全文获取类型
收费全文 | 2210篇 |
免费 | 239篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 83篇 |
妇产科学 | 48篇 |
基础医学 | 297篇 |
口腔科学 | 45篇 |
临床医学 | 227篇 |
内科学 | 423篇 |
皮肤病学 | 26篇 |
神经病学 | 154篇 |
特种医学 | 92篇 |
外国民族医学 | 1篇 |
外科学 | 467篇 |
综合类 | 64篇 |
一般理论 | 1篇 |
预防医学 | 187篇 |
眼科学 | 86篇 |
药学 | 159篇 |
中国医学 | 4篇 |
肿瘤学 | 76篇 |
出版年
2021年 | 30篇 |
2019年 | 20篇 |
2018年 | 24篇 |
2017年 | 28篇 |
2016年 | 26篇 |
2015年 | 38篇 |
2014年 | 49篇 |
2013年 | 56篇 |
2012年 | 82篇 |
2011年 | 85篇 |
2010年 | 47篇 |
2009年 | 50篇 |
2008年 | 73篇 |
2007年 | 88篇 |
2006年 | 93篇 |
2005年 | 69篇 |
2004年 | 71篇 |
2003年 | 64篇 |
2002年 | 77篇 |
2001年 | 69篇 |
2000年 | 79篇 |
1999年 | 61篇 |
1998年 | 39篇 |
1997年 | 32篇 |
1996年 | 44篇 |
1995年 | 27篇 |
1994年 | 24篇 |
1993年 | 31篇 |
1992年 | 39篇 |
1991年 | 56篇 |
1990年 | 52篇 |
1989年 | 66篇 |
1988年 | 43篇 |
1987年 | 39篇 |
1986年 | 59篇 |
1985年 | 49篇 |
1984年 | 43篇 |
1983年 | 46篇 |
1982年 | 33篇 |
1981年 | 23篇 |
1980年 | 21篇 |
1979年 | 35篇 |
1978年 | 28篇 |
1977年 | 31篇 |
1976年 | 23篇 |
1975年 | 27篇 |
1974年 | 20篇 |
1973年 | 35篇 |
1968年 | 19篇 |
1967年 | 19篇 |
排序方式: 共有2454条查询结果,搜索用时 0 毫秒
101.
Swerdlow RH Parks JK Cassarino DS Binder DR Bennett JP Di Iorio G Golbe LI Parker WD 《Experimental neurology》2001,169(2):479-485
Complex I activity is reduced in cytoplasmic hybrid (cybrid) cell lines that contain mitochondrial DNA (mtDNA) from sporadic Parkinson's disease (PD) patients. This implies that mtDNA aberration occurs in sporadic PD. To assess the integrity of mtDNA in autosomal dominant PD arising from mutation of the alpha-synuclein gene, we transferred mitochondrial genes from PD-affected members of the Italian-American Contursi kindred to cells previously depleted of their endogenous mtDNA. Unlike cybrid cell lines expressing mtDNA from persons with sporadic or maternally inherited PD, the resultant Contursi cybrid lines did not manifest complex I deficiency, indicating that in Contursi PD mtDNA integrity is relatively preserved. Compared to control cybrids, however, Contursi cybrid lines did show some evidence of oxidative stress. For reasons that are unclear, at least a limited amount of mtDNA damage may nevertheless develop in PD patients with alpha-synuclein mutation. 相似文献
102.
Fifty seven children with thoracic empyema (37 boys and 20 girls) aged less than 12 years were seen at the University of Port Harcourt Teaching Hospital between January 1989 and December 1991. Staphylococcus aureus was the most common organism isolated from the pus of these patients (36 (63%) patients). Pseudomonas aeruginosa, the next most common organism, was isolated in 10 (18%) patients. The most common symptoms at presentation were acute illness with fever and cough (51 (89%) patients). All the patients were treated with closed intercostal tube drainage and appropriate antibiotics. Decortication was resorted to in only one patient. There were two deaths and the overall survival rate was 97%. 相似文献
103.
104.
“True agonadism”: A misnomer? 总被引:1,自引:0,他引:1
G A Parks K W Dumars G A Limbeck W L Quinlivan M I New 《The Journal of pediatrics》1974,84(3):375-380
105.
106.
107.
Fetal and postnatal testis shows immunoprivilege as donor tissue 总被引:5,自引:0,他引:5
We evaluated the immunogenicity of the testis by transplanting adult, postnatal, and fetal rat testicular tissue into outbred adult female and male rats for 10 days. Testis grafts were evaluated morphometrically and histologically, and selectively compared to renal grafts previously reported in part. Testis grafts from days 15 to 21 of gestation, and from three, nine, 12 and 15 days after birth showed an overall increase in growth, with maintenance of architecture and minimal lymphocytic infiltrate. In contrast, only fetal renal tissue from days 15 to 17 demonstrated an increase in growth with maintenance of architecture and minimal lymphocytic infiltrate; grafts from later in gestation grew only slightly and showed progressive deterioration in architecture with an increasing lymphocytic infiltrate. Fifteen day fetal testis grafts were also implanted for longer intervals up to 45 days. The fetal testis grafts implanted for 20 and 30 days showed an increase in size with maintenance of architecture and minimal lymphocytic infiltrate. The observed fetal and postnatal testis growth in the non-immunosuppressed adult host makes compelling further studies directed at determining those factors contributing to the decreased immunogenicity of this organ. 相似文献
108.
RW Parks FRCS 《International journal of clinical practice》1996,50(2):118-119
SUMMARY Gastrocolic fistula is most often related to malignancy or previous gastric surgery. It is an uncommon complication of benign gastric ulceration in patients who have not had a previous operation. Benign gastrocolic fistula associated with peritonitis is extremely rare — this case is only the fourth ever reported. The patient presented with an acute abdomen, and subsequent investigations demonstrated a gastrocolic fistula of benign aetiology. 相似文献
109.
We have used an immunoaffinity system whereby immunoglobulin from patients with prostatic carcinoma was coupled to solid phase protein A; the immobilized IgG was subsequently exposed to radiolabeled antigen from autochthonous or allogeneic primary tumor extracts or to radiolabeled antigen from a nude mouse-supported prostatic carcinoma cell line. Material specifically bound by prostatic carcinoma patient immune IgG was quantitatively eluted from the immunoadsorbent and characterized with regard to molecular weight. Sequential adsorption analyses of patient sera with normal human tissue pools, normal prostatic tissue, prostatic carcinoma tissue, and tissue from other urogenital malignancies has allowed a definition of those antigenic specificities relevant in the immunobiology of prostatic carcinoma. The patient humoral response was observed to be directed primarily toward a complex array of antigens representing normal human tissue components; serorecognition of prostate tumor associated antigens was discernible from that of common tissue antigens only after rigorous adsorption analyses. Preliminary results indicate that the prostatic cancer patient humoral antibody response may be directed toward either altered histocompatibility complex antigens or toward antigens physically associated with histocompatibility complex antigens. 相似文献
110.
Judith D. Levich William O. Weigle D. Elliot Parks 《European journal of immunology》1984,14(12):1073-1079
Suppressor T cell (Ts) lines have been generated and maintained in culture for over one year. Cells from these lines suppress proliferation by primed lymph node cells and antibody production by primed spleen cells. Ts were originally obtained from either spleens of mice rendered tolerant to human gamma globulin (HGG) or short-term cultures of normal spleen cells. Ts from these two sources have previously been shown to exhibit antigen specificity in that only HGG-specific immune responses were suppressed. Prolonged culture of Ts, however, leads to 2 events: (a) an enrichment for suppressive activity in the cultures; and (b) a polyclonal activation of Ts which is demonstrated by the acquired ability of Ts cell lines to regulate responses to antigens other than HGG. Ts cell lines still contain HGG-specific Ts which can be isolated by their capacity to bind to HGG-coated plates. Only HGG-specific immune responses are suppressed by the HGG-binding Ts. 相似文献