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11.
In a series of field experiments in Ohio involving 193 parturient cows of the Holstein and Guernsey breeds, the prophylactic efficacy of selenium and vitamin E was tested under field conditions. Herds initially were chosen because of a chronic problem with retained placenta which could not be related to a known etiological factor. Each herd was divided into three groups. Group A received an injection of 50 mg of sodium selenite 40 days prepartum and 680 units of alpha tocopherol acetate followed by the same treatment 20 days prepartum. Group B received a single injection of 50 mg of sodium selenite 20 days prepartum, and 680 IU of vitamin E. Group C served as the control. Incidence of retained placenta was reduced from a mean of 51.2% in control cows to 8.8% for animals injected with selenium and vitamin E. No differences in efficacy were between Group A and B, and it appears that the single 20 day prepartum injection of 50 mg of sodium selenite and 680 IU of alpha tocopherol acetate is an effective prophylactic for prevention of retained placenta.  相似文献   
12.
The activities of certain drug metabolizing enzymes have been measured in liver and kidney slice preparations from domesticated birds. Aminopyrine demethylase activity was significantly lower in liver slices from the duck (Aylesbury X Pekin, Khaki-Campbell) than from the rat (Wistar), and in the Aylesbury X Pekin duck lower than in the turkey (Triple 6 FLX), chicken (Brown Leghorn, Rhode Island Red X Light Sussex) and goose (Emden X Doulouse). The microsomal cytochrome P-450 was lower in duck liver (Aylesbury X Pekin) than in rat liver, and the aniline hydroxylase and aminopyrine demethylase activities in a 10,000 g supernatant fraction of liver were lower in duck preparations (Aylesbury X Pekin, Khaki-Campbell) than rat preparations. These observations suggest that the duck is likely to be susceptible to drugs which are metabolized by the cytochrome P-450 containing mono-oxygenases. UDP-Glucuronyl transferase activity was not detectable in liver and kidney slices from two mature geese. This observation was not the outcome of a deficiency of UDP-glucuronic acid, rapid breakdown of glucuronide by beta-glucuronidase or the presence of a substance inhibitory to UDP-glucuronyl transferase. Liver slices from geese, ducks (Aylesbury X Pekin) and chickens contained low UDP-glucuronyl transferase and high sulphate conjugation enzyme activities, whereas the reverse was found in Khaki-Campbell ducks. The activities of UDP-glucuronyl transferase and the sulphate conjugation enzymes were both relatively high in liver slices from the turkey and rat. The kidney contained lower enzyme activities than the liver except in the duck (Aylesbury X Pekin), in which low activities of aminopyrine demethylase and UDP-glucuronyl transferase were present in slices of both organs. In liver slices from chickens and geese the activities of aminopyrine demethylase and the sulphate conjugation enzymes were similar in mature and immature birds, and the activity of UDP-glucuronyl transferase was considerably higher in chicks and goslings than in mature birds of the same species. In the chick the activities of aminopyrine demethylase, UDP-glucuronyl transferase and the sulphate conjugation enzymes were higher in the duodenum than the remainder of the alimentary tract. The activities of these enzymes in pieces of duodenum were as high as those in slices of liver. The inclusion of sulphate in the incubation medium produced a significant increase in the synthesis of p-nitrophenyl sulphate in liver slices and not kidney slices except those from the duck. The kidney slices seemed to produce sufficient sulphate for the reaction of the sulphate conjugation enzymes to proceed at the maximum rate, but the liver slices did not do so.  相似文献   
13.
Microelectrode recording in the thalamus of pigeons subjected to tilt and sinusoidal rotational stimuli around the vertical, longitudinal and transversal axes revealed vestibularly driven units in two thalamic nuclei, the nucleus posteroventralis and the nucleus principalis precommissuralis. Many of these units responded in a complex manner suggesting that inputs from contralateral and ipsilateral cupulae and maculae converged on them. A few units received additional visual or proprioceptive information. The homology relationship with a mammalian vestibular thalamic nucleus is discussed briefly.  相似文献   
14.
Androgen-induced gene activation in the rat prostate   总被引:1,自引:0,他引:1  
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15.
A significant number of offspring from brother-sister matings of NIH-Okamoto-Aoki spontaneously hypertensive rats (SHRs) were found to be normotensive at 20 weeks of age. Over 20% of the animals that were hypertensive at this age had mild-to-moderate unilateral hydronephrosis at the time of sacrifice. In over 90% of the rats that did not develop hypertension spontaneously, ligation of one ureter raised blood pressure above 150 mm Hg within 2 weeks. In those rats made hypertensive by obstructing one ureter and in those that developed hypertension with accompanying naturally occurring hydronephrosis, subcutaneous implants of fragmented renal medulla from unrelated normal rats decreased blood pressure to normotensive levels. In contrast, medullary implants had no significant effect in rats developing hypertension spontaneously without hydronephrosis. Renal inner medullary plasma flow was low in the obstructed kidneys of hydronephrotic hypertensive SHRs but was elevated in the kidneys of nonhydronephrotic hypertensive SHRs. The hypertension in hydronephrotic SHRs appears to be related to an impairment of the antihypertensive function of the renal medulla. Such an impairment of medullary antihypertensive function does not appear to play a significant role in the hypertension in SHRs without hydronephrosis.  相似文献   
16.
Four random samples representing populations at low (volunteer blood donors), intermediate, (VD clinic patients), high (family contacts of chronic antigen carriers) and very high (male homosexuals) risk of exposure to HBV were surveyed. Among HBsAg and anti-HBs negative individuals an average of 3.3% were found to be anti-HBc positive, and among those with anti-HBs, 19.4% were anti-HBc positive. Anti-HBc, with concurrent anti-HBs and without, was detected more frequently in the high risk samples than in the low risk. Individuals was a past history of acute viral hepatitis were more frequently anti-HBc positive than those without such a history, and anti-HBc positivity was frequently accompanied by serum transaminase elevation. Anti-HBc may persist for many years after an episode of acute hepatitis. In households of carriers, the highest frequency of anti-HBc was observed among spouses, which would argue for the possibility of sexual transmission. A significant excess of females with both types of antibody was observed in families of carriers. Anti-HBc determinations in conjunction with other HBV markers, provide a useful new tool for epidemiologic studies.  相似文献   
17.
18.
This study was concerned with psychotherapists' evaluations of the outcome of therapy. Staff and resident psychiatrists employed in 23-item questionnaire to rate the seccess of psychotherapy with 85 of their inpatients. These were patients for whom psychotherapy constituted a significant part of the treatment that they received in the hospital. The therapists' responses to the questionnaire items were intercorrelated. The results indicated that a major aspect of a psychotherapist's judgment of the success of treatment-as these judgments usually are employed in current psychotherapy research-is the therapist's affective reaction to the patient, Better-liked patients were viewed as having improved more. However, when the therapists' responses were subjected to factor analysis, independent Improvement and Affection factors emerged. It is suggested that when therapists' ratings of success are used in psychotherapy research they should be treated or refined statistically to minimize potential confounding with their affection for patients.  相似文献   
19.
Upon exposure to specific antigen in tissue culture, sensitive lymphocytes released macrophage migration inhibition factor and other lymphokines into the supernatant culture medium. Migration of peritoneal macrophages from nonsensitive animals was inhibited in the presence of such supernatants. However, with previous techniques it was found that an inhibitory effect was present at only low low titers (less than 10(2)). It is therfore of great interest that by increasing cellular density, the total number of cells being kept constant, inhibitory activity can be amplified by a factor as great as 10(10). This amplification was observed only when lymphocytes and macrophages were loosely packed, as by spontaneous sedimentation in a conical test tube. The effect was abolished by dispersing the cell suspension in a flat-bottomed flask or, alternatively, by shaking the test tube so that intimate prolonged intercellular contact was prevented.  相似文献   
20.
Using light and electron microscopic morphometric techniques, the effects of 48 hr of extrahepatic biliary obstruction on hepatocyte structure were examined in the rat. Liver cells near the portal area were compared to those in the centrilobular regions of the hepatic lobule. Observations on the normal animals confirm earlier evidence of quantitative differences in the surface density of organelles in hepatocytes located within different regions of the lobule. A striking difference in the quantity of the Golgi complex in the two areas of the lobule was noted for the first time, with the portal cells containing a significantly greater quantity of this organelle than centrolobular hepatocytes. After 48 hr of total obstruction, most of the previously reported qualitative changes in the canalicular and pericanalicular regions were confirmed. Morphometric analysis at the light-microscopic level showed an increase in the number of cells and a decrease in cell size in those cells near the portal area were compared to those in the centrolobular regions of the helar level demonstrated a significant decrease in both rough and smooth surfaced endoplasmic reticulum in cells of both zones, a finding in marked contrast to the hypertrophy of smooth endoplasmic reticulum suggested by other investigators on the basis of qualitative assessments. There was also a striking decrease in the amount of the Golgi complex, limited to cells in the portal regions. In addition, in all zones a decrease in the volume density of mitochondria and lysosomes was noted, whereas the volume of microbodies was increased. It is suggested that this loss in total membrane material within the cell may be secondary to the degranulation and decrease in total surface area of rough surfaced endoplasmic reticulum, an organelle thought to be responsible in part for the synthesis of new cellular membranes. These observations suggest that present concepts concerning the pathogenesis of cholestatic liver disease require reappraisal.  相似文献   
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