全文获取类型
收费全文 | 1081387篇 |
免费 | 72095篇 |
国内免费 | 1393篇 |
专业分类
耳鼻咽喉 | 15069篇 |
儿科学 | 34778篇 |
妇产科学 | 28679篇 |
基础医学 | 154314篇 |
口腔科学 | 29821篇 |
临床医学 | 95374篇 |
内科学 | 205134篇 |
皮肤病学 | 24559篇 |
神经病学 | 82002篇 |
特种医学 | 43183篇 |
外国民族医学 | 201篇 |
外科学 | 164132篇 |
综合类 | 21744篇 |
现状与发展 | 1篇 |
一般理论 | 263篇 |
预防医学 | 74779篇 |
眼科学 | 24650篇 |
药学 | 86621篇 |
7篇 | |
中国医学 | 2819篇 |
肿瘤学 | 66745篇 |
出版年
2019年 | 7880篇 |
2018年 | 11446篇 |
2017年 | 9011篇 |
2016年 | 10223篇 |
2015年 | 11397篇 |
2014年 | 15467篇 |
2013年 | 22434篇 |
2012年 | 30900篇 |
2011年 | 32689篇 |
2010年 | 19180篇 |
2009年 | 17983篇 |
2008年 | 30250篇 |
2007年 | 32424篇 |
2006年 | 33023篇 |
2005年 | 31356篇 |
2004年 | 30035篇 |
2003年 | 28855篇 |
2002年 | 27812篇 |
2001年 | 60193篇 |
2000年 | 61632篇 |
1999年 | 51056篇 |
1998年 | 12549篇 |
1997年 | 11061篇 |
1996年 | 11080篇 |
1995年 | 10377篇 |
1994年 | 9388篇 |
1993年 | 8899篇 |
1992年 | 37879篇 |
1991年 | 36376篇 |
1990年 | 35813篇 |
1989年 | 34394篇 |
1988年 | 30952篇 |
1987年 | 30063篇 |
1986年 | 28289篇 |
1985年 | 26525篇 |
1984年 | 19231篇 |
1983年 | 16162篇 |
1982年 | 8855篇 |
1979年 | 17077篇 |
1978年 | 11429篇 |
1977年 | 10257篇 |
1976年 | 8860篇 |
1975年 | 10089篇 |
1974年 | 11686篇 |
1973年 | 11302篇 |
1972年 | 10799篇 |
1971年 | 10120篇 |
1970年 | 9286篇 |
1969年 | 8967篇 |
1968年 | 7943篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
951.
V M Buianov S S Maskin A N Kovalev A Ia Korovin N Iu Shestakov K E Riabtsev 《Klinichna khirurhiia / Ministerstvo okhorony zdorov'ia Ukra?ny, Naukove tovarystvo khirurhiv Ukra?ny》1990,(1):1-3
Comparative analysis of 3707 operations on the organs of the abdominal cavity has shown the significant advantage of the suggested by the authors method for intraoperative wound protection with latex rubber in combination with placing the longitudinal removable sutures over the subcutis and skin, and dressing-free management of the wounds in prophylaxis of the postoperative purulent wound complications. After 310 operations of different contamination degree performed with the use of the given method, no suppuration of the operative wounds was noted. 相似文献
952.
Among the new techniques available for CyA monitoring, the FPIA offers the advantages of rapidity and simplicity. The present communication assesses the technical performance of this test in comparison with a 3H tracer-based PC-RIA for serum CyA levels using 971 samples obtained during the first 6 posttransplant months from 14 kidney transplant recipients. The FPIA evaluation included verification of CyA concentrations in manufacturer-supplied calibrators and controls by reference methods, determination of intraassay/interassay precision and accuracy, feasibility of specimen dilution and assessed assay sensitivity, and range of linearity. Comparison of FPIA with PC-RIA indicated that trough samples, when assessed by FPIA, averaged 1.3-fold greater than the PC-RIA, whereas non-trough FPIA measurements indicated similarity between the two methods. Although the two assays showed similar trends in most renal transplant recipients, two subjects demonstrated discrepancies, presumably reflecting the differing specificities of the polyclonal antibodies used in each assay. Thus, the FPIA appears to be a useful addition to CyA monitoring technology. 相似文献
953.
The authors present a case of intrathoracic meningocele associated with neurofibromatosis. Computed tomography with metrizamide myelography proved valuable in locating the lesion, thus facilitating surgical intervention. With the preoperative diagnosis established and the severity of the meningocele known, the surgeons safely employed a subpleural approach at thoracotomy. 相似文献
954.
Detection of nephritogenic antigen from the Lewis rat renal tubular basement membrane 总被引:1,自引:0,他引:1
H Yoshida Y Wakashin S Ueda R Azemoto K Iesato S Yamamoto T Mori M Ogawa Y Mori M Wakashin 《Kidney international》1990,37(5):1286-1294
Immunopathogenicity of trypsin-solubilized or non-solubilized renal tubular basement membrane (TBM) of the Lewis (LEW) rat was investigated. Autoimmune tubulointerstitial nephritis (TIN) was induced in BALB/c mice by immunization with trypsin-solubilized LEW rat TBM, while immunization with non-solubilized TBM did not produce the disease. Based on this preliminary experiment we studied the characterization of immunogenic and nephritogenic TBM antigen of the LEW rat. TIN was characterized by severe mononuclear cell infiltrates with multi-nucleated giant cells in the interstitium, tubular destruction and intensive IgG and C3 deposits along the TBM. Anti-TBM antisera and eluate from the nephritic mouse kidneys reacted with the TBM of normal LEW rat kidney by immunofluorescence. LEW rat TBM was also detected immunofluorescently by using antisera from BALB/c mice immunized with autologous trypsin-solubilized TBM. A competitive inhibition test revealed a higher titer of anti-TBM antibody in the eluate than in the adsorption-treated antisera per microgram IgG. Immunoblotting showed one reactive band with a molecular weight of 45,000 daltons, and the blotting patterns in tryptic TBM of the Brown Norway (BN) and LEW rats appeared similar. Amino acid analysis of nephritogenic LEW rat tryptic TBM showed that it contained no hydroxyproline and hydroxylysine, suggesting that this TBM preparation was not collagenous. These findings suggest that tryptic digestion contributes to the release of nephritogenic antigen from the LEW rat TBM and that this antigen system might participate in the immune system involved in the anti-TBM associated TIN that is well known to be induced by non-digested TBM of TBM antigen positive animals. 相似文献
955.
Three xenografts established from three patients with anaplastic thyroid carcinoma were investigated for their biological characteristics and chemosensitivity. The histological and immunohistochemical findings of these tumors were almost the same as those of the original tumors. Although the growth rate of each xenograft was constant, the tumor doubling time varied from 4.8 per 9.0 days, and the labeling indexes, determined using bromodeoxyuridine pulse labeling, varied from 11.4 to 25.1 per cent. The chemosensitivity tests were performed according to the Battelle Columbus Laboratories Protocol, with adriamycin, cyclophosphamide, cisplatin, mitomycin C and tegafur administered intraperitoneally to tumor-bearing nude mice in maximum tolerable doses. Tumors with slower growth rates tended to be sensitive to more drugs. Furthermore, cyclophosphamide showed antitumor effects against all the tumors tested. Although previous treatments of the original tumors may have affected the results, our results suggest that a more suitable chemotherapy for anaplastic thyroid carcinoma could be developed. 相似文献
956.
957.
J S Wayne D Amiel M K Kwan S L Woo A Fierer M H Meyers 《Acta orthopaedica Scandinavica》1990,61(6):539-545
We have studied long-term (to 60 days) effects of 4 degrees C storage in culture media on the histologic, mechanical, and chemical properties of the cartilage from osteochondral shell allografts from the dog. The structural integrity of the cartilage matrix was intact up to 60 days of storage, for the mechanical properties represented by the aggregate modulus and apparent permeability remained normal. These data are supported by normal safranin-O staining as well as normal glycosaminoglycan content and total collagen concentration. However, chondrocyte viability, as assessed by 35SO4 uptake and hematoxylin and eosin preparations, decreased dramatically with time. We believe that the longer storage to 60 days is not indicated, unless conditions can be modified to maintain cell viability. 相似文献
958.
INLANDER, CHARLES B., LEVIN, LOWELL B., AND WEINER, E.D. Medicine on Trial: The Appalling Story of Medical Ineptitude and the Arrogance that Overlooks It. 相似文献
959.
Stimulation of tear secretion by topical agents that increase cyclic nucleotide levels 总被引:1,自引:0,他引:1
J P Gilbard S R Rossi K G Heyda D A Dartt 《Investigative ophthalmology & visual science》1990,31(7):1381-1388
The authors examined the effect of topical application of agents known to increase cyclic nucleotide levels on tear secretion by accessory lacrimal gland tissue in their rabbit model for keratoconjunctivitis sicca (KCS). Tear secretion was studied by changes in tear film osmolarity and tear volume caused by application of the agents relative to application of isotonic buffer solution alone. A decrease in tear film osmolarity or increase in tear volume was interpreted as an increase in tear secretion. Irritative stimulation was distinguished from pharmacologic stimulation by the prior use of topical proparacaine. The following agents significantly decreased tear film osmolarity and increased tear volume: vasoactive intestinal peptide (2 X 10(-8) to 2 X 10(-6) M); three pro-opiomelanocortin fragments alpha-, beta-, and gamma-melanocyte stimulating hormone at 10(-4), 10(-3), and 10(-3) M, respectively; the permeable cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) analogs 8-Br cAMP (0.3-3.0 X 10(-3) M) and 8-Br cGMP (1.0-10.0 X 10(-3) M); and the cyclic nucleotide phosphodiesterase inhibitor 1-isobutyl-3-methyl xanthine (0.3-3.0 X 10(-3) M). Forskolin (2 X 10(-4) M), which activates the catalytic subunits of adenyl cyclase, increased tear volume significantly. Secretin, adrenocorticotropic hormone, and pilocarpine were ineffective. The authors conclude that agents that increase either cAMP or cGMP levels pharmacologically stimulated tear secretion when applied topically to rabbit eyes with surgically induced KCS. 相似文献
960.
The effect of ethylene glycol on rat hepatic microsomal cytochrome P-450 was studied in vitro and in vivo. The destruction of cytochrome P-450 was not seen in vitro. The addition of 1 mM NADPH also did not change. When ethylene glycol was added to drinking water at a concentration of 1.0% for 7 days, there was no change in the contents of microsomal protein, cytochrome P-450, b5 and heme. While NADPH-cytochrome C reductase activity of the exposed group did not change, NADH-ferricyanide reductase activity increased significantly. 相似文献