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   10435篇
  免费   320篇
  国内免费   27篇
耳鼻咽喉   147篇
儿科学   157篇
妇产科学   279篇
基础医学   2070篇
口腔科学   203篇
临床医学   517篇
内科学   952篇
皮肤病学   397篇
神经病学   822篇
特种医学   1539篇
外科学   1415篇
综合类   41篇
预防医学   735篇
眼科学   81篇
药学   1054篇
中国医学   90篇
肿瘤学   283篇
  2023年   35篇
  2022年   20篇
  2021年   44篇
  2020年   41篇
  2019年   58篇
  2018年   186篇
  2017年   124篇
  2016年   172篇
  2015年   113篇
  2014年   207篇
  2013年   355篇
  2012年   679篇
  2011年   1025篇
  2010年   452篇
  2009年   149篇
  2008年   747篇
  2007年   912篇
  2006年   886篇
  2005年   711篇
  2004年   636篇
  2003年   641篇
  2002年   552篇
  2001年   366篇
  2000年   477篇
  1999年   261篇
  1998年   74篇
  1997年   47篇
  1996年   33篇
  1995年   43篇
  1994年   23篇
  1993年   18篇
  1992年   19篇
  1991年   21篇
  1990年   28篇
  1989年   20篇
  1988年   24篇
  1985年   30篇
  1984年   20篇
  1983年   21篇
  1982年   29篇
  1981年   29篇
  1980年   29篇
  1979年   27篇
  1978年   28篇
  1976年   19篇
  1975年   26篇
  1974年   18篇
  1973年   18篇
  1967年   17篇
  1963年   19篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
This study describes and compares two methods of atomic absorption spectrometry (AAS) for the selenium (Se) analysis in food: electrothermal AAS (ET AAS) and hydride generation method of AAS (HG AAS). The accuracy of the two methods was established by analysing two biological reference materials: Wheat Flour 1567a and Bovine Liver 1577b from the National Institute of Standards and Technology, USA. Good agreement with certified values was obtained for both methods. The accuracy of ET AAS method is 109% and 103% for Wheat Flour and Bovine Liver, respectively. The respective accuracies for HG AAS method were 88% and 87%. The detection limit obtained for ET AAS was 1 microgram Se/L and for HG AAS 0.02 microgram Se/L. The repeatability of ET AAS method was 5-11% and that of HG AAS 14-17%. Both methods are similar in accuracy and repeatability, but hydride generation (HG AAS) is more sensitive than graphite furnace technique (ET AAS) for determination of selenium in food.  相似文献   
72.
The authors investigated the influence of physical strain at work on radiological signs of hip osteoarthritis. The study included 295 men and 298 women aged over 45 from an urban area who were classified in four groups according to physical demands of their occupation. The evaluation included clinical and radiological signs of hip osteoarthritis. The association between hip osteoarthritis and occupation was analysed using logistic regression. Though not significantly, radiological signs of hip osteoarthritis were common in subjects who worked in a standing position (odds 1.45 for men, 1.50 for women). Clinical signs of osteoarthritis in women were significantly associated with performance in a standing position (odds 3.00), whereas in men the association was more significant for jobs with high physical strain (odds 2.19). There was a sustained trend toward an increase in health risk with years of work in all job categories. Occupation did not appear to influence the development of radiological hiposteoarthritis, but the authors did establish association between clinical signs of hip osteoarthritis and work.  相似文献   
73.
Financing dental health care in the Federation of Bosnia and Herzegovina (FBH) over the last 10 years was analyzed with respect to time before the war, during the 1992-1995 war, and after the war. In the first period (until 1991) the system was centralized, well structured, financed through the communities of interest, and burdened with a lack of financial discipline and high inflation. By the end of 1991, all citizens in the territory of BH Federation had the right to dental health insurance and participated in the price of dental service with 10-50%. During the 1992-1995 war, insurance and financial institutions ceased their work until the establishment of civilian governing authorities. The system of dental services was legalized within the health system as its integral part, yet, because of insufficient financial support, the rights of the insured were not fulfilled. Following the Dayton Peace Agreement in 1995, two systems (Croat and Muslim) were in function in FBH, each based on different legal grounds, and dental care stagnated considerably. The 1997 FBH Law on Health Care and Health Insurance and the Law on the Privatization of companies introduced a unique health system, widening the sources of financing and categories of health insurance. The process of health care privatization has been legalized, but not yet implemented. Lack of definitions of ownership diminish foreign investments, and without foreign financial support the improvements will be slower than needs. The process of health care restructuring will thus directly depend on the solving the political crisis in the country.  相似文献   
74.
75.
Syndromes of intracranial hemorrhage, and particularly subarachnoidal, i.e., intracerebral hemorrhage (SAH and IH) present clinical entities that are the most severe conditions in neurology. Timely recognition, diagnosis and adequate therapy are imperative. The most important factor that aggravates an already difficult prognosis of those entities is cerebral vasospasm. Upon the presented facts, the aim of this investigation was to establish the value and role of administration of selective calcium channel blocker--nimodipine in patients with SAH and IH compared to the degree of neurological and functional impairment, as well as the recovery of the function of consciousness compared to the patients with those syndromes from an earlier period, who were not treated with this medicament. Investigation comprised 30 patients who received nimodipine and 20 patients without this agent in therapeutic program. Results of the investigation confirmed significant difference concerning the neurological recovery, improvement of functional capability and recovery or consciousness disturbances, respectively, in patients who received nimodipine compared to the group without this agent. It can be concluded that nimodipine as calcium channel blocker with multitopic pharmacological effects on mechanism of SAH or IH development, respectively, as well as on the development of complications of those syndromes, particularly to the development of vasospasm and reactive ischemia, with the improvement of hemorrheologic disorders deserves to be included as the unavoidable segment of therapeutic program of SAH and IH syndrome immediately after clinical phenomenology is revealed.  相似文献   
76.
77.
78.
In Belgrade Military Medical Academy 88 males and 1 female (aged 13-55, average 28.6 years) with war craniocerebral injuries (CCI) were secondarily neurosurgically treated from October 1991 trough December 1992. Primary neurosurgical management of these patients was performed in war hospitals in former Yugoslavia. Out of 89 patients, 78 had penetrating, and 11 closed CCI. Out of 55 patients with penetrating CCI who underwent surgery, intracranial debridement was performed in 34 patients. All patients with severe CCI (GCS = 3-8) were severely by disabled or died, and in the majority of patients with minor CCI (GCS = 13-15) the outcome was good (p < 0.01). Statistical analysis showed no significant correlation between the extent of cerebral lesion and the outcome of penetrating CCI (p > 0.05). Eight (10.3%) patients with penetrating CCI died. The outcome of war CCI mostly depended on the severity of injury.  相似文献   
79.
80.
In female patient, aged 41, 3 years ago appeared skin changes of urticarial type, and occasional pain in the joints of shoulders and hands, followed by complete weakness and exhaustion, as well as the occurrence of face and eyelid edema. Laboratory findings confirmed the presence of hypocomplentemia with proteinuria, microhematuria and cylindruria. Histopathologic (HP) finding of skin biopsy was leukocytoclastic vasculitis, and HP finding of the kidneys was mesangioproliferative glomerulonephritis. The regression of skin changes was observed during hospitalization after Dapsone was administered. The therapy started with corticosteroids (Prednisone 40 mg/day with weekly dose from 5 mg to 30 mg). In spite of the therapy, hypocomplementemia and proteinuria up to 335 mg/24 h have maintained for a year in the later controls in an outpatient department. The patient is without discomfort, and renal function is stable.  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