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991.
This study analyzes ten cases of malignancy in a cohort of 183 renal transplant recipients, examining surgical management, postoperative immunosuppressive therapy, and long-term outcome. One of these ten patients, who had malignant lymphoma of the jejunum, died of the neoplasm, but the other nine patients did not show any signs of tumor recurrence after removal. All of these nine patients, except for one who had transplant renal cell carcinoma (RCC), received the same dose of immunosuppressive agents after surgery for the malignant disease. Seven patients were still alive at the time of this report, six of whom had good transplant renal function. The findings of this study indicate that even if immunosuppressive agents predispose to the development of cancer, it is not necessary to reduce their dose after removal of the tumor. Received: April 17, 2000 / Accepted: November 20, 2000  相似文献   
992.
993.
16种支孢随机扩增 DNA多态性研究   总被引:1,自引:0,他引:1  
目的 了解支孢属腐生真菌与致病真菌的基因学特征及二者的关系。方法 采用溴苯提取法提取基因组DNA,以随机扩增DNA多态性法对16种支孢26株菌的DNA指纹图谱作了分析。结果 (1)共选用10个随机引物进行扩增,筛选出2个具有稳定,清晰DNA扩增带型的引物,即引物2:5′-AGGGTCCTCC-3′,引物5:5′-CAGCACCCAC-3′。(2)26株菌DNA带型不完全相同,有一定的种间和种内的遗传变异性,遗传相似性约为37.4%,(3)同种菌具有较高的遗传相似性。(4)部分腐生菌与致病菌位于同一树组中。结论 随机扩增DNA多态性法研究发现支孢属内各种间有一定的遗传相似性。但腐生菌与致病菌的DNA带型性差异。  相似文献   
994.
A technique of combined minimally invasive coronary artery surgery and abdominal aneurysm repair is described. A mini-sternotomy and off-pump coronary artery bypasses to the left descending branch and right coronary arteries are conducted before abdominal aneurysm repair in a simultaneous operation.  相似文献   
995.
Background: It is believed that isoflurane decreases blood pressure predominantly by decreasing systemic vascular resistance with modest myocardial depression. Nevertheless, little information is available regarding the direct action of isoflurane on systemic resistance arteries.

Methods: With use of the isometric force recording method, the action of isoflurane on contractile response to norepinephrine, a neurotransmitter that plays a central role in sympathetic maintenance of vascular tone in vivo, was investigated in isolated rat small mesenteric arteries.

Results: In the endothelium-intact strips, the norepinephrine response was initially enhanced after application of isoflurane (2-5%), but it was subsequently almost normalized to the control level during exposure to isoflurane. However, the norepinephrine response was notably inhibited after washout of isoflurane. In the endothelium-denuded strips, the norepinephrine response was gradually inhibited during exposure to isoflurane (>= 3%), and the inhibition was prolonged after washout of isoflurane. The isoflurane-induced enhancement of norepinephrine response was still observed after inhibitions of the nitric oxide, endothelium-derived hyperpolarizing factor, cyclooxygenase and lipoxygenase pathways, or after blockade of endothelin-1, angiotensin-II, and serotonin receptors; however, it was prevented by superoxide dismutase.  相似文献   

996.
Madder color (MC), a food coloring extracted from roots of Rubia tinctorum L., has been proven to exert carcinogenicity in the rat kidney and liver. Furthermore, it induces DNA adducts in the kidney, liver, and colon. MC is in fact composed of anthraquinones such as lucidin-3- O -primeveroside and alizarin. To clarify which of these might be responsible for the carcinogenicity, a rat medium-term multi-organ carcinogenesis bioassay was performed focusing on the kidney, liver, and colon. Male 6-week-old F344 rats after receiving five different carcinogens were fed a diet containing either 0.008% or 0.04% of alizarin or rubiadin, a metabolite of lucidin-3- O -primeveroside, for 23 weeks. Treatment with 0.04% rubiadin significantly increased atypical renal tubules/hyperplasias and induced renal cell adenomas and carcinomas. Renal cell tumors were also increased with 0.04% alizarin, although at lower incidence than with rubiadin. In addition, glutathione S -transferase placental form-positive liver cell foci and large intestinal dysplasias were significantly increased with 0.04% rubiadin. These results indicate that both rubiadin and alizarin can increase renal preneoplastic lesions, the potential of the latter being weaker. Rubiadin may also target the liver and large intestine, suggesting a major role in madder color-induced carcinogenicity. ( Cancer Sci 2009; 100: 2261–2267)  相似文献   
997.
Constitutively active mutations of epidermal growth factor receptor (EGFR) (delE746_A750) activate downstream signals, such as ERK and Akt, through the phosphorylation of tyrosine residues in the C-terminal region of EGFR. These pathways are thought to be important for cellular sensitivity to EGFR tyrosine kinase inhibitors (TKI). To examine the correlation between phosphorylation of the tyrosine residues in the C-terminal region of EGFR and cellular sensitivity to EGFR TKI, we used wild-type (wt) EGFR, as well as the following constructs: delE746_A750 EGFR; delE746_A750 EGFR with substitution of seven tyrosine residues to phenylalanine in the C-terminal region; and delE746_A750 EGFR with a C-terminal truncation at amino acid 980. These constructs were transfected stably into HEK293 cells and designated HEK293/Wt, HEK293/D, HEK293/D7F, and HEK293/D-Tr, respectively. The HEK293/D cells were found to be 100-fold more sensitive to EGFR TKI (AG1478) than HEK293/Wt. Surprisingly, the HEK293/D7F and HEK293/D-Tr cells, transfected with EGFR lacking the C-terminal autophosphorylation sites, retained high sensitivity to EGFR TKI. In these three high-sensitivity cells, the ERK pathway was activated without ligand stimulation, which was inhibited by EGFR TKI. In addition, although EGFR in the HEK293/D7F and HEK293/D-Tr cells lacked significant tyrosine residues for EGFR signal transduction, phosphorylation of Src homology and collagen homology (Shc) was spontaneously activated in these cells. Our results indicate that tyrosine residues in the C-terminal region of EGFR are not required for cellular sensitivity to EGFR TKI, and that an as-yet-unknown signaling pathway of EGFR may exist that is independent of the C-terminal region of EGFR. ( Cancer Sci 2009; 100: 552–557)  相似文献   
998.
The case was a 40-year-old female. She visited a local doctor with a chief complaint of right side abdominal pain. A right kidney tumor measuring 10 cm in diameter was observed in an abdominal Computed Tomography (CT) scan. Based on the CT image, the possibility of angiomiolipoma (AML) could not be ruled out, but a high maximum standardized uptake value (SUVmax) of 7.8 was observed in a Positron Emission Tomography CT (PET-CT) scan and there was a possibility of malignancy. We therefore performed a transperitoneal right radial nephrectomy. Although adhesion of the tumor to the duodenum and the inferior vena cava was observed, it was possible to perform an excision. The tumor accounted for a large proportion of the excised kidney; the surrounding areas had taken on a cyst-like structure, and the interior comprised grayish brittle tissue exhibiting solid growth. Histologically, gland-like and cyst-like structures composed of cylindrical cuboidal cells and mainly characterized by the solid growth of short fusiform-shaped and oval-shaped basophilic cells were observed, and we believed it was a synovial sarcoma. There were no malignant findings in the adrenal gland. There have been approximately 30 reported cases around the world of synovial sarcoma that developed in the kidney, and we herein report this case with bibliographic considerations.Key Words: Synovial sarcoma, Renal tumor, Renal mass, PET-CT, SYT-SSX  相似文献   
999.
There are many reports of second allogeneic stem cell transplantation (allo-SCT) using cord blood (CB) for graft failure after initial allo-SCT. However, the efficacy of second allo-SCT using CB for patients with leukemia relapsed after initial allo-SCT is unknown. We report the results of second allo-SCT using CB in seven adult patients with leukemia relapsed after initial allo-SCT. All patients received a myeloablative conditioning regimen including oral busulfan 16 mg/kg, intravenously fludarabine 100mg/m(2) and cyclophosphamide 120 mg/kg. All but one patient had myeloid reconstitution and four patients remain alive at between 4 and 40 months after second SCT. We conclude that second myeloablative allo-SCT using CB may be feasible in selected patients with the relatively younger age, less organ damage and longer time interval between first and second allo-SCT.  相似文献   
1000.
Epidermal growth factor receptor (EGFR) mutations play substantial roles in genesis and proliferation of non-small-cell lung cancers (NSCLCs). We recently found that reproductive factors have a substantial impact on risk of development of NSCLCs featuring such EGFR mutations. Therefore, we explored the influence of dietary habits on NSCLC risk with reference to the EGFR mutational status. We conducted a case-control study using 353 patients with NSCLCs (122 EGFR mutated and 231 EGFR wild-type) and 1765 age-sex matched non-cancer control subjects. Dietary exposure was based on a semiquantitative food frequency questionnaire and impact of major food items, like meats, seafoods, vegetables and soybean products was assessed by multivariate logistic regression. Soybean products demonstrated a protective association with EGFR mutated, but not EGFR wild-type NSCLCs, with multivariate-adjusted odds ratios and 95% confidence intervals for the 2nd and 3rd tertile of soybean product consumption of 0.79 (0.50–1.27) and 0.56 (0.34–0.93) relative to those in the lowest tertile (trend P  = 0.023). In conclusion, soy consumption may exert a protective association against the development of NSCLCs with EGFR mutations, providing possible insights into mechanisms of their genesis. ( Cancer Sci 2008; 99: 1202–1208)  相似文献   
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