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21.
Animal brain samples received at WHO Collaborating Centre laboratory at National Institute of Communicable Diseases (NICD) during the years 1991-2002 were tested by Seller's stain, Fluorescent Antibody Test (FAT) and Mouse Innoculation Test (MIT) as methods of rabies diagnosis. Negri bodies on Seller's staining could be detected in 52.5% of MIT positive brains, the concordance of this test with MIT was found to be 77.8%. FAT was positive in 91.5% of MIT positive brains, though it showed concordance of 95.7% with MIT results in the total samples. 12.2% of the samples were found positive by FAT of which 1/3rd also showed the presence of Negri bodies when MIT was negative i.e. showing that the virus is present in inactivated form. Thus emphasizing the need for timely and proper collection and transportation of specimens for testing. Seller's stain and FAT give reliable diagnosis of rabies in the brain samples in majority of the cases. MIT being time-intensive test, is of academic value only in decision making as regards initiation of Post Exposure Treatment (PET), it is recommended that in cases where Seller's stain and FAT have yielded negative results the decision to initiate PET should give due consideration to the nature and circumstances of the animal bite and other epidemiological features.  相似文献   
22.
The aim of this chronic experimental study performed in 16 dogs was to determine the effect of epidural infusion of 0.01% clopheline solution on the morphological and histoenzymological characteristics of spinal ganglion neurons. Daily infusions of clopheline at the dose of 15 mg/kg for 14 days caused a decrease in capillary permeability in the spinal ganglia at the injection site and its increase in the intact areas. This finding suggests the changes in the activity of the microcirculatory bed with a disturbed interaction in capillary-neuron system. Analysis of morphometric parameters has demonstrated the presence of some functional and reversible dystrophic changes in spinal ganglion neurons, which were associated with epidural infusion of both clopheline and isotonic solution of sodium chloride. Determination of the activity of oxidation-reduction enzymes, which reflect the course of aerobic and anaerobic processes in spinal ganglion neurons, has shown no significant differences between the groups of animals infused with or isotonic solution of sodium chloride. In conditions of chronic experiment no significant variations were found in RNA content in ganglionic cells at and outside the sites of infusion of clopheline and of isotonic solution of sodium chloride.  相似文献   
23.
We studied follow-up iliac mucosa biopsies from 11 patients with juvenile polyposis and 4 patients with familial adenomatous polyposis who had undergone total colectomy with mucosal proctoectomy with creation of straight ileoanal anastomosis. The biopsies that have been taken from the posterior wall of the terminal ileum show incomplete and focal neocolonic transformation of iliac mucosa. Nevertheless, in most cases iliac mucosa preserved its architectural and histochemical characteristics. Chronic inflammation in iliac mucosa is not typical for patients with polyposis.  相似文献   
24.
Pancreatic hormone amylin and integrity of the gastric mucosa   总被引:1,自引:0,他引:1  
The paper presents experimental findings of some possible mechanisms of protective antiulcerous action of amyline. Amyline is the second beta-cell pancreatic hormone, which has been just recently discovered. The authors have studied the effects of amyline on gastric secretion, mast cell functions, mesenteric lymphatic microvascular contractility, i.e. on individual aggressive and protective factors of the gastric mucosa. Amyline has been found to inhibit basal acid gastric secretion and the secretion stimulated by vagal irritation. The peptide reduces the secretory activities of mast cells. Amyline given to animals increases the heparin saturation index of mast cells and decreases the degranulation index. Amyline-induced stabilization of mast cells appears to followed by the decreased release of histamine and other damaging substances. The stimulating effect of amyline on the contractile activity of mesenteric lymphatic vessels was recorded in rats. Amyline increases both the frequency and amplitude of their contractions. The increased lymph flow that is closely associated with microcirculation promotes the maintenance of tissue homeostasis. Therefore, the protective antiulcerous properties of amyline reduce the action of aggressive agents on the gastric mucosa and stimulate protective ones.  相似文献   
25.
The aim of the present study was to find optimal protocol of immunocytochemical reaction to NeuN nuclear protein for light and laser confocal microscopy, which would exclude the antigen heat unmasking procedure that results in deteriorating the state of the tissue and requires expensive adhesive-coated slides. Best preservation of the antigen was found to be provided by fixation in zinc-formalin and Bouin's fixative (for a period of less than 24 hrs). Two protocols allowing to avoid antigen heat unmasking procedure during demonstration of the NeuN neuronal label in paraffin sections by the light and confocal microscopy are presented.  相似文献   
26.
Morphological features and immunophenotype of mature dendritic cells (DC) generated from the monocytes of healthy donor blood after culture with GM-CSF and IL-4 with the addition of TNF, were studied using light and electron microscopy, as well as flow-cytometry. It was shown that DC were characterized by a number of morphological features such as: large size, eccentrically located nucleus, highly developed system of extensions, large vacuolated cytoplasm, prominent and activated Golgi complex and ribosomal apparatus. Mature DC are characterized by active surface expression of MHC and co-stimulatory molecules (MHC I, MHC II, CD40, CD80, CD86).  相似文献   
27.
In Russia for prevention of influenza in children, aged from 3 to 14 years, the children's live influenza vaccine (LIV), based upon A/Leningrad/134/47/57(H2N2) master strain (LIVI) is used. The need for double immunization appears to be one out of the faulties of this preparation. The study was aimed to comparing the safety, immunogenic activity and prevention of influenza by LIV for adults (LIVII) (A/Leningrad/134/17/57(H2N2 master strain) and LIVI in children aged from 7 to 17 years under similar administration schedule. The safety, the preventive efficacy, humoral and secretory immunity were studied. In total 2486 persons, including 539 children, twice inoculated with LIVI, 971 persons once inoculated with LIVII, and 840 treated by placebo were obserbed. From the data of the clinical observations during 7 days after immunization both vaccines appeared to be low reactogenic. The LIVII advantages in induction of the humoral and secretory antibodies in comparison with children's vaccine had been revealed. Both vaccines were highly efficacious, the efficiency of both preparations was more pronounced after serologic correction of the diagnosis. The results obtained permit to recommend the single immunization by the variant of LIV at the base on A/Leningrad/134/17/57/(H2N2) master strain for prevention of influenza in school children.  相似文献   
28.
Changes of the histological structure of rat's skin were studied two weeks following the daily applications of native birch tar and of purified birch tar, devoid of the components that could be potentially dangerous for humans. The morphometric investigations were performed with the use of computer technologies on the apparatus-programme complex (DiaMorph, Russia). It has been established that the main morphological manifestations of specific dermatotropic activity of birch tar in the present experiment included: epidermal hypertrophy, hyperkeratosis, stimulation of the activity of all dermal cellular elements, intensification of blood supply, reduction of sebaceous glands. Analysis of morphological findings indicates the bioequivalence of the native and purified birch tar in terms of its specific dermatotropic activity.  相似文献   
29.
Using light and electron microscopy structural bases for intracellular, extracellular and integrative regulation of synaptic efficiency and neuron sensitivity were established in rat sensomotor cortex. Intracellular regulation is realized basically through modulation of postsynaptic components of the synapse, while extracellular one is provided by synaptic endings of "recurrent" axons on GABA-ergic relay and interneurons. Integrative regulation is realized by means of concentration of similar axonal terminals in restricted cortical area and arrangement of "neuromediatory" pool.  相似文献   
30.
The aim of this study was to determine which human immunodeficiency virus type 1 (HIV-1) subtypes were circulating in Australia and to correlate the subtypes with risk factors associated with the acquisition of HIV-1 infection. DNA was extracted from peripheral blood mononuclear cells, and HIV-1 env genes were amplified and subtyped using heteroduplex mobility analysis, with selected samples sequenced and phylogenetic analysis performed. The HIV-1 env subtypes were determined for 141 samples, of which 40 were from female patients and 101 were from male patients; 13 samples were from children. Forty-seven patients were infected by homosexual or bisexual contact, 46 were infected through heterosexual contact, 21 were infected from injecting drug use (IDU), 13 were infected by vertical transmission, 8 were infected from nosocomial exposure, and 6 were infected by other modes of transmission, including exposure to blood products, ritualistic practices, and two cases of intrafamilial transmission. Five subtypes were detected; B (n = 104), A (n = 5), C (n = 17), E (CRF01_AE; n = 13), and G (n = 2). Subtype B predominated in HIV-1 acquired homosexually (94% of cases) and by IDU (100%), whereas non-subtype B infections were mostly seen in heterosexually (57%) or vertically (22%) acquired HIV-1 infections and were usually imported from Africa and Asia. Subtype B strains of group M viruses predominate in Australia in HIV-1 transmitted by homosexual or bisexual contact and IDU. However, non-B subtypes have been introduced, mostly acquired via heterosexual contact.  相似文献   
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