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The cytochrome b gene of the Tawny Owl (Strix aluco), Hume's Tawny Owl (Strix butleri) and the African wood owl (Strix woodfordii) was amplified by polymerase chain reaction (PCR) and partially sequenced (300 base pairs). Sequences differ substantially (9 to 12% nucleotide substitutions) between these taxa indicating that they represent distinct species, which is also implicated from morphological and biogeographic differences. Using cytochrome b sequences of S. aluco, S. butleri, S. woodfordii, Athene noctua and Tyto alba phylogenetic relationship were reconstructed using the "maximum parsimony" principal (PAUP 3.1.1) and the neighbour-joining method (MEGA). 相似文献
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Trained 4 tawny owls to discriminate simultaneously between blue (437 nm) and green (547 nm) lights and between red (672 nm) and green (547 nm) lights. The relative luminances of the stimulus pairs were randomly varied. This procedure, together with the results of test trials, suggests that it is highly unlikely that the discriminations were made using cues based on the luminances of the stimuli. The large number of trials to learn the discrimination and the results of various procedural changes suggest that while the tawny owl does possess color vision, the wavelength of light is not of great importance in controlling its behavior. The wavelength discrimination ability of the tawny owl is compared to that of other species, and it is suggested that color vision in the tawny owl may be mediated by either a dichromatic or an anomalous trichromatic visual system. The evolution of such a system is considered. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Relapse prevention in abstinent cocaine addicts remains a major focus of drug addiction therapy. We used a rat model of cocaine addiction that focused on cocaine-seeking behavior elicited interoceptively and by conditioned stimuli. Each of 18 rats could self-administer a maximum of 20 intravenous cocaine injections (1.5 mg/kg) per session per day. To prevent initiation of responding by cocaine itself priming injections were never administered. Although cocaine was available beginning every session the rats displayed a self-imposed period of abstinence followed by a period of rapid consumption. The abstinence period was variable among rats but consistent for individual rats. In experiment 1 we studied the contribution of a CS+ (stimulus light and lever retraction) to the motivation to initiate and maintain a cocaine self-administration episode. We compared the number of responses the rats emitted to receive the first and subsequent injections of the day between a group responding on a fixed-ratio (FR) schedule (n = 6) and a group responding on a second-order (SO) schedule (n = 5) of reinforcement. For all rats the number of responses per injection was raised daily until a rat failed to consume more than four injections. The SO group was able to emit approximately four times as many responses as the FR group to obtain their first and subsequent injections. In experiment 2 (n = 7) responses during extinction were counted with and without the CS+. Responding was greater in the presence of the CS+ than in its absence. The present model demonstrates that the motivation to self-administer cocaine is variable and greatly enhanced by conditioned stimuli. 相似文献
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Obtained the electroretinographic (ERG) responses to single light flashes and to flickering lights in the tawny owl (Strix aluco), using 2 tawny owls from 300 that had been in captivity 6 mo. The waveform of the single-flash responses indicated that the owl possesses a duplex retina. Spectral sensitivity was determined with light flickering at 6 and 25 Hz. The sensitivity curve obtained from the 6-Hz responses had a broad maximum between 500 and 525 nm. The 25-Hz sensitivity curve was narrow with a peak at about 600 nm. The sensitivity curves were compared with behaviorally measured sensitivity curves of the same species and with ERG-measured sensitivity curves of the pigeon. A close agreement was found between 25-Hz curve and the pigeon red modulator. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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A female adult barred owl (Strix varia) had been hurt by a car. Its general status declined gradually within 2 wk with anorexia and inactivity. Necropsy examination revealed marked multifocal pale areas in liver, emaciation, and mild airsacculitis and pericarditis. Histopathologic examination revealed severe acute multifocal hepatic necrosis with numerous protozoal tachyzoites within necrotic foci and in the cytoplasm of hepatocytes and macrophages. These tachyzoites stained with an indirect immunohistochemistry method for Toxoplasma gondii antigens. This is the first reported case of hepatitis resulting from toxoplasmosis in a raptor. 相似文献
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Eosinophilia occurs as a concomitant sign in multiple diseases of different etiology. Especially its occurrence in malignant diseases is still unknown. In three cases of primary sarcoma of the small intestine a constant eosinophilia is described. In one case this pronounced eosinophilia was present long before the final diagnose was made. The eosinophilic count was highest in the presence of clear symptoms of obstruction and normalized after surgical removal of the tumor. In one case a relapse was indicated by an increasing eosinophilic count. It is difficult to diagnose the sarcoma of the small intestine especially in its early stage because of the lack of typical symptoms. Concerning the described cases it is therefore pointed out, that in connection with undifferentiated abdominal complaints an obscure eosinophilia should be considered to be due to sarcomatous small bowel disease. 相似文献
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The subcellular localization of enterokinase is controversial. In this study, enterokinase was extracted from a soluble fraction and a brush border fraction of rat small intestine by differential centrifugation. The soluble fraction contained 41% of the initial enterokinase activity while the brush border fraction contained only 4.6% of the initial activity. In contrast, alkaline phosphatase monitored as a brush border marker, yielded 26.3% in the brush border fraction and only 6% in the soluble fraction. Further separation of the soluble fraction on a Sepharose 4B column revealed three peaks of enterokinase activity. One small peak (3%) of a bound enzyme (Mr, 2 - 10(6)) and two larger peaks of free enzyme (Mr, 3 - 10(5) and 9 -10). In contrast, alkaline phosphatase major fraction was in a high molecular weight peak of bound enzyme. When the brush border fraction was chromatographed only a single peak of bound enterokinase and alkaline phosphatase were found. In the lower part of the small intestine, no brush border-bound enterokinase was found, while the peak of alkaline phosphatase was the same as in the upper intestine. These data suggest that enterokinase activity in the rat intestine is mainly in a free form localized in the mucin and soluble fraction and to a negligible extent in the brush border. 相似文献
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Mirrors have been used to focus attention to aspects of the self (e.g., to known strategies, standards). We hypothesized that this could be important for students with hyperactivity/inattention, who typically direct attention outward to external novelty. In this study, we administered a partially solvable word puzzle to 43 middle school students, with and without hyperactivity/inattention, in the presence and absence of a mirror, counterbalanced for condition and form order. Differences between students with hyperactivity/inattention and comparisons in accuracy were found only in the no mirror condition. Furthermore, the beneficial effect of the mirror for children with hyperactivity/inattention was most pronounced for those who looked at the mirror. Findings were interpreted in terms of their potential to remedy the production deficits of these children. 相似文献
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This article describes the long-term consequences of successful cardiovascular disease (CVD) prevention and its influence on premature mortality in Finland, with special reference to North Karelia. Active community-based CVD prevention began in 1972 in the province of North Karelia (population, 180,000). Since 1977, active preventive work has been carried out nationwide, taking advantage of the experience from North Karelia, which continued as a demonstration area for integrated prevention of noncommunicable diseases. Comprehensive community-based interventions as part of WHO interhealth and CINDI programmes in North Karelia and nationwide aimed at changing the target risk factors and health behaviours (serum cholesterol, blood pressure, smoking, diet) at the population level. Age-adjusted mortality rates for CVD, coronary heart disease (CHD), cerebrovascular disease, all cancers, lung cancer, accidents and violence, and all causes in the population aged 35-64 years from the pre-programme period (1969-71) to 1995 were the main measures of the outcome. Among men there was a great reduction in deaths from CHD, CVD, cancer, and all causes in the whole country. From 1969-71 to 1995 the age-standardized CHD mortality (per 100,000) decreased in North Karelia by 73% (from 672 to 185) and nationwide by 65% (from 465 to 165). The reduction in CVD mortality was of the same magnitude. Among men, CHD mortality decreased in the 1970s, as did lung cancer mortality in the 1980s and 1990s, significantly more in North Karelia than in all of Finland. Among women there was a great reduction in CVD (including CHD and stroke) mortality and all-causes mortality, but only a small reduction in cancer mortality. These results show that a major reduction in CVD mortality among the working-age population can take place in association with active reduction of major risk factors, with a favourable impact on cancer and all-causes mortality. 相似文献
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It was taken 32 male Wistar rats, weighting between 130 g and 150 g, free feeding, to study the total and specific activities of lactase, invertase and maltase of small intestine of rats. The animals were divided by chance in 3 experimental and 1 control group. 1. group--Aloxanic diabetes rats: treated with 1 unit of NPH insulin every day: after the 4th day of aloxane administration, all rats were killed. 2. group--Aloxanic diabetes rats--treated for 5 days with 1 unit of NPH insulin every day; after the 5th day until the 7th they were treated with 4 units of NPH insulin and were also killed. 3. group--Hyperinsulinism rats--Normal rats were treated for 4 days with 4 units of NPH insulin every day. After the 5th day they were killed. 4. group--Control group--Normal rats, free feeding. They were observed during 4 days and were also killed. The results showed that none difference was observed in the 4 groups of rats about the total and specific activities of lactase, invertase and maltase of the small intestine. In this study, all the animals with aloxanic diabetes were treated with insulin. Then, it is possible that the insulin inhibited the stimulator effect of the diabetes upon the dissacaridases of the small intestine of the rats. 相似文献
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Surgery of the small intestine 总被引:1,自引:0,他引:1
DE Freeman 《Canadian Metallurgical Quarterly》1997,13(2):261-301
Although earlier reports describe a poor prognosis for small intestinal surgery in the horse, there is growing evidence that the short-term survival rate can exceed 80%. In addition to advancements in surgery and aftercare, early referral contributes considerably to the improved prognosis. Surgical procedures that restore anatomic and physiologic continuity to close to normal can minimize postoperative complications. Jejunojejunostomy carries a better prognosis than jejunocecostomy, probably because the latter involves anastomosis between two intestinal segments with dissimilar functions. Careful technique can reduce the prevalence of complications, such as postoperative ileus and serosal adhesions. 相似文献
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Six cases of perforation of the small intestine, one secondary to anaphylactoid purpura and five spontaneous, are reported. Ingestion of an iced drink acted as a trigger in two cases. A vascular genesis is put forward to explain the aetiopathogenesis of two cases and it is noted that perforation of this type is present in the final ileal ansa, at the mesenterial margin. In three cases, histology revealed the presence of double refraction crystal. These came from vegetal residues and are probably capable of penetrating from the lumen into the mucosa causing a foreign body reaction, abscess and subsequent perforation. In these cases, perforation occurred in an ansa located further away than the last ileal ansa (about 3 m) and on the mesenterial margin. Intestinal resection and subsequent end-to-end, single layer anastomosis were performed in all cases. 相似文献
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The ganglioneuroma is a rare, benign tumor of the small bowel. The clinical symptomatology and morphology of the tumor are presented in detail. The differences in histopathology between ganglioneuroma and eosinophilic granulomatous polyp are discussed. Therapy should be resection of the tumor. 相似文献
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A case story of malignant melanoma is presented. The tumour was localised to the jejunum. The symptoms, diagnosis and treatment are described and the pathogenesis is discussed. 相似文献
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Merozoites of an Atoxoplasma species were present within parasitophorous vacuoles in the cytoplasm of leucocytes in the blood vessels in the small intestine of the greenfinch (Carduelis chloris). The merozoites indented the nucleus of the leucocytes. Merozoites, macrogametes, and microgamonts were present in the epithelial cells of the intestines. No merogony was observed. Experiments provided circumstantial evidence linking disporocystid-octozoic oocysts with the blood and intestinal infections. 相似文献
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A case of serious, recurrent enterorrhagia is reported. The cause could not be identified with normal diagnostic tools and was discovered only after explorative laparotomy. The finding was benign ulcerated tumour of the small intestine, histologically defined as fibroma with fluorishing cellularity. 相似文献