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   29411篇
  免费   1658篇
  国内免费   112篇
耳鼻咽喉   177篇
儿科学   554篇
妇产科学   450篇
基础医学   3837篇
口腔科学   885篇
临床医学   2129篇
内科学   7107篇
皮肤病学   650篇
神经病学   2685篇
特种医学   1269篇
外科学   4206篇
综合类   122篇
一般理论   1篇
预防医学   996篇
眼科学   551篇
药学   2325篇
中国医学   69篇
肿瘤学   3168篇
  2023年   152篇
  2022年   196篇
  2021年   583篇
  2020年   348篇
  2019年   477篇
  2018年   578篇
  2017年   455篇
  2016年   577篇
  2015年   599篇
  2014年   826篇
  2013年   963篇
  2012年   1468篇
  2011年   1659篇
  2010年   852篇
  2009年   797篇
  2008年   1439篇
  2007年   1488篇
  2006年   1330篇
  2005年   1352篇
  2004年   1325篇
  2003年   1264篇
  2002年   1309篇
  2001年   967篇
  2000年   981篇
  1999年   966篇
  1998年   372篇
  1997年   289篇
  1996年   277篇
  1995年   208篇
  1994年   194篇
  1993年   180篇
  1992年   677篇
  1991年   580篇
  1990年   620篇
  1989年   589篇
  1988年   504篇
  1987年   469篇
  1986年   460篇
  1985年   409篇
  1984年   287篇
  1983年   239篇
  1980年   94篇
  1979年   245篇
  1978年   143篇
  1977年   130篇
  1975年   101篇
  1974年   95篇
  1972年   105篇
  1971年   103篇
  1969年   101篇
排序方式: 共有10000条查询结果,搜索用时 328 毫秒
1.
Finasteride is standard medical treatment for androgenetic alopecia; however, no large studies with 5 years or more of follow up have been performed in Japan. The authors followed Japanese men with androgenetic alopecia treated with finasteride for 5 years to evaluate long‐term treatment efficacy. Of 903 men treated with finasteride (1 mg/day), 801 patients were evaluated over 5 years by modified global photographic assessment. Although the proportion of improvement was high (99.4%), modified global photographic assessment scores after 5 years of treatment were lower in patients with more advanced disease as measured by the modified Norwood–Hamilton scale. After separating patients into “sufficient” and “insufficient” efficacy groups according to the modified global photographic assessment score after 5 years (scores ≥6 and <6, respectively), multivariate analysis showed that independent risk factors of insufficient efficacy were age at start of treatment of 40 years or more (P = 0.021) and classification on the modified Norwood–Hamilton scale (P < 0.001), whereas presence of stress at start of treatment was a negative predictor (P = 0.025). In conclusion, continuous finasteride treatment for 5 years improved androgenetic alopecia with sustained effect among Japanese. Younger age and less advanced disease at start of treatment were the key predictors of higher finasteride efficacy.  相似文献   
2.
3.
Two cultivars of Japanese parsley were harvested in different seasons; their antioxidant capacities were evaluated by oxygen radical absorbance capacity (ORAC) methods, and the contents of hydrophilic and lipophilic antioxidants were compared. Japanese parsley possessed potent antioxidant capacities both in hydrophilic and lipophilic extracts when evaluated by ORAC methods. LC/MS/MS analyses revealed that chlorogenic acid and four kinds of quercetin glycosides were major antioxidants in the hydrophilic extract. Lutein was the main contributor to the antioxidant capacity of the lipophilic extract. Antioxidant capacities of the hydrophilic extracts of both cultivars tended to be higher in winter because of the increase in the contents of chlorogenic acid and quercetin glycosides. An obvious trend in the lipophilic antioxidant capacities or lutein contents was not observed irrespective of the cultivar.  相似文献   
4.
5.
Early onset periodontitis is rarely seen in infants, though often leads to an acute and serious clinical course when encountered in such patients. Autoimmune neutropenia presents systemic and dental symptoms, as depressed resistance to bacterial infection is caused by a disorder that reduces the number of neutrophils. This disease can result in not only gingival inflammation but also destruction of periodontal tissues, such as attachment loss, alveolar bone absorption, and early tooth loss in primary as well as mixed dentition. Here, we report treatment of a child with marginal periodontitis from the age of 3 years–7 years 9 months. No systemic manifestations were noted until 3 years of age, thus the patient had never received a detailed examination or medication related to the disease. Following examinations at our department, we referred the patient to a pediatrician at our university hospital for possible systemic disease, who made a diagnosis of autoimmune neutropenia. Although administration of antibiotics and professional dental care were continued, neutrophil count was not increased and progressive periodontal destruction was observed. Extraction of teeth with poor prognosis was performed and a prosthetic strategy for the missing teeth developed. It is important to recognize that periodontitis along with autoimmune neutropenia can appear in infants, even though the incidence is quite low. Early detection and early treatment of this disease is necessary for delaying progression of periodontitis and optimal occlusal induction of permanent teeth.  相似文献   
6.
Idiopathic myointimal hyperplasia of mesenteric veins (IMHMV) is a rare and poorly understood ischemic colitis that occurs in the rectosigmoid colon of predominantly young, previously healthy, male patients. A 76‐year‐old Japanese man presented to our hospital with a 1‐year history of worsening diarrhea, lower abdominal pain, and weight loss (−6 kg). Laboratory evaluation revealed white blood cell count of 13 200/μL, C‐reactive protein level of 2.0 mg/dL (normal range, 0.0–0.3), and negative results for stool culture (including Clostridium difficile). Colonoscopy showed circumferential and edematous narrowing of the sigmoid colon with deep longitude ulceration. Biopsy was done and examination of the specimen demonstrated no specific ischemia. The patient was treated with bowel rest, antibiotics, and i.v. fluids; however, his symptoms worsened. Finally, sigmoidectomy was carried out. Histological examination demonstrated significant myointimal hyperplasia of mesenteric veins leading to thickening and stenosis of the venous lumen. Therefore, the final diagnosis was IMHMV. Three months following sigmoidectomy, he was asymptomatic.  相似文献   
7.
8.
9.
10.
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