全文获取类型
收费全文 | 931977篇 |
免费 | 66355篇 |
国内免费 | 1343篇 |
专业分类
耳鼻咽喉 | 12958篇 |
儿科学 | 24363篇 |
妇产科学 | 23298篇 |
基础医学 | 132923篇 |
口腔科学 | 28247篇 |
临床医学 | 80540篇 |
内科学 | 183284篇 |
皮肤病学 | 19227篇 |
神经病学 | 72170篇 |
特种医学 | 36839篇 |
外国民族医学 | 79篇 |
外科学 | 152075篇 |
综合类 | 18045篇 |
现状与发展 | 1篇 |
一般理论 | 234篇 |
预防医学 | 61738篇 |
眼科学 | 21307篇 |
药学 | 72525篇 |
3篇 | |
中国医学 | 2162篇 |
肿瘤学 | 57657篇 |
出版年
2018年 | 8964篇 |
2017年 | 7032篇 |
2016年 | 7768篇 |
2015年 | 8867篇 |
2014年 | 11985篇 |
2013年 | 17500篇 |
2012年 | 24096篇 |
2011年 | 25042篇 |
2010年 | 14814篇 |
2009年 | 14270篇 |
2008年 | 24607篇 |
2007年 | 25688篇 |
2006年 | 26480篇 |
2005年 | 25435篇 |
2004年 | 24563篇 |
2003年 | 23611篇 |
2002年 | 23157篇 |
2001年 | 54727篇 |
2000年 | 56543篇 |
1999年 | 46954篇 |
1998年 | 10732篇 |
1997年 | 9464篇 |
1996年 | 9594篇 |
1995年 | 8936篇 |
1994年 | 8282篇 |
1993年 | 7600篇 |
1992年 | 35488篇 |
1991年 | 33911篇 |
1990年 | 32735篇 |
1989年 | 31875篇 |
1988年 | 29002篇 |
1987年 | 28251篇 |
1986年 | 26288篇 |
1985年 | 25144篇 |
1984年 | 17833篇 |
1983年 | 15142篇 |
1982年 | 7795篇 |
1981年 | 6772篇 |
1979年 | 15781篇 |
1978年 | 10598篇 |
1977年 | 9052篇 |
1976年 | 7871篇 |
1975年 | 8629篇 |
1974年 | 10466篇 |
1973年 | 9858篇 |
1972年 | 9357篇 |
1971年 | 8852篇 |
1970年 | 8426篇 |
1969年 | 7923篇 |
1968年 | 7200篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
The authors analyze the efficacy of He-Ne laser therapy of amblyopia of various origins in 48 children (81 eyes). Group 1 children were not treated at all in order to assess the visual function background fluctuations (absolute controls). Along with He-Ne laser, used in Group 2, a 'placebo', slit lamp with blinking light, was used in Group 3. Vision acuity was assessed with the use of Sivtsev-Golovin's and Orlova's tables and by visocontrastometry in a blind test. Common visometry has shown a reliable and approximately similar improvement of the vision acuity in Groups 2 and 3 patients, whereas visocontrastometry has not detected any changes of visual function in all the 3 groups. These results cast doubt on the true efficacy of He-Ne laser stimulation of visual function, at least in children, and once again demonstrate that such investigations may be carried out only with a reliable ('blind') control and placebo. 相似文献
992.
M Usui T Kimura J Yamazaki 《The Journal of bone and joint surgery. American volume》1990,72(9):1370-1373
We successfully replanted five amputated legs in five patients and followed the patients for two years or more (average, six years and three months). Although some patients found it impossible to squat and to run because of joint contractures, muscle weakness, or deformities of the foot, all patients could perform other activities without difficulty. None had important pain or any intolerance to cold, and all were satisfied with the results of the replantation. 相似文献
993.
Aberrometry in the diagnosis of eye diseases 总被引:1,自引:0,他引:1
Four methods (by means of Smirnova-Korniushina's aberrometer; with the help of aberroscope--Cherning's lattice; by presenting a figure of a cross; and by automatic refractometry through different portions of the pupil) were used for studying aberration of the optic system of the eye in 490 persons. Among them, 37 were healthy persons, 27--patients with ametropia of moderate degree, 24--with high myopia, 9--with astigmatism above 3.0 D, 16--with monocular diplopia, 327--with keratoconus, 7--with scars of the cornea, 21--with initial cataract, 47--after keratotomy. In norm and in ametropia to 6.0 D, a histogram of refraction distribution by the pupil has a small disperse and a pronounced peak, the Cherning's lattice is straight. In high myopia, the disperse of refraction increases, the peak is slightly pronounced, the lattice is curved along the margins. In astigmatism, the disperse of refraction is great, but there can be peaks. The whole lattice is curved. In monocular diplopia, two more peaks can be seen on the histogram. The lattice is greatly curved. In keratoconus, aberrometry without correction is possible only at the initial stage and shows a rather mixed picture. The histogram of refraction represents a low irregular row. In aberroscopy, the bands are greatly curved, frequently overstep the bounds of the frame that itself looses a form of a circle, becomes oval or polygonal. Contact correction improves the aberration picture considerably. In scars of the cornea, the lattice is distorted and infrequently repeats their forms. In initial cataract, the course of the bands becomes interrupted and rounded spots appear between them.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
994.
Comparison of three immunoassays for diagnosing sensitization to latex in children with spina bifida
B. Niggemann T. Michael A. von Moers U. Seidel R. Wahl L Jacobsen D. Scheffer U. Wahn 《Pediatric allergy and immunology》1996,7(4):164-166
As natural rubber latex (latex) has become more widespread in our environment, physicians have become increasingly aware of the problem of possible allergic reactions. Many fatal and near-fatal incidents have been reported (mainly during surgery) (1—3) and data has been published on groups frequently exposed to latex, such as patients with spina bifida (4—9), healthcare professionals (10—12) and occupationally exposed persons (13). The incidence of latex allergy in children seems to be increasing (14). Tests are therefore needed which can reliably detect sensitization to latex. Our aim was to compare the diagnostic accuracy of three commercial immunoassays for measuring specific IgE in serum to latex. 相似文献
995.
The treatment of neoplasia with interleukin-2 (IL-2) can be complicated by neurological deficits resembling transient Ischemic attack and stroke. We investigated whether interleukin-2 contributes to the natural course of cerebrovascular ischemia and particularly to the pathogenesis of infection-associated stroke. Plasma levels of interleukin-2 were below the level of detectability in almost all measurements. Patients with and without previous infection (n = 11, 805 ±445 U/ml vs n = 19, 824 ± 501 U/ml) did not have significantly higher levels of soluble interleukin-2 receptors than control subjects with (n = 14, 667 ± 229 U/ml) or without vascular risk factors (n = 17, 567 ± 176 U/ml). Receptor levels increased in patients during the first week after stroke (n = 15, 1157 ± 1013, p < 0.02). Levels of soluble T8 antigen (sT8) were higher in patients (n – 26, 320 ± 112 U/ml) than in healthy control subjects (n = 15, 246 ± 92 U/ml; p < 0.05) and sT8 levels increased during the first week after stroke (p < 0.05). These results reflect an immunological response to the cerebral infarct; they do not indicate a general role of the IL-2 system in the pathogenesis of ischemic stroke with or without previous infection. 相似文献
996.
Ezra Susser M.D. Dr.P.H. Molly T. Finnerty M.D. Nancy Sohler M.P.H. 《The Psychiatric quarterly》1996,67(3):165-176
This paper concerns the diagnostic classification of nonaffective acute remitting psychosis (NARP), which we also term acute brief psychosis. We argue that NARP can be delineated from both schizophrenia and the affective psychoses and considered as a single diagnosis. As indicated by the term NARP, four criteria would be central to the diagnosis: 1. nonaffective, 2. acute onset (over less than two weeks), 3. recovery within a brief duration (less than six months), and 4. psychosis broadly defined. We review the rationale and the empirical evidence for this proposed classification. 相似文献
997.
Computer simulations of bone remodeling in response to mechanical stresses can be used to understand normal growth and development of the skeleton or to predict the remodeling of bone in response to prosthetic devices. Using a previously derived bone maintenance theory, a technique for computing bone density distributions was applied to the proximal femur and tibia using two-dimensional, multiple-loading finite element models. The models initially represented solid, homogeneous structures. Using an iterative bone remodeling technique that relates bone apparent density to loading history, the internal distributions of apparent density and elastic modulus for the normal bones were predicted. The finite element models were then modified to represent bones in which porous-coated femoral surface replacements and tibial tray components had been implanted. The same iterative remodeling method was then applied to predict the distribution of bone around these components. The predicted bone density distributions for the natural femur and tibia agree with previously documented normal bone morphology. The predicted bone density distributions around various implanted prostheses were characteristic of the component under investigation and were consistent with clinical and experimental findings of other investigators. In the femoral head, stress shielding occurred underneath the metal surface replacement cup, resulting in lower densities in the femoral head. The addition of a central femoral cup fixation peg caused bone hypertrophy around the peg. In the tibia, the stress concentrations around the pegs also resulted in denser bone, with a concomitant decrease in bone density at more peripheral locations underneath the prosthetic tray. This remodeling technique has the potential to be an important tool in predicting the possible remodeling consequences of new implant design features. 相似文献
998.
Evidence for the presence of substance P-like immunoreactivity in the human cerebellum 总被引:1,自引:0,他引:1
M. Del Fiacco M. T. Perra M. Quartu M. D. Rosa G. Zucca M. C. Levanti 《Brain research》1988,446(1):173-177
Preliminary results on the localization of substance P-like immunoreactivity in the human cerebellum are presented. Cerebella from newborn and adult subjects were examined. While only sporadic positive fibres were detected in the adult tissue, the immunoreactive material appeared more abundant in the cerebella from newborn subjects. Varicose and non-varicose fibres and dot-like nerve terminals were present with different density in various regions. The paucity of immunoreactive perikarya suggests that most of the cerebellar substance P-like immunoreactive material has an extrinsic origin. 相似文献
999.
1000.
200 cervical lateral punctions (CLP) were performed in comatose patients without psychomotor trouble proving this new system to be an alternative for suboccipital punction. This procedure was successful in 90% of the cases. Low importance venous accidents happened but they did not bring any injury or serious consequences to the patients or to cerebrospinal fluid examination results. Vertebral artery injury was not observed. Punctions in corpses showed us that this artery is one cm far from the needle trajectory during the realization of the CLP. 相似文献