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71.
Regucalcin (RGN) is a calcium‐regulating, anti‐apoptotic, antioxidative and antiproliferative multifunctional protein predominantly seen in liver and kidney. All these functions are very crucial during spermatogenesis and sperm maturation process until fertilization of the ovum. Although many studies have reported the wide distribution of regucalcin in the male reproductive tract of the rat, human and bovine, its presence in spermatozoa is yet to be demonstrated wherein calcium has a pivotal role in the transport, capacitation, acrosomal reaction and further fusion with ova. Here, we detected the expression of regucalcin mRNA and protein in buffalo spermatozoa using real‐time PCR and Western blot, respectively. The study detected two new regucalcin isoforms of 44 kDa and 48 kDa size along with the reported 34‐kDa, 28‐kDa and 24‐kDa isoforms, wherein the 34‐kDa isoform was found to be membrane associated in spermatozoa. Further, immunocytochemistry study localized the regucalcin protein in the acrosomal region of the caudal and ejaculated buffalo spermatozoa while it was detected in both cytoplasm and acrosomal region of testicular spermatozoa. This discovery of RGN in spermatozoa and localization in the acrosomal region will help to focus researchers to see its role in calcium‐related functions like capacitation, acrosomal reaction and membrane fusion. Overall, regucalcin may be a new fertility marker in buffalo and can be utilized for infertility treatments.  相似文献   
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Summary In two distinct areas of East Africa 28,238 and 16,303 non-teneral flies respectively were caught. Infected probosces containing mature trypanosome infections were macerated and inoculated into laboratory animals. Differences in the transmission of trypanosomes existed between different species of tsetse fly. The effect on transmission of trypanosome infection rate in the fly and species of host on which the flies fed is discussed. A method to estimate trypanosome challenge is proposed.
Sumario Se atraparon 28,238 y 16,303 moscas tsetse respectivamente en dos areas didtintas de Africa Oriental. Se maceraron proboscis infectadas con tripanosomas maduros y fueron inoculadas en animales de laboratorio. Existieron diferencias en la trasmisión de tripanosomas entre las distintas especies de moscas tsetse. Se discute el efecto obtenido sobre la transmisión por el grado de infección con tripanosomas en la mosca y en hospederos de los cuales la mosca se alimenta.

Résumé On a capturé dans deux régions différentes de l'Afrique de l'Est respectivement 28.238 et 16.303 mouches ayant pris au moins un repas. Les trompes infestées, contenant des trypanosomes métacycliques, ont été macérées et inoculées á des animaux de laboratoire. Il existait des différences dans la transmission de trypanosomes entre différentes espéces de glossines. L'effet sur la transmission du taux de l'infection á trypanosomes chez la mouche et l'espèce d'h?te sur lequel les mouches s'étaient nourries est discuté. On propose une méthode pour estimer l'intensité des inoculations trypanosomiennes.
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Thirty spring wheat varieties were evaluated and classified into eight different groups on the basis of their grain yield performance and phosphorus (P) uptake using Metroglyph analysis. Significant variability was observed for grain and biomass yield, plant height, P content in grain and straw, total P uptake and phosphorus harvest index and P use efficiency traits. Varieties WH 711 and PBW 343 exhibited high grain yield as well as high P uptake (HGY-HP). WH 283 and UP 2425 with high index score of 19 and 16 respectively, constituted the high grain yield-medium P uptake (HGYMP) group. Both these varieties, though had similar grain yield of 5348 kg/ha, but WH 283 (12.64 kg/ha) utilized much lower P as compared to UP 2425 (16.94 kg/ha). Moreover, WH 283 (81.64) also showed higher values for phosphorus harvest index (PHI) than UP 2425 (67.88%). P uptake of WH 283 was comparable with that of Raj 3765 (10.78 kg/ha) and grouped into high grain yield and low P uptake (HGY-LP) group. The grain yield performance of these two varieties with a relatively low P uptake is reflected in their high index score for P use efficiency thus, earmarking them for low P regimes. Variety HW 2006, despite low grain yields of 4665 kg/ha had high index score of 16 due to its higher value for Phosphorus Biological (PBER) and Economic Yield (PEER) Efficiency Ratio as it has effected least (7.18 kg/ha) P mobilization. In addition high P translocation in the grain was also observed for this variety. Inter-mating of genotypes like HW 2006, UP 2338 and HW 2016 with those belonging to HGY-HP (PBW 343 and WH 711) and HGY-LP (Raj 3765 and WH 283) would be an ideal strategy to develop the cultivars for efficient phosphorus use.  相似文献   
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Summary Summer squash (Cucurbita pepo) cultivars, three from each of the six cultivar groups, were grown under field and greenhouse conditions at Fort Pierce, Florida, U.S.A. in the presence of sweetpotato whiteflies (Bemisia tabaci) and observed for severity of leaf silvering. All cultivars were affected by leaf silvering, but some had less severe symptoms than others. The cocozelle group was the least susceptible to silvering. There appeared to be an association between geographic origin of cultivars and their susceptibility to silvering.Florida Agricultural Experiment Station Journal Series no. R-02844.  相似文献   
78.
Cucurbita pepo (pumpkin, squash,gourd) is an economically important species that is susceptible to the cucurbit powdery mildew fungus, Podosphaera xanthii(syn. Sphaerotheca fuliginea). ‘True French’, an open-pollinated cultivar of the Zucchini Group of C. pepo, was crossed with an unnamed powdery-mildew resistant straight neck-type accession, the resistance of which was apparently derived from an interspecific cross with a resistant wild species of Cucurbita,and resistant plants were selected in the F2 generation. This was followed by six cycles of backcross-pedigree selection for resistance, and resulted in the development of an accession true-breeding for resistance to powdery mildew and nearly isogenic to ‘True French’. The resistant and susceptible near-isogenics were crossed and seeds of the filial and backcross generations were produced. Plants of the parental accessions and their progenies were grown together in a controlled-environment chamber, exposed to the pathogenic fungus, and scored as resistant, partially resistant, or susceptible 27–33 days after sowing. The results indicated that resistance is conferred by a single incompletely dominant gene, designated Pm-0. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
79.
Summary The mode of inheritance for resistance to zucchini yellow mosaic virus (ZYMV) in Cucurbita moschata was determined from F1, F2, and backcross progenies of the cross between the susceptible cultivar Waltham Butternut from the U.S.A. and a resistant inbred line of the Menina cultivar from Portugal. Resistance to ZYMV in Menina was conferred by a single dominant gene designated Zym.  相似文献   
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Summary Fordhook Zucchini, a squash (Cucurbita pepo) cultivar having intensely colored fruits conditioned by genotype D/D L-1/L-1 L-1/L-2, was crossed with Beirut, a squash cultivar having lightly colored fruits. Beirut was also crossed with Vegetable Spaghetti, a cultivar having lightly colored fruits conditioned by genotype d/d l-1/l-1 l-2/l-2, and with tester stocks of genotypes d/d L-1/L-1 l-2/l-2 and d/d l-1/l-1 L-2/L-2. The results indicated that Beirut, like Vegetable Spaghetti, possesses genotype d/d l-1/l-1 l-2/l-2. However, no F2- or backcross-generation segregates possessing the Light type 1 phenotype, conditioned by recombinant genotype d/d L-1/-l-2/l-2 and heretofore observed when Fordhook Zucchini was crossed with Vegetable Spaghetti, were recovered when Fordhook Zucchini was crossed with Beirut. The results of crossing Beirut with Vegetable Spaghetti and with the tester stocks indicated that both Beirut and Fordhook Zucchini carry a recessive gene, designated pl, which results in Plain light fruit coloration in plants of d/d L-1/- l-2/l-2 genotype. Beirut possesses genotype d/d l-1/l-1 l-2/l-2 pl/pl, Fordhook Zucchini D/D L-1/L-1 L-2/L-2 pl/pl, and Vegetable Spaghetti d/d l-1/l-1 l-2/l-2 Pl/Pl. Both the dominant D allele and the dominant L-2 allele are epistatic to gene pl.Contribution No. 3443-E from the Agricultural Research Organization, Bet Dagan, Israel  相似文献   
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