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71.
72.
A 69-year-old woman with a 6-year history of rheumatoid arthritis treated solely with an orally administered NSAID had slowly progressing persistent mild abdominal pain and diarrhea, accompanied with marked sing of inflammation as well as hypoproteinemia due to protein-losing gastroenteropathy. Examinations of the large intestine revealed variously shaped ulcerative lesions, centered around the left hemicolon, as well as luminal narrowing. The course of the disease and the shape of the lesions strongly suggested involvement of rheumatoid vasculitis; oral administration of prednisolone was effective.  相似文献   
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74.

Purpose  

The aim of this study was to investigate the antitumor efficacy of treatment, identify prognostic factors, and construct a prognostic index in patients with hepatocellular carcinoma treated by transcatheter arterial infusion chemotherapy (TAI) using cisplatin suspended in lipiodol.  相似文献   
75.
Clostridium perfringens iota-toxin is a binary toxin composed of an enzyme component (Ia) and a binding component (Ib). Each component alone lacks toxic activity, but together they produce cytotoxic effects. We examined the cytotoxicity of iota-toxin Ib in eight cell lines. A431 and A549 cells were susceptible to Ib, but MDCK, Vero, CHO, Caco-2, HT-29, and DLD-1 cells were not. Ib bound and formed oligomers in the membranes of A431 and MDCK cells. However, Ib entered MDCK cells but not A431 cells, suggesting that uptake is essential for cellular survival. Ib also induced cell swelling and the rapid depletion of cellular ATP in A431 and A549 cells but not the insensitive cell lines. In A431 cells, Ib binds and oligomerizes mainly in nonlipid rafts in the membranes. Disruption of lipid rafts by methyl-β-cyclodextrin did not impair ATP depletion or cell death caused by Ib. Ib induced permeabilization by propidium iodide without DNA fragmentation in A431 cells. Ultrastructural studies revealed that A431 cells undergo necrosis after treatment with Ib. Ib caused a disruption of mitochondrial permeability and the release of cytochrome c. Staining with active-form-specific antibodies showed that the proapoptotic Bcl-2-family proteins Bax and Bak were activated and colocalized with mitochondria in Ib-treated A431 cells. We demonstrate that Ib by itself produces cytotoxic activity through necrosis.  相似文献   
76.
DMY gene induces male development in genetically female (XX) medaka fish   总被引:3,自引:0,他引:3  
Although the sex-determining gene SRY/Sry has been identified in mammals, homologues and genes that have a similar function have yet to be identified in nonmammalian vertebrates. Recently, DMY (the DM-domain gene on the Y chromosome) was cloned from the sex-determining region on the Y chromosome of the teleost fish medaka (Oryzias latipes). DMY has been shown to be required for the normal development of male individuals. In this study, we show that a 117-kb genomic DNA fragment that carries DMY is able to induce testis differentiation and subsequent male development in XX (genetically female) medaka. In addition, overexpression of DMY cDNA under the control of the CMV promoter also caused XX sex reversal. These results demonstrate that DMY is sufficient for male development in medaka and suggest that the functional difference between the X and Y chromosomes in medaka is a single gene. Our data indicate that DMY is an additional sex-determining gene in vertebrates.  相似文献   
77.
Cytochrome P450c17 is the single enzyme that mediates the 17 alpha-hydroxylase and 17, 20 lyase activities during the biosynthesis of steroid hormones in the gonads and adrenal gland. However, the mechanism underlying its dual action continues to be a controversy in the field of steroidogenesis in fish. In an attempt to resolve this issue, we identified a novel type of P450c17 (P450c17-II) by an in silico analysis from the genomes of six fish species. We cloned P450c17-II from tilapia and medaka, and comparison with the conventional P450c17-I revealed that they differ in gene structure and enzymatic activity. Enzymatic assays by thin-layer chromatography revealed that P450c17-II possesses only the 17 alpha-hydroxylase activity without any 17, 20 lyase activity, unlike P450c17-I, which has both these activities. In testis, both P450c17-I and -II express in the interstitial cells. Remarkable differences, revealed by in situ hybridization, in the expression patterns of the P450c17-I and -II in the ovary and head kidney of tilapia during various stages of development strongly suggest that P450c17-I is responsible for the synthesis of estradiol-17beta in the ovary, whereas P450c17-II is required for the production of C21 steroids such as cortisol in the head kidney. More interestingly, a temporally controlled switching is observable in the expression of these two genes during the steroidogenic shift from estradiol-17beta to the C21 steroid, 17 alpha, 20 beta-dihydroxy-4-pregnen-3-one (maturation-inducing hormone of fish oocytes) in the fish ovary, revealing a role for P450c17-II in the production of hormones that induce oocyte maturation in fish.  相似文献   
78.
79.
A 69-year-old male was operated on sigmoidectomy for sigmoid colon cancer (SS, N2, H0, P0, M0, stage IIIb) 7 years ago. Two years later, he was diagnosed for rectal cancer and bilateral lung metastases by TBLB. We performed Mile's operation, and the rectal focus was pathologically diagnosed with a recurrence of sigmoid colon cancer. After surgery, chemotherapy with FOLFOX was started for bilateral lung metastases, resulting in CR during the 22 months. But bilateral lung metastases were exacerbated, and then we administered several other chemotherapies. Five years have passed since chemotherapy started, although the focuses tended to progress. Right now, he has been a chemotherapy outpatient for last 5 years.  相似文献   
80.
A 37-year-old female, who had undergone a low anterior resection for lower rectal cancer, had been received chemotherapy (FOLFOX4, FOLFIRI) for 2 years because of right ovarian metastasis occurred and removed 9 months after the first operation. One month after 2 years of continued chemotherapy, progressive metastases happened to occur successively (rt lunge, left ovarium, liver, para-aortic lymphonode, Virchow lymphonode and bone). Right upper lobe pnemonectomy was performed first, then, peritonectomy, total hysterectomy with left oophorectomy and a partial resection of the small bowel were done. IRIS, as postoperative chemotherapy, performed with hepatic arterial infusion (HAI) of CPT-11 and 5- FU resulted in getting a minimal response for about 10 months. Because of the hepatic arterial thrombosis at 10 months after the previous operation, we could not continue HAI with systemic chemotherapy, that was resulted in the progresion of mutiple metastases, and that the patient died 62 months after the first surgery. Immunohistochemical analyses with MIB-1 stainning of four surgical specimens revealed 80% positive cells in the cancerous tissues.  相似文献   
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