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排序方式: 共有209条查询结果,搜索用时 15 毫秒
1.
Resting metabolic rate and the influence of the pretesting environment.   总被引:1,自引:0,他引:1  
We examined the effect of pretesting environment on measurement of resting metabolic rate (RMR). RMR was measured in 18 older (66.1 +/- 1.4 y) individuals after an overnight stay in the Clinical Research Center (ie, inpatient) and after subjects transported themselves to the laboratory (ie, outpatient). Similar measurements were also performed after an 8-wk endurance-training program. RMR was higher (P less than 0.01) before exercise training in subjects who transported themselves to the laboratory (ie, outpatients; 4.9 +/- 0.13 kJ/min) than in inpatients (4.6 +/- 0.13 kJ/min) and after exercise training in outpatients (5.4 +/- 0.08 kJ/min) vs inpatients (5.0 +/- 0.13 kJ/min). Training increased RMR under both inpatient (10%; P less than 0.01) and outpatient (11%; P less than 0.01) conditions. We conclude that RMR is higher when measured under outpatient conditions in older volunteers. Therefore, when daily energy requirements based on the assessment of RMR are being estimated, the pretesting environment should be considered. However, the exercise-training-induced increase in RMR can be detected by using either an inpatient or an outpatient protocol.  相似文献   
2.
个体化下肢小腿假肢接受腔设计的生物力学评价技术研究   总被引:3,自引:0,他引:3  
作为传递体重、固定假肢的部件 ,接受腔对于小腿假肢使用的舒适性和方便程度有决定性的作用。本研究建立了基于有限元应力分析的小腿假肢生物力学评价技术平台 ,实现了小腿残端 /接受腔 3D几何建模与信息交互、三维有限元自动建模及应力分析。 3D模型与信息交互的实现基于得到广泛支持的OpenGL技术 ,有限元模型的构建采用了专门针对小腿残端 /接受腔结构特点的自动建模方法 ,通过构建档案数据库系统作为整个系统的操作平台。该技术平台可与现有的CAD/CAM系统相结合 ,为接受腔的个体化设计提供生物力学定量化依据。其临床应用将改善传统的设计流程 ,提高设计效率。同时 ,它也是未来构建接受腔设计专家 /智能系统的基础。  相似文献   
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4.
Lung carcinoma remains one of the most frequent and aggressive human neoplasms. Fortunately, in the last decades, the increasing knowledge of the molecular mechanisms leading to cancer development has allowed the use of targeted therapies with improvement of prognosis in many patients. Clinical management has also changed after the introduction of endobronchialultrasonographic bronchoscopy that allows a conservative staging of lung tumors, avoiding the need of mediastinoscopy for lymph node staging. Lung pathologists and cytopathologists are facing the challenge of giving the more comprehensive prognostic and predictive information with ever smaller tissue or cytological samples. The aim of this review is to summarize the molecular testing for non-small cell lung carcinoma and how pathologists can contribute to the patient's outcome with a conscious management of biological samples.  相似文献   
5.
碱离子水饮用后血小板聚集率的的变化(附30例报告)   总被引:1,自引:0,他引:1  
目的:报告30例饮用豪斯牌碱离子水前、后血小板聚集率的变化。方法:饮用碱离子水前、后(2~3月,>3~6月)作比浊法血小板聚集试验,以1分钟、5分钟及5分钟内最大聚集率(Max%)为指标,同时检测部分血粘度指标及凝血因子,并用自动生化仪检测血糖、血脂、主要电解质及部分肝、肾功能。结果:饮碱离子水后,血小板聚集率明显下降,而以疾病组(Max>80%)下降尤为明显,P均<0.001。饮碱离子水后血小板聚集率的下降,部分可能与损伤的血管内皮得到修复有关。主要电解质及部分肝、肾功能无明显异常改变。结论:由于心、脑血管血栓性疾病患者血小板聚集率多明显升高,饮碱离子水后血小板聚集率明显下降,且长期饮用对主要电解质及部分肝、肾功能无明显异常改变,作者认为碱离子水使用方例、安全、有效、价廉,因而对心、脑血管血栓性疾病防治方面可能是一种积极的辅助方法,值得临床进一步探索。  相似文献   
6.
Endocrine changes resulting from the menopause transition dramatically modify women's hormonal milieu. The consequences of these changes not only lead to cessation of reproduction and accompanying symptoms in women, but also dramatically impact long-term health. Loss of estrogen has been associated with the development of cardiovascular disease. Central distribution and accumulation of adipose tissue, and the concomitant insulin resistant dyslipidemic state have emerged as important components of a cluster of metabolic abnormalities that are strongly related to coronary heart disease. Thus, estrogen deficiency may affect cardiovascular disease risk by mediating changes in body fat distribution. This article is an update of the literature in the area of menopause, hormone replacement therapy, and body fat distribution. Cross-sectional studies using anthropometric measurements of abdominal fat distribution most often failed to detect an effect of the menopause transition that was independent of advancing age and degree of obesity. The use of radiologic techniques such as DEXA and computed tomography, however, led to the conclusion that the menopause transition accelerates the selective deposition of intra-abdominal fat. Available longitudinal data also support an increase in central body fatness occurring with menopause. Most intervention trials on hormone replacement therapy and body fat distribution showed that the treatment prevented the increase in central adiposity that was noted in postmenopausal women receiving no treatment or placebo. These results are supported by retrospective studies that showed a lower WHR in hormone users vs non-users. Mechanisms potentially explaining the menopause-related acceleration in abdominal fat accumulation include changes in regional adipose tissue metabolism in the face of a positive energy imbalance. As some inconsistencies were found among studies, further investigations using longitudinal and intervention designs, as well as more precise methodologies to measure body fat distribution, are needed to clearly establish the effects of menopause and hormone replacement on abdominal body fat distribution and the concomitant increase in cardiovascular disease risk.  相似文献   
7.
Obesity is thought to be a heterogeneous disorder with several possible etiologies; therefore, by examining subtypes of obesity we attempt to understand obesity's heterogeneous nature. The purpose of this review was to investigate the roles of metabolic, body composition, and cardiovascular disease risk in subtypes of obesity. We briefly consider two subtypes of obesity that have been identified in the literature. One subset of individuals, termed the metabolically healthy, but obese (MHO), despite having large amounts of fat mass compared with at risk obese individuals shows a normal metabolic profile, but remarkably normal to high levels of insulin sensitivity. Preliminary evidence suggests that this could be due at least in part to lower visceral fat levels and earlier onset of obesity. A second subset, termed the metabolically obese, but normal weight (MONW), present with normal body mass index, but have significant risk factors for diabetes, metabolic syndrome, and cardiovascular disease, which could be due to higher fat mass and plasma triglycerides as well as higher visceral fat and liver content. We also briefly consider the potential role of adipose and gastrointestinal hormonal profiles in MHO and MONW individuals, which could lead to a better understanding of potential factors that may regulate their body composition. This information will eventually be invaluable in helping us understand factors that predispose to or protect obese individuals from metabolic and cardiovascular disease. Collectively, a greater understanding of the MHO and MONW individual has important implications for therapeutic decision making, the characterization of subjects in research protocols, and medical education.  相似文献   
8.
The daily energy requirements of older adults are unclear. Aging results in a decline in daily energy expenditure and intake, which are associated with greater gains in body fatness and a subsequently higher risk of morbidity and mortality. Understanding the energy requirements of older populations, therefore, has important clinical implications. Current world-wide recommendations suggest that energy needs of individuals above 50 y are of 1.51 times resting energy expenditure. Limited data suggest that this may be an underestimation of energy needs in older Caucasian women and men. In contrast, current energy requirement recommendations may be appropriate for older African-American women, because of their low rate of daily energy expenditure for their metabolic size. Aging is also associated with Alzheimer's and Parkinson's and recent data suggest that individuals with these chronic diseases actually have energy requirements that are at or below current recommendations. Physical activity is the most modifiable and variable component of daily energy expenditure and, therefore, energy requirements. Current data suggest that an inexpensive and simple measurement of physical activity is difficult in older adults, which limits our ability to accurately determine energy needs. Overall, current data suggest that energy needs of older adults may be higher than current world-wide recommendations, although future prospective data are needed in healthy, ethnic, and diseased populations. Accurate, unobtrusive, and inexpensive methods to measure physical activity are also needed to assess energy requirements.  相似文献   
9.
BACKGROUND: Lower resting energy expenditure (REE) in African American women may contribute to their obesity. The identification of uncoupling protein (UCP) genes has fueled a search for genes involved in energy metabolism in humans. OBJECTIVE: We examined variation in REE in relation to variation in UCP1, UCP2, and UCP3 in 141 women aged 18-21 y. DESIGN: Standard methods were used for REE measurements and genetic analysis. Body composition was determined with the use of dual-energy X-ray absorptiometry. Multivariate analysis was used to examine the effect of genotypes on REE and on fat mass in relation to other potentially confounding variables. RESULTS: REE was 295 kJ/d lower in African American women than in white women. No significant variation in REE was seen for UCP1, UCP2, and UCP3 (p-55; exon 3a; and exon 3b) variants after adjustment for other variables including smoking status. For the UCP3 exon 5 variant, REE was significantly (P = 0.019) lower in African American women with the CC genotype than in those with the TT genotype. In African American women, there was a significant trend (P = 0.012) toward lower REE and a weak but nonsignificant trend (P = 0.1) toward greater fat mass across the 3 genotypes (TT, CT, and CC). CONCLUSIONS: The significant and dose-dependent relation between lower REE and the C allele suggests that it may be a thrifty allele. The presence of this parsimonious energy metabolism in African American women, possibly linked to UCP3, may be implicated in their susceptibility to obesity. The absence of a UCP3 effect in white women is intriguing and needs to be explored to further understand possible interactions between UCP3 and other genes.  相似文献   
10.
Several adrenoceptor subtypes are expressed in adipocytes, which together exert their influence on adipocyte metabolism. Therefore, we specifically examined the interactive effect of Trp64Arg (beta3) and Glu12/Glu9 (alpha2b) adrenoceptor (AR) polymorphisms on energy metabolism and body composition in healthy women with a wide range of body habitus. We genotyped 909 unrelated women (age 55 +/- 12 [mean +/- SD] years, range 19-87; body weight 88 +/- 22 kg, range 40-167; and BMI 33 +/- 8 kg/m2, range 16-64) for Trp64Arg beta3AR and Glu12/Glu9 alpha2bAR variants. We examined the independent effect of the Glu12/Glu9 alpha2bAR variant on body composition and energy balance, in a large cohort of Caucasian women (n = 909). A second goal was to examine the interaction effect of Glu12/Glu9 alpha2bAR and Trp64Arg beta3AR on the same phenotypes. The obesity-related phenotypes studied were as follows: body weight, BMI, fat mass, visceral fat, fat-free mass, resting metabolic rate (RMR), VO2max, leisure time physical activity, and daily energy intake. Body composition and body fat distribution were measured by dual-energy X-ray absorptiometry and radiographic imagery, VO2max by a treadmill test to exhaustion, and RMR by indirect calorimetry. An analysis of covariance indicated that in the entire cohort, there was no significant difference between Glu12/Glu9 alpha2bAR carriers and control subjects for any of the obesity-related phenotypes that were examined. However, we observed a significant interaction effect of the Trp64Arg and Glu12/Glu9 variants on fat mass (P = 0.009) and percent fat (P = 0.016). Age, height, body weight, BMI, fat-free mass, visceral fat, energy expenditure, respiratory quotient, physical fitness, and energy intake were not different among groups. Collectively, these findings support an interaction effect of the two adrenoceptor variants on body fatness in Caucasian women, although the physiological mechanism by which they exert this effect remains to be determined.  相似文献   
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