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2.
Cachexia is a multifactorial wasting syndrome most common in patients with cancer that is characterized by the uncontrolled loss of adipose and muscle mass. We show that the inhibition of lipolysis through genetic ablation of adipose triglyceride lipase (Atgl) or hormone-sensitive lipase (Hsl) ameliorates certain features of cancer-associated cachexia (CAC). In wild-type C57BL/6 mice, the injection of Lewis lung carcinoma or B16 melanoma cells causes tumor growth, loss of white adipose tissue (WAT), and a marked reduction of gastrocnemius muscle. In contrast, Atgl-deficient mice with tumors resisted increased WAT lipolysis, myocyte apoptosis, and proteasomal muscle degradation and maintained normal adipose and gastrocnemius muscle mass. Hsl-deficient mice with tumors were also protected although to a lesser degree. Thus, functional lipolysis is essential in the pathogenesis of CAC. Pharmacological inhibition of metabolic lipases may help prevent cachexia.  相似文献   
3.
The hormone profile of Sarotherodon mossambicus (Peters) under endosulfan (an organochlorine pesticide) toxicity was investigated by estimating the serum levels of T3 (triiodothyronine), T4 (thyroxine), cortisol, prolactin and insulin in control and sub-lethal (0.001 mg L−1) endosulfan-exposed fish for 1, 6, 12, 24 h and 5 days. Exposure of fish to sub-lethal concentration of endosulfan caused varying changes in the levels of serum hormones studied. Based on the results obtained, it was concluded that (i) the fish registered an increased metabolic activity during the initial period followed by an adaptive lowering of metabolic rate as indicated by changes in the serum T3 and T4 levels, (ii) the fish showed an adaptive stress response as indicated by the reduced cortisol level which could be probably due to severe interrenal exhaustion, (iii) the increased serum prolactin levels in the fish under endosulfan exposure is indicative of a possible action of prolactin on gills and kidney towards hydromineral regulation in the fish body under pesticide stress, (iv) the fish adaptively increases its serum insulin level thereby registering a possible adaptive hypoglycemic role of the hormone to favour the transport of glucose to different tissues besides a possible lipogenic activity of the higher insulin level in fish tissue under pesticide toxicity and (v) the fish appears to exhibit a possible adaptive recovery response in its hormone profile following prolonged exposure for 24 h and 5 days.  相似文献   
4.
Adaptive changes in the levels of carbohydrate metabolites, glucose, glycogen and lactic acid, were studied in a freshwater edible fish, Sarotherodon mossambicus exposed to a carbamate fungicide, ziram. Based on the results obtained, it was concluded that the fish showed (i) adaptive utilization of stored glycogen, particularly in liver tissue; (ii) adaptive accumulation of glycogen in muscle and heart tissues, probably by glyconeogenesis and (iii) adaptive mechanism of operation of ‘diving syndrome’, to meet the stress of the pollutant under sub-lethal exposure. © 1998 SCI.  相似文献   
5.
The individual and combined effects of dimecron (an organophosphate pesticide) and ziram (a carbamate fungicide) on the levels of serum prolactin and selected minerals (Ca, P, and Mg) are studied in an edible freshwater fish, Oreochromis mossambicus (Peters) exposed to sub-lethal concentrations of individual dimecron (0.002 mL L−1) and ziram (0.008 mL L−1) and combined 1:4 mixture of dimecron-ziram (0.01 mL L−1) for 24, 48, and 72 h. Exposure of fish to sub-lethal concentration of individual and mixture of dimecron and ziram caused changes in the levels of serum prolactin and minerals studied compared to control fishes. Based on the results obtained, it was concluded that the individual exposures of dimecron and ziram comparatively manifested higher toxic effects (than the combined exposure) by reducing prolactin levels and loss of mineral contents. These changes may result in a severe osmoregulatory problem.  相似文献   
6.
Solanum trilobatum L. is an Indian medicinal plant containing rich amount of steroidal glyco-alkoloids that can be used as precursor for commercial steroid production. Two efficient marker systems such as Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeats (ISSR) were used for the first time to assess the genetic diversity across 14 S. trilobatum accessions obtained from five South Indian states. Twenty out of 60 RAPD primers generated 189 distinct bands of which 160 were polymorphic with an average of 8 polymorphic bands per primer. A maximum of up to 15 fragments were amplified with an average of 9.45 bands per primer and the amplicons varied in size between 100 and 3,000 bp. The percentage of polymorphism ranged from 55.5 to 100, with an average of 84.6. ISSR profiling using 7 out of 20 primers amplified 83 bands and the number of amplified fragments varied from 2 to 16 with a size range of 200–1,800 bp. Totally 72 polymorphic bands were obtained using 7 ISSR primers at an average of 10.28 polymorphic bands per primer. Polymorphism percentage varied from 50 to 100 among the selected accessions resulting in an average percentage of polymorphism of 86.7. The PIC values ranged from 0.49 to 0.93 for RAPD and 0.16 to 0.90 for ISSR primers. The study pointed out that ISSR markers were more efficient than RAPD markers in evaluating the degree of genetic variation in S. trilobatum. The UPGMA cluster analysis grouped all Tamil Nadu accessions in one cluster and other state accessions in another cluster. The Principal component analysis also substantiates this clustering pattern. Thus the phylogenetic relationship and a high genetic variation revealed in the present study could provide a baseline data for conservation and improvement of this plant in future. Also the molecular markers identified in this study will be helpful in authentication of this species to prevent adulteration in herbal medicine.  相似文献   
7.
The activity levels of glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) enzymes were estimated in liver, muscle and brain tissues of the fish, Sarotherodon mossambicus (Peters), which had been exposed to sub-lethal (3 mg litre−1) and lethal (25 mg litre−1) concentrations of the carbamate insecticide carbaryl. Based on the results obtained, the changes in GOT and GPT levels in liver, muscle and brain following different periods of sub-lethal and lethal carbaryl exposures suggested that S mossambicus showed adaptive elevation in the activity levels of the two aminotransferase enzymes in the tissues, thereby probably aiding gluconeogenesis through transamination of glucogenic amino acids to meet the energy demand under carbaryl toxicity. © 1999 Society of Chemical Industry  相似文献   
8.
1. Japanese quail eggs from moderately heavier sires showed superior fertility; while fertile eggs from moderately heavier dams hatched slightly better than the eggs from lighter dams.

2. Higher rates of fertility and hatchability of Japanese quail eggs were observed from parents of 10 to 19 weeks of age, with peak fertility and hatchability at 14 and 12 weeks of age, respectively.

3. Sex ratios of 1:2 to 1:5 gave comparable fertility and hatchability results.

4. The hatching performance of quail eggs from cage and deep litter reared breeders was comparable.

5. Fertility and hatchability were directly proportional to the egg weight.

6. Quail egg shell colour, tints and blotches were found to influence hatching performance.

7. Storing quail eggs at 16 ± 2°C and 75 ± 5% relative humidity for more than 4 d reduced hatchability.

8. Hatchability of eggs stored at room temperature was improved if they were sealed in polyethylene bags.

9. Provision of light during the first 14 d of incubation resulted in a photo‐acceleration of about 3.2 h.  相似文献   

9.
Acidic deposition has caused a depletion of calcium (Ca) in the northeastern forest soils. Wollastonite (Ca silicate) was added to watershed 1 (WS1) at the Hubbard Brook Experimental Forest (HBEF) in 1999 to evaluate its effects on various functions of the HBEF ecosystem. The effects of Ca addition on foliar soluble (extractable in 5% HClO4) ions, chlorophyll, polyamines, and amino acids were studied in three hardwood species, namely sugar maple, yellow birch, and American beech. We further analyzed these effects in relation to elevation at Ca-supplemented WS1 and reference WS3 watersheds. Foliar soluble Ca increased significantly in all species at mid and high elevations at Ca-supplemented WS1. This was accompanied by increases in soluble P, chlorophyll, and two amino acids, glutamate and glycine. A decrease in known metabolic indicators of physiological stress (i.e., the amino acids, arginine and γ-aminobutyric acid (GABA), and the diamine, putrescine) was also observed. In general, these changes were species-specific and occurred in an elevation dependent manner. Despite an observed increase in Ca at high elevation for all three species, only sugar maple exhibited a decrease in foliar putrescine at this elevation indicating possible remediation from Ca deficiency. At higher elevations of the reference WS3 site, foliar concentrations of Ca and Mg, as well as Ca:Mn ratios were lower, whereas Al, putrescine, spermidine, and GABA were generally higher. Comparison of metabolic data from these three species reinforces the earlier findings that sugar maple is the most sensitive and American beech the least sensitive species to soil Ca limitation. Furthermore, there was an increase in sensitivity with an increase in elevation.  相似文献   
10.
A tree diversity inventory was carried out in urban green spaces (UGSs) of Chennai metropolitan city, India. This inventory aims to study the diversity, density and richness of trees in UGSs of Chennai. A total of one hundred 10 m × 10 m (total 1 ha) plots were laid to reveal tree diversity and richness of UGSs. Trees with ≥10 cm girths at breast height (gbh) were inventoried. We recorded 45 species in 42 genera and 21 families. Caesalpiniaceae and Fabaceae each with 6 species dominated the study area followed by Arecaceae (3). Density and stand basal area of the present study were 500 stems ha?1 and 64.16 m2, respectively. Most of the inventoried trees were native (31 species) and deciduous (28 species). Fabaceae and Caesalpiniaceae dominated the present study area in terms of stand basal area and density. The Shannon diversity index and evenness of study area were 2.79 and 0.73, respectively. The most important species and families based on species important value index (IVI) and family important value index were Albizia saman, Polyalthia longifolia and Azadirachta indica; Fabaceae, Caesalpiniaceae and Annonaceae respectively. We find Chennai's urban forest is relatively superior to many urban forests of the world in terms of stand basal area and species richness. Results emphasize the importance of enhancement of urban green spaces in Chennai metropolitan city.  相似文献   
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