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排序方式: 共有1078条查询结果,搜索用时 15 毫秒
71.
Sharon A Greenberg Ilan Youngster Nathaniel A Cohen Dan M Livovsky Jacob Strahilevitz Eran Israeli Ehud Melzer Kalman Paz Naomi Fliss-Isakov Nitsan Maharshak 《World journal of gastroenterology : WJG》2018,24(47):5403-5414
AIM To evaluate and describe the efficacy of fecal microbiota transplantation(FMT) for Clostridium difficile infection(CDI) in a national Israeli cohort.METHODS All patients who received FMT for recurrent(recurrence within 8 wk of the previous treatment) or refractory CDI from 2013 through 2017 in all the five medical centers in Israel currently performing FMT were included. Stool donors were screened according to the Israeli Ministry of Health guidelines. Clinical and laboratory data of patients were collected from patients' medical files, and they included indications for FMT, risk factors for CDI and disease severity. Primary outcome was FMT success(at least 2 mo free of CDI-related diarrhea post-FMT). Secondary outcomes included initial response to FMT(cessation of diarrhea within 7 d) and recurrence at 6 mo.RESULTS There were 111 FMTs for CDI, with a median age of 70 years [interquartile range(IQR): 53-82], and 42%(47) males. Fifty patients(45%) were treated via the lower gastrointestinal(LGI, represented only by colonoscopy) route, 37(33%) via capsules, and 24(22%) via the upper gastrointestinal(UGI) route. The overall success rate was 87.4%(97 patients), with no significant difference between routes of administration(P = 0.338). In the univariant analysis, FMT success correlated with milder disease(P = 0.01), ambulatory setting(P 0.05) and lower Charlson comorbidity score(P 0.05). In the multivariant analysis, only severe CDI [odd ratio(OR) = 0.14, P 0.05] and inpatient FMT(OR = 0.19, P 0.05) were each independently inversely related to FMT success. There were 35(32%) patients younger than 60 years of age, and 14(40%) of them had a background of inflammatory bowel disease.CONCLUSION FMT is a safe and effective treatment for CDI, with capsules emerging as a successful and well-tolerated route. Severe CDI is less likely to respond to FMT. 相似文献
72.
Cognitive function is a key aspect of healthy aging. Inflammation associated with normal aging, also called inflammaging is a primary risk factor for cognitive decline. A diet high in fruits and vegetable and lower in calories, particularly a Mediterranean Diet, may lower the risk of age-related cognitive decline due in part to the associated high intake of antioxidants and polyphenols. A phenolic, Palm Fruit Bioactive complex (PFBc) derived from the extraction process of palm oil from oil palm fruit (Elaeis guineensis), is reported to offset inflammation due to its high antioxidant, especially vitamin E, and polyphenol content. The benefit is thought to be achieved via the influence of antioxidants on gene expression. It is the purpose of this comprehensive review to discuss the etiology, including gene expression, of mild cognitive impairment (MCI) specific to dietary intake of antioxidants and polyphenols and to focus on the potential impact of nutritional interventions specifically PFBc has on MCI. Several in vitro, in vivo and animal studies support multiple benefits of PFBc especially for improving cognitive function via anti-inflammatory and antioxidant mechanisms. While more human studies are needed, those completed thus far support the benefit of consuming PFBc to enhance cognitive function via its anti-inflammatory antioxidant functions. 相似文献
73.
This work (in three parts) inquires into whether respirable dusts derived from the machining of six composite-epoxy materials (e.g., aircraft industry) may pose a health risk to the operators. Dust samples representative of a variety of composites and structural components were aerodynamically sized and fractionated. Bulk and fractionated samples were examined by light and electron microscopy and analyzed chemically by thermogravimetry (TGA), gas chromatography (GC) and mass spectrometry (MS). Relative fractions of respirable to total mass of bulk samples were less than 3%; aerodynamic diameters of fractionated particles ranged from 0.8 to 2.0 microns. By microscopy, bulk particles ranged from 7 to 11 microns in diameter, with mean aspect ratios from 4 to 8:1. Mean diameter of fractionated particles was 2.7 microns. By TGA, weight losses were negligible below 250 degrees C and variable but elevated at temperatures up to 860 degrees C. In assays of vapors released at 250 degrees C, GC/MS indicated a variety of compounds in different amounts for each sample. We conclude that under the present machining protocols, dusts at the tool face contained few particles of respirable size with no evidence of splitting of fibers longitudinally and were of a low volatilizable chemical content. Overall, composites were judged to be well cured and thermally stable. 相似文献
74.
Methylation study of a population environmentally exposed to arsenic in drinking water. 总被引:8,自引:3,他引:8 下载免费PDF全文
C Hopenhayn-Rich M L Biggs A H Smith D A Kalman L E Moore 《Environmental health perspectives》1996,104(6):620-628
Methylation is considered the detoxification pathway for inorganic arsenic (InAs), an established human carcinogen. Urinary speciation analysis is used to assess the distribution of metabolites [monomethylarsonate (MMA), dimethylarsinate (DMA), and unmethylated arsenic (InAs)], as indicators of methylation capacity. We conducted a large biomarker study in northern Chile of a population chronically exposed to high levels of arsenic in drinking water. We report the results of the methylation study, which focused on the effects of exposure and other variables on the percent InAs, MMA, DMA, and the ratio of MMA to DMA in urine. The study consisted of 122 people in a town with arsenic water levels around 600 micrograms/l and 98 participants in a neighboring town with arsenic levels in water of about 15 micrograms/l. The corresponding mean urinary arsenic levels were 580 micrograms/l and 60 micrograms/l, of which 18.4% and 14.9% were InAs, respectively. The main differences were found for MMA:DMA; exposure, smoking, and being male were associated with higher MMA:DMA, while longer residence, Atacameño ethnicity, and being female were associated with lower MMA:DMA. Together, these variables explained about 30% of the variability in MMA:DMA. Overall, there was no evidence of a threshold for methylation capacity, even at very high exposures, and the interindividual differences were within a much wider range than those attributed to the variables investigated. The differences in percent InAs were small and within the ranges of other studies of background exposure levels. The biological significance of MMA:DMA, which was more than 1.5 times greater in the exposed group, and its relationship to sex, length of exposure, and ethnicity need further investigation because its relevance to health risk is not clear. 相似文献
75.
Crispin H. Pierce Russell L. Dills Michael S. Morgan Paolo Vicini David A. Kalman 《International archives of occupational and environmental health》1998,71(7):433-444
Objectives: Widespread exposure to toluene occurs in the printing, painting, automotive, shoemaking, and speaker-manufacturing industries.
The relationship between air concentrations and the absorbed dose is confounded by dermal exposure, personal protective devices,
movement throughout the workplace, and interindividual differences in toluene uptake and elimination. Methods: To determine the best biological indicator of exposure we examined the blood and alveolar breath concentrations of toluene
as well as the urinary excretion rates of hippuric acid and of o-, m-, and p-cresols from 33 controlled human inhalation exposures to 50 ppm for 2 h. Results: Among the metabolites, o-cresol was least influenced by background contributions, whereas the p-cresol and hippuric acid rates were obscured by endogenous and dietary sources. Toluene levels in alveolar breath proved
to be the most accurate and noninvasive indicator of the absorbed dose. A physiologic model described blood and breath data
using four measured anthropometric parameters and the fit values of extrahepatic metabolism and adipose-tissue blood flow.
Conclusions: After breathing rate and extrahepatic metabolism had been set to conservative (protective) values (the 97.5th and 2.5th percentiles,
respectively) the model predicted that pre-final-shift breath levels of ≤10 μmol/m3 and post-final-shift levels of ≤150 μmol/m3 corresponded to average workplace exposure levels of ≤50 ppm toluene. Alternately, we used the distributions and covariances
of the measured and fit model parameters to yield conservative pre-final-shift levels of ≤7.3 μmol/m3 and post-final-shift breath levels of ≤120 μmol/m3 that were reflective of workplace exposure levels of ≤50 ppm toluene.
Received: 30 December 1997 / Accepted: 12 June 1998 相似文献
76.
Pesticide exposure of children in an agricultural community: evidence of household proximity to farmland and take home exposure pathways 总被引:10,自引:0,他引:10
Children's exposure to organophosphorus (OP) pesticides in an agricultural community in central Washington State was determined. Spot urine and hand wipe samples were collected from 109 children 9 months to 6 years of age, as were house dust samples, and wipe samples from various surfaces. Children were categorized based on parental occupation (agricultural vs nonagricultural) and on household proximity to pesticide-treated orchards. Median house dust concentrations of dimethyl OP pesticides in homes of agricultural families were seven times higher than those of reference families (1. 92 vs 0.27 microg/g; P<0.001). Median pesticide metabolite concentrations in agricultural children were five times higher than those in reference children (0.05 vs 0.01 microg/ml; P=0.09). Median pesticide concentrations in housedust (P=0.01) and metabolite concentrations in urine (P=0.01) from agricultural families were significantly higher in the children living near treated orchards (within 200 ft or 60 m) than those living more distant. Ten of 61 agricultural children had detectable OP pesticide levles on their hands, whereas none of the reference children had detectable levels. These findings indicate that children living with parents who work with agricultural pesticides, or who live in proximity to pesticide-treated farmland, have higher exposures than do other children living in the same community Copyright 2000 Academic Press. 相似文献
77.
Liu LJ Box M Kalman D Kaufman J Koenig J Larson T Lumley T Sheppard L Wallace L 《Environmental health perspectives》2003,111(7):909-918
In this article we present results from a 2-year comprehensive exposure assessment study that examined the particulate matter (PM) exposures and health effects in 108 individuals with and without chronic obstructive pulmonary disease (COPD), coronary heart disease (CHD), and asthma. The average personal exposures to PM with aerodynamic diameters < 2.5 microm (PM2.5) were similar to the average outdoor PM2.5 concentrations but significantly higher than the average indoor concentrations. Personal PM2.5 exposures in our study groups were lower than those reported in other panel studies of susceptible populations. Indoor and outdoor PM2.5, PM10 (PM with aerodynamic diameters < 10 microm), and the ratio of PM2.5 to PM10 were significantly higher during the heating season. The increase in outdoor PM10 in winter was primarily due to an increase in the PM2.5 fraction. A similar seasonal variation was found for personal PM2.5. The high-risk subjects in our study engaged in an equal amount of dust-generating activities compared with the healthy elderly subjects. The children in the study experienced the highest indoor PM2.5 and PM10 concentrations. Personal PM2.5 exposures varied by study group, with elderly healthy and CHD subjects having the lowest exposures and asthmatic children having the highest exposures. Within study groups, the PM2.5 exposure varied depending on residence because of different particle infiltration efficiencies. Although we found a wide range of longitudinal correlations between central-site and personal PM2.5 measurements, the longitudinal r is closely related to the particle infiltration efficiency. PM2.5 exposures among the COPD and CHD subjects can be predicted with relatively good power with a microenvironmental model composed of three microenvironments. The prediction power is the lowest for the asthmatic children. 相似文献
78.
Arsenic in drinking water and skin lesions: dose-response data from West Bengal,India 总被引:3,自引:0,他引:3
Haque R Mazumder DN Samanta S Ghosh N Kalman D Smith MM Mitra S Santra A Lahiri S Das S De BK Smith AH 《Epidemiology (Cambridge, Mass.)》2003,14(2):174-182
BACKGROUND: Over 6 million people live in areas of West Bengal, India, where groundwater sources are contaminated with naturally occurring arsenic. The key objective of this nested case-control study was to characterize the dose-response relation between low arsenic concentrations in drinking water and arsenic-induced skin keratoses and hyperpigmentation. METHODS: We selected cases (persons with arsenic-induced skin lesions) and age- and sex-matched controls from participants in a 1995-1996 cross-sectional survey in West Bengal. We used a detailed assessment of arsenic exposure that covered at least 20 years. Participants were reexamined between 1998 and 2000. Consensus agreement by four physicians reviewing the skin lesion photographs confirmed the diagnosis in 87% of cases clinically diagnosed in the field. RESULTS: The average peak arsenic concentration in drinking water was 325 microg/liter for cases and 180 microg/liter for controls. The average latency for skin lesions was 23 years from first exposure. We found strong dose-response gradients with both peak and average arsenic water concentrations. CONCLUSIONS: The lowest peak arsenic ingested by a confirmed case was 115 microg/liter. Confirmation of case diagnosis and intensive longitudinal exposure assessment provide the basis for a detailed dose-response evaluation of arsenic-caused skin lesions. 相似文献
79.
Four adolescent girls were referred for psychiatric assessment because of suspected anorexia nervosa. Although all of them had lost at least 15% of their body weight, investigation showed that they did not meet the criteria for anorexia nervosa. In all cases, refusal to eat resulted from fear of vomiting following a viral illness and not from a desire to lose weight. Their family configurations and personal histories showed many similarities, including constricted range of affect and a notable lack of anger. With counseling and, in one case, psychotropic medication, the patients recovered promptly. 相似文献
80.
We reviewed our experience with femorofemoral bypass during the past 10 years to define its role relative to other methods in the treatment of aortoiliac occlusive disease. The cumulative patency rate for 82 patients was 80% +/- 5% at 1 year and 67% +/- 7% at 2 and 3 years. The operation was most likely to be successful if the indication was claudication (p less than 0.05) and if the operation was performed as the primary procedure (p less than 0.01). There was no significant difference when patients with or without profundaplasty were compared. It is concluded that femorofemoral bypass is indicated to treat symptomatic unilateral iliac disease when transluminal dilatation is not possible. Femorofemoral bypass is also the procedure of choice for aortofemoral graft occlusion when the thrombosed limb cannot be reopened. Femorofemoral bypass is recommended for both high- and low-risk patients when indicated. 相似文献