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141.
CASE HISTORY: A 400-cow dairy unit in the Waikato suffered a severe outbreak of facial eczema (FE) despite consistent zinc supplementation and significantly elevated serum zinc concentrations.

CLINICAL FINDINGS: FE prevention had begun in mid-January 2006, via zinc sulphate supplementation in the water. Photosensitisation was reported on 06 April, contemporaneous with a marked increase in the number of Pithomyces chartarum spores in pasture samples. Within 10 days of this first clinical case, 100 affected cows had been dried off, eight of which subsequently died or were culled. Blood samples were collected from ten affected cows; all had serum zinc concentrations >17 µmol/L, and eight had gamma-glutamyl transferase (GGT) activities >200 U/ml, indicating that the photosensitisation was secondary to liver damage, i.e. probably FE. Further investigation identified that this herd had been receiving excess copper supplementation; 4/6 culled cows had liver copper concentrations within or above the marginal range for copper toxicity.

DIAGNOSIS: Severe FE despite zinc supplementation that increased serum zinc concentrations above recommended levels

CLINICAL RELEVANCE: As zinc supplementation significantly reduces apparent copper status, copper supplementation is often used to counteract this. Previous excess copper intake may reduce the efficacy of zinc in preventing FE, thus copper intake should be assessed prior to the start of zinc supplementation.  相似文献   
142.
CASE HISTORY: A 3-month-old female Angus calf was found dead, and two adult Friesian dairy cows died soon after developing nervous signs.

PATHOLOGICAL FINDINGS: Grossly, bilateral and mostly symmetrical areas of haemorrhage were evident that mainly involved areas of grey matter in the brainstem from the level of the caudal colliculi to the thalamus and, in one, the internal capsule and caudate nucleus. In the occipital and caudal parietal cortex, there was extensive oedema of white matter. Histologically, in addition to haemorrhage, there was protein-rich oedema around arterioles and venules in the cerebrum, hippocampus, internal capsule, thalamus, midbrain, dorsal medulla, and central cerebellar and cerebellar folial white matter. The calf's brain had bilateral and symmetrical oedema and necrosis affecting several brainstem nuclei and the occipital grey matter overlying areas of oedema of the corona radiata.

DIAGNOSIS: Although the cause was not established, the perivascular lesions resembled those produced in calves by the intravenous administration of epsilon toxin.

CLINICAL RELEVANCE: It is possible that epsilon toxin-induced enterotoxaemia occurs naturally in cattle, and where bilateral haemorrhage is recognised in the brains of cattle, small intestinal contents should be collected for analysis of epsilon toxin.  相似文献   
143.
144.
When buffalo embryonic stem (ES) cell–like cells that expressed surface markers SSEA‐4, TRA‐1‐60, TRA‐1‐81, CD9 and CD90 and intracellular markers OCT4, SOX2 and FOXD3, as shown by immunofluorescence, and that expressed REX‐1 and NUCLEOSTEMIN as confirmed by RT‐PCR, were subjected to suspension culture in hanging drops in absence of LIF and buffalo foetal fibroblast feeder layer support, they differentiated to form three‐dimensional embryoid bodies (EBs). Of 231 EBs examined on Day 3 of suspension culture, 141 (61.3 ± 3.09%) were of compact type, whereas 90 (38.4 ± 3.12%) were of cystic type. The cells obtained from EBs were found to express NF‐68 and NESTIN (ectodermal lineage), BMP‐4 and α‐skeletal actin (mesodermal lineage), and α‐fetoprotein, GATA‐4 and HNF‐4 (endodermal lineage). When these EBs were cultured on gelatin‐coated dishes, they spontaneously differentiated to several cell types such as epithelial‐ and neuron‐like cells. When EBs were cultured in the presence of 1 or 2% DMSO or 10?8 m or 10?7 m retinoic acid for 25 days, ES cells could be directed to form muscle cell–like cells, the identity of which was confirmed by expression of α‐actinin by immunofluorescence and of MYF‐5, MYOD and MYOGENIN genes by RT‐PCR. MYOD was first detected on Day 10 in both treatment groups and on Day 15 in controls, whereas MYOGENIN was first detected on Day 10, Day 15 and Day 25 in the presence of retinoic acid, in the presence of DMSO and in controls, respectively. The present study demonstrates the ability of buffalo ES cell–like cells to undergo directed differentiation to cells of skeletal myogenic lineage.  相似文献   
145.
AIM: To determine the relationship between the concentrations of Cu in plasma and serum in red deer, and to compare this relationship with those previously reported in cattle and sheep.

METHODS: Paired serum and heparinised plasma samples from 114 red deer from 10 herds (n=6-20 per herd) were analysed for concentrations of Cu. Samples were collected either at slaughter (n=84; eight herds) or by jugular venepuncture (n=30; two herds). Thirty-nine of the samples taken at slaughter were from adult hinds from four herds, while other samples were taken from 10–14-month-old males, except for one herd (10 samples) where an equal number of 8–9-month-old males and females were sampled. The effect of age, gender and herd on the relationship between concentrations of Cu in plasma and serum was assessed using univariate ANOVA. The individual results for concentrations of Cu in serum were compared with those in plasma, using limits-of-agreement plotting.

RESULTS: The mean concentration of Cu in plasma was not significantly different from that of serum (0.048; 95% CI=-0.14 to 0.24 µmol/L). There was no effect of age, sex or herd on this relationship.

CONCLUSIONS: In deer, there was no significant difference between concentrations of Cu in plasma and serum regardless of age, sex or herd of origin.

CLINICAL RELEVANCE: In contrast to the situation in cattle and sheep, the concentration of Cu in serum can be used interchangeably with that in plasma for the estimation of concentration of Cu in blood of red deer.  相似文献   
146.
Abstract

CASE HISTORY: One 4.5-month-old male Border Collie cross presented with aggression and seizures in October 2006. A 16-month-old, female, spayed Border Collie cross presented with hypersalivation and a dropped jaw and rapidly became stuporous in September 2007. The dogs were littermates and developed acute neurological signs 5 and 27 days, respectively, after vaccination with different modified live vaccines containing canine distemper virus.

HISTOPATHOLOGICAL FINDINGS: Sections of brain in both dogs showed evidence of encephalitis mainly centred on the grey matter of brainstem nuclei, where there was extensive and intense parenchymal and perivascular infiltration of histiocytes and lymphocytes. Intra-nuclear and intra-cytoplasmic inclusions typical of distemper were plentiful and there was abundant labelling for canine distemper virus using immunohistochemistry.

DIAGNOSIS: Post-vaccinal canine distemper.

CLINCIAL RELEVANCE: Post-vaccinal canine distemper has mainly been attributed to virulent vaccine virus, but it may also occur in dogs whose immunologic nature makes them susceptible to disease induced by a modified-live vaccine virus that is safe and protective for most dogs.  相似文献   
147.
The transplantation phase of narcissus micropropagation was studied using bulbils from bulbing shoots sub-cultured to hormone-free bulbing medium. Transplantation success was enhanced by the incorporation of activated charcoal in the medium, culturing the shoots at a constant 20°C and subjecting bulbils to a period of cold storage at 5°C to overcome dormancy prior to planting out. These measures gave overall figures for transplantation success in a large-scale evaluation experiment of 47.8-81.2% depending on cultivar. Greatest success was achieved using bulbils weighing more than 0.2 g. However, the overall proportion of such bulbils was only 0.19 to 0.20. Early leaf senescence, which limits bulbil growth in culture, appeared to be linked with initial bulbing shoot weight. The beneficial effects on transplantation of using full-strength mineral salts over halfstrength salts and of using one particular clone of cv. St. Keverne, were probably mediated via effects on final bulbil weight. Elevated concentrations of sucrose in the bulbing medium gave no benefit even though final bulbil weight was increased. High sucrose levels gave earlier shoot senescence and increased dormancy. Culture of bulbils in darkness did not effect final bulbil weight but was extremely detrimental to transplantation success. Most unsuccessfully transplanted bulbils showed a foliar growth phase suggesting a premature re-entry into dormancy. With few exceptions, bulbils judged to have been successfully transplanted grew on without problem in their second year.  相似文献   
148.
苎麻生物脱胶复合菌群的构建   总被引:1,自引:0,他引:1  
分别从沤麻池、苎麻脱胶厂污泥、老麻园土和腐烂麻堆等生境收集自然菌群,采用室内温水沤麻的方法检测它们的原始脱胶能力,结果表明:这些自然菌群的脱胶能力较弱,使苎麻分纤分别需要12 d、18 d、14 d和10 d,脱胶后的纤维强度极低,最高只有2.83 cN/dtex,失去了工业利用价值.将不同来源的菌群等比例混后用于脱胶试验,其分纤周期为8d,分纤时纤维强为2.58 cN/dtex.以苎麻为唯一碳源和能源对复合菌群进行长期驯化,分别在驯化至69 d、89 d、182 d和407 d发现其分纤周期缩短到了5d、4d、3d和2.2 d,而且随着分纤周期的缩短,纤维强度也逐渐提高.复合菌群驯化407d后,分纤周期稳定在50h左右,分纤状况良好,纤维强度达到了5.52 cN/dtex.  相似文献   
149.
The accumulation of skatole in boars to concentrations resulting in carcass taint has been associated with elevated concentrations of steroid hormones in plasma. Studying boar taint in vivo has been challenging because steroid hormones are highly variable between individual boars. However, a peak in steroid hormones occurs between 2 and 4 wk postpartum; therefore, skatole production was investigated in the prepubescent pig. Plasma concentrations of estrone sulphate, dehydroepiandrosterone sulphate, and testosterone peaked between 2 and 4 wk postpartum in intact male pigs, whereas plasma concentrations of these steroid hormones remained low or undetectable in gilts and barrows. However, plasma skatole concentration peaked in all 3 groups of animals between 2 and 3 wk postweaning. The effects of weaning time, intestinal cell turnover, and diet on tissue skatole concentrations were then investigated. Intact male piglets were weaned at 14, 21, 28, or 35 d of age. Plasma skatole concentrations were measured weekly for a period of 63 d and peaked at 17 +/- 1, 14 +/- 1, 13 +/- 1, and 10 +/- 2 d postweaning, respectively. Intestinal cell turnover, as evaluated by villous height:crypt depth ratio, was not correlated with skatole concentrations in cecal contents, suggesting that cellular debris did not constitute a gross source of tryptophan for hindgut fermentation. The inclusion of 10% chicory inulin to piglet diets suppressed the postweaning increase in plasma skatole. Cecal skatole concentrations were also 3.3-fold lower in inulin-supplemented piglets compared with controls. The rise in plasma skatole in the prepubescent intact male pig was not associated with increased steroidogenesis but is likely due to the postweaning adaptation of the intestinal flora to an abrupt dietary change.  相似文献   
150.
In the horse, breeding induces a transient endometrial inflammation. A subset of mares are unable to resolve this inflammation, and they are considered susceptible to persistent mating‐induced endometritis PMIE Select seminal plasma proteins cysteine‐rich secretory protein‐3 (CRISP‐3) and lactoferrin have been shown to affect the innate immune response to sperm in vitro. The objective of this study was to determine whether the addition of CRISP‐3 and lactoferrin at the time of insemination had an effect on the mRNA expression of endometrial cytokines in susceptible mares after breeding. Six mares classified as susceptible to PMIE were inseminated during four consecutive oestrous cycles with treatments in randomized order of: 1 mg/ml CRISP‐3, 150 μg/ml lactoferrin, seminal plasma (positive control) or lactated Ringer's solution (LRS; negative control) to a total volume of 10 ml combined with 1 × 109 spermatozoa pooled from two stallions. Six hours after treatment, an endometrial biopsy was obtained for qPCR analysis of selected genes associated with inflammation (pro‐inflammatory cytokines interleukin (IL)‐1β, IL‐8, tumour necrosis factor (TNF)‐α, interferon (INF)‐γ, anti‐inflammatory cytokines IL‐1RN and IL‐10, and inflammatory‐modulating cytokine IL‐6). Seminal plasma treatment increased the mRNA expression of IL‐1β (p = .019) and IL‐8 (p = .0068), while suppressing the mRNA expression of TNF (p = .0013). Lactoferrin also suppressed the mRNA expression of TNF (p = .0013). In conclusion, exogenous lactoferrin may be considered as one modulator of the complex series of events resulting in the poorly regulated pro‐inflammatory response seen in susceptible mares.  相似文献   
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