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91.
Protective effect of 6-MFA, an interferon inducer and antiviral agent of fungal origin, was investigated against the neurotoxic effects induced by acrylamide in rats. Animals of 6-MFA (2.5, 5, 10 mg/100 gm, i.p.) pretreated plus acrylamide (ACR) group exhibited a reduction in development of hind limb paralysis which was 34, 25 and 20 (%) with increasing doses of 6-MFA respectively. Corpus striatal dopamine binding was significantly raised in the ACR treated rats while 6-MFA (10 mg) plus ACR group showed no significant change, in comparison to respective controls. Increased binding in the 6-MFA (2.5, 5 mg) pretreated plus ACR group was also evident. Glutathione-s-transferase (GST) activity was markedly reduced (66%) in ACR alone rats while no change was noted in rats pretreated with either dose of 6-MFA alone. However, a significant reversal was noted in animals of 6-MFA plus ACR group in a dose related manner. Conservation of glutathione levels and involvement of microglia, gamma-interferon and other lymphokines has been suggested for the observed protective effect of 6-MFA against neurotoxicity of ACR.  相似文献   
92.
An improved direct transformation method via particle bombardment of split-immature zygotic embryo explants with intact embryonic axis is reported. This method involves abiotic stress (cold treatment and plasmolysis) treatments of explants prepared from immature embryos of 8–10 mm size for improved somatic embryogeneis. Transgenic events were produced using optimized bombardment conditions and selection with hygromycin or glufosinate. Transgenic somatic embryos developed within as little as 4 weeks after bombardment of explants. Transgenic plants were regenerated 4–5 months after bombardment and the entire process from bombardment to T1 seed production took 7–9 months. Plants regenerated from the system were fertile and showed more than 90% heritability of the transgene to the next generation. Transformation frequencies of 5.4 and 2.7% (based on the number of bombarded split-immature embryo explants) were observed with hygromycin and glufosinate selection, respectively.  相似文献   
93.
P. S. Dubey  L. P. Mall 《Oecologia》1972,10(2):105-110
Summary Merremia gangetia Linn. (Cuf) is one of the most important weeds invading cultivated lands of India. Temperature, both high (45° C) and low (15° C) exhibit a definite role in development of the weed, particularly during germination. Higher tempeeratures (45° C) during dry storage appeared to be the main factor in laboratory experiments as well as in nature. Low temperature induced secondary dormancy and its removal by incubation at 35° C helps to explain the ecological mechanism through which the weed endures winter conditions. Germination of buried seeds confirm that the atmospheric conditions were found to be more effective in upper layers of soil. Ecological adaptations of this weed via germination requirements are assessed in the paper.  相似文献   
94.
Cyanobacteria are ecologically one of the most prolific groups of photosynthetic prokaryotes in marine and freshwater habitats. They are primary producer microorganisms and are involved in the production of important secondary metabolites, including toxic compounds such as cyanotoxins. Environmental conditions promote massive growth of these microbes, causing blooms that can have critical ecological and public health implications. In this highlight, we discuss some of the approaches being addressed to prevent these blooms, such as control of nutrient loading, treatments to minimize growth or monitoring interactions with other species.  相似文献   
95.
96.
Several experimental models of cardiac hypertrophy were investigated in rats: 1. mild hypertrophy induced by physical exercise (18 weeks), 2. mild hypertrophy induced by renovascular hypertension (24 weeks), 3. moderate hypertrophy induced by renovascular hypertension in diabetic and non-diabetic animals (8 weeks), 4. moderate hypertrophy induced by renovascular hypertension in diabetic and non-diabetic animals (12 weeks), 5. moderate hypertrophy induced by thyroxin application (4 weeks), 6. mild hypertrophy in chronic uremia (5/6 nephrectomy, 3 weeks). It is concluded from quantitative stereological parameters of the left ventricular papillary muscles that 1. in hypertrophic hearts myocardial blood flow and oxygen consumption, respectively, rather than the size of muscle fibres determine the capillary supply of the myocardium, 2. interstitial fibrosis occurs in hypertrophy induced by chronic pressure overload and depends on degree and duration of hypertension, 3. the extent of interstitial fibrosis in hypertension is magnified by diabetes mellitus, and 4. the interstitial fibrosis which occurs in chronic uremia is not caused by hypertension.  相似文献   
97.
Summary The mineral structure and its dynamics in forest ecosystems have been undertaken by a number of workers. Such studies are meagre for tropical grassland. The purpose of this study was to ascertain the nutrient structure for the producer components, and to estimate the annual uptake, retention and release for N, P, K and Ca. Data for these elements are given for plant and soil. The soil contains many more times nutrient than held by plant biomass. Inventory of the minerals indicates that, of the four elements i.e. N, P, K and Ca studied, annually about 58, 16, 18 and 38 kg/ha, respectively are taken up by the grassland, of which 29, 7, 6 and 23 kg/ha are released and about 29, 9, 12 and 14 kg/ha are retained in the vegetation compartments. re]19750516  相似文献   
98.
Proteome analysis of human substantia nigra in Parkinson's disease   总被引:1,自引:0,他引:1  

Background  

Parkinson's disease (PD) is the most common neurodegenerative disorder involving the motor system. Although not being the only region involved in PD, affection of the substantia nigra and its projections is responsible for some of the most debilitating features of the disease. To further advance a comprehensive understanding of nigral pathology, we conducted a tissue based comparative proteome study of healthy and diseased human substantia nigra.  相似文献   
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