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91.
Antidiarrhoeal activity of Rhus javanica ripen fruit extract in albino mice   总被引:1,自引:0,他引:1  
Tangpu V  Yadav AK 《Fitoterapia》2004,75(1):39-44
The antidiarrhoeal effects of the methanolic extract of Rhus javanica ripen fruits (MERJ) were investigated by employing four experimental models of diarrhoea in Swiss albino mice. MERJ treated mice, showed significant reduction in the faecal output and protected them from castor oil-induced diarrhoea. The extract also reduced the intestinal fluid secretion induced by MgSO4 and gastrointestinal motility after charcoal meal administration in the albino mice. No mortality and visible signs of general weakness was observed in the mice following the test extract administration up to 2000 mg/kg dose.  相似文献   
92.
Seeds of two coastal sand dune wild legumes, Canavalia cathartica and Canavalia maritima from the west coast of India were analyzed for their nutritional and antinutritional properties. The seeds contained 35.5 and 34.1% crude protein, 52.8 and 50.5% crude carbohydrates, 1.3 and 1.7% crude lipids and 3.1 and 3.5% ash content, respectively. Among the minerals, potassium was the highest followed by phosphorus. Globulins and albumins constituted the major seed proteins of both plants. Most of the essential amino acids were at adequate levels. Although the crude lipids were below 2%, the unsaturated fatty acids were high. Seeds did not contain tannins and trypsin inhibitors. The levels of total phenolics were low, but showed high hemagglutination activity. The nutritional properties of these seeds have been compared with other Canavalia spp. and wild unconventional or tribal legumes. Overall, the study results suggest that the seeds of C. cathartica and C. maritima possess potential nutritive value particularly higher protein, essential amino acids and low levels of antinutritional factors. These wild legumes are adapted to low nutrient, high saline and drought conditions of the coastal sand dunes; their conservation and domestication are warranted as potential alternative sources of protein.  相似文献   
93.
Commiphora wightii (Arn.) Bhandari syn. C. mukul Engl. (Burseraceae) is an economically and pharmacologically important slow growing, dioecious, balsamiferous woody, multipurpose shrub heading towards extinction. Commonly known as “Guggul” due to the presence of steroidal compound guggulsterone in the oleo-gum resin, it has been used in treating various ailments and disorders since ancient times (2000 B.C.). Evaluation and confirmation of hypolipidemic effects of guggul based on Ayurvedic text in 1960s provided a new insight into its pharmacological applications. Two bioactive isomers of guggulsterone, E and Z, are responsible for lipid- and cholesterol-lowering activities. Recently, it has been shown to have anti-cancerous activity also. It is found in the dry regions of Indian subcontinent, namely India, Pakistan and Bangladesh. Ruthless and unscientific harvesting of oleo-gum resin from the wild, by local populations, for economic benefits with negligible conservation efforts has made this species endangered and has led to its inclusion in Red Data Book of IUCN. Although this plant has many excellent traits, adequate attention has not been focused on its conservation and improvement. Conventional propagation methods i.e., seeds, cuttings and air layering are in place but have many limitations. Therefore, application of modern biotechnological tools needs to be standardized for harnessing maximum benefits from this pharmaceutically important plant. An efficient regeneration system needs to be in place for improvement of this genus through genetic transformation and production of useful metabolites in cell cultures. Studies are in progress for micropropagation through shoot multiplication and somatic embryogenesis, as well as for secondary metabolite (guggulsterone) production in callus cultures and bioreactors. No selected germplasm is available for C. wightii since it is a wild plant. Breeding programs have not yet been started due to lack of systematic cultivation and conservation programs. Moreover, little information has been gathered regarding the genetic variability in this species using RAPD and ISSR markers. No details are available about genetic makeup and QTL linkage maps. Investigations are in progress to search sex linked markers in this dioecious species. Research is also in progress to decipher the molecular mechanisms underlying various pharmacological actions of guggul. Since the approval of use of guggul as a food supplement by United States Food and Drug Administration in 1994, an exponential increase in research publications on various aspects of research on guggul have been published. Present communication summarizes the problems, progress made and suggests some future directions of research for this important endangered medicinal plant.  相似文献   
94.
Poly(1,4-phenylene sulfide) (PPS) exhibits good dimensional stability and flame retardant characteristics but its commercial development as fibers is highly limited due to lesser dyeing and finishing characteristics. Hence in the present study, we focused on the anionic and cationic modifications of PPS to enhance its dyeing ability towards disperse, cationic, and anionic dyes. Novel sulfonation and chloromethylation-quaternization of PPS fiber were carried out to achieve an industrially viable dyeing process methodology. The chemically modified PPS fiber is dyed with disperse, cationic, and anionic dyes, and the dyeing adsorption efficiency is quantitatively studied using a dye-o-meter equipped with UV-visible absorption spectroscope. The ideal parameters for dye adsorption were determined as a function of dyeing time, material-toliquor ratio, dyeing temperature, carrier concentration, sulfonation, and chloromethylation. The fastness properties of the dyed fabrics were also studied. Overall, with a maximum dye uptake of 99 % and 90 % achieved for sulfonated PPS and quaternized PPS respectively, the optimized conditions can be readily scaled-up to the commercial dyeing of PPS fiber with disperse, anionic, and cationic dyes.  相似文献   
95.
Manganese (Mn) deficiency has become a serious nutritional problem for wheat grown in alkaline coarse textured soil. The study aimed to investigate post-anthesis Mn partitioning in different wheat species. Cultivars of bread wheat (‘PBW509’, ‘DBW17’, ‘PBW550’ and ‘PBW636’); durum wheat (‘PDW291’) and triticale (‘TL2908’) were grown in 6.5 L pots with two treatments of Mn (0 and 50 mg Mn kg?1 soil) in screen house and harvested at anthesis, 18- days post-anthesis, and maturity to record Mn uptake. Durum cv. ‘PDW291’ retained highest proportion of Mn in its vegetative parts under Mn deficiency resulting into lowest partitioning to the grain and had the lowest grain yield. All bread wheat cv. facilitated superior Mn partitioning to the grain, lesser retention in vegetative organs and higher Mn utilization efficiency, than triticale and durum wheat species. Cultivars producing higher yield on Mn deficit soils are viable alternative to foliar application of Mn.  相似文献   
96.
Many maternally inherited and incurable neuromyopathies are caused by mutations in mitochondrial (mt) transfer RNA (tRNA) genes. Kinetoplastid protozoa, including Leishmania, have evolved specialized systems for importing nucleus-encoded tRNAs into mitochondria. We found that the Leishmania RNA import complex (RIC) could enter human cells by a caveolin-1-dependent pathway, where it induced import of endogenous cytosolic tRNAs, including tRNA(Lys), and restored mitochondrial function in a cybrid harboring a mutant mt tRNA(Lys) (MT-TK) gene. The use of protein complexes to modulate mitochondrial function may help in the management of such genetic disorders.  相似文献   
97.
Wool fabrics, without any surface treatment, can undergo undesirable and irreversible structural changes of wool fiber during washing under heat and mechanical agitation, leading to high shrinkage of wool garments. The traditional method based on polyamide resin can prevent felting and/or shrinkage of wool textiles, but adversely affect the surface hydrophobicity. In the present study, a treatment solution was developed based on TriSilanolIsooctyl POSS® and 3- mercaptopropyl trimethoxysilane, which created wool surface with increased hydrophobicity and highly resistant to shrinkage or felting, as measured after 3×5A wash cycles (equivalent to 24 domestic washes). After the treatment, the wool fabric appeared to be superhydrophobic with a water contact angle of above 150°, compared to the untreated fabric. The treatment has marginal effect on mechanical performance as observed in tensile properties. Scanning electron microscopic images revealed a coating of POSS® on the wool surface. The dyeing of untreated and treated fabrics appeared to be uniform to the naked eye, though spectrophotometric analysis indicated a difference in the extent of dyeing performance. This research showed that POSS®-based treatment is a potentially effective approach for developing shrink-resistant wool textiles with enhanced surface hydrophobicity, in contrast to traditional chlorine/polyamide resin treatment.  相似文献   
98.
The X-ray in the field of medical imaging is an important diagnostic tool, but it has been identified that there are potential radiation risks associated with the X-ray radiation scans. These risks have traditionally been guarded against using lead based shields. Lead has excellent radiation shielding properties, but it is also heavy and a potential health and environmental hazard due to its toxicity. Thus, there have been studies seeking to find an alternative that is as effective and yet counters the other drawbacks. In this paper, preliminary studies were conducted to assess the shielding effect of barium sulphate (BaSO4) and bismuth oxide (Bi2O3) on the coated fabric samples. X-ray transmission resulting from standard lead coated samples, uncoated fabric, BaSO4, and BaSO4/Bi2O3 coated fabrics was evaluated via measuring the penetration of primary radiation. Different properties such as mass per unit area, material thickness, and surface morphology were examined. All samples were irradiated by X-ray at 80 kVp to measure the amount of transmissions. The X-ray transmission level associated with BaSO4 ranged from 84.5 % to 70.5 %. However, this level was elevated to 55.6 % when BaSO4/Bi2O3 mixture was applied on the fabric. The theoretical attenuation coefficient values associated with different coating mixtures comprising different weight proportions of BaSO4, Bi2O3, and PVC were determined between 0 MeV and 105 MeV using XCOM code. The XCOM results implied that the X-ray attenuation coefficient among all prepared coatings should be the mixture comprising 13.3 wt% Bi2O3/20 wt% BaSO4/66.7 wt% PVC, which was in agreement with the experimental results obtained from X-ray transmission measurements.  相似文献   
99.
A tumor-like tissue mass of lateral-limbal site in the right eye of a 12-year-old Cob Pony mare was presented for surgical removal. The mass, covering the lateral limbus, bulbar conjunctiva and part of the cornea, was surgically removed, and the corneal defect repaired with a pedicle bulbar conjunctival graft. The mass was inflammatory in nature containing mononuclear cells. No recurrence or complication occurred at 6- and 12-month follow-up examination.  相似文献   
100.
This paper reports on model studies on energy dissipatorswhich were performed with a view towards developing a shorterand more efficient type of stilling basin for circular pipeoutlets at low Froude numbers. The stilling basin models weretested for two pipe outlet diameters. The outlet Froude numberfor testing ranged from 1.70 to 5.50. The studies reported inthis paper expand on the improvement suggested by Goel andVerma (1999). In all, 133 test runs were made on 19 newmodels. Various configurations of stilling basin models withdifferent sizes, shapes and locations of appurtenances andbasin lengths were tested. The use of a wedge-shaped splitterblock, an impact wall, and the use of wedge-shaped blocks asbaffle blocks resulted in efficient energy dissipation inshorter lengths of stilling basin. A non-dimensional numbertermed as scour index has been used to compare theperformances of various stilling basin models. It was foundthat the length of stilling basin could be reducedconsiderably without affecting the performance by choosing asuitable configuration of the stilling basin. Of theconfigurations tested, the stilling basin model M-24 with tworows of wedge-shaped baffle blocks in a basin length of sixtimes the diameter of pipe outlet (6d) performed better incomparison to USBR impact type VI stilling basin.  相似文献   
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