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Lyt phenotype of in vitro generated alloreactive cytotoxic T lymphocytes (CTL) and their precursors in B6-Lyt-1.1 (Thy-1.2, Lyt-1.1, Lyt-2.2) congenic strain of mice was studied. The generation of CTL in vitro was completely abrogated by pretreatment of responder cells with antisera to Thy-1.2, Lyt-1.1 and Lyt-2.2 antigens and complement. Mixing of anti-Lyt-1.1-pretreated cells with anti-Lyt-2.2-pretreated cells did not restore CTL generation indicating that both Lyt antigens are expressed on the same precursor cell population. The effect of anti-Lyt sera was specific because the generation of CTL was prevented only when cells from strains possessing appropriate Lyt alleles were pretreated. CTL were eliminated by lysis with anti-Thy-1.2 serum and strongly reduced by anti-Lyt-1.1 and anti-Lyt. 2.2 sera. Nevertheless, a small but significant proportion of CTL was insensitive to lysis with anti-Lyt sera. These data indicate that a phenotype of precursor cells and of majority of CTL is Thy-1.2+ Lyt-1.1+ Lyt-2.2+.  相似文献   
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Spatial adjacency of stimulus source and response site has been proven important for learning of simple behavioural tasks, including auditory quality and location discrimination. We investigated effect of sound source position (adjacent or not adjacent to manipulanda) on learning and performance of a complex auditory recognition memory task. Spatial adjacency of stimuli and manipulanda improved learning of a simple auditory directional task, which was an intermediate stage of training. In contrast, no improvement of learning and performance of the recognition task was found.  相似文献   
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The aim of this paper is an analysis of clinical documentation and results of autopsy of 21 patients (pts) who died of invasive aspergillosis (IA) in the Institute of Tuberculosis and Chest Diseases in years 1993-2000 and the assessment of predisposing factors for IA. In 17 pts IA was the main and in other 4 only an accessory cause of death. All pts were treated with corticosteroids and/or cytostatic drugs--because of lung cancer (11 pts), cancer in other site (2 pts), haematologic disorders (2 pts), Wegener's granulomatosis (1 pt), polymyositis (1 pt), idiopathic pulmonary fibrosis (1 pt) and other diseases (3 pts). In 15 out of 21 pts granulocytopenia was revealed (from 0.008 x 10(9)/L to 0.82 x 10(9)/L) on an average one month before death. In 15 pts IA was limited to the lungs, in 6 others there were also fungal lesions in brain, kidneys, liver, spleen and heart. Pts with disseminated form of IA had significantly lower granulocyte count and were treated with higher doses of corticosteroids than others. Immunosuppressive drugs and granulocytopenia can be regarded as predisposing factors. Fatal course of IA depended also on the late diagnosis.  相似文献   
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On the basis of biological characteristics of murine transplantable mammary adenocarcinoma 16/c, experimental conditions optimal for chemotherapeutic experiments were defined. Sensitivity of primary tumor and lung metastases to the treatment with drugs used in breast cancer therapy: cyclophosphamide, 5-fluorouracil and adriamycin was confirmed. These drugs were significantly more effective in combination than when administered as monotherapy. Antimetastatic but not antitumor effect of 5-fluorouracil could be potentiated by using albumin microspheres as a carrier. Usefulness of the tumor model system in experimental chemotherapy is discussed.  相似文献   
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Vapor phase corrosion inhibitors were used to investigate the antimicrobial activities and anticorrosion of aluminum alloy. Aspergillus flavus, A. niger, A. versicolor, Chaetomium globosum and Penicillium funiculosum had moderate to abundant growth on the aluminum alloy AA 1100 at Aw 0.901, while there was less growth at Aw 0.842. High humidity stimulated microbial growth and induced microbial corrosion. Dicyclohexylammonium carbonate had a high inhibitory effect on the growth of test fungi and the microbial corrosion of aluminum alloy, dicyclohexylammonium caprate and dicyclohexylammonium stearate were the next. Aluminum alloy coating with vapor phase corrosion inhibitor could prevent microbial growth and retard microbial corrosion.  相似文献   
18.
Lee HS  Ku SK 《Acta histochemica》2004,106(2):171-178
Distribution patterns and the relative frequency of different types of endocrine cells were demonstrated in the alimentary tract of the grass lizard, Takydromus wolteri, using nine specific antibodies raised against mammalian regulatory peptides. The alimentary tract of the lizard was divided into six portions from the esophagus to the rectum. Most endocrine cells were found in the epithelial lining and were generally spindle shaped with long cytoplasmic processes ending in the lumen (open cell type), whereas cells that were spherical in shape (closed cell type) were occasionally found in gastric, esophageal and intestinal glands. Endocrine cells were stained for the following regulatory peptides: bovine Sp-1/chromogranin (BCG), serotonin, somatostatin, gastrin, cholecystokinin (CCK)-8, glucagon, insulin, human pancreatic polypeptide (HPP) and secretin. Cells stained for BCG and serotonin were present throughout the entire gastrointestinal tract and they occurred with the highest frequency in stomach and pylorus, respectively. Somatostatin-positive cells were detected throughout the entire gastrointestinal tract except for the esophagus and large intestine, and were most predominant in pylorus and duodenum. Cells stained for gastrin were restricted to the pylorus and duodenum and occurred with a relatively low frequency. CCK-8-positive cells were observed from pylorus to small intestine and showed the highest frequency in the pylorus. Glucagon- and insulin-containing cells were located in duodenum and small intestine but were found only rarely. HPP-stained cells were detected in duodenum and small intestine with the highest frequency in duodenum. Cells stained for secretin were restricted to duodenum and were found only rarely. In conclusion, distribution patterns and the relative frequency of these endocrine cells correspond well with previous reports on distribution patterns of endocrine cells in reptile species but some deviating patterns were also observed.  相似文献   
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Five TLRs are thought to play an important role in antiviral immunity, sensing viral products and inducing IFN-alpha/beta and -lambda. Surprisingly, patients with a defect of IRAK-4, a critical kinase downstream from TLRs, are resistant to common viruses. We show here that IFN-alpha/beta and -lambda induction via TLR-7, TLR-8, and TLR-9 was abolished in IRAK-4-deficient blood cells. In contrast, IFN-alpha/beta and -lambda were induced normally by TLR-3 and TLR-4 agonists. Moreover, IFN-beta and -lambda were normally induced by TLR-3 agonists and viruses in IRAK-4-deficient fibroblasts. We further show that IFN-alpha/beta and -lambda production in response to 9 of 11 viruses tested was normal or weakly affected in IRAK-4-deficient blood cells. Thus, IRAK-4-deficient patients may control viral infections by TLR-3- and TLR-4-dependent and/or TLR-independent production of IFNs. The TLR-7-, TLR-8-, and TLR-9-dependent induction of IFN-alpha/beta and -lambda is strictly IRAK-4 dependent and paradoxically redundant for protective immunity to most viruses in humans.  相似文献   
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