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71.
Ganges River dolphins (Platanista gangetica spp. gangetica) are air-breathing, warm-blooded mammals endemic to the Ganges and Karnaphuli rivers of the Indian subcontinent. Nevertheless, very little basic histomorphological research has been conducted on this endangered species. Therefore, this study aimed to describe the morphological features of different organs of P. gangetica. Despite becoming aquatic animals, they showed similarities with terrestrial mammals, such as the pair of lungs and an apical bronchus in the respiratory system, which are pretty standard in ruminants and pigs. However, unlike the terrestrial animal, the tracheobronchial tree was stiffer due to circularly arranged anastomosing plates of the hyaline cartilaginous ring in the trachea, cartilaginous plates in the bronchiole, and thick alveolar septa. The digestive system showed a three-chambered mechanical and glandular stomach similar to the artiodactyles. However, the intestine showed smaller caecum like the monogastric mammal. The urogenital system showed lobulated kidneys, a urinary bladder, a fibroelastic penis with sigmoid flexure, and a long urethral process similar to some terrestrial ruminants. Considering the aquatic environment, all those modifications, unlike terrestrial mammals, are necessary for their adaptation. Thus, this research will broadly help our clinicians and conservationist to take further steps toward disease diagnosis and monitoring of marine health of this endangered species.  相似文献   
72.
Oral feeding of male rats with the ethanolic leaf extract of Colebrookia oppositifolia at dose levels of 100 and 200 mg/kg for 8-10 weeks did not cause body weight loss, while the weights of testes and epididymides were significantly decreased. Seminal vesicles and ventral prostate showed a significant reduction at the higher dose only. Treated animals showed a notable depression of spermatogenesis. Following 100 and 200 mg/kg extract feeding, the preleptotene spermatocytes were decreased by 46.5 and 39.8%, the secondary spermatocytes by 13.4 and 12.7%, the step-19 spermatids by 36.6 and 35.2%, and the mature Leydig cells by 31.2 and 39.5%, respectively. At both dose levels, the seminiferous tubule diameter, Leydig cells nuclear area and cytoplasmic area, as well as the cross-sectional surface area of Sertoli cells, were significantly reduced (P<0.001) when compared to controls. Reduced sperm count and motility resulted in 100% negative fertility at 200 mg/kg dose level. A significant fall in the total protein and sialic acid content and acid phosphatase enzyme activity of the testes, epididymides, seminal vesicle and ventral prostate, as well as in the glycogen content of testes, was also observed at both dose levels in comparison with controls.  相似文献   
73.
Madhuca longifolia (Koenig) J. F. Macbride is native to India. Seeds contain 20–50% oil (Mahua oil) and the seed cake is used as manure. Mahua oil is used by rural communities for protection against storage pests. Almost all parts of this tree have medicinal properties. Four explorations and collection missions was conducted during July–October 2007 in Tamil Nadu and the Union Territory of Puducherry. This resulted in the collection of 55 accessions. Characterisation and analysis of 7 seed characters were done. The existence of enormous variability in seed length, thickness and 100 seed weight indicates scope for utilization of these accessions for selection of promising material for extraction of oil. Oil content of kernels has been evaluated. Kernel oil ranged from 44.43 to 61.50%. Three accessions IC556617 with 61.50, IC556632 with 60.80 and IC556632 with 60.55% of kernel oil are superior to the rest. Further collections in the site of these oil rich accessions are promising for more productive Madhuca longifolia genetic resources.  相似文献   
74.
Summary A survey was undertaken between March and September 1992 to assess the prevalence of fenbendazole resistance in sheep nematodes in 32 traditionally managed rural flocks and 22 intensively managed flocks on 3 farms. Fenbendazole, a commonly used anthelmintic was used at the recommended dose of 5 mg/kg body weight. Efficacy was determined on the basis of percentage reduction in strongyle faecal egg counts (FECR%) and larval cultures before and between 7 and 10 days after treatment. None of the traditionally managed rural flocks showed resistance and all had greater than 99% reduction in faecal egg counts after treatment.Of the 22 intensively managed flocks, however, 15 had slight fenbendazole resistance (between 60 and 90% reduction in egg counts) and 4 had severe resistance (less than 60% reduction).
Prevalencia De La Resistencia A Fenbendazole En Nematodos Ovinos En El Noroeste De India
Resumen Se llevó a cabo un estudio entre marzo y septiembre de 1992, para determinar la prevalencia de resistencia a fenbendazole de nemátodos ovinos en 32 rebaños con un manejo tradicional y 22 con un manejo intensivo en 3 fincas. El fenbendazole, un antihelmíntico comunmente usado, se dosificó a la dosis recomendada de 5 mg/kg de peso vivo. La eficacia fue determinada sobre la base del porcentaje de reducción en el conteo de huevos de estróngilus y los cultivos de larvas antes y entre 7 y 10 días después del tratamiento. Ninguno de los apriscos manejados tradicionalmente mostraron resistencia y todos tuvieron más del 99% de reducción en el conteo de huevos después del tratamiento.De los rebaños manejados intensivamente, 15 tuvieron una ligera resistencia al fenbendazole (entre 60 y 90% de reducción en el conteo de huevos) y 4 tuvieron resistencia marcada (menos de 60% de reducción).

Prevalence De La Resistance Au Fenbendazole De Nematodes Chez Des Ovins Du Nord-Ouest De L'Inde
esumé Une enquête a été entreprise de mars à septembre 1992 pour évaluer la prévalence de la résistance au fenbendazole de nématodes dans 32 troupeaux de moutons conduits en élevage traditionnel et 22 en élevage intensif appartement à 3 fermes. Le fenbendazole, anthelminthique communément utilisé, a été administré à la dose recommandée de 5 mg/kg de poids vif. Son efficacité a été déterminée à partir de la réduction du pourcentage du nombre d'oeufs de strongles dans les fèces et à partir de cultures de larves avant et entres le 7e et 10e jours après le traitement. Aucun des troupeaux en élevage traditionnel n'a montré de résistance au médicament et tous ont présenté une réduction de 99 p.100 du nombre d'oeufs dans les féces après le traitement. Une légère résistance au produit (entre 60 et 90 p.100 de réduction du nombre d'oeufs) a cependant été démontrée dans 15 des 22 troupeaux en élevage intensif et une résistance grave (réduction de moins de 60 p.100) dans 4 autres.
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75.
Despite low per-animal productivity of ruminants in developing countries, Johne's disease has not been investigated in buffaloes, which are primarily found in these countries. This is due to lack of expertise, diagnostic kits and priority to production diseases like Johne's disease. Presence of pathogenic Mycobacterium avium subspecies paratuberculosis (Map) was investigated by screening of target tissues (mesenteric lymph nodes and large intestine) by culture and IS 900 PCR, in 50 sacrificed buffaloes. Indigenous ELISA kit originally developed for goats and sheep was standardized in buffaloes and used to estimate sero-presence of Map in 167 serum samples representing population of buffaloes in Agra region of North India. In culture, 48.0% buffaloes were positive from 50 tissues each from mesenteric lymph nodes (34.0%) and large intestine (36.0%). IS 900 PCR was standardized using specific primers (150 C and 921) and 229 bp-amplified product was characteristic for Map. Of the 25 mesenteric lymph nodes, 40.0% were positive in IS 900 PCR. Genomic DNA from Map cultures was successfully amplified from all the 24 isolates (100.0%). Map was further genotyped as 'Bison type' using IS 1311 PCR-REA. Culture of tissues showed high presence of Map in target tissues, despite high culling rate in buffalos in view of high demand of buffalo meat. Specific tissue-PCR provided rapid confirmation of Map infection in sacrificed buffaloes. In tissue-PCR, all the cultures were positive as compared to 40.0% detected directly from tissues. ELISA kit using indigenous protoplasmic antigen was highly sensitive as compared to commercial antigen in detecting Map infection therefore, could be used as 'Herd Screening Test' in buffaloes against Johne's disease. This pilot study first time reports a highly pathogenic 'Bison-type' genotype of M. avium subspecies paratuberculosis from the riverine buffaloes (Bubalus bubalis) of Agra region in North India.  相似文献   
76.
Enhanced crop competition could aid in the management of annual sowthistle (Sonchus oleraceus L.), a dominant weed of Australian cropping systems. A two‐year pot study was conducted to evaluate the effect of wheat (Triticum aestivum L.) planting densities (0, 82, and 164 wheat plants/m2) on growth and seed production of glyphosate‐resistant (GR) and glyphosate‐susceptible (GS) biotypes of annual sowthistle. Without competition, both biotypes produced a similar number of leaves and biomass, but the GS biotype produced 80% more seeds (46,050 per plant) than the GR biotype. In competition with 164 wheat plants/m2, the number of leaves in the GR and GS biotypes was reduced by 62 and 61%, respectively, in comparison with the no‐competition treatment, and similarly, weed biomass was reduced by 78 and 77%, respectively. Compared to no‐competition treatment, the seed production of GR and GS biotypes was reduced by 33 and 69%, respectively, when grown with 82 wheat plants/m2, but increasing wheat density from 82 to 164 plants/m2 reduced the number of seeds only in the GS biotype (81%). Both biotypes produced greater than 6,000 seeds per plant when grown in competition with 164 plants/m2, suggesting that increased crop density should be integrated with other weed management strategies for efficient control of annual sowthistle.  相似文献   
77.
Rice–wheat cropping system to which graded levels of NPK fertilizers had been applied for 20 years were compared for yield trends, and changes in response function, soil organic-C and available N, P, K and S status. This study of system in which only chemical fertilizers had been used over a long period enabled long-term yield declines of rice and wheat at different levels and combinations of NPK fertilizers to be evaluated. The highest rate of yield decline in both rice and wheat was found when 120 kg ha−1 N was applied alone. The lowest rate of decline was observed when all three nutrients (N, P and K) were applied, at 40, 35 and 33 kg ha−1 for N, P and K, respectively, followed by 120, 35 and 33 kg ha−1 (currently recommended levels). The yield response of rice and wheat to N fertilizer declined over the 20 years, with a higher rate of decline in wheat. In contrast, the response to applied P and K increased with time in both crops, with a higher response rate in wheat. With continuous application of N and P fertilizers, there was a marginal change in available N and K in the soil over time, but an approximately 3-fold increase in available P and an approximately 2-fold increase in available S were obtained by regular dressing of P fertilizer (SSP: 7 % P, 12 % S) over 20 years. The results revealed that balanced, high doses of NPK fertilizers are required to maintain soil fertility and raise grain yields.  相似文献   
78.
79.
Recombinant fatty acid binding protein of Fasciola gigantica was expressed in Escherichia coli and purified by nickel chelating affinity chromatography. The recombinant protein along with native fatty acid binding protein (FABP) isolated from the parasite were evaluated for their potential in the diagnosis of F. gigantica infection in sheep, cattle and buffaloes, both by ELISA and western blotting. Results of this study indicate that there is no humoral immune response generated against this protein in the experimental infection of these ruminants with F. gigantica, thereby limiting the usefulness of this antigen in the early diagnosis of fasciolosis in these animals. Also, the paper discusses the probable reasons for the failure of this protein in detecting humoral response in these animals by ELISA and immunoblotting.  相似文献   
80.
The equitable distribution of canal water is imperative to ensure social justice as well as crop productivity. In north-west India and Pakistan, water from the tertiary canal (watercourse) is distributed to the farmers through a rotational system of irrigation. In this system the duration of supply to each farmer is in proportion to his holding in the outlet (watercourse) command, without considering the seepage loss. The rate of seepage loss increases with increase in length of watercourse from head to tail. Thus, the farmers in the lower reaches get much less water per unit area than the farmers in the upper reaches. The farmers must be compensated for the seepage loss. Therefore, a model was developed to ensure equitable distribution of water to the farmers located on a watercourse in proportion to their land holdings giving due compensation for the seepage loss. The model is based on the assumption that soil throughout the length of flow is homogeneous and loss through evaporation is negligible. The model developed ensures an equitable distribution of water to the farmers according to their land holdings. A comparison of existing and revised time allocation reveals that the farmers located in the upper reaches were getting more time (up to 12.2 min per unit area), while the farmers located in the lower reaches have been getting less time (up to 28.1 min per unit area). The existing allocation of time of 0.75 h per unit area to all the farmers according to the old rules was revised to 0.546–1.219 h per unit area from head to tail. The conclusions drawn suggest that the strategy developed here should be adopted elsewhere in the existing system of irrigation for equitable distribution of canal water. Received: 21 December 1999  相似文献   
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