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991.
992.
HuQing GaoShumin LiFenglan 《中国林学(英文版)》2004,6(4):13-16
In order to investigate flower development and female abortion during sex differentiation ofXanthoceras sorbifolia,anatomical observations and comparative study on differential proteins were carried out in different developmental stages of two types of flowers of this species. It was found that the selective abortion happened in male flower before the formation of megasporocyte. Special proteins related to the female abortion were found through 2-dimensional electrophoretic analysis. Protein Al(14.2 kD)only existed in florescence of male flower, while B1 (13.7 kD) and B2 (18.2 kD) disappeared in that stage of male flower. They were all considered to be relative to pistil abortion ofXanthoceras sorbifolia. 相似文献
993.
青霉素在香石竹组织培养中的作用 总被引:14,自引:0,他引:14
青霉素10-80万单位/1对香石竹(Dianthus caryophyllus L.)愈伤组织芽的分化有促进作用,对愈伤组织苗的生长有抑制作用。在80万单位/1浓度时芽生长出现异常现象。青霉素对杆插苗的生长有抑制作用。随着苗的生长、浓度的提高,对发生根的抑制增强,对芽的抑制减弱,以至消失。在香石竹培养中对消除玻璃化苗、叶色彩化有明显效果。 相似文献
994.
995.
Diabetes mellitus in a population of 180,000 insured dogs: incidence, survival, and breed distribution 总被引:1,自引:0,他引:1
Fall T Hamlin HH Hedhammar A Kämpe O Egenvall A 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(6):1209-1216
BACKGROUND: Canine diabetes mellitus (DM) is a common endocrinopathy with an unclear etiology. For a better understanding of the underlying mechanisms, there is a need for comprehensive epidemiologic studies. Earlier studies have shown that the risk of disease is higher in certain dog breeds. HYPOTHESIS: Incidence, age of onset, survival and sex proportion of DM vary by breed. ANIMALS: Data from a cohort of 182,087 insured dogs aged 5-12 years accounting for 652,898 dog-years at risk were studied retrospectively. METHODS: Incidence rates by sex, breed, and geography were calculated with exact denominators. Age-specific incidence and survival after 1st DM claim were computed with Cox's regression and Kaplan-Meier survival function. Multivariable survival analysis was performed for the outcome diagnosis of DM with age, sex, and geography tested as fixed effects, previous endocrine or pancreatic diseases tested as time-dependent covariates, and breed tested as a random effect. RESULTS: The mean age at 1st insurance claim for the 860 DM dogs (72% females) was 8.6 years. The incidence of DM was 13 cases per 10,000 dog-years at risk. Australian Terriers, Samoyeds, Swedish Elkhounds, and Swedish Lapphunds were found to have the highest incidence. The proportion of females with DM varied significantly among breeds. Swedish Elkhounds, Beagles, Norwegian Elkhounds, and Border Collies that developed DM were almost exclusively females. The multivariable model showed that breed, previous hyperadrenocorticism, and female sex were risk factors for developing DM. Median survival time was 57 days after 1st claim. Excluding the 223 dogs that died within 1 day, the median survival time was 2 years after 1st claim of DM. CONCLUSION: The significant breed-specific sex and age differences shown in this study indicate that genetic variation could make breeds more or less susceptible to different types of DM. 相似文献
996.
Kusuhara H Hohdatsu T Seta T Nemoto K Motokawa K Gemma T Watanabe R Huang C Arai S Koyama H 《Veterinary microbiology》2007,120(3-4):217-225
Feline immunodeficiency virus (FIV) vaccine, Fel-O-Vax FIV, was released for sale in the US in 2002. The antibodies of vaccinated cats interfere with serological assays by currently available FIV diagnostic kits. In this study, we investigated whether it is possible to distinguish serologically cats vaccinated with Fel-O-Vax FIV from cats experimentally or naturally infected with FIV. A total of 153 sera taken from 97 cats were used as serum samples. Enzyme linked immunosorbent assay (ELISA) was performed using whole FIV antigen and formalin treated whole FIV antigen, recombinant-gag (r-gag) antigen, and transmembrane (TM) peptide. Statistical analysis was performed using ELISA optical density (O.D.) values obtained with each antigen as variables. Except for the ELISA O.D. values obtained with r-gag antigen, a significant difference in ELISA O.D. values was observed between the vaccinated and the infected groups. However, it was not possible to distinguish both groups unequivocally. Using discriminant analysis, it was possible to distinguish the two groups with an accuracy of 97.1% with two discriminating variables (ELISA O.D. values obtained with formalin treated whole FIV antigen, and TM peptide), 97.8% with three discriminating variables (ELISA O.D. values obtained with whole FIV antigen, formalin treated whole FIV antigen, and TM peptide). Therefore, it was considered possible to distinguish cats vaccinated with Fel-O-Vax FIV from FIV-infected cats by ELISA using two types of antigens including formalin treated whole FIV antigen and TM peptide, or three types of antigens including formalin treated whole FIV antigen, TM peptide and whole FIV antigen. 相似文献
997.
长根金钱菌生物学特性研究 总被引:2,自引:0,他引:2
长根金钱菌(Oudemansiella radicata)菌丝生长的最适碳源是果糖,最适氮源是酵母粉,最适温度20-25℃,最适PH6.0-7.0,最适培养基含水量60%。子实体原基分化温度25-27℃,最适昼夜温差℃,空气相对湿度85%-90%时能正常形成原基。 相似文献
998.
González-Morán MG Guerra-Araiza C Campos MG Camacho-Arroyo I 《Domestic animal endocrinology》2008,35(4):371-379
Sex steroid hormone receptors play a central role in the regulation of reproduction in male chickens. In this work, we evaluated by histomorphometric methods and Western blot analysis changes in the number of the different cell populations and in the content of sex steroid hormone receptors in testes from immature (1.5-month-old), mature (12-month-old), and aged (48-month-old) chickens. The number of Sertoli cells, germ cells, and Leydig cells per area of testicular tissue markedly changed according to chicken age. The highest number of Sertoli and Leydig cells was found in testes of immature chickens, with a dramatic decrease in those of mature chickens; however, the number of germ cells was the highest in mature chickens in comparison with other ages. The content of androgen receptor diminished in testes of mature and aged animals in comparison with that of immature chickens. In contrast, the content of estrogen receptor alpha and progesterone receptor was higher in testes of mature animals than in other ages. Both progesterone receptor isoforms were expressed in a similar proportion in testes of immature and mature animals. Interestingly, progesterone receptor isoform A was the predominant isoform in aged animals. These results suggest that there are marked age-dependent changes in chicken testes histology and in sex steroid hormone receptors content that should contribute to sex steroid hormone actions, in this tissue throughout the lifespan of chickens. 相似文献
999.
Long AC Agler A Colitz CM Zhang J Hayek MG Failla ML Bomser JA 《Veterinary ophthalmology》2008,11(1):38-42
OBJECTIVE: The purpose of this study was to characterize the proliferation and differentiation of primary canine lens epithelial cells (LEC) under standard culture conditions. PROCEDURE: Canine LEC were isolated by mechanical dissection of the canine globe and enzymatic digestion of the lens capsule from fresh lenses. Isolated capsules and cell suspensions were seeded in laminin-coated culture flasks. Canine LEC proliferated and formed monolayers, which could be passaged and maintained for approximately 2 weeks. Cells were characterized morphologically and cell lysates examined for expression of protein markers of epithelial origin and differentiation. RESULTS: Canine LEC exhibit morphologic characteristics of epithelial cells when cultured on laminin/lysine coated flasks. Expression of epithelial cell marker, cytokeratin 5, was highest at passage 1 and diminished with increasing passage number. Expression of gamma-crystallin, a protein found only in differentiated lens fiber cells, increased at passage 6. A laminin/lysine-coated surface supported optimal proliferation of canine LEC. Both an initial seeding density of 1 x 10(5) cells/cm(2) and culture in Dulbecco's modified essential media (DMEM) supplemented with 10% FBS supported a doubling time of less than 48 h in canine LEC. CONCLUSION: This study demonstrates that primary canine LEC retain the characteristics of lens epithelial cells prior to passage 6 under the described culture conditions and represent a suitable in vitro model for investigating lens physiology and cataractogenesis. 相似文献
1000.
An epidemiological study with the objective to assess the prevalence of paramphistomosis in association with season, age,
sex and breed was carried out in naturally infected sheep over a period of two years from February 2005 to January 2007. Gastrointestinal
tract (GIT) and faecal examination were conducted monthly to monitor the seasonal occurrence of paramphistomosis. 793 sheep
were examined in the first year, out of which 7.06% were positive for Paramphistomum infection. In the second year, 740 animals were investigated and 7.7% were infected. The overall prevalence of paramphistomosis
was 7.3% with a mean of 56.50 ± 0.50 and 95% confidence interval (CI) (lower bound: 50.1469; upper bound: 62.8531). The prevalence
of paramphistomosis through GIT examination (P = 0.593) was 7.6% at 95% CI (lower bound: −19.1186; upper bound: 57.1186) and the prevalence through faecal examination (P = 0.884) was 7.2% at 95% CI (lower bound: 5.7345; upper bound: 69.2655). Generally, season and age were the factors found
to have a significant influence on the risk of paramphistomosis in sheep. The highest infection was found in the summer season
(P < 0.005); lower age groups (P < 0.005) in males and in migratory (Bhakarwal) breed (P ≥ 0.005). Winter, adult animals, females and local breed reported low infection. The present study will be of great significance
to understand the epidemiology of gastrointestinal helminthes of sheep initially in the resource poor communities of Himalayan
region and will definitely be helpful to devise appropriate control strategies for paramphistomosis. 相似文献