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41.
Despite the potential of feline immunodeficiency virus (FIV) as an animal model for human immunodeficiency virus (HIV) studies, the long term effects of naturally-occurring infection have not been determined. HIV infection causes an ongoing deterioration in immune function which directly correlates with disease, in particular acquired immunodefciency syndrome (AIDS). However, it is not known whether FIV-induced immunosuppression is progressive or related to the clinical condition. This study examined changes in lymphocyte subset numbers of serial samples, taken from cohorts of FIV-positive and FIV-negative cats over an 18-month period. FIV-positive cats were clinically staged as asymptomatic carriers (AC) or cats with AIDS-related complex (ARC), and FIV-negative cats matched and staged on the basis of similar diseases. During the course of the study, 4 FIV-positive cats developed AIDS, classed as the terminal stage of infection. There were no significant differences in the mean absolute numbers of any lymphocyte subset between the onset (to) and the completion (t18) of the study. Similarly there were no significant changes in subset numbers during the 18 months preceding the development of AIDS. While the study period was brief and the sample sizes small, it is postulated that FIV infection in Australia may not necessarily cause progressive immunodeficiency and that FIV-induced immunosuppression (as measured by subset analysis) may not be well correlated with the clinical status of the infected cat.  相似文献   
42.
Nasopharyngeal cryptococcosis   总被引:1,自引:0,他引:1  
Naturally occurring cryptococcosis in five cats, a dog and a koala is described. Involvement of the nasopharynx was documented in all patients, and nasopharyngeal mass lesions accounted for the major presenting complaints in four. Signs referable to nasopharyngeal disease included snoring, stertor, inspiratory dyspnoea and aerophagia. Diagnoses were made by caudal rhinoscopy using a retroverted flexible endoscope, vigorous orthograde flushing with saline, or at necropsy. Concurrent cryptococcal rhinitis was present in all cases, although involvement appeared limited to the caudal nasal cavity in most cases. Typical signs of nasal cavity disease, such as sneezing and nasal discharge, were often absent. Treatment of nasopharyngeal cryptococcosis should include physical dislodgement or debulking of lesion(s) to provide immediate alleviation of upper airway obstruction, followed by systemic antifungal therapy to eliminate residual infection from the nasal cavity. Infections caused by Cryptococcus neoformans var gattii accounted for a disproportionately large number of these cases.  相似文献   
43.
Objective
To describe a case of meningoencephalitis caused by Balamuthia mandrillaris in an orang utan.
Design
A pathological case report.
Animal
A 20 years old male orang utan (Pongo pygmaeus).
Procedure
The disease process was investigated by clinical pathology, necropsy, histopathology and immunofluorescence labelling.
Results
The orang utan developed sudden onset of depression, lethargy, inappetence and apparent head pain. The condition was considered to be related to a 2 year history of upper and lower respiratory disease, and the animal was placed on antibiotics after extensive testing. By the seventh day the animal had become ataxic and disoriented and a brain abscess was suspected. He died on the ninth day of illness. At necropsy, and subsequent sectioning, the brain showed multiple circular, soft, white to grey brown areas of varying size, the largest being in the left temporal (3.5 cm diameter) and right occipital (2.5 cm diameter) regions of the cerebrum. Histological examination of these regions revealed many amoebic trophozoites and occasional cysts associated with areas of haemorrhage and inflammatory necrosis. The trophozoites were packed in perivascular spaces and their nuclei often contained two or more prominent nucleoli. Immunofluorescent labelling of histological sections suggested that the agent was B mandrillaris.
Clinical implications
This report provides further evidence that B mandrillaris , a free living amoeba, can act as a pathogen in animals as well as people, and cause fatal meningoencephalitis. Along with Naegleria and Acanthamoeba spp, B mandrillaris should be considered amongst the causes of acute onset meningoencephalitis in animals.  相似文献   
44.
45.
Keto-aldehydes and cell division   总被引:10,自引:0,他引:10  
Many problems are left open in this article. Its publication may be excused by the suffering cancer causes, which urges the researcher to publish as soon as he thinks he may have found a new trail, which also may be taken by others. What emerges clearly is that SH groups, with their specific reactivities, offer a hopeful target in the search for cancerostatic substances, among which the natural repressor of cell division may hold out the most promise. The glyoxal derivatives also have antiviral properties (7, 16) and may be in the center of a hitherto unknown system of equilibria which deserves a thorough study. The low molecular weight of the glyoxal derivative reported justifies the hope of an early clarification of its structure, as well as its synthesis (17).  相似文献   
46.
An antigenic site, which was not immunochemically demonstrable in the intact kappa light polypeptide chain, was exposed by enzymatic cleavage of the kappa chain into its variant half and constant half. This antigenic site located in the constant region the kappa chain was detected immunochemically by several antiserums that had specificity for this site. Treatment of an intact kappa chain with a dissociating agent resulted in the exposure of the hidden antigenic site, which was as readily detected in the unfolded polypeptide chain as in the isolated constant half.  相似文献   
47.
A new approach to mixture analysis has been applied to the direct detection of various alkaloids in plant materials. The method requires absolutely no sample treatment. Results are presented for cocaine, morphine, papaverine, coniine, and atropine. The signal-to-background characteristics are superior to those of conventional mass spectrometry. Sensitivity is sufficient to detect and identify between 1 and 10 nanograms of alkaloid.  相似文献   
48.
An extract of Zygadenus gramineus, "death camas," from which most of the resins had been removed was given intravenously to sheep prepared for recording blood-pressure and respiratory movements. Following the intravenous injection of this extract there occurred a respiratory inhibition which in the case of the injection of larger amounts of the extract was followed by asphyxia-like rises of blood-pressure. The graphic record of this asphyxial condition was practically duplicated by closing the tracheal cannula for a short time following the recovery of the animal from the effects of the plant extract. Although, from a field standpoint, no satisfactory antidote has been found, it has been demonstrated that caffein sodio-benzoate possesses marked powers of stimulation for the respiratory center affected by the depressive substances found in Zygadenus gramineus.  相似文献   
49.
已知用生长激素(PST)处理美国的肥育猪可提高饲料报酬、生长速度和胴体的瘦肉率。由于中国猪比美国猪更肥一些,饲料报酬较低和生长较慢,因而设想用生长激素处理中国猪可能更有效。本试验在肥育期28天内用 PST 处理北京黑猪(由中国地方猪,约克夏和巴克夏杂交育成),在每天饲喂4次的个体饲养组(n=12,6头公猪和6头母猪)中,每天注射2毫克和4毫克 PST 的猪,其饲养报酬分别提高22.3%和30.6%(P<0.01),主要是提高了生长速度(分别比对照组快24.4%和30.2%)(P<0.01),而对饲料摄入量没有影响。每天注射 PST 2毫克(28天),群饲猪(6头/圈,4圈/处理组)得到了类似的结果:饲料报酬提高22.7%(P<0.01);生长速度提高25%(P<0.01)。屠宰分析的结果表明,每天注射2和4毫克 PST 的猪,最后肋膘厚率平均降低19.2%(P<0.01)。剥离分析半片胴体的结果表明,PST 处理猪的疫肉总量和瘦肉率分别提高21.4%和13%(P<0.01),而总脂肪量和脂肪率则分别降低16.7%(P<0.05)和22%(P<0.01)。胴体的化学分析获得类似结果。PST 处理猪的背最长肌的 ...  相似文献   
50.
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