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41.
A pineal tumour in a 27-year-old male is presented with the characteristic histological features of a pineal malignant rhabdoid tumor (MRT) with chondroid formation. Occasionally, tumor cells contained a single well-demarcated hyaline globular inclusion within the cytoplasm adjacent to the nucleus. The stroma of these tumors tends to be densely hyalinized and become chondroid. Immunohistochemical staining was positive for vimentin, epithelial membrane antigen, chromogranin A, synaptophysin, neuron-specific enolase, S-100 protein, and muscle actin. Despite surgery and radiochemotherapy, the tumor recurred in the pineal region and metastasized to the lower lobe of right lung. The patient died 2 years after the initial diagnosis. This is the second published case of central nervous system-MRT appearing in an adult. The clinical and pathological features of pineal MRT in this patient are presented.  相似文献   
42.
The carcinogenic potential of chloroform was evaluated in a short-term carcinogenicity testing system using CB6F1 rasH2-Tg (rasH2-Tg) mice. Chloroform was administered to rasH2-Tg males at doses of 28, 90, or 140 mg/kg and rasH2-Tg females at 24, 90, or 240 mg/kg by oral gavage for 26 weeks. Wild-type (non-Tg) male and female mice received doses of 140 mg/kg and 240 mg/kg, respectively. N-methyl-N-nitrosourea was administered to rasH2-Tg mice by single intraperitoneal injection (75 mg/kg) as a positive control. In both the rasH2-Tg and non-Tg mice, there was no significant increase in the incidence of neoplastic lesions by chloroform treatment. The incidence of hepatocellular foci in the rasH2- and non-Tg females receiving 240 mg/kg was increased. Forestomach tumors and malignant tumors occurred in most of the rasH2-mice in the positive control group. Swelling or vacuolation of hepatocytes, a toxic change induced by chloroform, occurred in both the rasH2-Tg and non-Tg mice. It is concluded that chloroform, a putative human noncarcinogen, did not show evidence of carcinogenic potential in the present study using rasH2-Tg mice. This study suggests that the rasH2-Tg mouse model may not be appropriate for detecting nongenotoxic carcinogens. However, the sensitivity of rasH2-Tg mice to nongenotoxic carcinogens should be assessed with consideration of the results from the other ILSI-HESI project studies.  相似文献   
43.
This study was intended to determine the number and density of both retinal ganglion cells and the oil droplets of cone photoreceptor cells in brown-eared bulbul (Hysipetes amaurotis). For this study birds were killed with proper dose of anesthetic (pentobarbital, 30 mg/kg), and the eyes were removed from the orbital cavity to isolate the retina. For the ganglion cell study retinal whole-mount specimens were prepared and stained with 0.1% cresyl violet. The different types of oil droplets were counted from color microphotographs of freshly prepared retinal samples. The mean total number of ganglion cells was estimated at approximately 2.5×106; with an average density of 16 523 cells/mm2. Two high-density areas, namely the central area (CA) and the dorso-temporal area (DTA), are located in the central and dorso-temporal retinas, respectively, in bulbuls (24 032 cells/mm2 in the CA; 23 113 cells/mm2 in the DTA). Small ganglion cells persisted in the highest density areas, whereas the largest soma sizes were found in the lowest density areas of the retina. Four types of different colored oil droplets — red, orange, green and clear — were identified with an average density of 29 062/mm2. Among the different colors, the green oil droplets had a significantly higher population (13 083/mm2) than the others across the retina. The central retina had a significantly higher number of all types of oil droplets, at a density of 60 552/mm2. The density and size of the different colored oil droplets were inversely related across the regions of the retina. Taken together, it is concluded that the CA of the retina is an excellent quality area for visual perception due to peak density of ganglion cells and oil droplets. Moreover, each specific oil droplet makes a distinct contribution to visual perception, thereby ensuring that the bird has a retina that best matches its natural environment and feeding behavior.  相似文献   
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45.
61 patients suffering from chronic pancreatitis were studied in order to clarify the psychosomatic aspects of this disease. They were classified into 5 types, out of which 3 types were examined in detail according to their personality traits and life habits. It was found that the mind-body relationship took the primary form in the psychosomatic and neurotic types, while in the organic type it took the secondary form such as distorted life habits. This finding indicated that the distortion in the personality structure and that of life habits were closely interrelated. The authors also discussed the clinical features of chronic pancreatitis from the standpoint of alexithymia. The patients with the organic type were most alexithymic, which were followed by the psychosomatic type. It was learned that alexithymic problems were reflected in the patients' life habits.  相似文献   
46.
BACKGROUND: Correcting Th1/Th2 imbalance with administration of IL-12 before and during antigen challenge holds therapeutic promise in asthma. However, the effects of IL-12 on the established asthmatic responses have not fully been examined. OBJECTIVE: We investigated whether IL-12 administered after antigen challenge could diminish airway hyper-reactivity (AHR) and eosinophilia in mice actively sensitized to ovalbumin. We also have investigated the ability of administered IL-12 to induce IL-18 receptor (IL-18R) expression that may lead possible synergic action of IL-12 with endogenous IL-18. METHODS: C57BL/6 mice immunized to ovalbumin (OVA) by intraperitoneal (i.p.) injection, were challenged three times with an aerosol of OVA every second day for 8 days. Recombinant IL-12 (500 ng) was intravenously administered on a single occasion 1 h after the final challenge of mice. Mice were analysed for effects of IL-12 on AHR, inflammatory cell infiltration and cytokine levels in lung tissue as well as serum immunoglobulin (Ig) E levels. Immunohistochemistry for IL-18R was performed using rat monoclonal antibody specific for murine IL-18Ralpha (IL-1 receptor related protein; IL-1Rrp). RESULTS: An intravenous IL-12 administration diminished AHR, pulmonary eosinophilia and T lymphocyte infiltration, serum IgE, IL-4 and IL-13 in lung tissue. Expression of IL-18R was induced in the mononuclear cells in the lung of mice exposed to OVA. IL-12 administration enhanced the IL-18R expression compared with the control. CONCLUSION: These data indicate that IL-12 can attenuate established antigen-induced AHR and inflammation. In this mechanism it would be interpreted as follows: IL-12 administration in OVA-challenged mice decreased IL-4 production and IgE production thereafter through direct effect on inhibiting the activation of established Th2 cells response and also combined effect with up-regulation of IL-18R expression by inflammatory cells in the lung.  相似文献   
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48.
CD27 is a T cell activation antigen expressed on a majority of peripheral blood T cells. CD27 is also expressed on a subpopulation of human B cells, and it is reported that CD27+ B cells secrete both IgG and IgM. CD70, a ligand for CD27, is expressed on activated T and B cells, suggesting an interaction between T and B cells via CD27/CD70 ligation. Here, we analyze B cell immunoglobulin synthesis using a CD70 transfectant and present functional data showing that B cells secrete large amounts of IgG and IgM as a result of the CD27/CD70 interaction. A flow cytometric analysis showed that CD27 expression was increased and CD70 was expressed on tonsillar and peripheral blood B cells after activation with Staphylococcus aureus Cowan strain (SAC) plus interleukin (IL-2). In addition, the proliferation of B cells was enhanced mildly by the addition of CD70 transfectant, and its proliferation was blocked by anti-CD70 mAb. More importantly, the CD70 transfectant enhanced IgG and IgM production by purified B cells greatly in the presence of SAC plus IL-2. The enhancement was completely blocked by the addition of either anti-CD70 mAb or anti-CD27 mAb. Strongly suggesting that the interaction of CD27 with its ligand, CD70, on B cells plays an important role in B cell growth and differentiation to produce IgG and IgM.  相似文献   
49.
A common amplification target encompassing chromosome region 3q25 to q27 has been identified by comparative genomic hybridization analyses in tumors of the cervix, ovary, endometrium, lung, and head and neck. Because this segment spans at least 30 megabases, we undertook a molecular analysis of copy number to more precisely define the amplification domain. Our Southern blot and fluorescence in situ hybridization results with the use of 17 markers confirmed the presence of low-level 3q amplification events in cervical, ovarian, and variant SCLC tumors. Most of the tumor types studied appeared to have similar, broad amplification domains centered within 3q26.2, suggesting that the same target is being affected in all. The ovarian carcinoma cell line NIH:OVCAR3 had a highly restricted amplification domain spanned by four overlapping YAC clones, suggesting a small target. The region of highest amplification included the gene for the RNA component of telomerase (hTR), supporting it as a potential target. Although the importance of low-level amplification is unknown, the consistent and reproducible nature of this event in a variety of carcinomas suggests that 3q26.2 harbors an oncogene whose low-level amplification has a significant influence on tumor biology.  相似文献   
50.
A humanized monoclonal IgG1 antibody, designated hC4G1, recognizes the fibrinogen receptor glycoprotein (GP)IIb/IIIa on platelets and inhibits platelet aggregation. When the F(ab′)2 fragment of hC4G1 (F(ab′)2 hC4G1) was administered to cynomolgus monkeys, all the monkeys showed inhibition of platelet aggregation ex vivo. Unexpectedly, a significant decrease in platelet count was observed in 5 of 18 monkeys. Antibodies against F(ab′)2 hC4G1 were detected in the plasma of these monkeys by ELISA. Antibody activity in the plasma of these monkeys was significantly correlated with the intensity of platelet decrease (r = 0.84). The natural monkey antibodies to F(ab′)2 hC4G1 were directed against the C-terminal region of F(ab′)2 fragment common to all human and humanized IgG antibodies. Natural homo-reactive antibodies were also detected in human plasma from 15 of 40 healthy volunteers. Specificity was closely similar to that of the monkey antibodies. Affinity-purified human homo-reactive antibodies enhanced phagocytosis of platelets treated with the F(ab′)2 hC4G1. Monkey plasma with high homo-reactive antibody activity was confirmed to decrease platelet count when administered together with F(ab′)2 hC4G1 to a monkey with low antibody activity. These results suggest that F(ab′)2 of humanized and human antibodies causes elimination of the corresponding antigens from the circulation by homo-reactive antibodies.  相似文献   
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