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131.
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133.
α‐ l‐iduronidase gene‐based therapy using the phiC31 system to treat mucopolysaccharidose type I mice 下载免费PDF全文
Roberta Sessa Stilhano Priscila Keiko Matsumoto Martin Suely Maymone de Melo Vivian Yochiko Samoto Giovani Bravin Peres Yara Maria Correa da Silva Michelacci Flavia Helena da Silva Vanessa Gonçalves Pereira Vania D'Almeida Adriana Taveira da Cruz Miriam Galvonas Jasiulionis Sang Won Han 《The journal of gene medicine》2015,17(1-2):1-13
134.
Vivian Flinte Ethel Hentz Barbara Mascarenhas Morgado Anne Caruliny do Monte Lima Gabriel Khattar Ricardo Ferreira Monteiro Margarete Valverde de Macedo 《ZooKeys》2015,(547):119-132
The population phenology of the cassidines, Coptocycla
arcuata and Omaspides
trichroa, and the chrysomeline, Platyphora
axillaris, was studied at Serra dos Órgãos National Park, State of Rio de Janeiro, southeast Brazil. Monthly surveys of larvae and adults were conducted between 2008 and 2011 at approximately 1000 m altitude on their respective host plants, Cordia
polycephala (Boraginaceae), Ipomoea
philomega (Convolvulaceae) and Solanum
scuticum (Solanaceae). This is the first observation of larviparity and host record for Platyphora
axillaris. Although having different life history traits, all species showed similar phenologies. They were abundant from October to March, months of high temperatures and intense rainfall, with two distinct reproductive peaks in the same season. Abundance dropped abruptly during the coldest and driest months, from May to August. Frequently none of these species were recorded during June and July. This phenological pattern is similar to other Chrysomelidae living in subtropical areas of Brazil. Temperature and rainfall appear to be the major factors influencing the fluctuation of these three species. 相似文献
135.
Subacute calorie restriction and rapamycin discordantly alter mouse liver proteome homeostasis and reverse aging effects 下载免费PDF全文
Dao‐Fu Dai Ying A. Chiao Ellen K. Quarles Edward J. Hsieh David Crispin Jason H. Bielas Nolan G. Ericson Richard P. Beyer Vivian L. MacKay Michael J. MacCoss Peter S. Rabinovitch 《Aging cell》2015,14(4):547-557
Calorie restriction (CR) and rapamycin (RP) extend lifespan and improve health across model organisms. Both treatments inhibit mammalian target of rapamycin (mTOR) signaling, a conserved longevity pathway and a key regulator of protein homeostasis, yet their effects on proteome homeostasis are relatively unknown. To comprehensively study the effects of aging, CR, and RP on protein homeostasis, we performed the first simultaneous measurement of mRNA translation, protein turnover, and abundance in livers of young (3 month) and old (25 month) mice subjected to 10‐week RP or 40% CR. Protein abundance and turnover were measured in vivo using 2H3–leucine heavy isotope labeling followed by LC‐MS/MS, and translation was assessed by polysome profiling. We observed 35–60% increased protein half‐lives after CR and 15% increased half‐lives after RP compared to age‐matched controls. Surprisingly, the effects of RP and CR on protein turnover and abundance differed greatly between canonical pathways, with opposite effects in mitochondrial (mt) dysfunction and eIF2 signaling pathways. CR most closely recapitulated the young phenotype in the top pathways. Polysome profiles indicated that CR reduced polysome loading while RP increased polysome loading in young and old mice, suggesting distinct mechanisms of reduced protein synthesis. CR and RP both attenuated protein oxidative damage. Our findings collectively suggest that CR and RP extend lifespan in part through the reduction of protein synthetic burden and damage and a concomitant increase in protein quality. However, these results challenge the notion that RP is a faithful CR mimetic and highlight mechanistic differences between the two interventions. 相似文献
136.
Zeng N Li Y He L Xu X Galicia V Deng C Stiles BL 《Molecular cancer research : MCR》2011,9(12):1708-1717
The α-subunit of eukaryotic initiation factor 2 (eIF2α) is a key translation regulator that plays an important role in cellular stress responses. In the present study, we investigated how eIF2α phosphorylation can be regulated by a tumor suppressor PTEN (phosphatase and tensin homolog deleted on chromosome 10) and how such regulation is used by PTEN-deficient hepatocytes to adapt and cope with oxidative stress. We found that eIF2α was hyperphosphorylated when Pten was deleted, and this process was AKT dependent. Consistent with this finding, we found that the Pten-null cells developed resistance to oxidative glutamate and H(2)O(2)-induced cellular toxicity. We showed that the messenger level of CReP (constitutive repressor of eIF2α phosphorylation), a constitutive phosphatase of eIF2α, was downregulated in Pten-null hepatocytes, providing a possible mechanism through which PTEN/AKT pathway regulates eIF2α phosphorylation. Ectopic expression of CReP restored the sensitivity of the Pten mutant hepatocytes to oxidative stress, confirming the functional significance of the downregulated CReP and upregulated phospho-eIF2α in the resistance of Pten mutant hepatocytes to cellular stress. In summary, our study suggested a novel role of PTEN in regulating stress response through modulating the CReP/eIF2α pathway. 相似文献
137.
Low muscle strength is observed during the peri-and postmenopausal periods, when the secretion of ovarian hormones is drastically
reduced. It is also a predictive of adverse health events as well as incident mobility limitation and disability. The objective
of the present study is to study the biochemical and the histological changes in the skeletal muscle of premature menopause-induced
rats and the possible protective role of L-carnitine. Ovariectomized (OVX) rats were gavaged with L-carnitine (100 mg/kg)
daily for 60 days starting from the second post-operative day. Serum levels of estradiol and markers of skeletal muscle damage
(creatine kinase and lactic dehydrogenase activities) were determined. Light and electron microscopic study of the quadriceps
femoris muscle (QFM) specimens were done. OVX rats showed significant decrease in the serum estradiol level with significant
increase the markers for skeletal muscle damage. Histopathological examination of the QFM showed degenerated myofibers, apoptotic
changes and compensatory hypertrophy. Degenerated mitochondria, multiple lysosomes and lipid droplets among the damaged myofibrils
were also noticed. L-carnitine administration to the OVX rats resulted in non-significant change in the serum estradiol level
with significant attenuation of skeletal muscle damage either biochemically or histopathologically. In conclusion, L-carnitine
administration recovered muscle degeneration after ovariectomy. This finding suggested that L-carnitine could be recommended in the management of post-menopausal myopathy. 相似文献
138.
Levy MZ Small DS Vilhena DA Bowman NM Kawai V Cornejo del Carpio JG Cordova-Benzaquen E Gilman RH Bern C Plotkin JB 《PLoS computational biology》2011,7(9):e1002146
Vector-borne transmission of Chagas disease has become an urban problem in the city of Arequipa, Peru, yet the debilitating symptoms that can occur in the chronic stage of the disease are rarely seen in hospitals in the city. The lack of obvious clinical disease in Arequipa has led to speculation that the local strain of the etiologic agent, Trypanosoma cruzi, has low chronic pathogenicity. The long asymptomatic period of Chagas disease leads us to an alternative hypothesis for the absence of clinical cases in Arequipa: transmission in the city may be so recent that most infected individuals have yet to progress to late stage disease. Here we describe a new method, epicenter regression, that allows us to infer the spatial and temporal history of disease transmission from a snapshot of a population's infection status. We show that in a community of Arequipa, transmission of T. cruzi by the insect vector Triatoma infestans occurred as a series of focal micro-epidemics, the oldest of which began only around 20 years ago. These micro-epidemics infected nearly 5% of the community before transmission of the parasite was disrupted through insecticide application in 2004. Most extant human infections in our study community arose over a brief period of time immediately prior to vector control. According to our findings, the symptoms of chronic Chagas disease are expected to be absent, even if the strain is pathogenic in the chronic phase of disease, given the long asymptomatic period of the disease and short history of intense transmission. Traducción al espa?ol disponible en Alternative Language Text S1/A Spanish translation of this article is available in Alternative Language Text S1. 相似文献
139.
Facchini FD Vici AC Benassi VM Freitas LA Reis RA Jorge JA Terenzi HF Polizeli Mde L 《Bioprocess and biosystems engineering》2011,34(8):1027-1038
Fibrolytic enzyme production by Aspergillus japonicus C03 was optimized in a medium containing agro-industrial wastes, supplemented with peptone and yeast extract. A 23 full factorial composite and response surface methodology were used to design the experiments and analysis of results. Tropical
forages were hydrolyzed by A. japonicus C03 enzymatic extract in different levels, and they were also tested as enzymatic substrate. Optimal production to xylanase
was obtained with soybean bran added to crushed corncob (1:3), 0.01% peptone, and 0.2% yeast extract, initial pH 5.0, at 30 °C
under static conditions for 5 days of incubation. Optimal endoglucanase production was obtained with wheat bran added to sugarcane
bagasse (3:1), 0.01% peptone, and 0.2% yeast extract, initial pH 4.0, at 30 °C, for 6 days, under static conditions. Addition
of nitrogen sources as ammonium salts either inhibited or did not influence xylanase production. This enzymatic extract had
a good result on tropical forage hydrolyzes and showed better performance in the Brachiaria genera, due to their low cell wall lignin quantity. These results represent a step forward toward the use of low-cost agricultural
residues for the production of valuable enzymes with potential application in animal feed, using fermentation conditions. 相似文献
140.
Rachel P. Wildman Aileen P. McGinn Juan Lin Dan Wang Paul Muntner Hillel W. Cohen Kristi Reynolds Vivian Fonseca Mary‐Fran R. Sowers 《Obesity (Silver Spring, Md.)》2011,19(4):853-860
It remains unclear whether abdominal obesity increases cardiovascular disease (CVD) risk independent of the metabolic abnormalities that often accompany it. Therefore, the objective of this study was to evaluate the independent effects of abdominal obesity vs. metabolic syndrome and diabetes on the risk for incident coronary heart disease (CHD) and stroke. The Framingham Offspring, Atherosclerosis Risk in Communities, and Cardiovascular Health studies were pooled to assess the independent effects of abdominal obesity (waist circumference >102 cm for men and >88 cm for women) vs. metabolic syndrome (excluding the waist circumference criterion) and diabetes on risk for incident CHD and stroke in 20,298 men and women aged ≥45 years. The average follow‐up was 8.3 (s.d. 1.9) years. There were 1,766 CVD events. After adjustment for demographic factors, smoking, alcohol intake, number of metabolic syndrome components, and diabetes, abdominal obesity was not significantly associated with an increased risk of CVD (hazard ratio (HR) (95% confidence interval): 1.09 (0.98, 1.20)). However, after adjustment for demographics, smoking, alcohol intake, and abdominal obesity, having 1–2 metabolic syndrome components, the metabolic syndrome and diabetes were each associated with a significantly increased risk of CVD (2.12 (1.80, 2.50), 2.82 (1.92, 4.12), and 5.33 (3.37, 8.41), respectively). Although abdominal obesity is an important clinical tool for identification of individuals likely to possess metabolic abnormalities, these data suggest that the metabolic syndrome and diabetes are considerably more important prognostic indicators of CVD risk. 相似文献