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91.
Sarcopenia is a common and prominent geriatric syndrome, of major interest for daily clinical practice of professionals working with older people. The number of affected individuals and its relation with disability, frailty, many chronic diseases, lifestyle and adverse outcomes are extremely relevant for geriatric care. Moreover, biological changes that lead to the loss of muscle mass and strength are intrinsically related to the mechanisms of aging. It is not therefore surprising that research in this field is growing exponentially in recent years, and sarcopenia has been placed in recent years in the forefront of research in geriatric medicine and gerontology. The Spanish Society of Geriatrics and Gerontology has recently created an Observatory of Sarcopenia, which aims to promote educational and research activities in this field. The first activity of the Observatory has been to offer the Spanish speaking scientific community a review of the current status of sarcopenia, that may allow unifying concepts and fostering interest in this promising field of geriatrics.  相似文献   
92.
Sarcopenia is a common and prominent geriatric syndrome, of major interest for daily clinical practice of professionals working with older people. The number of affected individuals and its relation with disability, frailty, many chronic diseases, lifestyle and adverse outcomes are extremely relevant for geriatric care. Moreover, biological changes that lead to the loss of muscle mass and strength are intrinsically related to the mechanisms of aging. It is not therefore surprising that research in this field is growing exponentially in recent years, and sarcopenia has been placed in recent years in the forefront of research in geriatric medicine and gerontology.The Spanish Society of Geriatrics and Gerontology has recently created an Observatory of Sarcopenia, which aims to promote educational and research activities in this field. The first activity of the Observatory has been to offer the Spanish speaking scientific community a review of the current status of sarcopenia, that may allow unifying concepts and fostering interest in this promising field of geriatrics.  相似文献   
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The role of sex-steroid hormones, testosterone (T) and 17beta-estradiol (E2), on the humoral immune parameters of the teleost gilthead seabream Sparus aurata was studied attempting to deepen on the knowledge of the immune-reproductive system interactions. Fish were injected intraperitoneally with coconut oil containing different dosages of T (0, 2, or 5 microg g(-1) body weight [bw]) or E2 (0, 1, or 2 microg g(-1) bw) and sampled 1, 3, and 7 days later. Hormonal levels and immune parameters (complement, peroxidase and antiprotease activities and IgM levels) were determined in plasma. Plasma hormone levels peaked at 1 day post-injection decreasing thereafter. Treatment with T significantly increased both complement and peroxidase activities after 3 days of injection but antiprotease activity and IgM levels remained unchanged. Treatment with E2 enhanced complement activity 1 day post-injection while decreased it after 3 and 7 days. However, peroxidase activity increased at 3 and 7 days post-injection while total IgM levels decreased. Implications of T and E2 in the immune-reproductive system interactions were discussed.  相似文献   
95.

Background

There are few systematic studies on the prevalence of sarcopenia using the new diagnostic criteria in different geriatric care settings.

Objective

To estimate the prevalence of sarcopenia, using the European Working Group on Sarcopenia in Older People (EWGSOP) criteria in older subjects living in nursing homes and in those who attend geriatric outpatient clinics.

Material and methods

A single country multicentre study in two samples of older subjects: patients cared for in outpatient geriatric clinics, and individuals living in nursing homes. Data collected will include demographic variables, medical history, medication, geriatric syndromes, functional status (assessment of basic and instrumental activities of daily living), mobility, cognitive status, comorbidity, quality of life, nutritional status, and laboratory parameters. For the diagnosis of sarcopenia, 4 m walking speed, handgrip strength, and body composition measured by bioelectrical impedance analysis will be assessed.

Results

Using the EWGSOP algorithm, the prevalence of sarcopenia in an elderly Spanish population will be estimated. In addition, concordance and correlation between the three parameters included in the definition (muscle mass, muscle strength, and physical performance) will be analysed, using the different existing cut-off points, and examining the diagnostic accuracy of each. Finally, demographic, anthropometric and functional data that define subjects with sarcopenia will be investigated.

Conclusions

The ELLI study should improve knowledge on the prevalence and characteristics of sarcopenia in older people in our population.  相似文献   
96.
Global climate models suggest enhanced warming of the tropical mid and upper troposphere, with larger temperature rise rates at higher elevations. Changes in fire activity are amongst the most significant ecological consequences of rising temperatures and changing hydrological properties in mountainous ecosystems, and there is a global evidence of increased fire activity with elevation. Whilst fire research has become popular in the tropical lowlands, much less is known of the tropical high Andean region (>2000masl, from Colombia to Bolivia). This study examines fire trends in the high Andes for three ecosystems, the Puna, the Paramo and the Yungas, for the period 1982–2006. We pose three questions: (i) is there an increased fire response with elevation? (ii) does the El Niño‐ Southern Oscillation control fire activity in this region? (iii) are the observed fire trends human driven (e.g., human practices and their effects on fuel build‐up) or climate driven? We did not find evidence of increased fire activity with elevation but, instead, a quasicyclic and synchronous fire response in Ecuador, Peru and Bolivia, suggesting the influence of high‐frequency climate forcing on fire responses on a subcontinental scale, in the high Andes. ENSO variability did not show a significant relation to fire activity for these three countries, partly because ENSO variability did not significantly relate to precipitation extremes, although it strongly did to temperature extremes. Whilst ENSO did not individually lead the observed regional fire trends, our results suggest a climate influence on fire activity, mainly through a sawtooth pattern of precipitation (increased rainfall before fire‐peak seasons (t‐1) followed by drought spells and unusual low temperatures (t0), which is particularly common where fire is carried by low fuel loads (e.g., grasslands and fine fuel). This climatic sawtooth appeared as the main driver of fire trends, above local human influences and fuel build‐up cyclicity.  相似文献   
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99.
The maximum percentage of lysis of head-kidney non-specific cytotoxic cells (NCC) against mammalian tumour cells (L1210 and K562) in the marine teleost gilthead seabream (Sparus aurata L.) was studied. The present data indicate the short period of time necessary for gilthead seabream NCC to form conjugates and deliver a lethal hit. The maximum percentage of lysis observed demonstrates that seabream NCC activity against L1210 tumour cells is faster than against K562 tumour cells. This kinetic parameter suggests that fish NCC show a less efficient cytotoxic activity than their mammalian counterparts. The possibility of applying theoretical treatments to systems consisting of lower vertebrate non-specific cytotoxic cells and tumour targets, similar to those applied to mammals, is considered, and the phylogenetic implications of our findings are discussed.  相似文献   
100.
Inulin, a fructooligossacharide, is a prebiotic that plays an important role in the immune function in mammals, but it has never been assayed in other vertebrate groups. Thus, we have studied the inulin effects on the gilthead seabream (Sparus aurata L.) innate immune response both in vitro and in vivo. For the in vitro study, head-kidney leucocytes were incubated with inulin (ranging from 0 to 1000 microg ml(-1)) for 30, 90, 180 and 300 min and 24h and any effect was observed on leucocyte viability or the main innate cellular immune responses (leucocyte peroxidase, phagocytic, respiratory burst and natural cytotoxic activities). For the in vivo study, seabream specimens were fed for 1 or 2 weeks with a commercial diet supplemented with inulin: 0 (control), 5 or 10 g inulin kg(-1) diet (0.5 and 1%, respectively). Inulin produced a significant inhibition in phagocytosis and respiratory burst in leucocytes from specimens fed diets containing 0.5% or 1% of inulin for 1 week. Based on the present results, inulin does not seem to be a good immunostimulant for seabream, though its effects in other species and combined with other immunostimulans (i.e. probiotics) might be of great interest.  相似文献   
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