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91.
Free radicals produced by ulcerogenic agents affect the TCA cycle enzymes located in the outer membrane of the mitochondria. Upon induction with ulcerogens, peroxidation of membrane lipids bring about alterations in the mitochondrial enzyme activity. This indicates an increase in the permeability levels of the mitochondrial membrane. The ability of PSE to scavenge the reactive oxygen species results in restoration of activities of TCA cycle enzymes. NSAIDs interfere with the mitochondrial beta-oxidation of fatty acids in vitro and in vivo, resulting in uncoupling of mitochondrial oxidative phosphorylation process. This usually results in diminished cellular ATP production. The recovery of gastric mucosal barrier function through maintenance of energy metabolism results in maintenance of ATP levels, as observed in this study upon treatment with PSE. Membrane integrity altered by peroxidation is known to have a modified fatty acid composition, a disruption of permeability, a decrease in electrical resistance, and increase in flip-flopping between monolayers and inactivated cross-linked proteins. The severe depletion of arachidonic acid in ulcer induced groups was prevented upon treatment with PSE. The acid inhibitory property of the herbal extract enables the maintenance of GL activity upon treatment with PSE. The ability to prevent membrane peroxidation has been traced to the presence of active constituents in the PSE. In essence, PSE has been found to prevent mitochondrial dysfunction, provide mitochondrial cell integrity, through the maintenance of lipid bilayer by its ability to provide a hydrophobic character to the gastric mucosa, further indicating its ability to reverse the action of NSAIDs and mast cell degranulators in gastric mucosa. 相似文献
92.
Bhoopathy Dhivya Bhaskaran Ravi Latha Modhugoor Devendiran Raja Chirukandoth Sreekumar V. Leela 《Experimental & applied acarology》2014,63(1):85-92
In the current study, an attempt was made to encapsulate assembly pheromone using natural polymer, chitosan. Chitosan beads were prepared by incorporating assembly pheromone in conjunction with an acaricide, namely, deltamethrin. In the in vitro bioassay, the test beads attracted and killed 79 % of unfed larvae, 88 % of unfed nymphs and 61 % of unfed adults of the brown dog tick, Rhipicephalus sanguineus, in 24 h of exposure. Field trials were carried out to attract and kill the pre-parasitic environmental stages. The beads were dispersed onto specially designed devices and they were placed in infested kennels. The devices were observed after 10 days. 相似文献
93.
94.
95.
Beneficial effects of alpha linolenic acid rich flaxseed oil on growth performance and hepatic cholesterol metabolism in high fat diet fed rats 总被引:1,自引:0,他引:1
Vijaimohan K Jainu M Sabitha KE Subramaniyam S Anandhan C Shyamala Devi CS 《Life sciences》2006,79(5):448-454
The purpose of the study was to investigate the effect of flaxseed oil (FO), rich in alpha-linolenic acid (ALA) (18:3 n-3) on growth parameters and lipid metabolism of rats fed with high fat diet. High fat diet (HFD) resulted in significant alterations in hepatic lipids, increase in body weight gain and negative effect on lipoprotein metabolism. FO supplementation significantly lowered the increase in body weight gain, liver weight, plasma cholesterol, triglycerides, phospholipids, free fatty acids, high-density lipoprotein (HDL), low-density lipoprotein-cholesterol (LDL-C), very low-density lipoprotein (VLDL), LDL/HDL and TC/HDL ratio in HFD fed rats. FO significantly reduced the hepatic and plasma lipid levels indicating its hypolipidemic activity. On the other hand, oral administration of FO exhibited lower plasma lipoprotein profile as compared to HFD rats. Hepatic protection by FO is further substantiated by the normal liver histological findings in HFD fed rats. These data suggest that FO participate in the normal regulation of plasma lipid concentration and cholesterol metabolism in liver. No adverse effect of FO on growth parameters and plasma lipids in rats fed with fat-free diet. The results of the present study demonstrate that FO may be developed as a useful therapy for hyperlipidemia through reducing hepatic lipids, thereby proving its hypolipidemic activity. 相似文献
96.
97.
Helen Strongman Helena Carreira Bianca L. De Stavola Krishnan Bhaskaran David A. Leon 《PLoS medicine》2022,19(1)
BackgroundExcess mortality captures the total effect of the Coronavirus Disease 2019 (COVID-19) pandemic on mortality and is not affected by misspecification of cause of death. We aimed to describe how health and demographic factors were associated with excess mortality during, compared to before, the pandemic.Methods and findingsWe analysed a time series dataset including 9,635,613 adults (≥40 years old) registered at United Kingdom general practices contributing to the Clinical Practice Research Datalink. We extracted weekly numbers of deaths and numbers at risk between March 2015 and July 2020, stratified by individual-level factors. Excess mortality during Wave 1 of the UK pandemic (5 March to 27 May 2020) compared to the prepandemic period was estimated using seasonally adjusted negative binomial regression models. Relative rates (RRs) of death for a range of factors were estimated before and during Wave 1 by including interaction terms. We found that all-cause mortality increased by 43% (95% CI 40% to 47%) during Wave 1 compared with prepandemic. Changes to the RR of death associated with most sociodemographic and clinical characteristics were small during Wave 1 compared with prepandemic. However, the mortality RR associated with dementia markedly increased (RR for dementia versus no dementia prepandemic: 3.5, 95% CI 3.4 to 3.5; RR during Wave 1: 5.1, 4.9 to 5.3); a similar pattern was seen for learning disabilities (RR prepandemic: 3.6, 3.4 to 3.5; during Wave 1: 4.8, 4.4 to 5.3), for black or South Asian ethnicity compared to white, and for London compared to other regions. Relative risks for morbidities were stable in multiple sensitivity analyses. However, a limitation of the study is that we cannot assume that the risks observed during Wave 1 would apply to other waves due to changes in population behaviour, virus transmission, and risk perception.ConclusionsThe first wave of the UK COVID-19 pandemic appeared to amplify baseline mortality risk to approximately the same relative degree for most population subgroups. However, disproportionate increases in mortality were seen for those with dementia, learning disabilities, non-white ethnicity, or living in London.Helen Strongman and colleagues investigate the health and demographic factors associated with excess mortality during, as compared to before, the COVID-19 pandemic. 相似文献
98.
Plant exhibits various patterns of survival under salinity and their growth and development depend on their capacity to overcome the stress. Present investigation was focused on the response and regulation of the antioxidant defense system and the level of lipid peroxidation in Panicum miliacium and Panicum sumatrense under salt treatments. NaCl stress was imposed for 20 days after sowing of two Panicum species. The changes in the antioxidant enzyme activity like superoxide dismutase, catalase, peroxidase, and ascorbate peroxidase and the rate of lipid peroxidation level in terms of malondialdehyde (MDA) were recorded in both Panicum species. A great correlation exists between the antioxidant enzymes and lipid peroxidation. The defense mechanism activated in Panicum species studied was confirmed by the increased antioxidant enzyme activities under progressive NaCl stress. MDA content remained close to control at moderate NaCl concentrations and increased at higher salinities. Although lipid peroxidation increased in both Panicum species under salt stress the percent of increase was low in P. sumatrense indicating its salt-tolerant nature. Another possible conclusion is that improved tolerance to salt stress may be accomplished by increased capacity of antioxidative system. 相似文献
99.
K. Satyanarayana J. H. Yu G. Bhaskaran K. H. Dahm R. Meola 《Entomologia Experimentalis et Applicata》1991,59(2):135-143
At eclosion, the ovaries of female Corn earworm Heliothis zea do not contain mature eggs. Virgin-unfed females produced approximately 400 mature eggs in 8 days; mating or feeding doubled this number, and mating plus feeding more than tripled it. Females allatectomized or decapitated at day O matured few eggs. Egg production was restored by implantation of active corpora allata (CA) or by treatment with the juvenile hormone (JH) analogue methoprene at day 0. 20-Hydroxyecdysone, on the other hand, had no effect. Females in which the CA had been denervated or in which the median neurosecretory cells of the brain had been ablated at day O produced fewer eggs than sham-operated animals. These results indicate that egg maturation is controlled by JH and that continuous input from the brain is required for sustained CA activity for maintaining a high rates of egg maturation.The rate of JH biosynthesis by CA in vitro was determined with a radiochemical assay. The major hormones produced were JH-II and JH-III with small quantities of JH-I. The rates of JH synthesis were similar in all experimental groups which may indicate that the in vitro rate of JH synthesis does not reflect the actual state of CA activity in the female. 相似文献
100.
Wolfgang P. J. Dittus Shyamala M. Ratnayeke 《International journal of primatology》1989,10(3):215-234
Toque macaques (Macaca sinica),inhabiting natural forest at Polonnaruwa, Sri Lanka, are frequently injured in fights with conspecifics. The behavior of known
individuals when they were injured was compared to that after they had recovered their health. Thus, injured animals rested
and alloand autogroomed more, but they foraged less and initiated fewer aggressive episodes. They spent most time being sedentary
in the safety of arboreal refuges and reduced acrobatic movements by locomoting more often terrestrially. Other group members
showed no special tolerance (or altruism) toward injury victims during the costly and highly competitive activity of foraging
for food. In fact, some injured animals received more aggression, or lost dominance rank, and thereby had their competitive
abilities further impaired. Care for the injured was manifest mostly by grooming and wound cleaning. All hair in the area
surrounding a wound, as well as dirt, scabs, and fly larvae, were removed, and saliva was applied by licking the wound (wounds
so treated healed with no obvious signs of infection). (1) Injured macaques sought and received significantly more grooming
(owing to wound care); (2) the amount so received increased with the severity of the injury; and (3) the initiative of other
group members often compensated for a victim’s inability to solicit care. Juvenile males were especially attentive to injured
adult males, suggesting that they were investing in a social bond with these adults, which might reciprocate altruism toward
their juvenile caregivers in the future. Injured juvenile females received most care from their mothers. 相似文献