全文获取类型
收费全文 | 165888篇 |
免费 | 7600篇 |
国内免费 | 1131篇 |
专业分类
耳鼻咽喉 | 2466篇 |
儿科学 | 2834篇 |
妇产科学 | 2667篇 |
基础医学 | 25511篇 |
口腔科学 | 3696篇 |
临床医学 | 15593篇 |
内科学 | 29932篇 |
皮肤病学 | 4865篇 |
神经病学 | 13886篇 |
特种医学 | 8720篇 |
外科学 | 21184篇 |
综合类 | 1060篇 |
现状与发展 | 4篇 |
一般理论 | 39篇 |
预防医学 | 9618篇 |
眼科学 | 4145篇 |
药学 | 14084篇 |
51篇 | |
中国医学 | 1580篇 |
肿瘤学 | 12684篇 |
出版年
2024年 | 763篇 |
2023年 | 1276篇 |
2022年 | 3154篇 |
2021年 | 5245篇 |
2020年 | 2720篇 |
2019年 | 3800篇 |
2018年 | 4426篇 |
2017年 | 3567篇 |
2016年 | 4628篇 |
2015年 | 6289篇 |
2014年 | 7531篇 |
2013年 | 8899篇 |
2012年 | 13324篇 |
2011年 | 12770篇 |
2010年 | 7333篇 |
2009年 | 6322篇 |
2008年 | 9129篇 |
2007年 | 8875篇 |
2006年 | 8056篇 |
2005年 | 7510篇 |
2004年 | 6653篇 |
2003年 | 5799篇 |
2002年 | 5107篇 |
2001年 | 4035篇 |
2000年 | 3743篇 |
1999年 | 2949篇 |
1998年 | 1238篇 |
1997年 | 985篇 |
1996年 | 785篇 |
1995年 | 733篇 |
1994年 | 623篇 |
1993年 | 590篇 |
1992年 | 1364篇 |
1991年 | 1342篇 |
1990年 | 1202篇 |
1989年 | 1172篇 |
1988年 | 1050篇 |
1987年 | 1061篇 |
1986年 | 848篇 |
1985年 | 885篇 |
1984年 | 668篇 |
1983年 | 532篇 |
1982年 | 377篇 |
1981年 | 386篇 |
1980年 | 329篇 |
1979年 | 536篇 |
1978年 | 424篇 |
1977年 | 306篇 |
1974年 | 342篇 |
1973年 | 347篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
It is often difficult to make a clinical or histologic diagnosis of erythrodermic mycosis fungoides (MF) and Sézary syndrome (SS). Whereas the histologic parameters for making a diagnosis of MF with well-developed patch and plaque stage lesions are clearly defined, the same criteria appear to be less relevant for diagnosing MF in patients with erythroderma secondary to the disease. In order to better define the histologic features of erythrodermic MF and SS, we studied 28 routine histologic sections of 17 patients with known erythrodermic MF or SS. Sections were reviewed independently by 2 dermatopathologists. Each of 24 parameters was scored semi-quantitatively and the data were compared to data previously reported from a group of 64 patients with limited patch and plaque stage lesions of MF. When compared to biopsies from patients with limited patch/plaque lesions, biopsies taken from erythrodermic patients displayed more parakeratosis (p=0.0492) and acanthosis (p=0.0046), less disproportionate epidermotropism, fewer lymphocytes aligned within the basal layer (p=0.0045), fewer hyper-convoluted cells in the epidermis, more dermal hyperconvoluted cells (p=0.0191), more papillary dermal fibrosis (p=0.0002), more prominent teleangiectasias (p=0.0028) and more mitotic figures.
The histologic features of erythrodermic MF and Sézary syndrome are even more subtle than the features of patch and plaque stage MF, thus rendering the histologic diagnosis more difficult. 相似文献
The histologic features of erythrodermic MF and Sézary syndrome are even more subtle than the features of patch and plaque stage MF, thus rendering the histologic diagnosis more difficult. 相似文献
52.
53.
54.
Hyun-Min Shin Chul-Jong Park Jong-Yuk Yi Tae-Yoon Kim Chung-Won Kim 《Pediatric dermatology》1996,13(2):146-147
Abstract: Juvenile xanthogranuloma is a xanthomatous and granulomatous condition that frequently arises before 1 year of age and mainly occurs on the head and trunk. We report a rare solitary juvenile xanthogranuloma on the right palm of a 10-year-old girl, present for one year. This solitary involvement of the palm has been reported only twice before. 相似文献
55.
Eain M. Cornford Deborah Young James W. Paxton 《Cancer chemotherapy and pharmacology》1992,29(6):439-444
Summary The blood-brain barrier penetration of amsacrine and its analogs 9-({2-methoxy-4-[(methylsulfonyl)-amino]phenyl}amino)-,5-dimethyl-4-acridine carboxamide (CI-921) and M-[2-(dimethylamino)ethyl]-acridine-4-carboxamide (AC) was measured in the barbiturate-anesthetized mouse. After intracarotid administration, AC was almost completery extracted (90%) in a single transit through the brain capillaries, whereas CI-921 (20%) and amsacrine (15%) were moderately extracted. AC is retained in the brain; no loss of AC from the brain was apparent at 1, 2, 4, or 8 min after injection. In contrast, after intraportal administration, 75% of the AC, 94% of the CI-921, and 57% of the amsacrine was extracted in a single transit through the hepatic vasculature. Rather than being retained in the mouse liver, these acridine antitumor agents show time-dependent loss (t
1/2=10 min for amsacrine and AC, 24 min for CI-921). We conclude that unlike most antitumor agents, these acridine drugs appear to penetrate the blood-brain barrier readily.This study was supported by the Auckland Medical Research Foundation (New Zealand), by the Medical Research Foundation (New Zealand), by the National Science Foundation (United States/New Zealand Cooperative Science Program), by the United States Veterans Administration, and by NIH grant NS 25554 相似文献
56.
Tetsuji Kai Yang Il Kim Hirokazu Kitamura Katsunori Kawano Seigo Kitano 《Journal of Hepato-Biliary-Pancreatic Surgery》1997,4(4):423-430
There is a growing body of evidence that the cytokine, tumor necrosis factor-α (TNF-ga), plays an important role in the development
of hepatic ischemia/reperfusion injury. We found that the immunosuppressants, cyclosporine-A (CsA), azathioprine, and FK506,
have protective effects on such injury. The purpose of the present study was to elucidate mechanisms involved in these beneficial
effects of the immunosuppressant, CsA, on liver injury following cold preservation and transplantation, with special reference
to the suppression of TNF-α release. Rat livers were stored in Euro-Collins solution (EC) at 4°C for 6h and orthotopically
transplanted. The animals allotted to two groups: group A (untreated controls) and group B (CsA pretreatment of recipients).
CsA (10 mg/kg, p.o.) was given for 3 consecutive days preoperatively. CsA pretreatment of the recipients significantly improved
the 2-week survival rate (0/6 for group A, 3/6 for group B;P<0.05) and this was associated with a significant decrease in serum TNF-α levels 2h posttransplantation (group A, 69.8±15.7
pg/ml; group B, 22.8±6.8; mean±SEM;n=12 each;P<0.05) and amelioration of sinusoidal endothelial injury, assessed by electron microscopy. Plasma endotoxin levels following
reperfusion of the grafts were not altered by the CsA therapy. Morphologically, CsA pretreatment of the recipients did not
alter activation of Kupffer cells. CsA pretreatment of the recipient aids in preventing cold preservation/reperfusion injury
of the liver graft, possibly by modulating effects of TNF-α. 相似文献
57.
PURPOSETo identify changes in the embryology of the hippocampus responsible for its adult anatomy.METHODSTen human fetal specimens ranging from 13 to 24 weeks'' gestational age were examined with MR imaging. Dissections and histologic sections of 10 different specimens of similar ages were compared with MR imaging findings.RESULTSAt 13 to 14 weeks'' gestation, the unfolded hippocampus, on the medial surface of the temporal lobe, surrounds a widely open hippocampal sulcus (hippocampal fissure). At 15 to 16 weeks, the dentate gyrus and cornu ammonis have started to infold. The hippocampal sulcus remains open. The parahippocampal gyrus is larger and more medially positioned. The CA1, CA2, and CA3 fields of the cornu ammonis are arranged linearly. The dentate gyrus has a narrow U shape. By 18 to 20 weeks, the hippocampus begins to resemble the adult hippocampus. The dentate gyrus and cornu ammonis have folded into the temporal lobe. The hippocampus and subiculum approximate each other across a narrow hippocampal sulcus. The CA1-3 fields form an arc and the CA4 field has increased in size within the widened arch of the dentate gyrus.CONCLUSIONMR imaging of fetuses provides a developmental basis for understanding hippocampal anatomy. 相似文献
58.
Rett's syndrome(RS) is a progressive neurodegenerative disorder characterized by exclusive occurrence in females, autistic behavior, dementia, gait ataxia, loss of purposeful use of the hands with stereotypic hand movement, and seizures. Initially RS was considered to be very rare; however, recent reports suggest that the prevalence is considerably higher and occurrence is world-wide. Because the pathophysiological process remains unknown, the diagnosis of RS is based mainly on its characteristic clinical features and course. We experienced two cases of RS which, to our knowledge, are the first reported in Korea. It is quite possible that many patients with RS not yet being diagnosed in Korea. 相似文献
59.
J S Kim 《Stroke; a journal of cerebral circulation》1992,23(7):983-987
BACKGROUND: Although pure sensory stroke is a relatively common lacunar syndrome, the responsible lesions are often unidentified because of their small size. I reported 21 cases of pure sensory stroke in which the lesions could be identified by head computed tomography and/or magnetic resonance imaging and correlated the clinical findings with the radiological lesions. SUMMARY OF REPORT: Eleven patients had thalamic strokes. Lacunes confined to the posterolateral part of the thalamus were found in nine cases, and hemorrhages of relatively large size were found in two. Five patients showed a loss of all sensory modalities, but six with very small lacunes showed minor or restricted sensory changes. Seven patients with lacunes or hemorrhages in the lenticulocapsular region or corona radiata showed abnormalities of spinothalamic tract sensation. Two patients with a small lacune and a hemorrhage in the pontine tegmentum showed a selective sensory deficit of the medial lemniscal type. One patient with a small cortical infarct showed a cortical sensory loss that was preceded by cortical sensory transient ischemic attacks. CONCLUSIONS: Pure sensory stroke can occur with lesions in various areas of the somatosensory system. Hemisensory deficits of all modalities usually are associated with a relatively large lacune or hemorrhage in the lateral thalamus, whereas tract-specific or restricted sensory changes suggest very small strokes in the sensory pathway from the pons to the parietal cortex. 相似文献
60.
J B Sherman M A Alexander D Gomez M Kim P Marole 《Journal of community health nursing》1992,9(3):183-190
The purpose of this study was to implement and evaluate a program for obese school children. A pretest-posttest design was utilized. Data was collected related to weight status, skinfold measurements, self-esteem, and nutritional knowledge. A convenience sample of 26 children, in the fourth to sixth grades, completed this 9-week program. The results indicate that self-esteem increased significantly (p less than .001) between the pretest and posttest interval. Weight status and nutritional knowledge showed no improvement. Exercise was difficult to assess on self-report, therefore no conclusions were were drawn in relation to this variable. Future research will be directed toward refining this intervention program. 相似文献