全文获取类型
收费全文 | 6977篇 |
免费 | 412篇 |
国内免费 | 43篇 |
专业分类
耳鼻咽喉 | 68篇 |
儿科学 | 262篇 |
妇产科学 | 115篇 |
基础医学 | 990篇 |
口腔科学 | 141篇 |
临床医学 | 728篇 |
内科学 | 1347篇 |
皮肤病学 | 158篇 |
神经病学 | 637篇 |
特种医学 | 482篇 |
外科学 | 705篇 |
综合类 | 276篇 |
一般理论 | 5篇 |
预防医学 | 547篇 |
眼科学 | 158篇 |
药学 | 564篇 |
1篇 | |
中国医学 | 2篇 |
肿瘤学 | 246篇 |
出版年
2022年 | 109篇 |
2021年 | 220篇 |
2020年 | 80篇 |
2019年 | 132篇 |
2018年 | 180篇 |
2017年 | 118篇 |
2016年 | 154篇 |
2015年 | 141篇 |
2014年 | 185篇 |
2013年 | 303篇 |
2012年 | 266篇 |
2011年 | 231篇 |
2010年 | 222篇 |
2009年 | 194篇 |
2008年 | 191篇 |
2007年 | 222篇 |
2006年 | 226篇 |
2005年 | 204篇 |
2004年 | 172篇 |
2003年 | 160篇 |
2002年 | 163篇 |
2001年 | 137篇 |
2000年 | 164篇 |
1999年 | 161篇 |
1998年 | 133篇 |
1997年 | 136篇 |
1996年 | 131篇 |
1995年 | 98篇 |
1994年 | 111篇 |
1993年 | 107篇 |
1992年 | 119篇 |
1991年 | 101篇 |
1990年 | 103篇 |
1989年 | 134篇 |
1988年 | 107篇 |
1987年 | 108篇 |
1986年 | 116篇 |
1985年 | 95篇 |
1984年 | 109篇 |
1983年 | 65篇 |
1982年 | 80篇 |
1981年 | 68篇 |
1980年 | 82篇 |
1979年 | 56篇 |
1977年 | 62篇 |
1976年 | 62篇 |
1975年 | 62篇 |
1965年 | 56篇 |
1964年 | 51篇 |
1960年 | 68篇 |
排序方式: 共有7432条查询结果,搜索用时 15 毫秒
51.
Application of an intragenic genomic probe to genetic counselling for haemophilia B in the west of Scotland. 总被引:1,自引:1,他引:1 下载免费PDF全文
J M Connor A F Pettigrew I M Hann C D Forbes G D Lowe N A Affara 《Journal of medical genetics》1985,22(6):441-446
Total ascertainment revealed 28 families with haemophilia B in the west of Scotland (prevalence 1/26 870 males). In 12 of these families more than one person was affected and 26 living obligate carriers were identified and tested. Of these, 42% were heterozygous for a DNA polymorphism recognised by a factor IX genomic probe. No recombination was observed in 11 phase known and four phase unknown informative meioses. Definitive genetic counselling was possible for 14 of 42 females at risk, 11 could not be traced, in 10 the probe was not informative, and in seven paternal absence prevented interpretation. Linkage disequilibrium was apparent for this restriction fragment length polymorphism and haemophilia B in the west of Scotland. 相似文献
52.
53.
We have studied trisomy 12 in chronic lymphocytic leukemia (CLL) by fluorescence in situ hybridization (FISH) with an -satellite centromeric probe for chromosome 12 on both dividing and non-dividing cells. Trisomy for chromosome 12 was demonstrated in four of these patients (15.3%) using FISH on interphase cells. The percentage of trisomic cells ranged from 10% to 65% of nuclei. The hybridization signals in the trisomic and disomic nuclei were of a broadly similar size and nature. Interestingly, three of the remaining CLL patients, who exhibited disomy for chromosome 12, showed a marked difference in size of the hybridization signals in interphase nuclei. This was also demonstrated in metaphase spreads. In addition, metaphase FISH studies revealed a supernumerary marker chromosome in three out of 26 patients with CLL. 相似文献
54.
Antimicrobial activity of various immunomodulators: independence from normal levels of circulating monocytes and natural killer cells. 总被引:1,自引:2,他引:1 下载免费PDF全文
The effects of 89Sr treatment on the natural host resistance of CD-1 mice and the enhancement of resistance by immunomodulators to infection with Listeria monocytogenes or herpes simplex virus type 2 (HSV-2) were determined. In the CD-1 mouse, single-dose treatment with 89Sr caused a profound decrease in the number of circulating monocytes (Mo), lymphocytes, and polymorphonuclear leukocytes (PMN) within 1 week. There was also marked functional impairment of the Mo inflammatory response, as well as markedly decreased spontaneous and activatable cytotoxicity by splenic natural killer (NK) cells. Despite this profound cellular suppression, there was no significant change in natural resistance of CD-1 mice to L. monocytogenes or HSV-2 infection. Furthermore, prophylactic treatment of mice with the biologic immunomodulator Corynebacterium parvum or the synthetic immunomodulators maleic anhydride-divinyl ether or avridine in liposomes resulted in comparable enhancement of resistance in 89Sr-treated and normal mice. These data indicate that natural and immunomodulator-enhanced resistance of CD-1 mice to microbial infections do not depend on normal levels of Mo, PMN, or NK cells. The resistance enhancement may rely on activated tissue macrophages (M phi). In contrast to the early changes in circulating leukocytes, the resident peritoneal cell populations were not markedly altered until after day 30. There then was a distinct decline in lymphocytes and a gradual decline in M phi; the change in M phi was apparently due to the lack of an age-related increase in the peritoneal M phi population in 89Sr-treated mice in comparison with a slight increase in resident M phi in normal mice. After CD-1 mice were treated with 89Sr, the number of PMN and the function of NK cells generally recovered by about day 50 and was followed by partial recovery of circulating Mo, unless a second dose of 89Sr was administered. 相似文献
55.
56.
Neurobehavioral Symptoms and Family Functioning in Traumatically Brain-Injured Adults 总被引:4,自引:0,他引:4
Kevin N. Groom Terry G. Shaw Mary E. OConnor Nicole I. Howard Angela Pickens 《Archives of clinical neuropsychology》1998,13(8):695-711
Traumatic brain injury (TBI) often results in a myriad of symptoms across physical, cognitive, and neurobehavioral domains. Despite inherent limitations associated with physical or cognitive impairments, the extant literature suggests that neurobehavioral symptoms tend to be the most distressing symptoms for the family and are more strongly related to poor outcome for the patient. The Neuropsychology Behavior and Affect Profile (NBAP) along with the General Functioning subscale of the Family Assessment Device (FAD-GF) and the Perceived Stress Scale were administered to 153 family members of persons who had sustained a TBI. The results provide new normative data and statistical support for the NBAP as a promising measure of neurobehavioral symptomatology following TBI. The correlation of.54 (p <.01) between FAD-GF and Full Scale NBAP scores provides powerful support for the hypothesis that family dysfunction is related to the presence of neurobehavioral symptoms in the patient. NBAP domains of Depression, Inappropriateness, Pragnosia, and Indifference appear most strongly related to family functioning and also bear a significant relationship to caregiver stress level and patient unemployment, whereas injury severity had little impact on either family functioning or neurobehavioral symptoms. The findings reinforce the significance of neurobehavioral symptoms and fortify their proposed link to family dysfunction post-TBI. 相似文献
57.
R Patel G Connor D R Patel A Soriano D Najera 《International archives of allergy and applied immunology》1986,79(2):182-187
Determination of T lymphocyte subsets using monoclonal antibodies revealed a deficiency of suppressor cells and an elevated helper:suppressor T cell ratio in 7 patients with untreated idiopathic immune complex glomerulonephritis and nephrotic syndrome. Possible pathogenetic mechanisms of immunoregulatory cell imbalance and their implications specifically in reference to idiopathic glomerulonephritis are discussed. 相似文献
58.
Linkage exclusion and mutational analysis of the noggin gene in patients with fibrodysplasia ossificans progressiva (FOP) 总被引:1,自引:0,他引:1
Xu MQ Feldman G Le Merrer M Shugart YY Glaser DL Urtizberea JA Fardeau M Connor JM Triffitt J Smith R Shore EM Kaplan FS 《Clinical genetics》2000,58(4):291-298
Fibrodysplasia ossificans progressiva (FOP) is an extremely rare and disabling genetic disorder characterized by congenital malformation of the great toes and by progressive heterotopic endochondral ossification in predictable anatomical patterns. Although elevated levels of bone morphogenetic protein 4 (BMP4) occur in lymphoblastoid cells and in lesional cells of patients with FOP, mutations have not been identified in the BMP4 gene, suggesting that the mutation in FOP may reside in a BMP4-interacting factor or in another component of the BMP4 pathway. A powerful antagonist of BMP4 is the secreted polypeptide noggin. A recent case report described a heterozygous 42-bp deletion in the protein-coding region of the noggin gene in a patient with FOP. In order to determine if noggin mutations are a widespread finding in FOP, we examined 31 families with 1 or more FOP patients. Linkage analysis with an array of highly polymorphic microsatellite markers closely linked to the noggin gene was performed in four classically-affected multigenerational FOP families and excluded linkage of the noggin locus to FOP (the multipoint lod score was -2 or less throughout the entire range of markers). We sequenced the noggin gene in affected members of all four families, as well as in 18 patients with sporadic FOP, and failed to detect any mutations. Single-strand conformation polymorphism (SSCP) analysis of 4 of these patients plus an additional 9 patients also failed to reveal any mutations. Among the samples analyzed by SSCP and DNA sequencing was an independently obtained DNA sample from the identical FOP patient previously described with the 42-bp noggin deletion; no mutation was detected. Examination of the DNA sequences of 20 cloned noggin PCR products, undertaken to evaluate the possibility of a somatic mutation in the noggin gene which could be carried by a small subset of white blood cells, also failed to detect the presence of the reported 42-bp deletion. We conclude that mutations in the coding region of noggin are not associated with FOP. 相似文献
59.
Beta-sitosterolemia and xanthomatosis. 总被引:3,自引:0,他引:3
R S Shulman A K Bhattacharyya W E Connor D S Fredrickson 《The New England journal of medicine》1976,294(9):482-483
60.
Increase in ferric and ferrous iron in the rat hippocampus with time after kainate-induced excitotoxic injury 总被引:4,自引:0,他引:4
Wang XS Ong WY Connor JR 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,143(2):137-148
The present study aimed to elucidate the distribution of ferric and ferrous iron in the hippocampus after kainate-induced neuronal injury. A modified Perl's or Turnbull's blue histochemical stain was used to demonstrate Fe3+ and Fe2+ respectively. Very light staining for iron was observed in the hippocampus, in normal or saline-injected rats and 1-day post-kainate-injected rats. At 1 week postinjection, a number of Fe3+-positive, but very few Fe2+-positive, cells were present, in the degenerating CA fields. At 1 month postinjection, large numbers of Fe3+-positive glial cells, and some Fe2+-positive blood vessels, were observed. At 2 months postinjection, large numbers of Fe3+- and Fe2+-positive glial cells were present. The labeled cells had light and electron microscopic features of oligodendrocytes, and were double labeled with CNPase, a marker for oligodendrocytes. The observation of an increasing number of Fe3+- and Fe2+-positive cells in the degenerating hippocampus with time is consistent with the results of a nuclear microscopic study, in which an increasing amount of iron was detected in the degenerating hippocampus after kainate injection. In addition, the present study showed a shift in the oxidation state of the accumulated iron, with more cells becoming Fe2+ at a late stage. A possible consequence of the high amounts of Fe2+ in the hippocampus after kainate injection is that it could promote free radical damage in the lesioned areas. 相似文献