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131.
Kopera I Tuz R Kotula-Balak M Schwarz T Koczanowski J Bilinska B 《Journal of experimental zoology. Part A, Ecological genetics and physiology》2008,309(3):117-126
In this study we thoroughly scrutinized testes morphology and investigated whether treatment of recipient boars with gonadotropin-releasing hormone (GnRH)-agonist deslorelin could alter the expression of 3beta-hydroxysteroid dehydrogenase (3beta-HSD), luteinizing hormone receptors (LHRs), and androgen receptors (ARs) in testicular cells. An implant containing 4.7 mg of the GnRH-agonist deslorelin was subcutaneously inserted into crossbred male pigs at 91 and 147 days of age. Testicular traits, morphology of the testes, the proteins' expression, and testosterone concentration in blood plasma were analyzed in all boars after slaughter at 175 days of age. Histological analysis revealed significant alterations in both the interstitial tissue and seminiferous tubules of experimental animals after 28 and 84 days of deslorelin treatment. The intensity of the AR immunostaining within the testis appeared as a function of the severity of testicular dysgenesis. Time-dependent action of deslorelin on the expression of LHR and 3beta-HSD in Leydig cells was also detected. Staining for LHR and 3beta-HSD was very weak or the Leydig cells were immunonegative. Concomitantly, a significant decrease in plasma testosterone level was found in both groups of deslorelin-treated boars when compared with the control group. This is the first report showing the cellular distribution of AR, LHR, and 3beta-HSD in testicular cells of deslorelin-treated boars. It is concluded that morphological and immunohistochemical studies are important for the evaluation of testicular histoarchitecture and steroidogenic function. Subsequently, the endocrine control of reproduction in the GnRH-agonist deslorelin-treated males will be better understood. 相似文献
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Edyta Skrzypek Ilona Czyczyło-Mysza Izabela Marcińska Maria Wędzony 《Plant Cell, Tissue and Organ Culture》2008,94(2):131-137
Anthers cultures of six Polish cultivars of pasture lupin (Lupinus L.) were examined for their androgenic response. Anthers with microspores at the uninucleate stage were isolated from flower
buds and cultured in liquid media. Better viability of androgenetic structures was obtained when donor plants had grown under
field as opposed to greenhouse conditions. A density of five anthers per 0.5 ml medium was more conducive to androgenetic
induction than 25 anthers per 0.5 ml medium. Addition of 5% maltose to the induction medium and culture at 25°C without pre-treatment
of flowers, buds or anthers promoted microspore release and division. The greatest frequency of androgenic callus, ~70% was
developed from cvs. Katon, Wat (white lupin), in contrast to cvs. Legat, Juno (yellow lupin), Polonez and Sonet (narrow-leafed
lupin) with callus induction ~30–40%. Despite various combinations of media tested, plant regeneration was not obtained from
anther derived callus. 相似文献
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Hugh Reyburn Redepmta Mbatia Chris Drakeley Ilona Carneiro Emmanuel Mwakasungula Ombeni Mwerinde Kapalala Saganda John Shao Andrew Kitua Raimos Olomi Brian M Greenwood Christopher J M Whitty 《BMJ (Clinical research ed.)》2004,329(7476):1212
Objective To study the diagnosis and outcomes in people admitted to hospital with a diagnosis of severe malaria in areas with differing intensities of malaria transmission.Design Prospective observational study of children and adults over the course a year.Setting 10 hospitals in north east Tanzania.Participants 17 313 patients were admitted to hospital; of these 4474 (2851 children aged under 5 years) fulfilled criteria for severe disease.Main outcome measure Details of the treatment given and outcome. Altitudes of residence (a proxy for transmission intensity) measured with a global positioning system.Results Blood film microscopy showed that 2062 (46.1%) of people treated for malaria had Plasmodium falciparum (slide positive). The proportion of slide positive cases fell with increasing age and increasing altitude of residence. Among 1086 patients aged ≥ 5 years who lived above 600 metres, only 338 (31.1%) were slide positive, while in children < 5 years living in areas of intense transmission (< 600 metres) most (958/1392, 68.8%) were slide positive. Among 2375 people who were slide negative, 1571 (66.1%) were not treated with antibiotics and of those, 120 (7.6%) died. The case fatality in slide negative patients was higher (292/2412, 12.1%) than for slide positive patients (142/2062, 6.9%) (P < 0.001). Respiratory distress and altered consciousness were the strongest predictors of mortality in slide positive and slide negative patients and in adults as well as children.Conclusions In Tanzania, malaria is commonly overdiagnosed in people presenting with severe febrile illness, especially in those living in areas with low to moderate transmission and in adults. This is associated with a failure to treat alternative causes of severe infection. Diagnosis needs to be improved and syndromic treatment considered. Routine hospital data may overestimate mortality from malaria by over twofold. 相似文献
136.
Pivi Rissanen Anja Franssila‐Kallunki Aila Rissanen 《Obesity (Silver Spring, Md.)》2001,9(10):637-643
Objective: We studied the effect of weight reduction on cardiac parasympathetic activity (PSA) in obese women. We also studied the relationship between the changes of PSA, resting energy expenditure (REE), and major cardiovascular risk factors. Research Methods and Procedures: Changes of cardiac vagal tone, an index of PSA, REE, and major cardiovascular risk factors, were measured in 52 healthy obese women after a 6‐month weight reduction. Ten of the women were remeasured at 12 and 24 months. Cardiac vagal tone was assessed by a vagal tone monitor and REE by indirect calorimeter. Results: Cardiac vagal tone increased significantly (p = 0.046), averaging a 9.5% weight loss in 6 months. The vagal tone increased further with weight loss during the following 6 months, and thereafter, it declined with weight regain. The increase of cardiac vagal tone correlated significantly with decreases of body weight, fat mass, waist circumference, serum insulin, and heart rate. REE adjusted for fat‐free mass and age did not change with weight loss and was not related to cardiac vagal tone at any time‐point. Discussion: Cardiac PSA activity increases with weight loss in obese women. This increase may not be maintained long‐term if body weight is regained. The rise of cardiac PSA is correlated with decreases of body fat mass, abdominal fat, serum insulin, and heart rate. Cardiac PSA is not related to REE. 相似文献
137.
Effects of Furfural on the Respiratory Metabolism of Saccharomyces cerevisiae in Glucose-Limited Chemostats 总被引:1,自引:0,他引:1 下载免费PDF全文
Ilona Srvri Horvth Carl Johan Franzn Mohammad J. Taherzadeh Claes Niklasson Gunnar Lidn 《Applied microbiology》2003,69(7):4076-4086
Effects of furfural on the aerobic metabolism of the yeast Saccharomyces cerevisiae were studied by performing chemostat experiments, and the kinetics of furfural conversion was analyzed by performing dynamic experiments. Furfural, an important inhibitor present in lignocellulosic hydrolysates, was shown to have an inhibitory effect on yeast cells growing respiratively which was much greater than the inhibitory effect previously observed for anaerobically growing yeast cells. The residual furfural concentration in the bioreactor was close to zero at all steady states obtained, and it was found that furfural was exclusively converted to furoic acid during respiratory growth. A metabolic flux analysis showed that furfural affected fluxes involved in energy metabolism. There was a 50% increase in the specific respiratory activity at the highest steady-state furfural conversion rate. Higher furfural conversion rates, obtained during pulse additions of furfural, resulted in respirofermentative metabolism, a decrease in the biomass yield, and formation of furfuryl alcohol in addition to furoic acid. Under anaerobic conditions, reduction of furfural partially replaced glycerol formation as a way to regenerate NAD+. At concentrations above the inlet concentration of furfural, which resulted in complete replacement of glycerol formation by furfuryl alcohol production, washout occurred. Similarly, when the maximum rate of oxidative conversion of furfural to furoic acid was exceeded aerobically, washout occurred. Thus, during both aerobic growth and anaerobic growth, the ability to tolerate furfural appears to be directly coupled to the ability to convert furfural to less inhibitory compounds. 相似文献
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By use of ion exchange chromatography we have isolated two discrete classes of “free” glycosaminoglycans (GAG) from human plasma. The GAG fractions were tested for their effects on two lipoprotein lipase (LPL) enzyme systems containing an apolipo-protein C-II activated emulsion as the triglyceride substrate and bovine serum albumin as the free fatty acid acceptor. The low-charge GAG (Fraction I) had essentially no effect on the LPL reaction. The high-charge GAG (Fraction II) stimulated the LPL reaction 100 to 300%. The GAG composition of each fraction was investigated with chemical and enzymatic techniques. Fraction I consisted of low-charge chondroitin sulfate noncovalently bound to protein. Fraction II consisted of a mixture of high-charge GAG non-covalently bound to protein. Degradation with nitrous acid eliminated the ability of high-charge GAG to stimulate LPL. This and other evidence suggests that the high-charge GAG in human plasma responsible for LPL activation is heparan sulfate (HS). We suggest that plasma HS may modulate triglyceride clearance mechanisms by its interaction with LPL. 相似文献