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1.
Mother-offspring (MO) relationship quality was investigated to determine its influence on the development of reconciliation--affiliation between opponents shortly after a fight--because it influences what distressed youngsters learn about calming down. Data were longitudinal and cross-sectional observational samples of 38 MO pairs of monkeys across 24 months. An MO relationship quality index (RQI) classified each pair as secure or insecure. Reconciliation emerged in infancy. Secure youngsters had an appeasing conciliatory style, and insecure youngsters had an agitated conciliatory style. Conclusions are that reconciliation develops from the attachment behavior system and MO RQI is related to the particular conciliatory style youngsters develop by affecting how aroused they are by conflict and the subsequent socializing they seek to calm down. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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The effects of sustained stress on response rate and temporal patterning (quarter-life) of rats performing either a previously learned fixed-interval schedule (FI 60) or learning an FI 60 simultaneously with stress onset were determined. Rats lived 24 h/day in operant cages, where they earned all of their food via lever-pressing. During the stress portion of each experiment, one group of rats was able to avoid or escape signalled intermittent footshock (Avoidance/ Escape Group), a second group (Yoked) did not have control over shock termination, a third group never received shock (Control). Shock trials were presented around the clock at approximately 5-min intervals and the stress portion of each study lasted 1-2 weeks. We have previously reported that rats tolerate this paradigm well and avoid/escape 99% of the shock trials. In rats previously trained on the FI task, both rate of responding and quarter-life values were significantly decreased on the first day of stress for both the Avoidance/Escape and Yoked Groups. Food intakes and quarter-life values were not significantly different from the controls by stress Days 3 and 2, respectively. In the acquisition study, controls learned the F1 task by Day 4 as judged by quarter-life of responding. FI task acquisition was significantly impaired in stressed rats compared to controls, not reaching asymptotic performance until Day 9 of stress. There were no major differences between the 2 stress groups in either study. These data demonstrate that stress may impair both the rate and patterning of behavior, and suggest that this rodent paradigm may usefully model some aspects of the effects of stress in humans.  相似文献   

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Serratia marcescens has emerged in the last few years as an important nosocomial pathogen. Many methods for typing this organism have been described. In this study the random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) was shown to be a convenient typing method for S. marcescens. Different combinations of primers previously used for typing other gram-negative bacilli were assessed. The combination of primer HLWL-74 and 1254 gave distinguishable patterns for different serotypes and proved to be the most satisfactory. By applying this combination to 175 isolates of S. marcescens, which could be classified into 38 groups on the basis of serotyping and phage typing, 73 different RAPD patterns with good reproducibility were obtained. This is, to our knowledge, the first application of the method to a large collection of S. marcescens representing a wide range of serotypes.  相似文献   

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The course of HOCM is characterized by a slow progression. Symptoms can often be influenced favourably by medical treatment. Altogether there is some difference between the course of untreated and the propranolol-treated patient groups which is, however, not statistically significant. Furthermore, the rate of sudden death is uninfluenced. Comparing clinical and haemodynamic results in medicically treated patients we find a reduction of the outflow tract obstruction in case with clinical improvement but not a reduction of the enddiastolic pressure. Independent on the clinical course there was a significant increase of the enddiastolic pressure after 5.5 years. We may conclude that there is a progredient process of hypertrophy which is uninfluenced by the obstruction and by conservative management. The best results are obtained in the operated group. According to our results a surgical intervention should possibly be considereed more generously.  相似文献   

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In a cattle herd in North Rhine-Westphalia a series of eight abortions occurred between 15th August and 14th October, 1996. Four of the aborted fetuses were histopathologically, virologically, bacteriologically and parasitologically examined. A multifocal necrotising encephalitis was observed in two fetuses. In addition, the liver of two fetuses and the placenta of one fetus contained infected foci. In three fetuses protozoan stages were detected which were identified as N. caninum by immunohistochemistry. A polymerase chain reaction conducted with histological material revealed N. caninum-DNA in the placenta of an aborted fetus. When seven cows that had aborted were tested for antibodies directed against N. caninum, six animals were positive by immunofluorescence and all seven by immunoblotting. The serological examination of the entire herd revealed a high herd seroprevalence of antibodies directed against N. caninum. Potential modes of infection with N. caninum in the herd are discussed, in particular the possibility of exposure to a point source (definitive host).  相似文献   

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Cysteine string proteins (CSPs) are synaptic vesicle proteins thought to be involved in neurotransmitter release. To obtain more information about the function of these proteins motor nerve terminals of wild type and CSP null mutant Drosophila larvae were depolarized and excitatory postsynaptic currents (EPSCs) were recorded with an extracellular electrode at 16-18 degrees C. At this temperature the amplitude of average EPSCs was reduced and the time constant of the exponential fit of the current decay was increased in CSP null mutant compared to wild type larvae. The number of quanta released per pulse was not different but the time course of release was distributed differently in CSP null mutant and wild type larvae. In measurements of the latency of quantal EPSCs the probability of release after a pulse reached a lower peak value and the decay after the peak was delayed in CSP null mutant compared to wild type larvae. In addition facilitation in response to twin-pulse stimulation was slightly increased at low levels of release in CSP null mutant larvae. It is concluded that CSPs are involved in neurotransmitter release and help to synchronise evoked release at nerve terminals.  相似文献   

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A survey attempted to determine the extent to which cows are being inseminated when not in oestrus. The method used to check the farmers' diagnoses of oestrus was based on peripheral plasma progesterone concentrations analysed by radioimmunoassay. Of 141 cows examined in this way, a total of 30 (21-28 per cent) showed abnormalities of the progesterone levels. The fertility within this group was very poor with only two of the cows being known to have conceived to the service in question.  相似文献   

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The epidemiology of clinical cases of campylobacter in temperate climates shows a striking seasonality. In the search for a seasonal environmental reservoir changes in the carriage rate and population size of campylobacters in bovine hosts with time have been measured. Most probable number (MPN) methodology was used to enumerate thermophilic campylobacters in samples taken from the small intestines of beef cattle at slaughter and the fresh faeces of four dairy herds and new-born calves. Statistical analyses revealed significant evidence for seasonal periodicity in the data from dairy herds (P = 0.044). Not only was there a departure from constancy within a 12-month interval but these data revealed a true seasonality, that is, the same periodicity in numbers from one year to the next. Each herd had two peaks per year, in approximately spring and autumn. Peaks coincided in herds on neighbouring farms but those on farms in the north preceded those on farms in the south by 2 and 1 months, respectively (P = 0.0057). Intestinal carriage by beef cattle at slaughter was 89.4% (n = 360) with an average MPN campylobacters per gram fresh weight (MPN gfw-1) of 6.1 x 10(2). Average MPN gfw-1 in faeces from the dairy herds and calves were 69.9 (S.D. 3) and 3.3 x 10(4) (S.D. 1.7 x 10(2)). There was no evidence of seasonal periodicity in the size of the campylobacter population in beef cattle at slaughter. Calves were campylobacter free at birth but became colonized with a few days.  相似文献   

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The paper analyzes the standard legal and methodological assurance of the quality and safety of animal food raw materials and foodstuffs (meat, meat products, fish, shellfish, crayfish and their processing products) by the parasitic purity rates according the requirements under the Russian Federation's laws "On Sanitary and Epidemiological Well-Being of the Population", "On Protection of Consumer's Rights", "On Certification of Products and Services", those of SanPiN, such as 2.3.2.560-96 "Sanitary Requirements for the Quality and Safety of Food Raw Materials and Foodstuffs" and 3.2.569-96 "Prevention of Parasitic Diseases in the Russian Federation".  相似文献   

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Of four media tested, a tissue culture medium supplemented with a bovine serum albumin-oleic acid complex provided the best leptospiral growth and cost efficiency.  相似文献   

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Prototheca spp. were detected in 146 (48.7%) of culturally examined fecal samples of cattle, using the selective medium, developed by Pore (1973). 114 fecal samples (78.1%) contained a monoculture of Prototheca (P.) zopfii, while 10 fecal samples (6.8%) contained a monoculture of P. moriformis. In further 22 fecal samples (15.1%) a mixed culture of P. zopfii and P. moriformis was detected. The results of this study permit to conclude that cattle can harbour and shed Prototheca spp. in variable frequency.  相似文献   

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The goal of this study was to determine whether Helicobacter pylori or similar bacteria are present in the abomasum of cows. The abomasa of 112 clinically healthy cows were examined at slaughter. Prior to macroscopic examination, samples for bacteriological and histological examination were obtained from the fundus and from the pylorus. Bacteriological examination of the abomasal mucosa included the urease test, the microscopic examination of a Gram's stained smear, and culture on various solid media. Samples from the pylorus (63) were more often positive in the urease test than those from the fundus (35). Examination of Gram's stained smears revealed two groups of suspicious microorganisms; spiral-shaped and rod-shaped bacteria, whereby the latter could not be differentiated morphologically from Helicobacter pylori. Spiral-shaped bacteria were more often isolated from the pylorus (101 samples) than from the fundus (30 samples). The bacteria that resembled Helicobacter pylori were found in seven samples from the pylorus and in seven samples from the fundus. Helicobacter pylori was not cultured in any of the abomasal samples. Tissue samples from the fundus and pylorus were stained with hemalum and eosin and with silver according to Warthin-Starry. All but one abomasum had diffuse infiltration of lymphocytes and plasma cells. Lymphocytic follicles were observed in 109 abomasa. Neutrophils were seen in four abomasa, eosinophils in 37 and parasitic lesions in 20. As in the Gram's stained smears, spiral-shaped and rod-shaped bacteria were seen in silver-stained smears. Spiral-shaped bacteria were found in the pylorus of 96 abomasa and in the fundus and pylorus of one abomasum. The rod-shaped bacteria could not be differentiated from Helicobacter pylori by light microscopy. They were seen in glandular lumina of the superficial region of the mucosa in 97 abomasa. They were limited to the pylorus and fundus in 16 and 59 cases, respectively, and occurred in both these areas in 23 cases. The results of this study indicate that spiral-shaped bacteria may be found frequently in the bovine abomasum. Further investigations are required to determine whether these bacteria are associated with the inflammatory lesions that were observed and whether they play a role in the pathogenesis of abomasal ulcers.  相似文献   

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