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101.
A new triene aldehyde, (2E,6Z,9Z)-2-methyl-2,6,9-icosatrienal (1), was isolated from a MeOH extract of the Okinawan marine sponge Leucetta microraphis. The structure of 1 was determined by spectroscopic analysis. Three imidazole alkaloids, leucettamine B, preclathridine A, and (9E)-clathridine 9-N-(2-sulfoethyl)imine, were also obtained and identified. Compound 1 showed moderate growth-inhibitory activity toward HeLa S3 cells.  相似文献   
102.
HARA-B cells were established from the bone lesion in nude mice formed after an intracardiac inoculation of the human lung cancer-derived cells (HARA), and production of IL-8 in HARA-B cells was decreased as compared to that in the parental HARA cells. This suggests a possible relationship between IL-8 production and bone metastasis. Thus, we examined the effect of IL-8 on bone metastasis using HARA-B cells transfected with experimental (IL-8-cDNA) and/or control plasmid in the experimental bone metastasis model in nude mice. Growth rates of both cells in vitro were similar. Control cells developed radiologically detectable bone metastases in 50% of nude mice tested, whereas experimental cells did not develop bone metastases. Osteoclastic bone resorption is an important step in the process of bone metastasis, and IL-8 possesses an inhibitory effect on osteoclastic bone resorption. These results suggest that IL-8 suppresses bone metastasis, which might be attributed to the inhibitory effect of IL-8 on osteoclastic bone resorption.  相似文献   
103.
OBJECTIVE: We compared the effects of tactile interference to the forearm on magnetic responses evoked by electric stimulation of the little finger (D5) and the thumb (D1). METHODS: Electric stimulation was delivered to D5 or D1 individually. In each stimulus session, magnetic recordings were conducted with or without concurrent tactile interference to the radial side of the anterior forearm. RESULTS: With forearm interference, the amplitude of the primary response (N20m) following D5 stimulation was reduced to 90.7% of the control value without interference, while that following D1 stimulation was not affected (100.7%). CONCLUSIONS: In human somatosensory area 3b, the representation of the forearm is immediately adjacent to that of the D5, and distant from that of the D1. Thus, the result suggests that the tactile interference effect on N20m depends on the cortical distance between electrically and mechanically activated 3b areas. SIGNIFICANCE: Intrinsic synaptic connections between the 3b hand representation and its surroundings have been hypothesized as a neural basis for plastic changes of the human brain, such as a phantom hand phenomenon. The present finding implies that these connections may play some physiological roles even in normal adult humans.  相似文献   
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Organ transplant recipients are generally considered to be at greater risk for developing malignant disorders because of prolonged immunosuppression for organ grafting, but acute leukemia is a rare complication after organ transplantation (0.2 - 2.5%). We encountered two girls with acute promyelocytic leukemia (APL) after living donor partial orthotopic liver transplantation. In one patient, APL developed 21 months after liver transplantation for ornithine transcarbamylase deficiency. She had been administered tacrolimus for prophylaxis of graft-versus-host reaction. In the other patient, APL was diagnosed 46 months after liver transplantation for congenital biliary atresia. Both patients were successfully treated by chemotherapy including all-trans retinoic acid (ATRA), and after reaching complete remission, they have subsequently been in continuous remission. Although leukemia after liver transplantation is generally thought of as a rare complication, increases in survival rate following liver transplantation is likely to lead to more such cases, and documentation of these cases is therefore of importance.  相似文献   
106.
Most smokers do not plan to quit in the next 6 months. The authors previously demonstrated that percentile schedules shape lower breath carbon monoxide (BCO) levels in smokers trying to quit (R. J. Lamb, A. R. Morral, K. C. Kirby, M. Y. Iguchi, & G. Galbicka, 2004). In that study, the authors set reinforcement criteria based on the 9 most recent samples. In this study, the authors examined whether a more responsive procedure using the 4 most recent samples is more effective in smokers not trying to quit. Following institution of the contingencies in both groups, BCO levels were substantially reduced, and readiness to quit and cessation self-efficacy increased. However, more individuals in the 4-sample window group achieved a BCO level below 4 ppm, indicating recent abstinence. These individuals did so more rapidly and for a greater number of visits.  相似文献   
107.
Rationale The role of the hippocampal dopaminergic system in mnemonic function has not been clarified yet. Objective We previously reported that the dopamine D2 receptor (D2R) is involved in the regulation of acethylcholin (ACh) release in the hippocampus. In this study, we further investigated ACh–dopamine (DA) interaction in the hippocampus and its involvement in mnemonic function. Methods For experiment 1, rats fed with Cholin (Ch)-deficient chow were used. We examined the effects of D2R antagonist, raclopride, on cognitive performance using a passive avoidance task. We further carried out in vivo microdialysis to assess the effect of infusion of D2R agonist, quinpirole, into the ventral hippocampus on its capacity to release ACh. For experiment 2, rats fed with normal chow were used. The performance of a radial arm maze task was assessed to examine the effects of hippocampal injection of D2R agonist, quinpirole, on memory impairment induced by scopolamine, a muscarinic ACh antagonist. Results In experiment 1, rats fed with Ch-deficient chow showed impaired performances indicated by prolonged latency on retention trials of a passive avoidance task following the hippocampal injection of D2R antagonist, and showed reduced capacity to release ACh following the injection of D2R agonist compared with rats fed with normal chow. In experiment 2, memory impairment induced by the intraperitoneal injection of scopolamine was ameliorated by the injection of D2R agonist into the ventral hippocampus. Conclusion These results indicate the possible involvement of hippocampal ACh–DA interaction in mnemonic processing.  相似文献   
108.
Parasite eggs found in organic remains collected from medieval structures in Raversijde (medieval name: Walraversijde), a village on the northern coast of Belgium, are discussed. The eggs were identified as Ascaris lumbricoides and Trichuris trichiura, both human parasites. Species identification allowed elucidating the origin of the organic sediments and the structures, in this case latrines used by humans. Capillaria sp. and free-living nematode larvae were also found in the latrine. Although neither parasite burden nor prevalence rates could be measured, the abundance of human intestinal parasite eggs indicated a high infection rate in the village residents, reflecting very poor sanitation.  相似文献   
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