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   984827篇
  免费   72117篇
  国内免费   3027篇
耳鼻咽喉   13487篇
儿科学   25457篇
妇产科学   24350篇
基础医学   138767篇
口腔科学   29358篇
临床医学   86708篇
内科学   193825篇
皮肤病学   20288篇
神经病学   75352篇
特种医学   37996篇
外国民族医学   85篇
外科学   158112篇
综合类   24197篇
现状与发展   3篇
一般理论   243篇
预防医学   66475篇
眼科学   22570篇
药学   77471篇
  56篇
中国医学   4453篇
肿瘤学   60718篇
  2021年   8254篇
  2019年   7710篇
  2018年   10915篇
  2017年   8762篇
  2016年   9233篇
  2015年   11031篇
  2014年   14847篇
  2013年   20825篇
  2012年   29003篇
  2011年   30019篇
  2010年   18189篇
  2009年   17189篇
  2008年   28150篇
  2007年   29164篇
  2006年   29486篇
  2005年   28164篇
  2004年   26680篇
  2003年   25607篇
  2002年   24781篇
  2001年   55170篇
  2000年   56904篇
  1999年   47258篇
  1998年   11006篇
  1997年   9718篇
  1996年   9816篇
  1995年   9107篇
  1994年   8425篇
  1993年   7709篇
  1992年   35593篇
  1991年   33983篇
  1990年   32813篇
  1989年   31937篇
  1988年   29048篇
  1987年   28297篇
  1986年   26343篇
  1985年   25191篇
  1984年   17876篇
  1983年   15181篇
  1982年   7849篇
  1979年   15819篇
  1978年   10619篇
  1977年   9084篇
  1976年   7900篇
  1975年   8647篇
  1974年   10479篇
  1973年   9873篇
  1972年   9366篇
  1971年   8861篇
  1970年   8434篇
  1969年   7933篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
961.
Recently, we examined 2 cases of hypertrophic cardiomyopathy (HCM) presenting with sustained ventricular tachycardia (VT). One case was a 62 year old male with midventricular hypertrophy and monomorphic sustained VT. After admission, the efficacies of procainamide, disopyramide, aprindin, flecainide, mexiletine and verapamil were evaluated by means of continuous electrocardiographic monitoring. Verapamil prevented the recurrence of sustained VT and markedly reduced the frequency and number of runs of nonsustained VT. In the electrophysiologic study, rapid VT was induced by double extrastimuli at the right ventricular apex. Intravenous verapamil at a dose of 10 mg prevented the induction of VT. The patient was discharged on verapamil and remains asymptomatic after 3 months of follow up. The other case was a 34 year old female who was a survivor of cardiac arrest. Monomorphic VT was observed on emergency admission and was converted to sinus rhythm by direct current cardioversion after resuscitation. In the electrophysiologic study, rapid VT was induced by double extrastimuli at the right ventricular outflow tract. Verapamil at a dose of 10 mg prevented the induction of VT. These 2 cases of HCM are rare in that they presented with sustained VT. It is also of interest that verapamil, which has been used conventionally in HCM, prevented VT.  相似文献   
962.
In the search for HLA-linked immune response genes that control susceptibility to tuberculosis, we performed HLA typing and measured antibody titers to well-defined Mycobacterium tuberculosis antigenic determinants in 101 patients with sputum smear-positive pulmonary tuberculosis and 64 healthy controls from Surabaya, Indonesia. HLA-DR2 and DQw1 were associated with sputum smear-positive pulmonary tuberculosis (attributable risk = 36% and 39%, respectively), while DQw3 was associated even more strongly with the control group (preventive fraction = 57%). Antibody titers to the TB71 and TB72 epitopes of the 38-kDa protein, present only on tubercle bacilli, were strongly associated with DR2 (Pcorr = .001 and .024, respectively). The association of both the disease and the antibody response to the 38-kDa antigen of M. tuberculosis with Class II HLA genes HLA-DR2 indicates that Ir-gene-mediated regulation of the immune response to this antigen may be of pathogenic significance for the development of sputum smear-positive tuberculosis.  相似文献   
963.
A genomic library of Mycobacterium tuberculosis strain Aoyama B in Escherichia coli K-12 was constructed by cloning Sau 3A I cleaved M. tuberculosis Aoyama B chromosomal DNA into pUC18, pUC181 or pUC182. Clones reacting with anti-PPDs-rabbit-serum were screened by immunoblotting among 3 x 10(4) clones. Seven clones were selected; designating pAT 01, pAT 101, pAT 102, pAT 103, pAT 104, pAT 105 and pAT 201. On Western blotting, they were shown to produce 15 kD (pAT 01, pAT 101, pAT 105), 18 kD (pAT 103) and 60 kD (pAT 102, pAT 201) peptide antigens. Restriction endonuclease map of each of the above clones was composed, and putative coding frames of anti-PPDs-rabbit-serum reactive peptides were deduced by analysing deletion derivatives. Nucleotide sequence of pAT 01, encoding for 15 kD peptide antigen was analyzed, and a Hinf I-Hinf I fragment in pAT 01 was subcloned into pUC 18 lambda CPL 1 to determine the direction of its reading frame. The origin of promoter that drives cloned mycobacterial genes in E. coli was discussed.  相似文献   
964.
965.
966.
Lesions typical of subacute cutaneous lupus erythematosus developed in an elderly woman after 6 months of PUVA (8-methoxypsoralen and longwave ultraviolet light) therapy for psoriasis. Pancytopenia, antibodies to double-stranded DNA, and hypocomplementemia developed concurrently with the appearance of the cutaneous lesions. With discontinuation of photochemotherapy, the cutaneous lesions disappeared and the pancytopenia improved.  相似文献   
967.
Retrosternal dislocations of the clavicle have been reported previously in adults throughout the orthopedic literature. However, in children few cases have been noted in either the pediatric, emergency, or orthopedic literature. The potential for great vessel injury as well as acute airway compromise makes the retrosternal disruption of the sternoclavicular joint a surgical emergency that must be diagnosed quickly. Diagnosis is enhanced by the cephalic tilt view and by computed tomography (CT scan), as planar x-ray and tomography do not always reveal this potentially life-threatening condition. Surgical consultation must be sought acutely; however, management may need to begin prior to definitive repair. Emergency management begins by suspecting the injury, and with immediate airway and circulatory support for the patient.  相似文献   
968.
969.
Infrared imaging (thermography) has developed rapidly over the past 10-15 years as a diagnostic imaging procedure. Despite scientific validation and proven use in the clinical setting, neuromuscular thermography has met with much criticism and skepticism. The emotional and political controversy surrounding thermography has distracted the medical community to such an extent that the real issue of utmost importance to the practicing physician is often ignored. The basic scientific foundation of medicine should preclude the prejudicial influence of emotion, politics, and anecdotes. Scientific investigations, for more than 2 decades now, have demonstrated that neuromuscular thermography is of proven value in the clinical evaluation of various pain disorders and neuromuscular conditions, including radicular pathology.  相似文献   
970.
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