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1.
Caloric restriction reduces the incidence and progression of a broad spectrum of neoplastic diseases, yet little is known about the biochemical and molecular mechanisms involved. Profiles of enzyme activities of importance in cellular energy utilization were examined in 7,12-dimethylbenz[a]anthracene-induced (DMBA) mammary adenocarcinomas from rats fed ad libitum or calorically restricted diets. The diets provided equal nutrients except for fewer carbohydrate-derived calories; graded caloric restriction was 10, 20, 30 and 40%. The specific activities of hexokinase, pyruvate kinase, lactate dehydrogenase, glucose-6-phosphate dehydrogenase, malic enzyme and fructose-1,6-bisphosphatase were all elevated to varying degrees in both large palpable and small, non-palpable tumors from calorically restricted hosts compared to activities in tumors from ad libitum-fed rats. Phosphofructokinase activity was increased in palpable tumors from calorically restricted hosts but markedly reduced in non-palpable tumors. These results suggest adaptive or compensatory alterations in tumor enzyme profiles in response to the altered nutritional state of the host. 相似文献
2.
A Ferrari N Pacini C R Sirtori D Kritchevsky 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1988,188(1):108-111
Chenodeoxycholic and ursodeoxycholic acid are used widely for the treatment of gallstones. A possible drawback to their utility is their conversion to lithocholic acid, which has displayed histotoxicity and mutagenicity. The 7-oleyl esters of cheno- and ursodeoxycholic acid are not degraded by fecal bacteria and may represent safer means of treatment. 相似文献
3.
Several 7-acyl cheno- and ursodeoxycholic acids were obtained in good yields starting from the corresponding cheno- and ursodeoxycholic acids, by a diacylation-selective hydrolysis procedure. A superior method for the synthesis of the 7-oleyl derivatives, by a selective acylation procedure, is also presented. 相似文献
4.
This study was conducted to examine the psycho-emotional effects of repeated oral exposure to capsaicin, the principal active component of chili peppers. Each rat received 1 mL of 0.02% capsaicin into its oral cavity daily, and was subjected to behavioural tests following 10 daily administrations of capsaicin. Stereotypy counts and rostral grooming were significantly increased, and caudal grooming decreased, in capsaicin-treated rats during the ambulatory activity test. In elevated plus maze test, not only the time spent in open arms but also the percent arm entry into open arms was reduced in capsaicin-treated rats compared with control rats. In forced swim test, although swimming duration was decreased, struggling increased in the capsaicin group, immobility duration did not differ between the groups. Repeated oral capsaicin did not affect the basal levels of plasma corticosterone; however, the stress-induced elevation of plasma corticosterone was prolonged in capsaicin treated rats. Oral capsaicin exposure significantly increased c-Fos expression not only in the nucleus tractus of solitarius but also in the paraventricular nucleus. Results suggest that repeated oral exposure to capsaicin increases anxiety-like behaviours in rats, and dysfunction of the hypothalamic-pituitary-adrenal axis may play a role in its pathophysiology. 相似文献
5.
三氧化二砷对食管癌细胞增殖和热休克蛋白70表达的影响 总被引:2,自引:0,他引:2
目的:研究三氧化二砷(As2O3)对食管癌细胞增殖和热休克蛋白70(HSP70)表达的影响。方法:通过相差显微镜、流式细胞术、免疫细胞化学染色和免疫印迹分析等方法观察As2O3对人食管癌细胞株EC1的作用效果和作用机制。结果:与对照组相比,经2μmol/L和5μmol/Las2O3作用的细胞出现明显的生长抑制,G2/M期细胞比例增加;2μmol/Las2O3作用48h后经Ecl细胞HSP70(heat shock protein70)及HSC70(heat shock cognate protein70)表达均增加。结论:As2O3诱导食管癌细胞G2/M期阻滞抑制细胞增殖和生长;HSP70的升高是细胞对As2O3作用后出现的应激反应,并与细胞周期阻滞相关。 相似文献
6.
KB Cullberg T Christiansen SK Paulsen JM Bruun SB Pedersen B Richelsen 《Obesity (Silver Spring, Md.)》2013,21(3):454-460
Background:
Vascular growth is a prerequisite for adipose tissue (AT) development and expansion. Some AT cytokines and hormones have effects on vascular development, like vascular endothelial growth factor (VEGF‐A), angiopoietin (ANG‐1), ANG‐2 and angiopoietin‐like protein‐4 (ANGPTL‐4).Methods:
In this study, the independent and combined effects of diet‐induced weight loss and exercise on AT gene expression and proteins levels of those angiogenic factors were investigated. Seventy‐nine obese males and females were randomized to: 1. Exercise‐only (EXO; 12‐weeks exercise without diet‐restriction), 2. Hypocaloric diet (DIO; 8‐weeks very low energy diet (VLED) + 4‐weeks weight maintenance diet) and 3. Hypocaloric diet and exercise (DEX; 8‐weeks VLED + 4‐weeks weight maintenance diet combined with exercise throughout the 12 weeks). Blood samples and fat biopsies were taken before and after the intervention.Results:
Weight loss was 3.5 kg in the EXO group and 12.3 kg in the DIO and DEX groups. VEGF‐A protein was non‐significantly reduced in the weight loss groups. ANG‐1 protein levels were significantly reduced 22‐25% after all three interventions (P < 0.01). The ANG‐1/ANG‐2 ratio was also decreased in all three groups (P < 0.05) by 27‐38%. ANGPTL‐4 was increased in the EXO group (15%, P < 0.05) and 9% (P < 0.05) in the DIO group. VEGF‐A, ANG‐1, and ANGPTL‐4 were all expressed in human AT, but only ANGPTL‐4 was influenced by the interventions.Conclusions:
Our data show that serum VEGF‐A, ANG‐1, ANG‐2, and ANGPTL‐4 levels are influenced by weight changes, indicating the involvement of these factors in the obese state. Moreover, it was found that weight loss generally was associated with a reduced angiogenic activity in the circulation. 相似文献7.
N'Diaye A Chen GK Palmer CD Ge B Tayo B Mathias RA Ding J Nalls MA Adeyemo A Adoue V Ambrosone CB Atwood L Bandera EV Becker LC Berndt SI Bernstein L Blot WJ Boerwinkle E Britton A Casey G Chanock SJ Demerath E Deming SL Diver WR Fox C Harris TB Hernandez DG Hu JJ Ingles SA John EM Johnson C Keating B Kittles RA Kolonel LN Kritchevsky SB Le Marchand L Lohman K Liu J Millikan RC Murphy A Musani S Neslund-Dudas C North KE Nyante S Ogunniyi A Ostrander EA Papanicolaou G Patel S Pettaway CA 《PLoS genetics》2011,7(10):e1002298
Adult height is a classic polygenic trait of high heritability (h
2 ∼0.8). More than 180 single nucleotide polymorphisms (SNPs), identified mostly in populations of European descent, are associated with height. These variants convey modest effects and explain ∼10% of the variance in height. Discovery efforts in other populations, while limited, have revealed loci for height not previously implicated in individuals of European ancestry. Here, we performed a meta-analysis of genome-wide association (GWA) results for adult height in 20,427 individuals of African ancestry with replication in up to 16,436 African Americans. We found two novel height loci (Xp22-rs12393627, P = 3.4×10−12 and 2p14-rs4315565, P = 1.2×10−8). As a group, height associations discovered in European-ancestry samples replicate in individuals of African ancestry (P = 1.7×10−4 for overall replication). Fine-mapping of the European height loci in African-ancestry individuals showed an enrichment of SNPs that are associated with expression of nearby genes when compared to the index European height SNPs (P<0.01). Our results highlight the utility of genetic studies in non-European populations to understand the etiology of complex human diseases and traits. 相似文献
8.
A long‐term intensive lifestyle intervention and physical function: The look AHEAD Movement and Memory Study 下载免费PDF全文
9.
Janaína A Couto Karina LA Saraiva Cleiton D Barros Daniel P Udrisar Christina A Peixoto Juliany SB César Vieira Maria C Lima Suely L Galdino Ivan R Pitta Maria I Wanderley 《Reproductive biology and endocrinology : RB&E》2010,8(1):13
Background
The present study was designed to examine the effect of chronic treatment with rosiglitazone - thiazolidinedione used in the treatment of type 2 diabetes mellitus for its insulin sensitizing effects - on the Leydig cell steroidogenic capacity and expression of the steroidogenic acute regulatory protein (StAR) and cholesterol side-chain cleavage enzyme (P450scc) in normal adult rats. 相似文献10.
Tranah GJ Lam ET Katzman SM Nalls MA Zhao Y Evans DS Yokoyama JS Pawlikowska L Kwok PY Mooney S Kritchevsky S Goodpaster BH Newman AB Harris TB Manini TM Cummings SR;For the Health Aging Body Composition Study 《Biochimica et biophysica acta》2012,1817(9):1691-1700
The decline in activity energy expenditure underlies a range of age-associated pathological conditions, neuromuscular and neurological impairments, disability, and mortality. The majority (90%) of the energy needs of the human body are met by mitochondrial oxidative phosphorylation (OXPHOS). OXPHOS is dependent on the coordinated expression and interaction of genes encoded in the nuclear and mitochondrial genomes. We examined the role of mitochondrial genomic variation in free-living activity energy expenditure (AEE) and physical activity levels (PAL) by sequencing the entire (~16.5 kilobases) mtDNA from 138 Health, Aging, and Body Composition Study participants. Among the common mtDNA variants, the hypervariable region 2 m.185G>A variant was significantly associated with AEE (p=0.001) and PAL (p=0.0005) after adjustment for multiple comparisons. Several unique nonsynonymous variants were identified in the extremes of AEE with some occurring at highly conserved sites predicted to affect protein structure and function. Of interest is the p.T194M, CytB substitution in the lower extreme of AEE occurring at a residue in the Qi site of complex III. Among participants with low activity levels, the burden of singleton variants was 30% higher across the entire mtDNA and OXPHOS complex I when compared to those having moderate to high activity levels. A significant pooled variant association across the hypervariable 2 region was observed for AEE and PAL. These results suggest that mtDNA variation is associated with free-living AEE in older persons and may generate new hypotheses by which specific mtDNA complexes, genes, and variants may contribute to the maintenance of activity levels in late life. 相似文献