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51.
Three common branches of the celiac trunk are the left gastric artery, the splenic artery and the common hepatic artery. The variation of the three branches of the celiac trunk has an importance for the arterial supply to the digestive organs of the upper abdomen. In this study, we present three cases of the gastrosplenic and the hepatomesenteric trunks in Japanese cadavers. Especially, in Case 1, the left inferior phrenic artery arose from the gastrosplenic trunk and the left hepatic artery arose from the left gastric artery. In Cases 2 and 3, the common hepatic artery penetrated the pancreatic parenchyma before reaching liver. In Case 3, the right hepatic artery arose from the hepatomesenteric trunk.  相似文献   
52.
The purpose of this study was to examine, by positron emission tomography (PET), the distribution of [18F]fluoro-deoxy-glucose ([18F]FDG) uptake by human muscles during 35?min of running. Thirteen healthy male subjects were studied, seven of whom participated in the exercise study. Running intensity was kept constant such that the subjects' heart rates were maintained at between 140 and 150?beats per minute. [18F]FDG [62.9 (14.8)?MBq, mean (SD)] was injected after 15?min of running. PET imaging was started immediately after the running ended. The ratio of [18F]FDG uptake by muscles in runners to that in control subjects (r-c ratio) varied from three to six for the muscles of the foot and leg below the knee joint. The r-c ratio of the medial head of the gastrocnemius (MG) was higher than that of its lateral head (LG). The r-c ratio of the rectus femoris (RF) was lower than that of the other three muscles of the quadriceps femoris (QF). The r-c ratio of inactive muscles located above the waist was approximately 0.7. These results suggest that, during the moderate running of this study: (1) glucose uptake by muscles of the foot and leg below the knee joint clearly increases, (2) the r-c ratio differs significantly among the skeletal muscles, which act synergistically, and (3) glucose uptake by inactive skeletal muscles decreases.  相似文献   
53.
To assess muscle metabolism and inorganic phosphate (Pi) peak splitting during exercise, 31-phosphorus nuclear magnetic resonance spectroscopy was performed during ramp incremental and submaximal step exercise with and without circulatory occlusion. Seven healthy men performed calf flexion in a superconducting magnet. There was no Pi splitting during ramp incremental exercise with the circulation present and phosphocreatine (PCr) decreased linearly by 0.07 (SEM 0.01) mmol?·?l?1?·?s?1, while exercise with the circulation occluded caused the Pi peak to split into a high and a low pH peak. The rate of PCr decrease during exercise with the circulation occluded was 0.15 (SEM 0.03) mmol?·?l?1?·?s?1 which with the efficiency of the adenosine 5′-triphosphate (ATP) hydrolysis reaction corresponded well to the mechanical energy. Both with and without occlusion of the circulation PCr decreased with some time lag which may reflect the consumption of residual oxygen. In submaximal step exercise PCr decreased exponentially at the onset of exercise with the circulation open whereas it decreased linearly by 0.15?mmol?·?l?1?·?s?1 when the circulation was occluded. After exercise, occlusion of the circulation was maintained for 1 min more and there was no PCr resynthesis. It is suggested that ATP synthesis was limited by the availability of oxygen.  相似文献   
54.
The human dopamine D4 receptor (DRD4) is of major interest in molecular studies of schizophrenia and personality traits. We examined the association of schizophrenia and polymorphisms in the upstream region of the DRD4 gene (−768G>A in the negative modulator region; −521C>T, −376C>T, and −291C>T in the cell type-specific promoter region; and −616C>G between the two regions) in 208 schizophrenic patients and 210 normal controls. No significant difference in genotype and allele frequencies was observed between the two groups, indicating that these polymorphisms do not make a major contribution to the pathogenesis of schizophrenia. We also studied the association of polymorphisms in the upstream region and a 48-bp repeat polymorphism in exon III of the DRD4 gene with personality traits in 173 Japanese individuals who completed the temperament and character inventory (TCI). The −768G>A polymorphism was significantly associated with reward dependence (P = 0.044), while no significant association was observed between novelty seeking and polymorphisms in the upstream region or the exon III repeat polymorphism of the DRD4 gene. Received: August 28, 2000 / Accepted: October 25, 2000  相似文献   
55.
The histologic characteristics of a case of epidermoid cyst formation with an epithelioid cell granuloma that developed in intrapancreatic accessory spleen were investigated, with the aim of clarifying its origin as well as etiologic factors. The patient, a 48-year-old male, was found to have a cystic lesion in the tail of the pancreas and renal cell carcinoma (clear cell carcinoma) during a medical check up. The pancreatic mass appeared to be a so-called "mucinous tumor" on imaging, and combined resection of the body and tail of the pancreas and the spleen was performed together with a left nephrectomy. The lesion in the tail of the pancreas was then demonstrated to have accessory splenic tissue with cyst formation in its central region. The cystic wall was covered with stratified squamous epithelium and ductal epithelium with squamous metaplasia, and pancreatic islet cells were evident at various sites within the accessory spleen. Formation of epithelioid cell granuloma tissue was observed around the cysts. The epithelium of the cyst was positive for CA19-9 and negative for antibodies against mesothelial cells, whereas the pancreatic island cells were positive for insulin. These results suggested that cystic epithelium in the accessory spleen could be derived from pancreatic duct epithelium. Frequent recurrence of chronic inflammation and epitheloid cell granuloma formation may have resulted from an aberration of the ectopic remaining pancreatic tissue in the spleen.  相似文献   
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A simple system has been developed-for the prolonged infusion of an iced solution of prostacyclin (PGI2). In a 24 h period at pH 10, there is a theoretical loss in activity of 6%, while a 5 h infusion leads to a 2% reduction in activity. The stability of the cooling system was demonstrated in six dog experiments where mean arterial pressure (MAP) was reduced to 58±3.8 Torr (x±SEM) over a 5 h period of infusing 500 ng/kg/min. In a saline medium, at 3°C, a 5 h PGI2 infusion led to a stable reduction in MAP, whereas, at a temperature of 24°C, a 70 loss of infusate activity was noted. Supported in part by The National Institute of Health, Grant No. GM24891-04; The U.S. Army Medical Research and Development Command, Contract No. DAMD17-78-C-8026; The Brigham Surgical Group, Inc., and The Trauma Research Foundation.  相似文献   
60.
Cytoplasmic concentrations of Ca2+ ([Ca2+]i) and Mg2+ ([Mg2+]i) were measured with fluorescent indicators in CCL39 cells, a cell line established from Chinese hamster lung fibroblasts, transfected with complementary deoxyribonucleic acid (cDNA) of the Na+-Ca2+ exchanger isolated either from canine heart (NCX1) or from rat brain (NCX3). Raising extracellular [Mg2+] to 10 mM increased Mg2+ influx and the resultant change in [Mg2+]i (delta[Mg2+]i) was monitored with furaptra under Ca2+-free conditions. In control (vector-transfected) cells, delta[Mg2+]i at 45 min was similar with or without extracellular Na+ (130 mM or 0 mM) and when [Na+]i was raised by 1 mM ouabain treatment. delta[Mg2+]i in NCX1-transfected cells was attenuated significantly in the presence of 130 mM Na+, but became comparable to (or slightly larger than) that in control cells on either removal of extracellular Na+ or treatment with 1 mM ouabain. Cells expressing NCX3 showed an intermediate dependence of delta[Mg2+]i on Na+, probably reflecting a lower degree of expression of the exchanger protein. Extracellular Na+-dependent changes in [Ca2+]i (measured with fura-2 in the presence of extracellular Ca2+ and 10 microM ionomycin, a Ca2+ ionophore) were minimal in control cells, marked in the NCX1-transfected cells and intermediate in the NCX3-transfected cells. These results suggest that the Na+-Ca2+ exchanger (either NCX1 or NCX3) can transport Mg2+ and may play a role in the extrusion of magnesium from cells.  相似文献   
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