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101.
Immunohistochemical diagnosis of Neospora caninum in tissue sections 总被引:10,自引:0,他引:10
An avidin-biotin-peroxidase complex immunoperoxidase staining method was developed to detect Neospora caninum in formalin-fixed, paraffin-embedded tissue sections. Specific antiserum to N caninum was made in rabbits and used to probe tissues from dogs naturally and experimentally infected with N caninum. The test detected tachyzoites and bradyzoites of N caninum. A reaction was not observed to Toxoplasma gondii, Hammondia hammondi, Sarcocystis cruzi, S capricanis, S tenella, Besnoitia jellisoni, Caryospora bigenetica, Hepatazoon canis, Atoxoplasma sp, or the organism causing canine dermal coccidiosis. When antiserum made in rabbits to T gondii was used in the test, reaction to N caninum was not observed. 相似文献
102.
Two mixed-breed littermate dogs were fed mouse brains containing tissue cysts of the NC-beef isolate of Neospora caninum. Both dogs excreted N. caninum oocysts in their feces. Dog 1 which was given methylprednisolone acetate (MPA) prior to ingesting tissue cysts, excreted oocysts on days 5 to 10 inclusive and on day 17 after ingesting tissue cysts. Dog 1 had a serum antibody titer of 1:200 in the indirect fluorescent antibody test (IFAT) 35 days after it was fed tissue cysts. Dog 2, which was not treated with MPA, excreted oocysts on Day 6 and Day 9 after ingesting tissue cysts. Antibodies to N. caninum were not found in a 1:25 dilution of serum on any examination period for Dog 2 during the study. Neospora caninum was not found in the tissues of either dog by histological or immunohistochemical means following necropsy 42 days after being fed tissue cysts. The identity of the oocysts excreted in the feces of the dogs was confirmed by mouse inoculation studies. 相似文献
103.
Clark HR Goyder E Bissell P Blank L Walters SJ Peters J 《Public health nutrition》2008,11(10):1030-1036
OBJECTIVE: Parentss food choices and weight, but little is known about the social class distribution of parent self-reported child-feeding behaviours in two socio-economically contrasting areas. DESIGN: A cross-sectional survey using the Parental Feeding Style Questionnaire. Mean scores were calculated for five child-feeding behaviours: control over eating, emotional feeding, encouragement/prompting, instrumental feeding and restriction. Parents behaviours that might be used to directly influence children's food intake and weight. CONCLUSIONS: Child-feeding behaviours differ between areas within a single city and within a largely white population, and this distribution is related to socio-economic and educational factors. Experimental and longitudinal studies are needed to further investigate the potential role of child-feeding behaviours in childhood overweight and obesity. 相似文献
104.
105.
G.A. Hamilton A.D. Ruthven Elizabeth Findlay K. Hunter D.A. Lindsay 《Biological conservation》1981,21(4):315-326
Deaths of wild and domestic animals have been investigated over a seven-year period. A large number of animals have been poisoned by deliberate misuse of pesticides. These have included many protected species as well as domestic animals. Three pesticides, alphachloralose, mevinphos and strychnine, were found to be used in 94% of these cases. Misuse of pesticides was mainly seasonal and much of it was associated with the protection of young game birds and some arable crops. The difficulties of countering this illegal practice are discussed. 相似文献
106.
Problems have been encountered in transporting salmonid eggs and in rearing the eggs of some marine species owing, it is believed, to mechanical shock. Acting on the premise that survival might be improved by immersion of eggs in solutions of increased viscosity experiments were carried out using high molecular weight inert polymers. A 1% solution of methyl cellulose gave promising results. 相似文献
107.
Chase-Lansdale PL Moffitt RA Lohman BJ Cherlin AJ Coley RL Pittman LD Roff J Votruba-Drzal E 《Science (New York, N.Y.)》2003,299(5612):1548-1552
Results from a longitudinal study of 2402 low-income families during the recent unprecedented era of welfare reform suggest that mothers' transitions off welfare and into employment are not associated with negative outcomes for preschoolers (ages 2 to 4 years) or young adolescents (ages 10 to 14 years). Indeed, no significant associations with mothers' welfare and employment transitions were found for preschoolers, and the dominant pattern was also of few statistically significant associations for adolescents. The associations that did occur provided slight evidence that mothers' entry into the labor force was related to improvements in adolescents' mental health, whereas exits from employment were linked with teenagers' increased behavior problems. 相似文献
108.
109.
Lindsay G Ross Judith Sanchez Blanco Carlos Martínez-Palacios Ilie S Racotta & Mayra Toledo Cuevas 《Aquaculture Research》2007,38(9):909-917
Anaesthesia, sedation and transportation of the Atherinopsid, Menidia estor, were investigated using benzocaine, hypothermia and combinations of the two. The optimum dose rates of benzocaine for sedation of juvenile Chirostoma estor were 15 and 18 mg L−1. When hypothermia was used alone, stable sedation of C. estor was induced at 15 and 12°C, with no mortalities and full recovery after about 8 min. There was synergism when benzocaine and hypothermia were combined, with the optimal combination being at 15°C and 12 mg L−1 benzocaine. Successful transportation was conducted over 3.5 and 8.5 h using combined benzocaine and hypothermia. Aloe vera extract used in the transportation medium reduced scale loss. This work has, for the first time, defined a systematically derived system of safe, long distance, live transportation of this species and others of the genus Menidia. 相似文献
110.
Holm TM Habashi JP Doyle JJ Bedja D Chen Y van Erp C Lindsay ME Kim D Schoenhoff F Cohn RD Loeys BL Thomas CJ Patnaik S Marugan JJ Judge DP Dietz HC 《Science (New York, N.Y.)》2011,332(6027):358-361
Transforming growth factor-β (TGFβ) signaling drives aneurysm progression in multiple disorders, including Marfan syndrome (MFS), and therapies that inhibit this signaling cascade are in clinical trials. TGFβ can stimulate multiple intracellular signaling pathways, but it is unclear which of these pathways drives aortic disease and, when inhibited, which result in disease amelioration. Here we show that extracellular signal-regulated kinase (ERK) 1 and 2 and Smad2 are activated in a mouse model of MFS, and both are inhibited by therapies directed against TGFβ. Whereas selective inhibition of ERK1/2 activation ameliorated aortic growth, Smad4 deficiency exacerbated aortic disease and caused premature death in MFS mice. Smad4-deficient MFS mice uniquely showed activation of Jun N-terminal kinase-1 (JNK1), and a JNK antagonist ameliorated aortic growth in MFS mice that lacked or retained full Smad4 expression. Thus, noncanonical (Smad-independent) TGFβ signaling is a prominent driver of aortic disease in MFS mice, and inhibition of the ERK1/2 or JNK1 pathways is a potential therapeutic strategy for the disease. 相似文献