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1.
The surgical approach to relief of mitral stenosis in children is still a controversial problem. We describe our experience with four severely symptomatic children in whom a valved conduit from the left atrium to the left ventricle was successfully used to bypass a hypoplastic systemic atrioventricular valve. A left atrial-left ventricular extracardiac conduit was implanted in these patients with a hypoplastic mitral anulus and an adequate left ventricular chamber. There were no early or late deaths. Postoperative cardiac catheterization performed in all patients 1 month after the operation showed reduced size of the left atrium, a reduction of the left atrial-left ventricular gradient from a mean of 14 mm Hg to a mean of 5 mm Hg, and an increase of the left atrial outlet from a mean diameter of 10.7 mm to 28.7 mm (including the diameter of the native mitral valve plus the internal diameter of the valved conduit). The application of this unconventional operation in children with congenital or acquired stenosis of the systemic atrioventricular valve should be considered when the mitral valve obstruction cannot be relieved by conventional valve repair or replacement. Furthermore, the left atrial-left ventricular conduit does not preclude future alternative surgical options.  相似文献   
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In the course of a phase I trial, in which recombinant IL-2 (rIL-2) was infused intraperitoneally (i.p.) in patients with peritoneal carcinomatosis, we evaluated the effect on "tumor-associated lymphocytes" (TAL) isolated from the ascitic fluid. No major changes in the percentages of cells expressing the CD3, CD4, CD8, Leu-7, OKM1 and WT-31 antigens were detected either in TAL or in peripheral blood lymphocytes (PBL) after 7 days of rIL-2 infusion. In contrast the percentages of TAL (but not PBL) expressing surface IL-2 receptor (Tac), or LAK-1 antigen were sharply increased. Analysis of cytolytic functions showed a potentiation of the lytic activity against natural-killer (NK) sensitive K562 target cells and the de novo appearance of lytic activity against fresh melanoma cells. In one patient IFN-gamma was detected in the ascitic fluid following rIL-2 infusion. T-cell clones derived from the patient were analyzed for the IFN-gamma production. While only approximately 40% of PB-derived control clones produced medium to low amounts of IFN-gamma, all of the TAL-derived clones produced medium to high amounts of the lymphokine.  相似文献   
3.
Isothiocyanates (ITCs) are commonly found in cruciferous vegetables. A variety of biological activities have been ascribed to ITCs, such as inhibition of cytochrome P450 enzymes and induction of phase II enzymes in animal models. ITCs are also able to block cell-cycle progression and induce apoptosis in human cancer cells in vitro. In this study, we evaluated the ability of the ITC sulforaphane to protect cultured human lymphocytes from micronucleus (MN) induction by four different mutagens: ethyl methanesulfonate (EMS), vincristrine (VIN), H(2)O(2) and mitomycin C (MMC). To understand the mechanisms of action of sulforaphane, the cultures were treated with the compound before, during and after treatment with the mutagens; in addition, the cultures were evaluated for the induction of apoptosis. Up to 10 microM, sulforaphane was non-genotoxic by itself, while 30 microM sulforaphane reduced the replicative index of the cells by more than 60%. Moreover, 1-10 microM sulforaphane reduced the MN frequency induced by EMS, VIN, H(2)O(2) and MMC in at least one of the treatment protocols; it had no effect on H(2)O(2)-MN induction in the post-treatment protocol, and it increased MN induction by MMC in the pre-treatment protocol. Apoptosis was produced in the cultures treated with sulforaphane alone. The fraction of apoptotic cells was increased after co- or post-treatment with sulforaphane and EMS and MMC, suggesting that sulforaphane-mediated apoptosis may remove highly damaged cells induced by these agents. Other mechanisms are involved in the anti-genotoxic activity of sulforaphane against VIN and H(2)O(2). Taken together, our findings indicate that under certain conditions sulforaphane possesses anti-genotoxic activity in vitro and that further studies are warranted to characterize this property in vivo.  相似文献   
4.
A case of somatostatin-producing pancreatic tumor associated with severe insulindependent diabetes mellitus and ketoacidotic coma is reported. The tumor, a 10-cm expansile mass arising from the pancreatic tail of a 70-yr-old woman, was first detected by ultrasonography, performed because of abdominal pain, and subsequently confirmed by computed tomography and fine-needle tumor aspiration. Pathologic investigation showed a predominatly solid-trabecular structure with scattered microacini and psammomatous bodies. A large proportion of tumor cells expressed somatostatin and/or calcitonin. Following resection of the primary tumor and three peripancreatic lymph nodes with metastases, the patient recovered rapidly from her diabetic syndrome and remained in substantially good health during a subsequent 8-yr follow-up period, without evidence of tumor recurrence.  相似文献   
5.
The existence of distinct tubulins in microtubules forming the sperm axoneme has been demonstrated in various species, whereas little is known about the distribution of tubulin variants in insect spermatozoa. In the present study, a panel of specific antibodies has been used to investigate the presence and localization of tubulin isotypes and post-translationally modified tubulins in the spermatozoon of the stick insect Bacillus rossius. Indirect immunofluorescence and immunogold staining showed differences in labelling in the mature sperm and that the tubulin epitopes localized differentially in the axoneme. In particular, the tyrosinated alpha-tubulin mainly occurs on doublets. These results provide an insight into the molecular composition of the microtubules forming the sperm axoneme of B. rossius and suggest that the structural specificity could reflect distinct functional roles within axonemal microtubules.  相似文献   
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INTRODUCTION: Infection with hepatitis C virus genotype 1b (HCV1b) is known to be a predictive factor of poor response to both interferon-alpha (IFN alpha) alone and IFN alpha plus ribavirin combination therapy.STUDY DESIGN, PATIENTS AND METHODS: This randomised study evaluated the efficacy and safety of daily IFN alpha administration versus the combination of IFN alpha plus ribavirin in treatment-naive patients infected with chronic HCV1b. Sixty-two patients were randomised to receive either human leucocyte IFN alpha 6MU three times weekly for 12 months plus ribavirin 15 mg/kg/day for the first 6 months (group A: 29 patients), or human leucocyte IFN alpha 3MU daily for 12 months (group B: 33 patients). Response was evaluated by monitoring serum alanine aminotransferase (ALT) and HCV-RNA levels during treatment and follow-up (12 months). RESULT AND CONCLUSION: Both treatment schedules were relatively well tolerated. Normal ALT levels and negative serum HCV-RNA were observed in 16 of 29 patients (55%) of group A and in 18 of 33 patients (54.5%) of group B at the end of treatment, as well as in 10 of 29 patients (34.5%) of group A and in 12 of 33 patients (36%) of group B at the end of the follow-up. There was no significant difference between the response rates obtained with the two regimens. In naive patients with chronic HCV1b infection, the efficacy of daily administration with IFN alpha is similar to that of IFN alpha plus ribavirin administered three times a week.  相似文献   
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A total of 1,394 sandflies were collected in the domestic resting sites of Ouagadougou areas and in two villages of the East region of Burkina Faso using pyrethrum spray catch, oiled papers and miniature CDC light traps during the rainy season in 1984 and 1985. Thirteen species were identified, one belonging to the genus Phlebotomus and the others to the genus Sergentomyia. S. antennata (34.94%), S. bedfordi (16.64%), S. clydei (14.42%), S. schwetzi (13.20%), P. duboscqi (8.46%), S. adleri (7.03%) and S. africana (2.87%) were in order of percentage the more abundant species. The abdominal stages of the sandfly species caught in the human habitations are described. P. duboscqi, the suspected vector of cutaneous leishmaniasis in the area, seems to have a preferential domestic biotope.  相似文献   
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