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71.
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A Brown V L Yu M H Magnussen R M Vickers G M Garrity E M Elder 《Applied microbiology》1982,43(3):725-726
Tatlockia (Legionella) micdadei, the Pittsburgh pneumonia agent, was isolated from a hospital shower. Although it was not possible, at the current time, to establish an epidemiological link to disease acquisition, this information may be significant because it provides further evidence that a water-associated reservoir of this organism exists within the hospital. 相似文献
73.
Human organ slices, an in vitro model representing the multicellular and functional features of in vivo tissue, is a promising model for characterizing mechanisms of drug-induced organ injury and for identifying biomarkers of organ injury. Target organ injury is a significant clinical issue. In vitro models, which compare human and animal tissue to improve the extrapolation of animal in vivo studies for predicting human outcome, will contribute to improving drug candidate selection and to defining species susceptibilities in drug discovery and development programs. A critical aspect to the performance and outcome of human organ slice studies is the use of high quality tissue, and the use of culture conditions that support optimum organ slice survivability, in order to accurately reproduce mechanisms of organ injury in vitro. The attribute of organ slices possessing various cell types and interactions contributes to the overall biotransformation, inflammatory response and assessment of injury. Regional differences and changes in morphology can be readily evaluated by histology and special stains, similar to tissue obtained from in vivo studies. The liver is the major organ of which slice studies have been performed, however the utility of extra-hepatic derived slices, as well as co-cultures is increasing. Recent application of integrating gene expression, with human organ slice function and morphology demonstrate the increased potential of this model for defining the molecular and biochemical pathways leading to drug-induced tissue changes. By gaining a more detailed understanding of the mechanisms of drug-induced organ injury, and by correlating clinical measurements with drug-induced effects in the in vitro models, the vision of human in vitro models to identify more sensitive and discriminating markers of organ damage is attainable. 相似文献
74.
EO Ogueji CD Nwani SC Iheanacho CE Mbah CO Okeke A Yaji 《African Journal of Aquatic Science》2018,43(3):293-303
Indiscriminate discharge of pharmaceutical waste into the aquatic ecosystem may pose serious health challenges to aquatic biota. The effect of acute exposure to ibuprofen was evaluated using changes in behaviour and haematological parameters under static bio-assay method in Clarias gariepinus. Test specimens were exposed to acute concentrations of ibuprofen (0.28, 0.33, 0.38, 0.43 and 0.48 mg l?1) for 24, 48, 72 and 96 h durations respectively. Behavioural and phenotypic changes were observed in surviving fish. There were significant (p < 0.05) concentration and duration-dependent increases in erythrocyte (RBC), haemoglobin (Hb), pack cell volume (PCV) and leukocytes (WBC) in treated fish compared to the control. Insignificant decreases (p > 0.05) in mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) were observed in treated fish compared to the control. Ibuprofen elicited dose and duration- dependent decrease in neutrophil counts with the decreases being significant (p < 0.05) in the higher doses of 0.43 and 0.48 mg l?1. Ibuprofen did not elicit any significant changes in monocytes, basophils and eosinophils. Changes observed in this study showed that ibuprofen negatively affected the health of the fish and we recommend that discharge of ibuprofen into the aquatic environment should be monitored and controlled. 相似文献
75.
Maternal obesity is associated with obesity and metabolic disorders in offspring. However, intervention strategies to reverse or ameliorate the effects of maternal obesity on offspring health are limited. Following maternal undernutrition, taurine supplementation can improve outcomes in offspring, possibly via effects on glucose homeostasis and insulin secretion. The effects of taurine in mediating inflammatory processes as a protective mechanism has not been investigated. Further, the efficacy of taurine supplementation in the setting of maternal obesity is not known. Using a model of maternal obesity, we examined the effects of maternal taurine supplementation on outcomes related to inflammation and lipid metabolism in mothers and neonates. Time-mated Wistar rats were randomised to either: 1) control : control diet during pregnancy and lactation (CON); 2) CON supplemented with 1.5% taurine in drinking water (CT); 3) maternal obesogenic diet (high fat, high fructose) during pregnancy and lactation (MO); or 4) MO supplemented with taurine (MOT). Maternal and neonatal weights, plasma cytokines and hepatic gene expression were analysed. A MO diet resulted in maternal hyperinsulinemia and hyperleptinemia and increased plasma glucose, glutamate and TNF-α concentrations. Taurine normalised maternal plasma TNF-α and glutamate concentrations in MOT animals. Both MO and MOT mothers displayed evidence of fatty liver accompanied by alterations in key markers of hepatic lipid metabolism. MO neonates displayed a pro-inflammatory hepatic profile which was partially rescued in MOT offspring. Conversely, a pro-inflammatory phenotype was observed in MOT mothers suggesting a possible maternal trade-off to protect the neonate. Despite protective effects of taurine in MOT offspring, neonatal mortality was increased in CT neonates, indicating possible adverse effects of taurine in the setting of normal pregnancy. These data suggest that maternal taurine supplementation may ameliorate the adverse effects observed in offspring following a maternal obesogenic diet but these effects are dependent upon prior maternal nutritional background. 相似文献
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The in-vivo performance of a new disposable parallel flow countercurrent type of artificial kidney has been compared with that of the modified four-layered Kiil dialyser. The dialysance of urea and endogenous creatinine in the former was significantly better than in the latter for similar blood flow rates, and, moreover, unlike the dialysance with the Kiil dialyser it continued to improve over 12 hours. Among 100 disposable artificial kidneys tested no failure occurred from blood leaks despite the use of high negative pressures in the dialysate compartment. No pyrogen reactions were observed.These new artificial kidneys were ready for use in less than one-seventh of the time taken to prepare the conventional Kiil dialyser. Other advantages are their low priming volumes, the lack of a pump in the blood line, and the reduced risk of infection. 相似文献
79.
MaleHeliothis virescens (F.) (Lepidoptera: Noctuidae) were made to fly into a uniformly white and translucent tube within a large wind tunnel while responding to sex pheromone. Different visual patterns placed within the tube greatly affected the ability of the male moths to maintain upwind progress or remain oriented to the wind while in contact with the plume. Over 89% of males attempting to fly through a blank tube, lacking visual patterns, became disoriented, the males gaining or losing altitude and repeatedly hitting the sides of the tube. Patterns of 20–40 dots placed on the sides of the tube at or slightly above plume level resulted in high levels of sustained upwind flight (47–74%) relative to patterns placed directly below (30–40%), directly above (35%), or slightly below the level of the flight path (26–44%). Optimal upwind progression in pheromone-responding males occurred when image motion could be resolved both transversely (T), orthogonally to the longitudinal axis of the body relative to the horizontal plane of the environment, and longitudinally (L), along the body axis. Even very sparse patterns (single rows of dots) could elicit high levels of sustained upwind flight (53–63%) when positioned within the tube such that the males' movements would create both L and T image motion. However, successful negotiation of the tube was also unexpectedly facilitated by patterns apparently providing no horizontal transverse component for flying males but providing longitudinal flow while centering the moth in the plume through a symmetrical left-right input (4–40%). 相似文献
80.
Adrian?H.?NicholasEmail author Robert?N.?Spooner-Hart Richard?A.?Vickers 《BioControl》2005,50(2):271-291
Woolly aphid (Eriosoma lanigerum Hausmann) (Hemiptera: Aphididae), was monitored over three growing seasons (1995--1998) to assess its abundance and management under apple IPM programs at Bathurst on the Central Tablelands of NSW, Australia. Woolly aphid infestations were found to be extremely low in IPM programs utilising mating disruption and fenoxycarb for codling moth Cydia pomonella L. (Lepidoptera: Tortricidae) control. This was the direct result of increased numbers of natural enemies. No insecticides were applied for woolly aphid control. Under the IPM strategies tested the principal control agent was identified as European earwig (Forficula auricularia L.) (Dermaptera: Forficulidae). Earwigs in combination with Aphelinus mali (Haldeman) (Hymenoptera: Aphelinidae) reduced woolly aphid infestations below the action threshold set by commercial growers. However, A. mali together with other flying natural enemies, e.g., ladybirds, lacewings and hoverflies, did not provide commercially acceptable control of woolly aphid in the absence of earwigs. Under the conventional spray program, using the broad-spectrum insecticide azinphos-methyl for codling moth control, the level of woolly aphid infestation increased with each successive season and biological control was not established. When azinphos-methyl was withdrawn, natural enemies migrated in and provided control of woolly aphid within one season. This is the first study to show that the biological control of woolly aphid can be achieved in a commercially viable IPM program. 相似文献