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71.
Nineteen analogues were synthesized by modifying the tert-butylhydrazine moieties of N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methyl-2,3-dihydro-1,4-benzodioxine-6-carbohydrazide and N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methylchromane-6-carbohydrazide (chromafenozide), and the synthesized analogues were evaluated for their insecticidal activity against Spodoptera litura F. While all of the synthesized analogues had insecticidal activity inferior to those of the lead compounds, several of the analogues nonetheless showed high insecticidal activity. Chromafenozide has shown very high selectivity toward lepidopteran species.  相似文献   
72.
OBJECTIVES: To determine whether small intestinal ischemia and reperfusion affects intestinal intramucosal pH (pHi), arterial and portal venous blood gas values, and intestinal blood flow (IBF) and to investigate relationships between regional intestinal tissue oxygenation and systemic variables in dogs. ANIMALS: 15 healthy adult Beagles. PROCEDURE: Occlusion of superior mesenteric artery (SMA) for 0, 30, or 60 minutes, followed by reperfusion for 180 minutes, was performed; IBF, pHi, arterial and portal venous blood gas values, arterial pressure, and heart rate were measured at various time points; and intestinal mucosal injury was histologically graded. RESULTS: Occlusion of the SMA induced significant decreases in pHi and IBF. After the release of the occlusion, IBF returned rapidly to baseline values, but improvement in pHi was slow. Arterial and portal venous blood gas analyses were less sensitive than tonometric measurements of pHi, and there was no correlation between results of blood gas analyses and tonometric measurements. Histologic score for intestinal mucosal injury increased significantly, depending on duration of ischemia, and there was a correlation between tonometric results and the histologic score. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that it is difficult to accurately evaluate local oxygenation disorders by monitoring at the systemic level, whereas clinically pHi is the only reliable indicator of inadequate regional intestinal tissue oxygenation in dogs.  相似文献   
73.
Histopathological features of livers and blood chemical values in cows with abomasal displacement were investigated. Liver biopsy samples were collected during redressment operations in 92 cows with abomasal displacement, and the samples were stained with haematoxylin and eosin or periodic acid Schiff (PAS). Blood was collected for chemical tests. Livers were histopathologically divided into the following four types: normal histology cases (21%), fatty degeneration cases (36%), cloudy swelling cases (19%) and fatty degeneration cases with cloudy swelling (24%). The number of PAS-positive samples was significantly higher in the normal histology group and significantly lower in the severe fatty degeneration group and severe cloudy swelling group. Cows with fatty degeneration had significantly higher levels of serum 3-hydroxybutyric acid, non-esterified fatty acid and aspartate aminotransferase than did those with cloudy swelling or normal histology. The results indicate that the morbid conditions of cows with abomasal displacement can be classified into four types.  相似文献   
74.
Polymorphisms and the antiviral property of porcine Mx1 protein   总被引:9,自引:0,他引:9  
We determined the cDNA sequences of the type I interferon-inducible proteins, pig Mx1 from PK(15) and LLC-PK1 cells, and compared the antiviral activities of both Mx proteins, including Mx1 polymorphisms against vesicular stomatitis virus (VSV). Mx1 cDNA derived from PK(15) cells had an 11 bp-deletion in the 3' end of the coding region, and was estimated to encode 8 amino acid substitutions and a 23 amino acid extension compared to that from LLC-PK1 cells. VSV replication was inhibited in the 3T3 cells expressing Mx1 mRNA after the cDNA was transfected. However, the efficiency of this inhibition was not different between the cells expressing Mx1 mRNA from both PK and LLC. These results indicate that pig Mx1 protein confers resistance to VSV.  相似文献   
75.
An intradural tumor in the upper cervical region was found in a dog with quadriparesis and chronic respiratory acidosis. Surgical removal of the tumor in the atlas and intraoperative radiotherapy were attempted. The tumor was histologically diagnosed as a neural glioma. A preoperative acid-base disturbance was dramatically improved after surgery. The clinical changes appeared in this case suggest that compression of the spinal cord at this region may cause paralysis of the respiratory muscles and secondarily result in chronic respiratory acidosis following the respiratory insufficiency.  相似文献   
76.
This study was designed to clarify the characteristics of changes in plasma concentrations of reproductive hormones in heifers from birth to puberty. Weekly or daily hormonal changes were observed in 39 heifers. Daily changes in the concentration of follicle-stimulating hormone (FSH) demonstrated a consistent cycle of hormone changes over a 7- to 8-day period in heifers from approximately 10 days to 9 months old. Weekly changes in reproductive hormones showed that there were three brief periods in heifers between birth and puberty in which dramatic changes occur. The first period was the first week after birth, during which a reciprocal relationship between steroid hormones and gonadotropins was observed. At birth, the concentrations of steroid hormones were higher than those at any other age. These hormone levels rapidly decreased within the first week after birth. Gonadotropin levels, however, increased from birth to 1 week of age. The second period of major change was at approximately 4 weeks of age when there was an increase in the concentrations of luteinizing hormone (LH), estradiol-17beta, testosterone, and immunoreactive inhibin. The third period was the last 5 weeks before the first ovulation, when there was an increase in the concentrations of estradiol-17beta followed by an increase in (LH). These results suggest that regular hormone changes start from 10 days after birth and that the periods from birth to 4 weeks of age and the last 5 weeks before the first ovulation in heifers are important to the development of reproductive functions before puberty.  相似文献   
77.
The present study was designed to evaluate the effects of tumour necrosis factor-alpha (TNF-alpha) on lactating bovine mammary functions such as milk protein secretion and the integrity of the milk-blood barrier. The effect on the induction of the systemic inflammatory response was also examined using concentrations of serum haptoglobin (Hp), a major inflammatory acute-phase protein, as an index. One hundred micrograms per mammary gland of recombinant bovine (rBo) TNF-alpha or placebo saline was individually infused into a rear mammary gland of each of four lactating cows, and milk and blood samples were collected before and 4, 8, 24, 32, 48, 96 and 168 h after infusion. In the rBoTNF-alpha-infused gland, increases of somatic cell counts were observed at 4-48 h. Although concentrations of total milk protein were not changed, compositions of milk proteins varied following rBoTNF-alpha infusion. Concentrations of caseins, alpha-lactalbumin and beta-lactoglobulin were significantly decreased at 4 and 8 h. Lactoferrin concentrations were significantly increased at 4 h. Significant infiltrations of serum albumin, immunoglobulin G1 (IgG1) and IgG2 were observed at 4 and 8 h. Elevations of the serum concentration of Hp were detected at 8-32 h, but were very small in comparison with those reported in inflammatory diseases. Changes in rectal temperature and white blood cell counts were not significant. These results show that single rBoTNF-alpha infusion into the lactating mammary gland suppresses the lactogenic function of the gland and influences the function of the milk-blood barrier, with little effect on the generalized inflammatory response.  相似文献   
78.
A new chemolytic therapy with amino acid preparation was tried for use on struvite renal stones in two dogs, which were admitted to Azabu University Veterinary Teaching Hospital. No other special diet, for the purpose of dissolving the stones, was fed during the treatment. Dissolution of the stones began at week 1, and no stone was detected on radiography at week 4 in both cases. The amino acid preparation thereafter has been administered every 2-3 days to prevent formation of the stones. After 6 months from treatment, complete dissolution was confirmed, and no relapse has been observed. Therefore, it is concluded that chemolytic therapy with amino acid preparation might be useful for the treatment of nephrolithiasis with struvite renal stones in dogs.  相似文献   
79.
To investigate the relation between the canine pigmented epidermal nevus (PEN) and cutaneous papillomavirus, we cloned and sequenced the L1 gene of papillomavirus from the canine pigmented epidermal nevus (PEN). Amplification of DNA sample with the L1 consensus primers yielded an expected fragment of approximately 450-bp. The nucleotide sequences of the fragment showed about 64% of sequence similarity to the L1 region of human papillomavirus isolate CP6108 and less than 57% sequence similarity to those of canine oral papillomavirus (COPV). In situ hybridization determined the presence of papillomavirus DNA mainly in the upper stratum granulosum of skin in this case. The results indicated that the canine cutaneous papillomavirus from the PEN lesion was genetically close to human papillomavirus rather than COPV.  相似文献   
80.
ABSTRACT The presence of mulberry dwarf (MD) phytoplasmas in organs of the inoculative vector insects Hishimonoides sellatiformis and Hishimonus sellatus was determined by means of electron microscopy (EM) and polymerase chain reaction (PCR) assays. Many MD phytoplasmas were detected in genital organs as well as in the intestines, salivary glands, brains, fat bodies, and thoracic ganglia of Hishimonoides sellatiformis, but only in the intestine and salivary glands of Hishimonus sellatus. Many phytoplasmas with characteristic morphology were observed via EM in ovaries, seminal receptacles, and testes, and they were further identified by PCR assays with group I-specific primers. In addition, the organisms were detected by direct or nested PCR assays in eggs (head pigmentation stage of embryos) laid on mulberry shoots by inoculative leafhoppers and in the newly hatched nymphs from these eggs. These findings indicate that transovarial transmission of MD phytoplasmas occurs in Hishimonoides sellatiformis.  相似文献   
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