全文获取类型
收费全文 | 32327篇 |
免费 | 1611篇 |
国内免费 | 146篇 |
专业分类
耳鼻咽喉 | 414篇 |
儿科学 | 569篇 |
妇产科学 | 568篇 |
基础医学 | 4345篇 |
口腔科学 | 1168篇 |
临床医学 | 2543篇 |
内科学 | 7601篇 |
皮肤病学 | 794篇 |
神经病学 | 2400篇 |
特种医学 | 1277篇 |
外科学 | 5256篇 |
综合类 | 218篇 |
一般理论 | 2篇 |
预防医学 | 1029篇 |
眼科学 | 494篇 |
药学 | 2200篇 |
中国医学 | 46篇 |
肿瘤学 | 3160篇 |
出版年
2022年 | 268篇 |
2021年 | 599篇 |
2020年 | 281篇 |
2019年 | 423篇 |
2018年 | 595篇 |
2017年 | 430篇 |
2016年 | 473篇 |
2015年 | 552篇 |
2014年 | 741篇 |
2013年 | 812篇 |
2012年 | 1285篇 |
2011年 | 1389篇 |
2010年 | 768篇 |
2009年 | 714篇 |
2008年 | 1263篇 |
2007年 | 1334篇 |
2006年 | 1359篇 |
2005年 | 1418篇 |
2004年 | 1373篇 |
2003年 | 1325篇 |
2002年 | 1320篇 |
2001年 | 1220篇 |
2000年 | 1387篇 |
1999年 | 1199篇 |
1998年 | 395篇 |
1997年 | 281篇 |
1996年 | 297篇 |
1995年 | 275篇 |
1994年 | 239篇 |
1993年 | 225篇 |
1992年 | 797篇 |
1991年 | 754篇 |
1990年 | 677篇 |
1989年 | 695篇 |
1988年 | 676篇 |
1987年 | 664篇 |
1986年 | 673篇 |
1985年 | 596篇 |
1984年 | 428篇 |
1983年 | 349篇 |
1979年 | 339篇 |
1978年 | 233篇 |
1977年 | 200篇 |
1975年 | 198篇 |
1974年 | 227篇 |
1973年 | 207篇 |
1972年 | 198篇 |
1971年 | 211篇 |
1970年 | 203篇 |
1969年 | 224篇 |
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
131.
Itsuro Tomita Katsuya Sato Susumu Shirabe Kunihiko Nagasato Akira Satoh Mitsuhiro Tsujihata 《Clinical neurology》2004,44(3):182-186
Serial DWIs were performed in a patient with CJD who developed symptoms acutely and progressed rapidly. DWI discloed an increased signal in the frontal and parietal inner cortical areas, and in the caudate nuclei and putamina 20 days after the onset of symptoms. T2-weighted images showed only signal abnormality in the caudate nuclei and putamina, but not in the cerebral cortex. In the CSF obtained 15 days after the onset of symptoms, total tau protein was markedly elevated and 14-3-3 protein was positive. Measurement of these proteins are highly specific and sensitive for the diagnosis of CJD, but not available as a rapid routine examination at present. DWI is not specific, but useful for making the diagnosis of CJD in the early stage of the disease. 相似文献
132.
K Okajima Y Nagata M Mitsumori T Ishigaki I Kimura Y Nakano K Minato M Komori K Sato T Takahashi 《Radiology》1992,183(2):569-572
To investigate spatial resolution requirements for digitized portal images in radiation therapy, observer performance tests were performed. One hundred twenty portal images were digitized with sampling frequencies of 0.700, 0.350, and 0.175 mm for observation. Receiver operating characteristic analysis was used to determine the acceptable sampling frequency for clinical portal images. The detectability of setup errors was significantly better on the original images than on the digitized images with sampling frequencies of 0.700 mm (P = .005) and 0.350 (P = .046). Some clinical disadvantages might accrue with the use of a sampling frequency of 0.350 mm or larger. 相似文献
133.
Yasuhiro Kinoshita M.D. Ph.D. Isao Sato M.E. Teruhiko Marushima B.E. Taichi Nishimura B.E. 《The International journal of angiology》1994,3(1):36-40
In order to find the three-dimensional distribution of ventricular depolarization potentials in left anterior hemiblock (LAHB) diagnosed by the conventional scalar ECG, 7 subjects with LAHB aged 9 to 62 years old who were otherwise healthy were studied by computer graphic electrocardiography (CGECG).Two modes of the initial ventricular depolarization (IVD) were noted. (1) The IVD appeared irregularly and separately on the mid- to lower central region of the anterior body surface. (2) The IVD appeared in a form rather like a parallelogram on the central region of the anterior body surface. Both (1) and (2) potentials propagated toward the left middle, lower, and lateral regions of the anterior body surface as normally observed; however, they were far lower in voltage than those observed in intact subjects.From the results, it has been concluded that LAHB may be, not a block, but rather a defective ventricular septal conduction.Presented at the 34th Annual Congress, International College of Angiology, Budapest, Hungary, July 1992. 相似文献
134.
Release fluoroimmunoassay (RFIA), a new method of enzyme immunoassay (ELISA), was employed for the detection of specific IgE antibody in patients allergic to Japanese cedar pollen. RFIA clearly discriminated between allergic patients and healthy subjects. Further, RFIA was able to detect the minute IgE antibody at the dilution range of 1/32 of patient's serum. Correlation between the relative fluorescent unit values and the RAST values of sera from 17 patients and seven healthy subjects was very high. The correlation coefficient was 0.87. These findings show that the RFIA has an advantage over the other procedures for the diagnosis of immediate-type hypersensitivity as well as the diagnosis of Japanese cedar pollen. 相似文献
135.
Masaki Q. Fujita Toshiyuki Yasui Bunzo Sato Naomi Uchida Kiyohisa Uchida Osamu Shiratori Kenichi Takeda Keishi Matsumoto 《Cancer science》1992,83(9):995-1001
Shionogi carcinoma 115 (SC115), an androgen-dependent mouse mammary tumor, rapidly loses its androgen responsiveness after androgen withdrawal. The growth of this tumor can also be stimulated by high doses of estrogen or glucocorticoid. In the present study, the maintenance of hormone-responsive growth of SC115 tumors with a high dose of estrogen was examined in castrated male mice using an SCI 15 subline obtained by serial transplantations of SCI 15 tumors in estrogen-treated castrated mice for 3 years (30 generations) (subline E2 ). Seed tumors from both SC115 and subline E2 could rapidly grow in castrated mice given daily injections of testosterone propionate (TP), 17β-estradiol (E2 ), or dexamethasone (Dex) (100 μg/mouse/day) but not in those given vehicle alone. Although SCI 15 and subline-E2 tumors grown with TP or Dex showed temporary regression after steroid withdrawal, the tumors grown with E2 did not show such temporary regression. The TP-, E2 -, or Dex-induced growth of subline-E2 tumors was almost the same as that of the original SCI 15 tumors. However, responsiveness to androgen, estrogen or glucocorticoid of both tumors disappeared within one passage in steroid-depleted castrated mice. The present findings demonstrate that the loss of responsiveness to androgen as well as to high doses of estrogen or glucocorticoid of SCI 15 tumors can be prevented in castrated mice not only with androgen but also with high doses of estrogen. 相似文献
136.
137.
Antiinflammatory properties of the new antirheumatic agent 4-acetylaminophenylacetic acid 总被引:5,自引:0,他引:5
H Fujisawa T Nishimura Y Inoue S Ogaya Y Shibata Y Nakagawa S Sato K Kimura 《Arzneimittel-Forschung》1990,40(6):693-697
The antiinflammatory activity of 4-acetylaminophenylacetic acid (MS-932) was investigated. MS-932 did not suppress the acute inflammation of carrageenin-induced paw edema in rats or of primary swelling in adjuvant arthritic rats. However, prophylactic treatment with MS-932 inhibited secondary inflammation in adjuvant arthritic rats. MS-932 also restored to normal the weight of the spleen and the serum albumin/globulin ratio of adjuvant arthritic rats. In addition to its prophylactic effect, MS-932 had a therapeutic effect on adjuvant arthritis. In in vitro tests, MS-932 did not inhibit prostaglandin E2 biosynthesis from arachidonic acid by sheep seminal vesicle microsomal enzyme or superoxide generation by guinea pig neutrophils stimulated with opsonized zymosan. MS-932 had no analgesic effect in mice and no antipyretic effect in rats. These results indicate that MS-932 suppresses adjuvant arthritis through modulation of the immune system. 相似文献
138.
S Tamura K Ebine K Sato M Lee K Matii M Aihara 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1990,38(2):336-340
A case of atrial septal aneurysm associated with combined valvular disease and coronary-pulmonary fistula (C-PA fistula) was presented. The patient successfully underwent mitral valve replacement, excision and closure of the aneurysm, tricuspid annuloplasty and closure of C-PA fistula. Atrial septal aneurysm is a rare anomaly and its natural course is thought to be generally good without significant clinical symptoms. However, complications such as cerebral and pulmonary embolism, or occlusion of the atrioventricular vales by the prolapsed aneurysm were reported to occur in small number of cases. In this case, diagnosis of the aneurysm was made by 2-D and Doppler echocardiography and further confirmed by cineangiography. Routine echocardiographic examinations will serve as useful noninvasive method for detection and follow up study of this anomaly. 相似文献
139.
K Iwahashi T Ota H Sato H Kanda T Sugimoto M Okada K Nakamura 《Journal of cardiology》1992,22(4):651-659
To determine the relative superiority of a prosthesis in the mitral position, in vivo hemodynamics were examined by Doppler echocardiography, and the results were compared with other types of mechanical mitral valves including 63 Bj?rk-Shiley convexo-concave (BS) values, 30 Duromedics (DM) valves, and 58 Medtronic Hall (MH) valves. For this comparison, the following indices were evaluated: peak velocity of mitral flow (PV), mitral valve orifice area (MVA), mitral valvular regurgitation, New York Heart Association (NYHA) classification, pulmonary capillary wedge pressure (PC), cardiac index (CI) and valve-related complications. On Doppler echocardiograms, PV ranged from 1.2 to 2.0 m/sec with a mean of 1.6 m/sec. There was no evident relationship between the PV and the valve size in each type of prosthesis, and no significant difference in the PVs among the valves. The mean MVA was 2.6 cm2 (25 mm DM, 25 mm MH), which was regarded satisfactory from a clinical standpoint. MVA increased with the increase in the valve size in all types of valves, and of all sizes, MVA was larger in the DM and MH groups than in the BS group. Similarly, the incidence of valvular regurgitation was relatively low in all groups, and the degree of regurgitation proved to be grade II or less in all cases. As for the clinical results, clinical symptoms (NYHA) and hemodynamic states (PC, CI) improved postoperatively, with the differences among the types of prosthetic valves being insignificant. The incidences of thromboembolism, valvular thrombosis, valve failure and prosthetic endocarditis were relatively low in all groups.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
140.
Yoshiyuki Kaneko Tomohiro Nakayama Kosuke Saito Akihiko Morita Ichiro Sato Aya Maruyama Masayoshi Soma Teruyuki Takahashi Naoyuki Sato 《Hypertension research》2006,29(9):665-671
The risk of cerebral infarction (CI) in an individual is dependent on the interplay between genetic risk factors and environmental influences. Binding of thromboxane A2 (TXA2) to its receptor (TP) modulates thrombosis/hemostasis and plays a significant role in the pathogenesis of CI. The aim of the present study was to investigate the relationship between human TP gene single nucleotide polymorphisms (SNPs) and haplotypes and CI in a Japanese population. A genetic association study was performed in 194 CI patients and 365 non-CI subjects by specifically characterizing 6 SNPs in the human TP gene (rs2271875, rs768963, rs2238634, rs11085026, rs4523 and rs4806942). Analysis demonstrated that there were significant differences in the overall distribution of genotypes and dominant or recessive models of rs2271875 and rs768963 between the CI and the non-CI groups. Multiple logistic regression analysis revealed that the C allele of rs768963 was significantly associated with CI (p = 0.029), even after adjusting for confounding factors (odds ratio: 2.41). Further, the C-T-C haplotype of rs768963-rs2238634-rs4806942 was significantly more frequent in the CI group (23.0%) than in the non-CI group (17.7%). These results suggest that specific SNPs and haplotypes may have utility as genetic markers for the risk of CI and that TP or a neighboring gene is associated with the increased susceptibility to CI. 相似文献