全文获取类型
收费全文 | 39923篇 |
免费 | 1986篇 |
国内免费 | 221篇 |
专业分类
耳鼻咽喉 | 327篇 |
儿科学 | 917篇 |
妇产科学 | 500篇 |
基础医学 | 5219篇 |
口腔科学 | 867篇 |
临床医学 | 2573篇 |
内科学 | 10189篇 |
皮肤病学 | 1384篇 |
神经病学 | 2951篇 |
特种医学 | 1367篇 |
外科学 | 6862篇 |
综合类 | 187篇 |
一般理论 | 1篇 |
预防医学 | 1001篇 |
眼科学 | 934篇 |
药学 | 2513篇 |
中国医学 | 83篇 |
肿瘤学 | 4255篇 |
出版年
2023年 | 207篇 |
2022年 | 446篇 |
2021年 | 758篇 |
2020年 | 424篇 |
2019年 | 559篇 |
2018年 | 783篇 |
2017年 | 627篇 |
2016年 | 763篇 |
2015年 | 761篇 |
2014年 | 1082篇 |
2013年 | 1230篇 |
2012年 | 2032篇 |
2011年 | 2235篇 |
2010年 | 1347篇 |
2009年 | 1163篇 |
2008年 | 2027篇 |
2007年 | 2256篇 |
2006年 | 2279篇 |
2005年 | 2416篇 |
2004年 | 2374篇 |
2003年 | 2398篇 |
2002年 | 2267篇 |
2001年 | 938篇 |
2000年 | 901篇 |
1999年 | 945篇 |
1998年 | 582篇 |
1997年 | 461篇 |
1996年 | 470篇 |
1995年 | 392篇 |
1994年 | 328篇 |
1993年 | 321篇 |
1992年 | 568篇 |
1991年 | 496篇 |
1990年 | 503篇 |
1989年 | 507篇 |
1988年 | 473篇 |
1987年 | 413篇 |
1986年 | 413篇 |
1985年 | 365篇 |
1984年 | 317篇 |
1983年 | 237篇 |
1982年 | 144篇 |
1981年 | 131篇 |
1980年 | 122篇 |
1979年 | 198篇 |
1978年 | 151篇 |
1977年 | 151篇 |
1976年 | 104篇 |
1974年 | 130篇 |
1972年 | 122篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Masanori Hara M.D. Reiko Yoshida M.D. Susumu Inaba M.D. Akira Higuchi M.D. Yoshifumi Suzuki M.D. Toshio Okada M.D. Takakuni Tanizawa M.D. 《Pediatrics international》1991,33(3):335-344
The aim of this study was to assess the significance of C3 deposition in IgA nephropathy in children and adolescents. One hundred and two patients aged 5–21 years (57 male and 45 female) were studied. The findings of C3 deposition were classified into 8 groups by immunofluorescent (IF) pattern and intensity as follows: group MC3+ (N = 12): mesangiocapillary pattern and 3+ in intensity; group MC2+ (N = 13): mesangiocapillary and 2+; group MC1 + (N = 4): mesangiocapillary and 1 +; group M3+ (N = 11): mesangial and 3+; group M2+ (N = 24): mesangial and 2+; group M1 + (N=18): mesangial 1 +; group S (N = 12): only segmentally positive; and group N (N = 8): negative. Histological changes were scored semiquantitatively as an activity index (cellular proliferation, necrosis, interstitial cell infiltration, and cellular crescents) and a chronicity index (mesangial sclerosis, segmental and global glomerular sclerosis, fibrous crescents, adhesion and tubulo-interstitial change). IF findings were scored semiquantitatively and laboratory findings were also studied. The following results were obtained: 1) The scores of total activity index in MC groups were higher than in the M, S or N groups, and the greater the degree of C3 deposition, the higher the score; 2) Such result was not evident in the chronicity index; 3) High IF scores of IgG and IgM were found in the MC3+ and MC2+ groups; 4) Hematuria was more severe in MC3+ and MC2+ than in other groups, and proteinuria was more prominent in the MC than other groups. Thus the degree of C3 deposition was parallel with histological activity and urinary findings. 相似文献
82.
-Hydroperoxy diethyl peroxide, a novel compound found in the tunic of ascidians, has two peroxide moieties per molecule. Since ascidians are a widely served food item in Japan, human exposure to this compound potentially exists in the seafood preparation industries. No toxicological data have so far been published on this compound, and so we determined the intraperitoneal 6-day LD50 in mice and conducted histopathological examinations. The 6-day LD50, was found to be 199 mg/kg with 95% confidence limits of 126–314 mg/kg. Histopathological examination revealed necrosis induced in a variety of cells that had been directly exposed to the compound. These cells included hepatocytes, parenchymal pancreatic cells and fat cells. It is concluded that direct contact with this compound is likely to elicit cellular necrosis of various organs. The specific toxicological effects are probably dependent on the route of exposure. 相似文献
83.
Akira Fukushima 《Psychiatry and clinical neurosciences》1994,48(Z1):1-4
Abstract: Historical changes in forensic psychiatric evaluation on criminal responsibility and proceedings in psychopathological findings of amphetamine psychosis are reviewed at first. The classification of amphetamine related mental disorders are proposed in 6 types. Among them, the clinical characteristics and psychopathological features of “Anxiety-situational reaction type” (Fukushima) are described. According to some reasonable grounds, offenders diagnosed as anxiety-situational reaction type should be evaluated as diminished responsibility in place of irresponsibility. Finally, two cases of murder committed under the influence of amphetamine, are reported in detail. 相似文献
84.
Nobuaki Miyazono M.D. Hiroki Inoue Akira Hori Ichiroh Kanetsuki Jurio Shimada Masayuki Nakajo 《Cardiovascular and interventional radiology》1994,17(1):36-37
We present a 44-year-old woman in whom a bronchialto-coronary artery communication via the conus branch was discovered after distal bronchial artery embolization with gelatin sponge for hemoptysis. If this bronchial-to-coronary artery anastomosis, not visible prior to embolization, had been inadvertently embolized, the patient could have developed a myocardial infarction. To reduce the likelihood of a serious complication, the possibility of this anastomosis should be kept in mind and angiography should be repeated before attempting proximal bronchial artery embolization. 相似文献
85.
Pigeons were trained to perform simultaneous pattern and color discrimination tasks. After their training was completed, bilateral electrolytic lesions were made in the ventral lateral geniculate nucleus (GLv). Following the surgery, they were retrained to their preoperative performance levels. Lesions of GLv caused no deficits in pattern discrimination performance. The birds which had been trained for discrimination of red vs. magenta showed a slight decline in their performance. This impaired performance on color discrimination was not, however, as severe as that of a bird with lesions in the nucleus rotundus. These results suggest that GLv plays some role in the detection of short wavelengths of light. 相似文献
86.
Middle latency auditory evoked potentials (MAEP) were recorded in 30 normal subjects and in 19 age-matched patients with temporal lobe lesions. MAEP appeared to be differentially affected by the specific structures involved within the temporal lobe. In the majority of patients with lesions involving the auditory area and/or auditory radiation, Na-Pa amplitude was significantly reduced over the involved hemisphere. No similar reduction in amplitude was noted in subjects with lesions not involving the auditory structures within the temporal lobe. We also observed a shift in a Pa latency over the involved hemisphere in patients with temporal lobe lesions involving the auditory structures. This latency shift was less pronounced than the amplitude reduction. The generators of MAEP in humans are discussed according to these findings and to the available literature. Normal intersubject variability of the conventional amplitude measures, and the occasional myogenic contamination of the response, limits establishing reliable criteria for abnormality that can be applied clinically for the diagnosis of patients with temporal lobe disorders. 相似文献
87.
88.
F Omata Y Ichikawa Y Kushibiki H Shimizu M Yoshida M Komatsuda S Arimori 《American journal of hematology》1992,40(2):160-161
89.
Masafumi Yamaguchi Shinsuke Mii Takashi Kai Hisanobu Sakata Akira Mori 《Surgery today》1997,27(9):863-867
Two elderly women complaining of intermittent claudication complicated with persistent sciatic artery are herein reported.
A direct femoral arteriogram showed hypoplasty of the superficial femoral artery and an unnatural anatomical relationship
between the distal superficial femoral artery and the proximal popliteal artery, thus suggesting the presence of persistent
sciatic artery. The diagnosis of persistent sciatic artery was finally made based on the aortography findings including the
iliac arterial system and computed tomography (CT) scan. Magnetic resonance imaging (MRI) was helpful to demonstrate the entire
image of this anomaly in cases with non-thrombolized sciatic artery. These diagnostic methods were useful in designing the
optimal surgical strategy. The first case with a gluteal pulsating mass underwent exclusion of the persistent sciatic artery
including the aneurysm through a retroperitoneal approach with a combination of femorotibial bypass, while the second case
with thrombosed persistent sciatic artery only underwent femoropopliteal bypass. To recognize such a rare lesion, awareness
of the differential diagnosis is important, and to provide appropriate treatment, an accurate whole image including adequate
angiography, a CT scan, and magnetic resonance imaging is necessary. 相似文献
90.