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71.
Bagheri J van den Berg-Emons RJ Pel JJ Horemans HL Stam HJ 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(3):691-696
The goal of this study was to compare the acute effects of whole-body vibration (WBV) delivered by 3 devices with different mechanical behavior on jump force (JF) and jump rate of force development (JRFD). Twelve healthy persons (4 women and 8 men; age 30.5 ± 8.8 years; height 178.6 ± 7.3 cm; body mass 74.8 ± 9.7 kg) were exposed to WBV for 15 and 40 seconds using 2 professional devices (power plate [PP; vertical vibration] and Galileo 2000 [GA; oscillatory motion around the horizontal axis in addition to vertical vibration]) and a home-use device [Power Maxx, PM; horizontal vibration]). The JF and JRFD were evaluated before, immediately after, and 5 minutes after WBV. The JF measured immediately after 40 seconds of vibration by the GA device was reduced (3%, p = 0.05), and JRFD measured after 5 minutes of rest after 40 seconds of vibration by the PM device was reduced (12%, p < 0.05) compared with the baseline value. The acute effects of WBV (15 or 40 seconds) on JF and JRFD were not significantly different among the 3 devices. In conclusion, our hypothesis that WBV devices with different mechanical behaviors would result in different acute effects on muscle performance was not confirmed. 相似文献
72.
M Noureddini J Verdi SA Mortazavi-Tabatabaei S Sharif A Azimi P Keyhanvar A Shoae-Hassani 《Cell biology international》2012,36(10):961-966
The potential of cell therapy is promising in nerve regeneration, but is limited by ethical considerations about the proper and technically safe source of stem cells. We report the successful differentiation of human EnSCs (endometrial stem cells) as a rich source of renewable and safe progenitors into high-efficiency cholinergic neurons. The extracellular signals of NGF (nerve growth factor) and bFGF (basic fibroblast growth factor) could induce cholinergic neuron differentiation. ChAT (choline acetyltransferase), MAP2 (microtubule associated protein 2) and NF-l (neurofilament L) increased after administration of bFGF and NGF to the EnSC cultures. trkC and FGFR2 (fibroblast growth factor receptor 2), which belong to the NGF and bFGF receptors respectively, were determined in populations of EnSCs. NGF, bFGF and their combination differentially influenced human EnSCs high efficiency differentiation. By inducing cholinergic neurons from EnSCs in a chemically defined medium, we could produce human neural cells without resorting to primary culture of neurons. This in vitro method provides an unlimited source of human neural cells and facilitates clinical applications of EnSCs for neurological diseases. 相似文献
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Lithium preparations are commonly used drug in treating mental disorders and bipolar diseases, but metal's cytotoxic mechanisms have not yet been completely understood. In this study, we investigated the cytotoxic mechanisms of lithium in freshly isolated rat hepatocytes. Lithium cytotoxicity were associated with reactive oxygen species (ROS) formation and collapse of mitochondrial membrane potential and cytochrome c release into the hepatocyte cytosol. All of the mentioned lithium-induced cytotoxicity markers were significantly (P?0.05) prevented by ROS scavengers, antioxidants, mitochondrial permeability transition pore sealing agents and adenosine triphosphate generators. Hepatocyte glutathione (GSH) was also rapidly oxidized and GSH-depleted hepatocytes were more resistant to lithium-induced oxidative stress markers. This suggests that lithium is activated by GSH. Our results also showed that CYP2E1 is involved in lithium oxidative stress mechanism. Lithium cytotoxicity was also associated with mitochondrial injuries initiated by increased ROS formation resulted from metal-CYP2E1 destructive interaction or metal-induced disruption of mitochondrial electron transfer chain. Methyl donors such as betaine, methionine, or folic acid prevented lithium cytotoxicity, and this suggests that this metal is detoxified by phase II metabolic methylation. In conclusion lithium-induced cytotoxicity could be attributed to oxidative stress and mitochondrial dysfunction. 相似文献
75.
Lastra G Whaley-Connell A Manrique C Habibi J Gutweiler AA Appesh L Hayden MR Wei Y Ferrario C Sowers JR 《American journal of physiology. Endocrinology and metabolism》2008,295(1):E110-E116
Renin-angiotensin-aldosterone system (RAAS) activation mediates increases in reactive oxygen species (ROS) and impaired insulin signaling. The transgenic Ren2 rat manifests increased tissue renin-angiotensin system activity, elevated serum aldosterone, hypertension, and insulin resistance. To explore the role of aldosterone in the pathogenesis of insulin resistance, we investigated the impact of in vivo treatment with a mineralocorticoid receptor (MR) antagonist on insulin sensitivity in Ren2 and aged-matched Sprague-Dawley (SD) control rats. Both groups (age 6-8 wk) were implanted with subcutaneous time-release pellets containing spironolactone (0.24 mg/day) or placebo over 21 days. Systolic blood pressure (SBP) and intraperitoneal glucose tolerance test were determined. Soleus muscle insulin receptor substrate-1 (IRS-1), tyrosine phosphorylated IRS-1, protein kinase B (Akt) phosphorylation, GLUT4 levels, and insulin-stimulated 2-deoxyglucose uptake were evaluated in relation to NADPH subunit expression/oxidase activity and ROS production (chemiluminescence and 4-hydroxy-2-nonenal immunostaining). Along with increased soleus muscle NADPH oxidase activity and ROS, there was systemic insulin resistance and reduced muscle IRS-1 tyrosine phosphorylation, Akt phosphorylation/activation, and GLUT4 expression in the Ren2 group (each P < 0.05). Despite not decreasing blood pressure, low-dose spironolactone treatment improved soleus muscle insulin signaling parameters and systemic insulin sensitivity in concert with reductions in NADPH oxidase subunit expression/activity and ROS production (each P < 0.05). Our findings suggest that aldosterone contributes to insulin resistance in the transgenic Ren2, in part, by increasing NADPH oxidase activity in skeletal muscle tissue. 相似文献
76.
M. A. Amoozegar J. Hamedi M. Dadashipour S. Shariatpanahi 《World journal of microbiology & biotechnology》2005,21(6-7):1237-1243
Summary Ten moderately halophilic spore-forming bacilli were isolated from saline soils in Iran and their intrinsic high-level resistance
to chromate, arsenate, tellurite, selenite, selenate and biselenite was identified by an agar dilution method. Minimum inhibitory
concentration (MIC) for each oxyanion was determined. All isolates were resistant to higher concentrations of arsenate. The
resistance level of the isolates to selenooxyanions was between 10 and 40 mM. Maximum and minimum tolerance against oxyanions
was seen in selenite and biselenite, respectively. Although toxic metal resistance in the isolates was not different from
non-halophilic bacteria that has been reported, unusual resistance to arsenate (250 mM), sodium chromate (75 mM) and potassium
chromate (70 mM) was observed. The results obtained in this study revealed that all isolates were obviously susceptible to
silver, nickel, zinc and cobalt, while seven isolates were resistant to lead. Susceptibility to copper and cadmium varied
among the isolates. Silver had the maximum toxicity, whereas lead and copper showed minimum toxicity. The impact of salinity
on the toxicity of oxyanions was also studied. Our results showed that in general an increase in salinity from 5% (w/v) to
15% (w/v) enhanced tolerance to toxic oxyanions. 相似文献
77.
BACKGROUND: Angiolymphoid hyperplasia with eosinophilia (ALHE) is an uncommon vascular inflammatory lesion usually involving the dermis or subcutaneous tissue of the head-neck region of middle-aged women. Histologically, this lesion shows a florid proliferation of vessels lined by particular endothelial cells and an inflammatory infiltrate composed of lymphocytes and eosinophils. CASE: A 30-year-old woman presented with multiple periauricular skin nodules. Fine needle aspiration cytology shows a mixed population of lymphoid cells with an admixture of eosinophils and large cells with vesicular nuclei and prominent nucleoli. A diagnosis of AHLE was confirmed on histopathologic examination. CONCLUSION: Various conditions, both benign and malignant, may mimic Kimura's disease clinically and on smears. These must be ruled out before making a diagnosis of Kimura's disease. The cytologic features of Kimura's disease have to be interpreted in the appropriate clinical setting in order to make a correct preoperative diagnosis. 相似文献
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Javad Tavakkoly Bazzaz Mahnaz Shojapoor Habibollah Nazem Parvin Amiri Hossein Fakhrzadeh Ramin Heshmat Maryam Parvizi Shirin Hasani Ranjbar Mahsa M. Amoli 《Molecular biology reports》2010,37(1):105-109
Methylenetetrahydrofolate reductase (MTHFR) polymorphism may play an important role in the pathophysiology of obesity and
diabetes accompanied by obesity due to its influence on plasma homocysteine levels. There are significant and sometimes very
strong relationship between levels of homocysteine and several multi-system diseases including CHD and CVA. To examine the
association between MTHFR gene C677T polymorphism in diabetes and obesity with serum homocysteine levels. A total of 682 subjects
were recruited in four groups (Normal, obese, diabetic and obese and diabetics). MTHFR gene C677T polymorphism was detected
using PCR-RFLP technique. Serum homocysteine levels were measured using HPLC. There was a significant increase in the mean
serum homocysteine levels in subjects carrying TT genotype (34.6 ± 26.5) compared to subjects carrying CC (15.1 ± 8) or CT
genotype (16.4 ± 7.8) (P < 0.000). We found no significant differences for MTHFR allele and genotype frequencies between different groups. Our data
have confirmed the association between serum homocysteine levels and MTHFR C677T genotype reported in other populations. 相似文献