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21.
The objective of the present study was to determine the factors that influenced growth performance of the goat kids of Black Bengal (BB), Saanen (SA), and their crossbred F1 (male Bengal × female Saanen [BBSA] and male Saanen × female Black Bengal [SABB]). Data for 674 kids were analyzed from 316 litters and 134 does. All kids were weekly measured on their characteristics (body weight, length, height at the withers, and chest girth) from birth to 11 weeks old. The kid’s breed and sex, litter size, and season of kidding influenced birth weight and other characteristics through the experiment. The SA and BBSA kids showed similar performance, which were higher than BB and SABB kids. Male kids had higher performance than female kids, and kids from a single litter showed the highest performance. Kids born during rainy season showed lower performance than those born in hot and cool seasons. In conclusion, the crossbred BBSA is superior to SABB or BB to raise in tropical climate Moreover, sex, litter size, and kidding season also affected growth performance during the preweaning period up to 11 weeks old.  相似文献   
22.
This study aimed to identify the genes associated with the development of the rumen epithelium by screening for candidate genes by digital differential display (DDD) in silico. Using DDD in NCBI's UniGene database, expressed sequence tag (EST)‐based gene expression profiles were analyzed in rumen, reticulum, omasum, abomasum and other tissues in cattle. One hundred and ten candidate genes with high expression in the rumen were derived from a library of all tissues. The expression levels of 11 genes in all candidate genes were analyzed in the rumen, reticulum, omasum and abomasum of nine Japanese Black male calves (5‐week‐old pre‐weaning: n = 3; 15‐week‐old weaned calves: n = 6). Among the 11 genes, only 3‐hydroxy‐3‐methylglutaryl‐CoA synthase 2 (HMGCS2), aldo‐keto reductase family 1, member C1‐like (AKR1C1), and fatty acid binding protein 3 (FABP3) showed significant changes in the levels of gene expression in the rumen between the pre‐ and post‐weaning of calves. These results indicate that DDD analysis in silico can be useful for screening candidate genes related to rumen development, and that the changes in expression levels of three genes in the rumen may have been caused by weaning, aging or both. © 2015 Japanese Society of Animal Science  相似文献   
23.
This study was intended to examine whether serum IGF-I concentration is appropriate for use as a physiological predictor for genetic improvement of meat production and meat quality traits in pigs. Heritabilities and genetic correlations were estimated for these traits. The Duroc breed used in this study was selected for seven generations for average daily BW gain (DG) from 30 to 105 kg of BW, loin-eye muscle area (EM), backfat thickness (BF), and intramuscular fat (IMF) content. Serum IGF-I concentration of boars and gilts at the fourth generation of selection and that of boars, gilts, and barrows from the fifth to seventh generations of selection were measured at 8 wk (IGFI-8W) for 832 animals and again at the time they reached 105 kg of BW (IGFI-105KG) for 834 animals. A multivariate REML procedure was used to estimate genetic parameters with a model incorporating generation of selection, sex, common environmental effect of litter, and individual additive genetic effects. Heritability estimates for IGFI-8W and IGFI-105KG were 0.23 +/- 0.02 and 0.26 +/- 0.03, respectively. The estimates of common environmental effect for IGFI-8W and IGFI-105KG were 0.20 +/- 0.02 and 0.03 +/- 0.01, respectively. Positive genetic correlations were estimated between IGFI-8W and DG (0.26 +/- 0.08), EM (0.22 +/- 0.10), and IMF (0.32 +/- 0.10). Moreover, the positive genetic correlation between IGFI-105KG and EM was 0.42 +/- 0.08. These results indicate that serum IGF-I concentration at an early stage of growth was effective for prediction of IMF, but it was not a reliable physiological predictor of genetic merit of meat production traits.  相似文献   
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Acetylated, propionylated, butyrylated, isobutyrylated, and hexanoylated woods were prepared at several temperatures. The reaction rate, dimensional stability, and changes in the ratios of specific gravity and dimensions in the tangential and radial directions were estimated. The reaction rate of propionylation was slow at temperatures under 90°C but increased with the temperature. The butyrylated, isobutyrylated, and hexanoylated woods showed little or no weight percent gain (WPG) and little or no antiswelling efficiency (ASE) below 110°C even for 24h, but they achieved significant WPG and ASE values at 140°C with a longer reaction time. The acetylated, propionylated, and butyrylated woods showed almost the same values for dimensional stabilization efficiency based on WPG (DSE). The specific gravity and dimensions ratios for acetylated, propionylated, and butyrylated woods compared to those of untreated wood increased with an increase in WPG.  相似文献   
26.
Variations in the composition of low boiling point (LBP) monoterpenes emitted from needle samples of 150 hinoki (Chamaecyparis obtuse) trees (30 strains, each with five clones) native to Shimane Prefecture, Japan, were investigated using a headspace technique. The assays revealed considerable proportional variations especially in the amount of sabinene, which ranged from 24% to 78% of the total LBP monoterpenes. The proportions of α-pinene, myrcene, and limonene negatively correlated with that of sabinene overall. In particular, the proportion of limonene showed clear negative correlation with that of sabinene (r = −0.98). Differences in the proportion of sabinene among five clones in each strain were less than 15% in 22 out of 30 strains, indicating that monoterpene composition is constitutively steady in most strains. In a few strains, however, considerable variation in the composition was observed among clones.  相似文献   
27.
Stomach tissues from 222 beagle dogs, which were used for toxicological studies, were examined histopathologically. Out of 190 dogs fed the same diet, 185 had gastric lesions, whereas all of 32 dogs fed another diet were free from them. The gastric lesions were noted as an accumulation of eosinophils, infiltration of inflammatory cells including lymphocytes, plasma cells and histiocytes in the gastric lamina propria, formation of foreign body type multinucleated giant cells, focal desquamation and papillary proliferation of mucosal epithelium. The lesions were confined to the superficial layer of the antral and pyloric mucosa, and neither desmoplasia nor clinical signs were seen. Multinucleated giant cells often contained amphophilic foreign bodies of varying appearance with inconsistent reaction for periodic acid-Schiff (PAS), but no definite causal agents were detected.  相似文献   
28.
Characteristics of signal transduction systems mediated by protein kinase-C (Ca2+/phospholipid-dependent protein kinase) and estradiol receptors in cow placenta and caruncle were conducted by evaluating protein kinase-C activity and estradiol receptor concentrations and by exploring substrate proteins for the enzyme. The enzyme activity was detected in cytosolic and total particulate fractions of both tissues. The activity levels in these fractions were comparable to those in other cow tissues such as liver and mammary gland. The enzyme activity was inhibited by palmitoylcarnitine, gossypol and adriamycin, known phospholipid-interacting inhibitors of the enzyme. Phosphorylation by the enzyme and subsequent autoradiography revealed that only 125K protein in placental cytosol and two low molecular weight proteins in caruncular cytosol were found to be substrates for protein kinase-C. Ca2+ acts as inhibitor of the phosphorylation of several phosphoproteins other than the substrates. Estradiol receptor concentrations in cytosolic and nuclear fractions were similar in both tissues, and the cytosolic concentrations were also comparable to those in pregnant uterus. However, the nuclear concentrations were extremely low when compared to those in the uterus. The signal transduction systems mediated by protein kinase-C and by estradiol receptors seem to be concertedly suppressed in cow placenta and caruncle.  相似文献   
29.
The Rio Grande do Sul state, in Southern Brazil, is one of the foci of human cystic echinococcosis (CE). The sheep strain (G1) of Echinococcus granulosus and Echinococcus ortleppi (also known as cattle strain G5) have been reported before to infect livestock. However, up to the present, no molecular data are available on isolates of the E. granulosus complex from humans and dogs. The present study analyzed hydatid cysts from 6 CE patients and adult worms from 12 dogs. Sequencing of the mitochondrial cox1 and 12S rRNA genes detected the E. granulosus G1 genotype from four human cases, the G3 genotype (or buffalo strain) from one human case and E. ortleppi from another human case, respectively. Ten of the twelve dogs were found infected with the G1 genotype, and one dog each harbored worms of the G3 genotype and E. ortleppi. Obvious morphological differences were recognized between the G1 and E. ortleppi adult worms from dogs in this region. The buffalo strain (G3) is for the first time reported from South America.  相似文献   
30.
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