内免费   166篇
耳鼻咽喉   666篇
儿科学   1214篇
妇产科学   1036篇
基础医学   6902篇
口腔科学   3087篇
临床医学   3661篇
内科学   11572篇
皮肤病学   1190篇
神经病学   4019篇
特种医学   1175篇
外国民族医学   1篇
外科学   6307篇
综合类   296篇
一般理论   16篇
预防医学   4712篇
眼科学   1112篇
药学   3544篇
中国医学   351篇
肿瘤学   2905篇
  2023年   380篇
  2022年   745篇
  2021年   1772篇
  2020年   1079篇
  2019年   1465篇
  2018年   1784篇
  2017年   1233篇
  2016年   1303篇
  2015年   1580篇
  2014年   1963篇
  2013年   2594篇
  2012年   3752篇
  2011年   4112篇
  2010年   2207篇
  2009年   1905篇
  2008年   3161篇
  2007年   3125篇
  2006年   2876篇
  2005年   2581篇
  2004年   2208篇
  2003年   2057篇
  2002年   1821篇
  2001年   911篇
  2000年   820篇
  1999年   738篇
  1998年   360篇
  1997年   288篇
  1996年   260篇
  1995年   214篇
  1994年   214篇
  1993年   179篇
  1992年   395篇
  1991年   354篇
  1990年   306篇
  1989年   281篇
  1988年   254篇
  1987年   194篇
  1986年   225篇
  1985年   190篇
  1984年   174篇
  1983年   139篇
  1982年   118篇
  1981年   114篇
  1980年   95篇
  1979年   163篇
  1978年   105篇
  1977年   99篇
  1976年   101篇
  1975年   85篇
  1973年   83篇
排序方式: 共有10000条查询结果,搜索用时 187 毫秒
11.
Background and aimsThe long-term relations between excessive adiposity in early childhood and unfavourable cardiometabolic profiles in later ages are not yet completely understood. We aimed to assess the associations between birth weight (BW) and BMI from 6 months to 6 years of age, with biomarkers indicative of low-grade inflammation, insulin resistance and lipid profiles in adolescence.Methods and resultsRetrospective school-based study with 415 Portuguese adolescents (220 girls), mean age of 14.08 ± 1.6 years old. Anthropometric data from birth to 6 years old was extracted from individual child health book records. Actual weight and height were measured and BMI calculated. Participants were classified at each time point as normal weight or overweight according to WHO reference values. Biomarkers were obtained from venous blood samples. Linear regressions were used to explore the associations between the biomarkers and early life anthropometric indicators. From 2 years onwards, BMI associated positively with the inflammatory score and HOMA-IR in adolescence. Children who were overweight/obese from 2 to 6 years of age presented significantly higher inflammatory score and HOMA-IR later in adolescence. TC/HDL ratio was also positively associated with BMI from the age of 5 years onwards. The associations between BMI and cardiometabolic outcomes remained positive in adolescence, with overweight adolescents presenting a higher inflammatory score, HOMA-IR and TC/HDL than normal weight adolescents.ConclusionA high BMI from an early age was consistently associated with worse inflammatory and lipid profiles and insulin resistance in adolescence. No associations were found between BW and the same studied outcomes.  相似文献   
12.
The main clinical features of tyrosinemia type 1 usually appear in the first months of life, including fever, diarrhea, vomiting, liver involvement, growth failure, and renal proximal tubulopathy with subsequent hypophosphatemic rickets. An early diagnosis is crucial in order to provide specific management and to prevent complications. Here, we report on two cases referred primarily to pediatric nephrologists for the diagnosis of “neonatal tubulopathy” and management of “X-linked hypophosphatemia (XLH),” respectively. Our aim is to emphasize that (1) even a mixed tubulopathy can reveal tyrosinemia, and (2) tyrosinemia is a classic differential diagnosis of XLH that should not be forgotten, especially in the era of the anti-FGF23 burosumab.  相似文献   
13.
14.
15.
16.
BACKGROUND Accurate detection of gastric infection by Helicobacter pylori(H.pylori) and premalignant lesions are important for effective provision of treatment,preventing the development of gastric neoplasia.Optical enhancement systems with optical magnification improved the identification of mucosal superficial and vascular patterns in patients with dyspepsia.AIM To evaluate an optical enhancement system with high-definition magnification,for diagnosis of normal gastric mucosa,H.pylori-associated gastritis,and gastric atrophy.METHODS A cross-sectional,nonrandomized study from November 2015 to April 2016 performed in a single-tertiary academic center from Ecuador.Seventy-two consecutive patients with functional dyspepsia according to the Rome III criteria,were tested for H.pylori using a stool antigen test and were assigned to an Hp+group or an Hp-control group.Esophagogastroduodenoscopy with highdefinition optical magnification and digital chromoendoscopy was performed,and patients were classified into 4 groups,in accordance to the microvasculararchitecture pattern of the mucosa.Interobserver and intraobserver agreement among operators were calculated.RESULTS Of the 72 participants,35 were Hp+ and 37 were Hp-.Among 10 patients with normal mucosal histology in biopsy samples,90% had a Type I pattern of microvascular architecture by endoscopy.Among participants with type IIa and type IIb patterns,significantly more were Hp+ than Hp-(32 vs 8),and most(31 out of 40) had histological diagnoses of chronic active gastritis.Two of the three participants with a histological diagnosis of atrophy had a type III microvascular pattern.The type I pattern predicted normal mucosa,type IIa–IIb predicted H.pylori infection,and type III predicted atrophy with sensitivities of 90.0%,91.4%,and 66.7%,respectively.The intraobserver and interobserver agreements had kappa values of 0.91 and 0.89,respectively.CONCLUSION High-definition optical magnification with digital chromoendoscopy is useful for diagnosis of normal gastric mucosa and H.pylori-associated gastritis with high accuracy,but further studies are needed to determine whether endoscopic diagnosis of gastric atrophy is feasible.  相似文献   
17.
18.
19.
Fibrous dysplasia is a non‐neoplastic developmental process that affects the craniofacial bones, characterized by painless enlargement as a result of bone substitution by abnormal fibrous tissue. Postzygotic somatic activating mutations in the GNAS1 gene cause fibrous dysplasia and have been extensively investigated, as well as being helpful in the differential diagnosis of the disease. Fibrous dysplasia may involve one (monostotic) or multiple bones (polyostotic), sporadically or in association with McCune‐Albright syndrome, Jeffe‐Lichenstein syndrome, or Mazabreud syndrome. This review summarizes the current knowledge on fibrous dysplasia, emphasizing the value of integrating the understanding of its molecular pathogenesis with the clinical, radiological, and histopathological features. In addition, we address important aspects related to the differential diagnosis and patient management.  相似文献   
20.
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