全文获取类型
收费全文 | 917753篇 |
免费 | 63935篇 |
国内免费 | 2372篇 |
专业分类
耳鼻咽喉 | 12810篇 |
儿科学 | 29068篇 |
妇产科学 | 26483篇 |
基础医学 | 128817篇 |
口腔科学 | 25241篇 |
临床医学 | 76726篇 |
内科学 | 186683篇 |
皮肤病学 | 19224篇 |
神经病学 | 73403篇 |
特种医学 | 37139篇 |
外国民族医学 | 337篇 |
外科学 | 144719篇 |
综合类 | 19322篇 |
一般理论 | 257篇 |
预防医学 | 66171篇 |
眼科学 | 20406篇 |
药学 | 65196篇 |
1篇 | |
中国医学 | 1808篇 |
肿瘤学 | 50249篇 |
出版年
2018年 | 9396篇 |
2017年 | 7424篇 |
2016年 | 7944篇 |
2015年 | 9009篇 |
2014年 | 12810篇 |
2013年 | 19941篇 |
2012年 | 26612篇 |
2011年 | 28329篇 |
2010年 | 17165篇 |
2009年 | 16350篇 |
2008年 | 27186篇 |
2007年 | 28788篇 |
2006年 | 29034篇 |
2005年 | 28519篇 |
2004年 | 27323篇 |
2003年 | 26467篇 |
2002年 | 26051篇 |
2001年 | 41627篇 |
2000年 | 42785篇 |
1999年 | 36521篇 |
1998年 | 10231篇 |
1997年 | 9370篇 |
1996年 | 9294篇 |
1995年 | 8634篇 |
1994年 | 8246篇 |
1993年 | 7731篇 |
1992年 | 28394篇 |
1991年 | 27170篇 |
1990年 | 26572篇 |
1989年 | 25497篇 |
1988年 | 23726篇 |
1987年 | 23332篇 |
1986年 | 22413篇 |
1985年 | 21316篇 |
1984年 | 15991篇 |
1983年 | 13644篇 |
1982年 | 8284篇 |
1981年 | 7219篇 |
1979年 | 14705篇 |
1978年 | 10355篇 |
1977年 | 8759篇 |
1976年 | 8265篇 |
1975年 | 9037篇 |
1974年 | 10794篇 |
1973年 | 10269篇 |
1972年 | 9751篇 |
1971年 | 8988篇 |
1970年 | 8660篇 |
1969年 | 8086篇 |
1968年 | 7730篇 |
排序方式: 共有10000条查询结果,搜索用时 10 毫秒
971.
Report of the Canadian Hypertension Society Consensus Conference: 2. Nonpharmacologic management and prevention of hypertensive disorders in pregnancy 总被引:5,自引:3,他引:2 下载免费PDF全文
J M Moutquin P R Garner R F Burrows E Rey M E Helewa I R Lange S W Rabkin 《Canadian Medical Association journal》1997,157(7):907-919
OBJECTIVE: To provide Canadian physicians with comprehensive, evidence-based guidelines for the nonpharmacologic management and prevention of gestational hypertension and pre-existing hypertension during pregnancy. OPTIONS: Lifestyle modifications, dietary or nutrient interventions, plasma volume expansion and use of prostaglandin precursors or inhibitors. OUTCOMES: In gestational hypertension, prevention of complications and death related to either its occurrence (primary or secondary prevention) or its severity (tertiary prevention). In pre-existing hypertension, prevention of superimposed gestational hypertension and intrauterine growth retardation. EVIDENCE: Articles retrieved from the pregnancy and childbirth module of the Cochrane Database of Systematic Reviews; pertinent articles published from 1966 to 1996, retrieved through a MEDLINE search; and review of original randomized trials from 1942 to 1996. If evidence was unavailable, consensus was reached by the members of the consensus panel set up by the Canadian Hypertension Society. VALUES: High priority was given to prevention of adverse maternal and neonatal outcomes in pregnancies with established hypertension and in those at high risk of gestational hypertension through the provision of effective nonpharmacologic management. BENEFITS, HARMS AND COSTS: Reduction in rate of long-term hospital admissions among women with gestational hypertension, with establishment of safe home-care blood pressure monitoring and appropriate rest. Targeting prophylactic interventions in selected high-risk groups may avoid ineffective use in the general population. Cost was not considered. RECOMMENDATION: Nonpharmacologic management should be considered for pregnant women with a systolic blood pressure of 140-150 mm Hg or a diastolic pressure of 90-99 mm Hg, or both, measured in a clinical setting. A short-term hospital stay may be required for diagnosis and for ruling out severe gestational hypertension (preeclampsia). In the latter case, the only effective treatment is delivery. Palliative management, dependent on blood pressure, gestational age and presence of associated maternal and fetal risk factors, includes close supervision, limitation of activities and some bed rest. A normal diet without salt restriction is advised. Promising preventive interventions that may reduce the incidence of gestational hypertension, especially with proteinuria, include calcium supplementation (2 g/d), fish oil supplementation and low-dose acetylsalicylic acid therapy, particularly in women at high risk for early-onset gestational hypertension. Pre-existing hypertension should be managed the same way as before pregnancy. However, additional concerns are the effects on fetal well-being and the worsening of hypertension during the second half of pregnancy. There is, as yet, no treatment that will prevent exacerbation of the condition. VALIDATION: The guidelines share the principles in consensus reports from the US and Australia on the nonpharmacologic management of hypertension in pregnancy. 相似文献
972.
973.
American Diabetes Association The initial draft of this paper was prepared by Rebecca G. Schafer MS RD ; Betsy Bohannon MS RD; Marion J. Franz MS RD; Janine Freeman RD; Alberta Holmes MS RD; Sue McLaughlin RD; Linda B. Haas RN; Davida F. Kruger MSN RN; Rodney A. Lorenz MD; Molly M.McMahon MD 《Journal of the American Dietetic Association》1997,97(1):52-53
974.
975.
976.
Neurosarcoma is a rare tumour originating from the sheath of peripheral nerves. Facial lesions have been reported in about
20 patients. We describe the MRI appearances of neurosarcoma with histological correlation in three patients. The lesions
lay in the submandibular region, the left parapharyngeal space and the right orbit. MRI showed a well-defined mass with mixed
components. The lesions were moderately heterogeneous on T1-weighted images in two cases and on T2-weighted images in all
cases. Gadolinium enhancement occurred in all cases to variable degrees. In two cases, small high signal foci were seen on
T2-weighted sequences. MRI appearances of neurosarcoma are not specific.
Received: 3 September 1996 Accepted: 26 November 1996 相似文献
977.
J. G. Boonstra Johan W. van der Pijl Yves F. C. Smets Herman H. P. J. Lemkes Jan Ringers Leendert A. van Es F. J. van der Woude Jan A. Bruijn 《Transplant international》1997,10(6):451-456
To examine the incidence of interstitial and vascular
rejection in pancreas allografts and its impact on graft survival, we studied 36 percutaneous pancreas biopsies and 10 pancreas
transplantectomy specimens from 32 patients who had undergone simultaneous pancreas-kidney transplantation. Interstitial rejection
(IR) was predominantly found in the biopsies, while vascular rejection (VR) was most prominent in the transplantectomies.
Pancreas graft survival was significantly decreased for pancreas grafts that had suffered from vascular rejection when compared
to those with only interstitial rejection. Potential rejection markers, i. e., serum amylase, glucose, creatinine, and urinary
amylase, did not correlate with histological signs of rejection, although increased levels of serum amylase were, in all but
one case, associated with rejection.We conclude that a percutaneous pancreas biopsy remains the most reliable method to determine
pancreas rejection, and that by distinguishing between IR andVR, a pancreas biopsy may provide important diagnostic as well
as prognostic information.
Received: 6 March 1997 Received after revision: 5 June 1997 Accepted: 30 June 1997 相似文献
978.
Abstract One hundred eighty-one consecutive patients with fulminant hepatic failure (FHF) presenting in a 2-year period were reviewed. In this cohort we examined the impact of pretransplant renal failure on mortality and morbidity following orthotopic liver transplantation (OLTx). Twenty-seven patients (18 female, 9 male) with a median age of 43.5 years (range 19–65 years) underwent OLTx. FHF was due to idiosyncratic drug reaction ( n = 4), paracetamol overdose ( n = 3), seronegative hepatitis ( n = 17), hepatitis B ( n = 1), veno-occlusive disease ( n = 1), and Wilson's disease ( n = 1). Renal failure was present in 14 patients, 7 of whom died (whereas there was 100 % survival in patients without renal failure). Pretransplant renal failure was associated with prolonged mechanical ventilation (13 days vs 6 days, P = 0.05), prolonged intensive care stay (17 days vs 8 days, P - 0.01) and prolonged hospital stay (27 vs 21 days, P = NS). Pretransplant renal failure did not predict renal dysfunction at 1 year after OLTx. We conclude that the survival of patients transplanted for FHF is inferior to that of patients transplanted for chronic liver disease (67 % vs 88 % 1-year survival in Birmingham). For patients with FHF undergoing transplantation, pretransplant renal failure strongly predicts poor outcome with significantly greater consumption of resources. 相似文献
979.
980.
Preventive care for patients following myocardial infarction. The Wessex Research Network (WReN) 总被引:2,自引:1,他引:1
OBJECTIVE: We aimed to assess general practice care for patients following
a myocardial infarction (MI). METHOD: A structured review was carried out
of general practice records of patients identified from hospital
administration data. A total of 266 survivors following MI were identified
from the discharge data of 13 hospitals in Southern England and registered
with 71 GPs belonging to the Wessex Research Network. Median time since
hospital discharge was 2.1 years. The main outcome measures were the
provision of appropriate preventive care, including cardiac rehabilitation,
drug therapy, and lifestyle advice for modifiable risk factors. RESULTS:
Basic care was provided to nearly all patients; 253 (95.1%, 95% Cl
91.8-97.4) had blood pressure documented after their MI, 216 of 234
patients eligible for aspirin (92.3%; 88.1-95.4) had been recommended
treatment, and the provision of advice on smoking cessation was documented
for 27 of 33 continuing smokers (81.8%; 64.5-93.0). However, only 73 of 236
patients eligible to attend a structured rehabilitation programme (30.9%;
25.0-36.8) were documented as having received rehabilitation. Of 89
patients with heart failure following MI, 33 (37.1%; 27.1-48.0) had no
record of having been offered treatment with an ACE inhibitor. Total
cholesterol measurement was documented for only 144 patients (54.1%;
48.1-60.1). We estimate that there is still the potential to prevent
between 4 and 9 deaths in this group of 266 surviving patients in the next
2 years by further improving the quality of follow-up care. CONCLUSIONS:
Preventive care in patients with proven ischaemic heart disease in general
practice remains haphazard, even among doctors enthusiastic to participate
in research and to audit their quality of care. As general practitioners we
should ensure that we are providing high quality preventive care to
patients with clinical disease before we focus on the even more demanding
task of primary prevention.
相似文献