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This study was designed to examine the differences in the effect of an iron-deficient diet on iron metabolism in Fischer-344 (FC), Sprague-Dawley (SD) and Wistar (WT) rats based on hemoglobin (Hb), hematocrit (Hct), serum iron levels, growth rate and organ weight. Hb concentration was higher in FC rats (14 mg/100 mL) on the initial day than in SD (10) and WT (10) rats. Although the Hb level was significantly decreased in FC rats fed an iron-deficient (ID, 8 mg/kg) diet for 33 d compared to the FC rats fed an iron-adequate (IA, 50 mg/kg) diet, the relative concentration of Hb was high in FC rats fed the ID diet as compared to the SD and WT rats fed the same diet. A similar relationship was detected between Hct and serum iron concentrations. Although serum triglycerides (TG) were significantly increased in each rat strain fed the ID diet as compared to the IA diet, the percentage of the value for the IA diet was lowest in FC rats (119%) fed the ID diet as compared to the SD (328) and WT (394) rats fed the same diet. Retroperitoneal fat pad was decreased in FC, SD and WT rats fed the ID diet as compared to the IA diet. SD rats were particularly sensitive to the reduction of retroperitoneal fat pad. The results suggested that rat strains responded differently to dietary iron inadequacy, and that FC rats were less sensitive to an iron-deficient diet as compared to the SD and WT rats.  相似文献   
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Purpose: Membrane cofactor protein (MCP), CD46, whose primary function is to protect host cells from homologous complement, has been presumed to serve as a sperm adhesion molecule for oocytes. The purpose of this study was to clarify the relationship between the properties of MCP expressed on epididymal sperm and their fertilizing ability in a recently developed strategy for assisted reproduction. Methods: We collected ejaculated sperm from normal subjects and epididymal sperm from vasectomized subjects and patients with congenital absence of the vas deferens. Western blotting and cofactor activity assay were performed to investigated the structural and functional properties of MCP. Results: Epididymal spermatozoa which showed a reduced fertilizing ability tended to react poorly with antibodies against MCP and also showed low cofactor activity, indicating weak complement regulatory activity compared to that of ejaculated spermatozoa. Conclusions: MCP is sufficiently expressed in ejaculated sperm in men with a normally developed epididymis but is diminished in epididymal sperm from men with congenital or acquired obstruction of the vas deferens.  相似文献   
65.

Purpose

The effects of prolonged sevoflurane anaesthesia on insulin sensitivity were investigated by two successive intravenous glucose tolerance tests (IVGTT) in eight patients who underwent prolonged surgery.

Methods

The first IVGTT was administered (25 g glucose as 20% dextrose in water iv) over two minutes 35 min after initiation of surgery. Arterial blood samples were obtained at 0, 5, 10, 30, 60, and 120 min after glucose administration for blood glucose and plasma insulin determination. A second IVGTT was performed six hours following the initiation of surgery.

Results

The disappearance rate of glucose (k-value) for the first IVGTT was 0.887 ± 0.436 (mean ± SD) % · min?1, and 0.784 ± 0.289 for the second IVGTT. Both k-values are lower than the normal value. The maximum insulin response to glucose (ΔIRI · ΔBS?1) of the second IVGTT was lower than the first IVGTT (0.124 ± 0.092 vs 0.071 ± 0.056, P < 0.05). The total insulin output of the first IVGTT was higher than the second IVGTT (1,161 ± 830 vs 568 ± 389 μU · min · ml?1, P < 0.05).

Conclusion

Glucose intolerance is enhanced by diminished insulin output in response to blood glucose elevation during prolonged anaesthesia and surgery.  相似文献   
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Background Deletions involving chromosome 9p21, on which the tumor suppressor genep16/MTS1 is located, have been noted in esophageal cancer. We investigated the relationship between the deletion of chromosome 9p21–22 and the clinical features of esophageal cancer. Methods We examined the loss of heterozygosity (LOH) on chromosome 9p21–22 in 56 esophageal cancers using polymerase chain reaction (PCR) analysis and 2 microsatellite markers (RPS6 and IFNA). Results In 18 out of 50 informative cases (36%), LOH had occurred at 1 or 2 loci on chromosome 9p21–22. We found no relationship between LOH on chromosome 9p21–22 and patient sex, age tumor length, location, histologic differentiation, depth of tumor invasion, the extent of lymph node metastasis, histologic stage, or curability. Among 35 patients without an absolute noncurative resection, the mean survival of 11 patients with LOH on chromosome 9p21–22 was 19.3 months, compared with 42.3 months for 24 patients with a normal allele; thus, the survival rate of those with LOH was significantly lower than that of patients without LOH on chromosome 9p21–22 (log-rank test;P=0.03). Conclusion These data suggest that LOH on chromosome 9p21–22, on which the cell-cycle regulatorp16/MTS1 gene is located, may be related to cancer development, and probably can serve as a clinical marker for evaluating a patient's prognosis.  相似文献   
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Tumor lysis syndrome is a rare complication of nonhematologic malignancies that results from massive necrosis of neoplastic cells after chemotherapy. This syndrome consists of life-threatening metabolic derangements, including severe hyperphosphatemia, hyperkalemia, hyperuricemia, and hypocalcemia, and may result in renal failure and death if not recognized early and treated appropriately. We report a case of tumor lysis syndrome after induction chemotherapy in a patient with widely metastatic smallcell lung cancer. This case emphasizes the importance of awareness and early treatment of this syndrome.  相似文献   
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Liver metastasis is the gravest prognostic factor in colorectal cancer. To identify a reliable indicator for liver metastasis, we evaluated macroscopic features and seven established histopathological findings at the cut section containing the deepest penetration using univariate and multivariate analyses in 417 colorectal cancers. Macroscopic features were divided into two types, streak type and non-streak type, according to the presence or absence of white streak(s) at the advancing margin of tumor invasion. Streak type was observed in 109 patients (26%). The frequency of liver metastasis in streak type tumors (56%) was significantly higher than that in non-streak type tumors (13%) (p < 0.001). The white streak corresponded histologically with cancer cells showing focal dedifferentiation with marked stromal and perivascular fibrosis extending towards the serosa or adventitia. In 343 curatively treated patients, univariate analysis showed that recurrent liver metastasis was significantly associated with macroscopic features, venous invasion, focal dedifferentiation and lymph node metastasis. Multivariate analysis disclosed that macroscopic features and lymph node metastasis were independent indicators of liver metastasis. These macroscopic features, corresponding histologically to stromal behavior against invading cancer cells, are a simple and useful indicator of liver metastasis of colorectal cancer.   相似文献   
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