全文获取类型
收费全文 | 5678篇 |
免费 | 678篇 |
国内免费 | 55篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 265篇 |
妇产科学 | 267篇 |
基础医学 | 874篇 |
口腔科学 | 135篇 |
临床医学 | 587篇 |
内科学 | 1000篇 |
皮肤病学 | 167篇 |
神经病学 | 527篇 |
特种医学 | 262篇 |
外科学 | 636篇 |
综合类 | 152篇 |
一般理论 | 5篇 |
预防医学 | 646篇 |
眼科学 | 151篇 |
药学 | 355篇 |
1篇 | |
中国医学 | 24篇 |
肿瘤学 | 343篇 |
出版年
2021年 | 68篇 |
2020年 | 37篇 |
2019年 | 65篇 |
2018年 | 92篇 |
2017年 | 87篇 |
2016年 | 94篇 |
2015年 | 85篇 |
2014年 | 121篇 |
2013年 | 162篇 |
2012年 | 205篇 |
2011年 | 206篇 |
2010年 | 161篇 |
2009年 | 173篇 |
2008年 | 212篇 |
2007年 | 268篇 |
2006年 | 246篇 |
2005年 | 199篇 |
2004年 | 192篇 |
2003年 | 192篇 |
2002年 | 208篇 |
2001年 | 199篇 |
2000年 | 197篇 |
1999年 | 192篇 |
1998年 | 139篇 |
1997年 | 128篇 |
1996年 | 111篇 |
1995年 | 91篇 |
1994年 | 82篇 |
1993年 | 98篇 |
1992年 | 140篇 |
1991年 | 121篇 |
1990年 | 132篇 |
1989年 | 140篇 |
1988年 | 116篇 |
1987年 | 135篇 |
1986年 | 114篇 |
1985年 | 117篇 |
1984年 | 98篇 |
1983年 | 88篇 |
1982年 | 64篇 |
1981年 | 44篇 |
1980年 | 59篇 |
1979年 | 68篇 |
1978年 | 57篇 |
1977年 | 57篇 |
1976年 | 49篇 |
1975年 | 46篇 |
1974年 | 53篇 |
1973年 | 53篇 |
1972年 | 46篇 |
排序方式: 共有6411条查询结果,搜索用时 31 毫秒
21.
Satoshi Hisano Winnie Chan Kay Latta Richard J Krieg Jr. James CM Chan 《Clinical and experimental nephrology》1997,1(3):179-186
Growth retardation is a major complication in children with uremia. Protein restriction, calorie deficit, metabolic acidosis,
renal osteodystrophy, and endocrinologic disturbances contribute to the growth failure. The effect of these factors on growth
retardation can be attenuated in part by therapy with vitamin D metabolites, adequate nutrition, alkalization, and dialysis.
Linear growth in children with uremia is markedly retarded despite normal or increased levels of circulating serum growth
hormone. An increased growth hormone level in children with uremia is due to normal growth hormone secretion from the pituitary
gland and impaired growth hormone clearance in the kidney. However, the elevated growth hormone level does not lead to a commensurate
rise in serum insulin-like growth factor I (IGF-I); the serum IGF-I level is decreased or normal in relation to the degree
of renal failure. This discrepancy suggests growth hormone resistance in the liver in uremia. Recent molecular techniques
open a new era in studying the gene expression for growth hormone or IGF-I. There is no doubt today that growth hormone treatment
has the beneficial effect of growth promotion in children with uremia, which also suggests endogenous growth hormone resistance
in target organs or target cells in uremia. 相似文献
22.
Mark R. Beauchamp Albert V. Carron Serena McCutcheon Oliver Harper 《Annals of behavioral medicine》2007,33(2):200-206
Background: A growing body of research suggests that older exercisers prefer to exercise alone rather than in group-based settings. One
limitation of these studies, however, has been that researchers have failed to take into account the age-related characteristics
of groups when asking adults about their preferences for exercise settings.Purpose: The overall purpose of this study was to examine the exercise preferences of 947 adults for involvement in standard exercise
classes populated by participants from various categories across the age spectrum.Results: The results revealed that when faced with the prospect of exercising with considerably older or younger exercisers, participants
found such an exercise context to be largely unappealing. However, in accordance with the basic tenets of self-categorization
theory, the results revealed that older and younger adults alike express a positive preference for exercising in standard
exercise classes comprised of similarly aged participants.Conclusions: The findings of this study challenge a growing call for exercise interventions for older adults to be primarily directed
at the individual-level, and suggest that group-related intervention strategies may indeed be attractive to older exercisers. 相似文献
23.
Caporale CM Capasso M Lucani M Gandolfi P De Angelis MV Di Muzio A Caporale V Uncini A . 《Journal of the peripheral nervous system : JPNS》2004,9(2):114-115
Campylobacter jejuni (C. jejunj) infection is the most common antecedent in the axonal variant of Guillain‐Barré syndrome (GBS). Antibodies against nerve gangliosides found in GBS patients recognize cross‐reactive epitopes in the lipopolysaccharide (LPS) of C. jejuni. This led to the molecular mimicry hypothesis of GBS. We immunized eleven rabbits with a LPS extracted from HS:19 C. jejuni strain isolated from a patient with GBS and complete Freund's adjuvant (CFA)(group I). In a second experiment we immunized seven rabbits with LPS, CFA and keyhole limpet hemocyanin (KLH)(group II). All group I rabbits developed high titers of anti‐LPS, anti‐GM1, anti‐GD1b antibodies and lower titers of anti‐GD1a. One rabbit, 50 days after initial inoculation, showed tremor and weakness. All rabbits of group II developed high titres of antiganglioside antibodies and six animals showed weakness 59–113 days after initial inoculation. Two rabbits died. Pathology showed mild to moderate, tendentially grouped, axonal degeneration in sciatic nerves of four out of five animals. Control rabbits of group I (immunized with CFA only) did not develop antibodies, controls of group II (immunized with CFA + KLH) developed low titers of IgG anti‐GM1. None developed neurological signs or showed axonal degeneration. C. jejuni LPS is a potent B‐cell stimulator capable to induce a strong antiganglioside response in rabbits. However, to induce the neuropathy is crucial to employ KLH, a glycoprotein known to stimulate both humoral and cellular responses. This animal model reproduces the pathogenetic process hypothesized in axonal GBS with antiganglioside antibodies post C. jejuni infection. 相似文献
24.
25.
This superb little book offers a wealth of information, practicaladvice and food for thought for all trainees in critical care.It will be useful for students and doctors preparing for theirfirst 相似文献
26.
27.
A prospective study of the management of menorrhagia in new patients presenting to gynaecological outpatients was undertaken at four centres in Northern Ireland and two in Great Britain. 325 patients were enrolled, the majority of whom (87%) had severe menorrhagia. Patients in all six centres were similar in relation to age, marital status, parity, use of contraception and severity of symptoms. 62% of the patients were managed medically, improved and were discharged. The rates of surgical intervention, in particular in women aged less than 40, appeared higher in the Northern Ireland hospitals than Great Britain. There is a need to review and audit current practices in the management of menorrhagia. 相似文献
28.
29.
30.
Xiaohua He Edith V Sullivan Roger K Stankovic Clive G Harper Adolf Pfefferbaum 《Neuropsychopharmacology》2007,32(10):2207-2216
The relative roles of alcohol and thiamine deficiency in causing brain damage remain controversial in alcoholics without the Wernicke-Korsakoff syndrome. Experimental control over alcohol consumption and diet are impossible in humans but can be accomplished in animal models. This experiment was designed to differentiate the separate and combined effects on the macro- and ultrastructure of the corpus callosum of thiamine deficiency and voluntary alcohol consumption. Adult male alcohol-preferring (P) rats (9 chronically alcohol-exposed and 9 water controls) received a thiamine-deficient diet for 2 weeks. There were four groups: five rats previously exposed to alcohol were treated with pyrithiamine (a thiamine phosphorylation inhibitor); five rats never exposed to alcohol were treated with pyrithiamine; four alcohol-exposed rats were treated with thiamine; and four rats never exposed to alcohol were treated with thiamine. On day 14, thiamine was restored in all 18 rats; 2 weeks later the 10 pyrithiamine-treated rats received intraperitoneal thiamine. The rats were perfused 61 days post-pyrithiamine treatment at age 598 days. Brains were dissected and weight and volumes were calculated. Sagittal sections were stained to measure white matter structures. The corpus callosum was examined using transmission electron microscopy to determine density of myelinated fibers, fiber diameter, and myelin thickness. The corpus callosum in the alcohol/pyrithiamine group was significantly thinner, had greater fiber density, higher percentage of small fibers, and myelin thinning than in the alcohol/thiamine and water/thiamine groups. Several measures showed a graded effect, where the alcohol/pyrithiamine group had greater pathology than the water/pyrithiamine group, which had greater pathology than the two thiamine-replete groups. Across all 16 rats, thinner myelin sheaths correlated with higher percentage of small fibers. Myelin thickness and axon diameter together accounted for 71% of the variance associated with percentage of small fibers. Significant abnormalities in the alcohol/pyrithiamine group and lack of abnormality in the alcohol-exposed/thiamine-replete group indicate that thiamine deficiency caused white matter damage. The graded abnormalities across the dually to singly treated animals support a compounding effect of alcohol exposure and thiamine depletion, and indicate the potential for interaction between alcohol and thiamine deficiency in human alcohol-related brain damage. 相似文献