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101.
102.
1. Frequency of Campylobacter detection was monitored in three flocks of turkeys. The effect of week of production was evaluated for hens in flocks 1 and 2, and the effect of week, gender and litter (fresh or used) was assessed for flock 3. 2. Gastrointestinal tracts, poult box liners, drinkers and faecal droppings were sampled. Conventional microbiological procedures were used to isolate and identify the presence of Campylobacter. Campylobacter latex agglutination tests were used for confirmation. 3. Peak colonisation occurred at approximately 3 weeks of production. Frequency of Campylobacter isolation from bird sources paralleled isolation from waterers. Frequency of detection from birds placed on used litter was lower than detection from birds placed on fresh litter (2% vs 58%). Gender did not affect frequency of detection. 4. Minimising peak colonisation at 3 weeks and managing litter are opportunities to reduce the occurrence of this organism in turkeys.  相似文献   
103.
In a field study, potassium (K) applied as muriate of potash (MOP) significantly reduced methane (CH4) emission from a flooded alluvial soil planted to rice. Cumulative emission was highest in control plots (125.34 kg CH4 ha−1), while the lowest emission was recorded in field plots receiving 30 kg K ha−1 (63.81 kg CH4 ha−1), with a 49% reduction in CH4 emission. Potassium application prevented a drop in the redox potential and reduced the contents of active reducing substances and Fe2+ content in the rhizosphere soil. Potassium amendment also inhibited methanogenic bacteria and stimulated methanotrophic bacterial population. Results suggest that, apart form producing higher plant biomass (both above- and underground) and grain yield, K amendment can effectively reduce CH4 emission from flooded soil and could be developed into an effective mitigation option, especially in K-deficient soils.  相似文献   
104.
Goat fleas of the order Siphonaptera were collected from the body surfaces of naturally infected polyarthritic goat kids with septicaemia. These fleas and the infected kids were positive for Mycoplasma mycoides subsp. mycoides (large colony type) identified by cultural, morphological, biochemical and growth inhibition tests. Blood from the infected fleas contained 1 × 102−1 × 105 viable subsp. mycoides ml−1. Experimental transmission of the disease to other kids was established by placing 120 infected fleas on each kid's body surfaces. All experimentally infected kids developed characteristic clinical signs and showed leucopenia with neutropenia, an increased amount of fibrinogen and mortality with lesions of suppurative polyarthritis associated with septicaemia. The organisms were also recovered in high numbers from heart blood, body fluids, and infected organs and joints. The results suggested that fleas of the order Siphonaptera acted as vectors for the transmission of the spontaneous disease in kids.  相似文献   
105.
106.
The time required for occurrence of estrogen-induced uterine tubal (oviductal) ciliogenesis and for differentiation of secretory cells was studied, utilizing electron microscopy procedures. Sixteen cycling gilts were ovariectomized; 3 to 4 months later, 12 principal gilts were each given subcutaneous injections of 17 beta-estradiol in 0.5 ml of corn oil at the rate of 200 mug/day, and 4 control gilts were given injections of corn oil only at the rate of 0.5 ml/day. Two principals each were killed on days 1, 2, 3, 4, 5, and 7 after start of treatment. The epithelial heights were low and completely atrophied 3 to 4 months after ovariectomy. Uterine tubal cilia were absent in all the control gilts. Cytologic changes were not seen in the atrophied epithelium of ovariectomized gilts 1 day after estradiol treatment, but definite proliferative elements consisting of an extensive fibrillar meshwork encrusted with granules (60 to 80 nm) were observed in close association with the nuclear envelope and in the apical cytoplasm after 2 days of estradiol treatment. By day 3, enlarged electron-opaque granules referred to as condensation forms, undergoing various stages of depletion, were closely associated with radially arranged procentrioles. These associations have been referred to as generative complexes. The presence of many generative complexes indicates that maximal production of basal bodies can be expected after 3 days of treatment with estradiol. The depletion of the condensation forms produced hollow spheres with thin walls as the procentrioles grew in length and assembled their microtubules. Enlarged mature-appearing basal bodies were abundant in the cytoplasm after 3 days of estradiol treatment. These bodies aligned themselves linearly along the luminal surface of the cell. Small ciliary buds were then formed above the cell surface, and ciliary filamentogenesis occurred in the bud. Motile cilia were observed on day 3, but cilia numbers increased markedly between day 4 and days 5 and 7. Procentrioles were generated from the diplosomal centriole after 2 days of estradiol treatment. These observations have provided evidence for both ancentriolar and centriolar basal body replication in the ciliated cells of uterine tube of the gilt. Maximal secretory cell differentiation occurred after 3 days of estradiol treatment. Hypertrophy of cytoplasmic organelles was evident on day 3, but the number of secretory granules and amount of rough endoplasmic reticulum increased markedly on days 5 and 7. Close association of secretory granules, Golgi apparatus, and endoplasmic reticulum was evident after estadiol treatment. These data indicate that both ciliated and secretory cells are sensitive to estrogen.  相似文献   
107.
108.
Tissue from the infundibulum region of the uterine tube (oviduct) of guinea pigs, cattle, sheep, and swine was examined by electron microscopy. In all specimens, cilia and ciliary rootlets were present in variable numbers in the ciliated cells during both the follicular and the luteal phases of the estrous cycle. True degeneration of cilia was not evident during luteal phase or pregnancy. The ciliary rootlets in ruminant and nonruminant species had structural similarities to those described in people and rhesus monkeys. These organelles measured approximately 1 mum long in most species studied, but in the cow, the rootlets, extending downward into the cytoplasm from the proximal end of the basal body, reached a length of 2 mum. The rootlets had a cross-striation of thick and thin bands, the period measuring 40 to 60 nm. Mitochondria were closely associated with the rootlets. The rootlets usually formed a small angle to the axis of the cilium. These organelles probably function as anchoring or stabilizing structures for the motile cilia. Results indicated that the rootlets are more widely distributed in mammalian uterine tube cilia than previously postulated. Polyribosomes, microfilaments, microtubules, and electron-opaque fibrous granules were frequently seen in the cytoplasm of the ciliated cells. The presence of fibrous granules in close association with the basal bodies indicate that these granules have a role in the development of cilia and rootlets. Cilia and precursor fibrous granules were also seen in porcine fetal uterine tube epithelial cells.  相似文献   
109.
Elucidation, through molecular analyses, of bacterial afflictions in commercially important aquaculture‐reared shrimps is pivotal for the prevention and/or control of disease outbreaks. In this study, we examined the phylogenetic relatedness and compared the possible immune‐related functional roles of both translationally controlled tumour protein (TCTP) and ferritin genes with previous studies. Both TCTP and ferritin genes were substantially upregulated in the Indian white prawn, Fenneropenaeus indicus (H. Milne Edwards), post‐larvae following bath challenge with the virulent strain of bacteria, Vibrio harveyi D3. Full‐length cloning of these genes by rapid amplification of complementary DNA ends ‐polymerase chain reaction (RACE‐PCR) yielded 727‐base pair (bp)‐long TCTP and 1212‐bp‐long ferritin gene sequences. Their open reading frames (ORFs) were 507 and 510 bp, respectively. The TCTP‐ORF coded for 168 amino acids with three substitutions at positions 37, 141, 155, and the ferritin ORF coded for 170 amino acids with no species‐specific substitutions. Phylogenetic analysis suggested the closest relatedness of both TCTP and ferritin from F. indicus to Chinese white prawn, Fenneropenaeus chinensis (Osbeck). In addition to reporting the full‐length sequences of these immune‐relevant genes, this study highlighted their conserved natures, which perhaps make them important defence‐related proteins in the innate immune system of F. indicus.  相似文献   
110.
Shoots regenerated adventitiously on epicotyl segments from in vitro seedlings of Emblica officinalis var. ‘Kanchan’. Epicotyls derived from 2-week-old aseptic seedlings were most responsive and produced a maximum number of 303 shoots per explant in Murashige and Skoog (1962) medium (MS) augmented with 8.8 μM N6-benzyladenine (BA) + 1.425 μM indole-3-acetic acid (IAA). Shoots readily elongated in MS lacking growth regulators and rooted in half-salt-strength MS (1/2 MS) supplemented with indole-3-butyric acid (IBA) or α-naphthalene acetic acid (NAA). The highest rooting response was recorded in 1/2 MS containing 14.7 μM IBA. Plantlets were acclimatized inside the green house and 80% of the plantlets survived on transfer to garden soil.  相似文献   
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