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961.
962.
The maximal binding capacity (MBC) of nuclear triiodothyronine (T3) receptor sites in rat liver decreases markedly after glucagon administration. Administration of serial doses of glucagon (2.5 microgram/100 g BW) resulted in a 33% decrease in MBC in 3.5 h and MBC was reduced by 45% in 6.25 h. The individual doses used were in the same order of magnitude as those used in the treatment of hypoglycemic human subjects (1.5 microgram/100 g BW). This report presents the first evidence that a peptide hormone can change the number of nuclear T3 receptor sites. The physiological significance of these findings remains to be clarified. 相似文献
963.
R A Bonner 《Postgraduate medicine》1985,77(6):153-164
A mass of evidence favors the concept of euglycemic management of insulin-dependent diabetes, despite significant potential complications. Patients with advanced nephropathy and/or autonomic neuropathy are very poor risks, and infusion therapy does not reverse well-established complications. To well-motivated, educated patients, infusion therapy offers the conveniences of more flexible timing of meals and of having a premeal bolus infusion rather than a premeal injection. With improvement in the technology of continuous glucose monitoring and closed-loop systems, as well as basic improvements in immunologic techniques for islet transplantation, the future may offer a choice of excellent euglycemic therapies for insulin-dependent diabetes. Meanwhile, infusion therapy, which was once only a research tool, is now widely available and is appropriate for near-euglycemic management of diabetes in selected patients. 相似文献
964.
In the presence of atrial fibrillation, the diastolic murmur of mitral stenosis can appear augmented during early systole before the mitral valve closure sound. This phenomenon has previously been thought to be due to increased blood flow velocity across the narrowing mitral valve orifice. We have observed patients in whom the third heart sound (S3) gallop, the diastolic flow murmur of atrial septal defect and mitral insufficiency and the initial muscular component of the first heart sound become more intense during this period with short, critically timed cycle lengths. This phenomenon appears to be neither peculiar to nor indicative of mitral stenosis and is probably a direct result of the initial muscular contraction of an underfilled ventricle. Either the contraction itself or the sudden deceleration of the rapidly moving flow of blood across the atrioventricular orifice may produce the sound. 相似文献
965.
T D Sargent J R Wu J M Sala-Trepat R B Wallace A A Reyes J Bonner 《Proceedings of the National Academy of Sciences of the United States of America》1979,76(7):3256-3260
The rat serum albumin gene has been isolated from a recombinant library containing the entire rat genome cloned in the lambda phage Charon 4A. Preliminary R-loop and restriction analysis has revealed that this gene is split into at least 14 fragments (exons) by 13 intervening sequences (introns), and that it occupies a minimum of 14.5 kilobases of genomic DNA. 相似文献
966.
槐花米的效用,前已言之,据中外化学家研究结果,咸谓含有蘆艼;但据作者初步研究结果,可能非蘆艼,系另一种黄龄素,暂名为槐花甲素,巳志于第一次报告中。本报告专研究第二种无色六面体结晶,据今井和古谷报告,槐花米为酵素水解,得到熔点280°以上物质,此物质据云系蘆艼甙元,占原生药2%,又据刈米、石正和盐见报告,由槐米花中发现三萜类配醣体(triterpenoid)0.4%,水解后得到桦皮脑(Be-tulin)C_(30)H_(50)O_2,葡萄糖和葡萄糖醛酸(glucuronic acid)。此triterpenoid系继色粉 相似文献
967.
968.
Dietary factors and the risk of testicular cancer 总被引:1,自引:0,他引:1
The etiology of testicular cancer (TC) remains largely unknown. Few studies have investigated the role diet may play in the etiology of TC. We report on a hospital-based case-control study of TC and selected nutrients and food groups. Cases included 117 patients with primary, incident TC treated at Roswell Park Cancer Institute between 1982 and 1998. A total of 334 hospital controls were frequency matched on age to cases. Cases were categorized by histology (seminoma, nonseminoma, and mixed germ cell TC), and multinomial logistic regression and unconditional logistic regression were used to compute odds ratios (ORs) and 95% confidence intervals (CIs) comparing each histological type with the controls. For nonseminoma and mixed germ cell TC, vitamin E intake was suggestive of reduced risk (OR = 0.51, 95% CI = 0.15-1.76 and OR = 0.36, 95% CI = 0.01-1.31, respectively); for seminoma, it was suggestive of an increased risk (OR = 2.94, 95% CI = 0.99-8.78). Fat intakes were not associated with nonseminoma or mixed germ cell risk; high saturated, animal, and total fat intakes were suggestive of an increase in risk of seminoma. Overall, diet was not associated with TC. However, risk seemed to differ by histology, suggesting that seminoma, nonseminoma, and mixed germ cell TC may have different etiologies. We suggest that future investigations should continue to stratify cases by histology. 相似文献
969.
PP Varma Tapan Sinha D Batura R Malik RSV Kumar GS Chopra HS Gill 《Medical Journal Armed Forces India》2002,58(3):196-200
31 renal transplant procedures have been performed at this centre. Renal donors were father in 4, mother in 4, brother in 12, sister in 4, brother-in-law in 1 and wives in 6 cases. Median age of recipients and donors was 35.2 years (20-55) and 38.3 years (24-60) respectively. After a mean follow up of 15.7 months (2-40), graft survival was 96.7% and patient survival 90-3%. Three patients (9.6%) required surgical re-exploration, one each for, peri-graft haematoma, arterial kink and graft artery thrombosis. 6 patients (19.3%) required anti rejection therapy with resultant complete normalisation of graft functions. Medical complications noted were post transplant diabetes mellitus in 6 (19.3%), azathihoprine induced bone marrow suppression in 1(3.2%), tuberculosis in 2 (6.4%), post transplant erythrocytosis in 2 (6.4%) and recurrent urinary tract infection (UTI) in one (3.2%) patients. 3 patients (9.6%) died with functioning graft, one due to lung infection and the other due to haemorrahagic pancreatitis and third due to infective endocarditis.Key Words: Post-transplant complications, Renal Transplantation 相似文献
970.
Howlett AC Barth F Bonner TI Cabral G Casellas P Devane WA Felder CC Herkenham M Mackie K Martin BR Mechoulam R Pertwee RG 《Pharmacological reviews》2002,54(2):161-202
Two types of cannabinoid receptor have been discovered so far, CB(1) (2.1: CBD:1:CB1:), cloned in 1990, and CB(2) (2.1:CBD:2:CB2:), cloned in 1993. Distinction between these receptors is based on differences in their predicted amino acid sequence, signaling mechanisms, tissue distribution, and sensitivity to certain potent agonists and antagonists that show marked selectivity for one or the other receptor type. Cannabinoid receptors CB(1) and CB(2) exhibit 48% amino acid sequence identity. Both receptor types are coupled through G proteins to adenylyl cyclase and mitogen-activated protein kinase. CB(1) receptors are also coupled through G proteins to several types of calcium and potassium channels. These receptors exist primarily on central and peripheral neurons, one of their functions being to inhibit neurotransmitter release. Indeed, endogenous CB(1) agonists probably serve as retrograde synaptic messengers. CB(2) receptors are present mainly on immune cells. Such cells also express CB(1) receptors, albeit to a lesser extent, with both receptor types exerting a broad spectrum of immune effects that includes modulation of cytokine release. Of several endogenous agonists for cannabinoid receptors identified thus far, the most notable are arachidonoylethanolamide, 2-arachidonoylglycerol, and 2-arachidonylglyceryl ether. It is unclear whether these eicosanoid molecules are the only, or primary, endogenous agonists. Hence, we consider it premature to rename cannabinoid receptors after an endogenous agonist as is recommended by the International Union of Pharmacology Committee on Receptor Nomenclature and Drug Classification. Although pharmacological evidence for the existence of additional types of cannabinoid receptor is emerging, other kinds of supporting evidence are still lacking. 相似文献