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排序方式: 共有1233条查询结果,搜索用时 15 毫秒
1.
Alpha2-HS glycoprotein phenotypes and quantitative hormone and bone measures in postmenopausal women
June E. Eichner Christopher A. Friedrich Jane A. Cauley Mohammad I. Kamboh James P. Gutai Lewis H. Kuller Robert E. Ferrell 《Calcified tissue international》1990,47(6):345-349
Summary It has been suggested that inherited traits play a role in the development of osteoporosis by providing a background for the
modulation of gene expression. In this study, we examine the influence of the different alleles of alpha2-HS glycoprotein (AHSG), a protein of the bone matrix, on quantitative estrogens, estrone and estradiol, and bone measures,
bone area and density. Estrogens provide a protective effect against fractures in older women and were thus included in the
analyses. Isoelectric focusing of AHSG from sera followed by immunoblotting was used to type 163 white post-menopausal women
participating in a clinical trial of the effects of walking on bone loss. Plasma hormones were measured by a combination of
extraction, column chromatography, and radioimmunoassay; bone measures on the dominant radius were determined with computerized
tomography. Analysis of variance was done on estrogen and bone measures after controlling for the effects of age and body
mass index. The two major alleles of AHSG result in three phenotypes, designated AHSG 1-1, AHSG 2-1, and AHSG 2-2. The AHSG
1-1 homozygote showed a decreased concentration of estradiol, the AHSG 2-2 homozygote showed an increased concentration, and
the AHSG 2-1 heterozygote was intermediate (P=0.001). Estrone demonstrated a similar pattern in residual analysis although it did not reach statistical significance. 相似文献
2.
Preliminary evidence for a role of apolipoprotein E alleles in identifying haemodialysis patients at high vascular risk 总被引:1,自引:0,他引:1
Olmer M; Renucci JE; Planells R; Bouchouareb D; Purgus R 《Nephrology, dialysis, transplantation》1997,12(4):691-693
Conventional risk factors have very low predictive power in identifying
haemodialysis patients at high risk of vascular accidents. A role for
apolipoprotein E isotypes was looked for in a small, but rigorously
defined, cohort of longterm haemodialysis patients. In individuals with
high vascular risk, as identified by higher common carotid intima/media
thickness, we found an excess of apolipoprotein E4 alleles. This
preliminary result requires confirmation in large patient cohorts.
相似文献
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Hodgkin disease: CT of the thymus 总被引:2,自引:0,他引:2
The computed tomography (CT) scans in two groups of patients with Hodgkin disease were reviewed to determine the frequency of thymic enlargement. In 50 CT scans from 50 patients with evidence of thoracic disease on CT scans who were examined for primary staging, the thymus was enlarged in 15 of 50 (30%). Fifty CT scans were obtained from 44 patients at the time of 50 separate episodes of known or suspected relapse. Relapse occurred in the mediastinum in 12 episodes, lung parenchyma in five, and both sites in one. Thymic enlargement thought to be due to involvement by disease was present in seven of 18 (38%). Mediastinal disease was associated with thymic enlargement in all but one patient in whom a thymic cyst developed after radiation therapy. Differentiation of thymic enlargement from enlarged superior mediastinal lymph nodes was easily made in all but two patients. Thymic enlargement in the absence of lymph node enlargement may indicate a different disease, since isolated Hodgkin disease of the thymus is uncommon. Primary thymic tumor should be considered initially, whereas after treatment, rebound hyperplasia of the thymus may be the cause of enlargement. 相似文献
6.
Solitary bronchioloalveolar carcinoma: CT criteria 总被引:14,自引:0,他引:14
Kuhlman JE; Fishman EK; Kuhajda FP; Meziane MM; Khouri NF; Zerhouni EA; Siegelman SS 《Radiology》1988,167(2):379-382
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis. 相似文献
7.
A randomized controlled trial of electromagnetic therapy in the primary care management of venous leg ulceration 总被引:1,自引:1,他引:0
OBJECTIVE: The aim was to establish the potential efficacy, tolerabilityand side-effect profile of electromagnetic therapy as an adjunctto conventional dressings in the treatment of venous leg ulcers. METHOD: A prospective, randomized, double blind controlled clinicaltrial was carried out in a dedicated leg ulcer clinic basedin one urban general practice. Nineteen patients with leg ulcersof confirmed venous aetiology were assessed. The main outcomemeasures were rate and scale of venous leg ulcer healing, changesin patient-reported pain levels, quality of life, degree ofmobility, side effect profile and acceptability to patientsand staff. RESULTS: Sixty-eight per cent of patients attending this dedicated clinicachieved improvements in the size of their ulcer (4, 21%, healedfully) and in reduced pain levels (P < 0.05) during the trial,despite the chronicity of ulcer histories. Patients treatedwith electromagnetic therapy at 800 Hz were found at day 50to have significantly greater healing (P < 0.05) and paincontrol (P < 0.05) than placebo therapy or treatment with600 Hz. All patients reported improved mobility at the end ofthe study. The electromagnetic therapy was well tolerated bypatients, with no differences between groups in reporting adverseevents, and proved acceptable to staff. CONCLUSION: Despite the small numbers in this pilot study, electromagnetictherapy provided significant gains in the healing of venousleg ulcers and reduction in pain. Keywords. Electromagnetic therapy, RCT, leg ulcers, primary care. 相似文献
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Hormonal fluctuations associated with the menstrual cycle influence
appetite control and eating behaviour. Energy intake varies during the
reproductive cycle in humans and animals, with a periovulatory nadir and a
luteal phase peak. Patterns of macronutrient selection show less
consistency but a number of studies report carbohydrate cravings in the
premenstrual phase, particularly in women with premenstrual syndrome. The
cyclical nature of food cravings are frequently, but not invariably,
associated with depression. Fluctuations in appetite, cravings and energy
intake during the menstrual cycle may occur in parallel with cyclical
rhythms in serotonin, which can be accompanied by affective symptoms. The
premenstrual phase can be considered as a time when women are especially
vulnerable to overconsumption, food craving and depression; this is often
associated with low serotonin activity.
相似文献