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1.
Two Vietnamese pot-bellied pigs (Sus scrofa) were euthanatized after they developed abdominal distension. Necropsy of both pigs revealed large myometrial neoplasms and cystic endometrial hyperplasia. Multiple discrete smaller myometrial neoplasms were also observed in one pig; however, distant metastases were not observed in either animal. The tumors were diagnosed as leiomyomas on the basis of histologic examination and immunohistochemistry. This is the first detailed report of uterine leiomyomas in swine, and it is suggested that this diagnosis may become more common as more aging pigs are examined.  相似文献   
2.
This study investigated the suitability of the non-destructive vibration-impulse excitation technique to assess the attack of preservative-treated wood in contact with the ground. Small stakes (10×5×100 mm3) of treated and untreated Scots pine sapwood were exposed to decay in laboratory-scale terrestrial ecosystems. Different soils were used to prove the influence of different types of wood destroying micro-organisms. Wood decay was monitored periodically for one year by determining mass losses and changes in dynamic modulus of elasticity. The results show a large variability in resistance against attacking fungi, depending on wood preservative and soil type. The non-destructive approach using the dynamic modulus of elasticity proved to be a good and sensitive tool for assessing the attack of stakes in laboratory soil testing.  相似文献   
3.
The objective of this study was to explore the possibility of producing wild buffalo embryos by interspecies somatic cell nuclear transfer (iSCNT) through handmade cloning using wild buffalo somatic cells and domestic buffalo (Bubalus bubalis) oocytes. Somatic cells derived from the ear skin of wild buffalo were found to express vimentin but not keratin and cytokeratin‐18, indicating that they were of fibroblast origin. The population doubling time of skin fibroblasts from wild buffalo was significantly (p < 0.05) higher, and the cell proliferation rate was significantly (p < 0.05) lower compared with that of skin fibroblasts from domestic buffalo. Neither the cleavage (92.6 ± 2.0% vs 92.8 ± 2.0%) nor the blastocyst rate (42.4 ± 2.4% vs 38.7 ± 2.8%) was significantly different between the intraspecies cloned embryos produced using skin fibroblasts from domestic buffalo and interspecies cloned embryos produced using skin fibroblasts from wild buffalo. However, the total cell number (TCN) was significantly (p < 0.05) lower (192.0 ± 25.6 vs 345.7 ± 42.2), and the apoptotic index was significantly (p < 0.05) higher (15.1 ± 3.1 vs 8.0 ± 1.4) for interspecies than that for intraspecies cloned embryos. Following vitrification in open‐pulled straws (OPS) and warming, although the cryosurvival rate of both types of cloned embryos, as indicated by their re‐expansion rate, was not significantly different (34.8 ± 1.5% vs 47.8 ± 7.8), the apoptotic index was significantly (p < 0.05) higher for vitrified–warmed interspecies than that for corresponding intraspecies cloned embryos (48.9 ± 7.2 vs 23.9 ± 2.8). The global level of H3K18ac was significantly (p < 0.05) lower in interspecies cloned embryos than that in intraspecies cloned embryos. The expression level of HDAC1, DNMT3a and CASPASE3 was significantly (p < 0.05) higher, that of P53 was significantly (p < 0.05) lower in interspecies than in intraspecies embryos, whereas that of DNMT1 was similar between the two types of embryos. In conclusion, these results demonstrate that wild buffalo embryos can be produced by iSCNT.  相似文献   
4.
Thunderstorms: an important mechanism in the transport of air pollutants   总被引:3,自引:0,他引:3  
Acid deposition and photochemical smog are urban air pollution problems, and they remain localized as long as the sulfur, nitrogen, and hydrocarbon pollutants are confined to the lower troposphere (below about 1-kilometer altitude) where they are short-lived. If, however, the contaminants are rapidly transported to the upper troposphere, then their atmospheric residence times grow and their range of influence expands dramatically. Although this vertical transport ameliorates some of the effects of acid rain by diluting atmospheric acids, it exacerbates global tropospheric ozone production by redistributing the necessary nitrogen catalysts. Results of recent computer simulations suggest that thunderstorms are one means of rapid vertical transport. To test this hypothesis, several research aircraft near a midwestern thunderstrom measured carbon monoxide, hydrocarbons, ozone, and reactive nitrogen compounds. Their concentrations were much greater in the outflow region of the storm, up to 11 kilometers in altitude, than in surrounding air. Trace gas measurements can thus be used to track the motion of air in and around a cloud. Thunderstorms may transform local air pollution problems into regional or global atmospheric chemistry problems.  相似文献   
5.
Because of its position to the west of Europe, much of the wet sulphur deposition in the west of the UK is background in the sense that it is not attributable to pollutants emitted within Europe less than four days previously. There are both natural and anthropogenic sources of this sulphur. An important natural source, especially during the summer, is dimethylsulphide (DMS) produced by marine phytoplankton. To identify the contribution of marine biogenic sulphur we have measured stable sulphur isotope ratios in precipitation. We show that biogenic sulphur is significant in summer but contributes little in winter and that around 5–10% of the annual background wet sulphur deposition is due to biogenic sources. During July and December 1993, airflow across the UK was predominantly westerly. The measured biogenic component of precipitation sulphate accounted for around 30 % of background sulphate in July but was negligible in December. Investigation of five day back-trajectories for the period indicated little opportunity for re-circulation of European emissions, suggesting that other (non-DMS) natural sources and non-European anthropogenic emissions were responsible for most of the background sulphur.  相似文献   
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7.
Information on the mating and dispersal behaviour of the rice stem borers Scirpophaga incertulas and Chilo suppressalis is necessary for the design of resistance management strategies for rice varieties genetically engineered with toxin genes from Bacillus thuringiensis (Bt). We investigated whether S. incertulas and C. suppressalis move from the site of adult eclosion before mating to determine the likelihood that random mating will occur between adults eclosing in fields of Bt rice and refuge fields of non-Bt rice. Observations were made under laboratory, screenhouse and field conditions. Almost all S. incertulas males and females flew out of sight after cuticle expansion and hardening, as did most C. suppressalis. Approximately 15% of C. suppressalis females called and mated within 3?m of the site of eclosion, and approximately 5% of C. suppressalis males mated within 5?m of the site of eclosion. These results suggest that random mating is likely to occur between S. incertulas eclosing in Bt rice fields and nearby refuge fields. Although a small proportion of C. suppressalis did not move far before mating, random mating of moths from Bt and nearby refuge fields is also likely to occur in this species if Bt-resistant moths are rare.  相似文献   
8.
A 3-year-old female American Cocker Spaniel with a chronic hemolytic disorder and hemolytic crises was found to have M-type phosphofructokinase deficiency. This inherited erythroenzymopathy and myopathy is commonly diagnosed in English Springer Spaniels, but the family study of this Cocker Spaniel, although supporting an autosomal recessive mode of inheritance, did not reveal any English Springer Spaniel ancestors. Molecular genetic studies did, however, identify the same mutation in this dog as we previously reported in the English Springer Spaniel breed, suggesting that this mutation originated prior to the separation of these 2 breeds.  相似文献   
9.
A 1.5-year-old captive female Dama wallaby (Macropus eugenii) died after a 3-month period of progressive weight loss, anorexia, bloat, and diarrhea. Histopathologic examination revealed numerous Entamoeba histolytica trophozoites within the gastric mucosa and, less frequently, gastric submucosa and submucosal vessels. Immunofluorescent antibody testing confirmed the identity of the trophozoites as E. histolytica. The trophozoites were associated with mild glandular epithelial necrosis, mucosal erosions, and lymphoplasmacytic inflammation. E. histolytica most commonly causes necrotizing and ulcerative colitis in humans and captive nonhuman primates, and it causes necrotizing and ulcerative gastritis in nonhuman primates with sacculated stomachs adapted for leaf fermentation. Rare cases of gastric amebiasis also have been been reported in captive macropods, which also have complex sacculated stomachs. To our knowledge, this is the first report confirming E. histolytica as the cause of gastric amebiasis in a wallaby. The zoonotic potential of this infection in macropods is uncertain.  相似文献   
10.
An 8-year-old cat, with a history of ataxia that progressed to tetraparesis over a 5-day period, was evaluated. A lesion was localized to the sixth cervical (C6) to second thoracic (T2) spinal cord segments based on physical and neurological examination findings. Blood work was unremarkable, as was survey radiography of the thoracic and abdominal cavities. Cerebrospinal fluid analysis showed moderate neutrophilic inflammation. A definitive diagnosis was not made until necropsy, at which time intravascular fibrocartilaginous embolization (FCE) of the cervical spinal cord was identified. This is only the third published report of FCE in the feline species and the first such case involving the cervical spinal cord.  相似文献   
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