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1.
Classical and anaplastic seminoma: difference in survival   总被引:1,自引:0,他引:1  
Bobba  VS; Mittal  BB; Hoover  SV; Kepka  A 《Radiology》1988,167(3):849-852
Classical and anaplastic seminoma are traditionally treated with radiation therapy and are said to have the same prognosis. A retrospective study was undertaken of 90 seminoma patients treated with radiation therapy between 1961 and 1985. The classical group consisted of 71 patients of whom 50 had stage I and 21 had stage II disease. The anaplastic group consisted of 19 patients of whom ten had stage I and nine had stage II disease. The median follow-up time was 64 months for the entire group. The 10-year relapse-free survival rate for the classical group was 94% and for the anaplastic group was 70% (P less than .05). For patients with classical stage I disease, the relapse-free actuarial survival rate was 98%; for patients with anaplastic stage I disease, it was 64% (P less than .02). For the classical stage II disease group, the relapse-free actuarial survival rate was 84% and for the anaplastic stage II disease group, 75% (P less than .70). Four patients in the classical group (6%) had relapses; of these, one patient had local recurrence of tumor, and three had distant metastases. In the anaplastic group, four patients (21%) had relapses; two patients had local recurrence of tumor, and two had distant metastases. Therefore the data suggest a difference in survival and relapse rates between classical and anaplastic seminoma.  相似文献   
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We have developed CD4+, tetanus antigen-specific T cell clones that proliferate in the presence of tetanus antigen and autologous irradiated peripheral blood leucocytes (PBL) as antigen-presenting cells (APC). There have been several reports that T cells can present antigen themselves. We have used tetanus antigen-specific T cell clones to examine the effects of envelope glycoproteins of HIV-1 on processing and presentation of antigen to T cells. Cloned T cells were pre-incubated with soluble crude preparation of tetanus antigen for 4 h at 37 degrees C, irradiated, and used as APC (T-APC). These cells could present antigen, as assessed by the ability of the autologous cloned T cells to proliferate. Resting T cells and phytohaemagglutinin-activated T cell blasts from autologous PBL could not present tetanus antigen to the responder cloned T cells. Antigen presentation by T-APC was abrogated by treating cells with anti-HLA-DR but not by anti-HLA-DQ monoclonal antibodies; treatment of tetanus antigen-pulsed T-APC with anti-tetanus antibody also blocked the ability of these cells to induce proliferation in responder T cells. Antigen presentation by cloned T cells was by a chloroquine-resistant pathway. Pretreatment of T-APC with envelope glycoprotein of HIV-1, gp120, did not affect the proliferative responses of the responder T cells. These data suggest that gp120 does not inhibit the antigen-presenting function while suppressing antigen-specific responses.  相似文献   
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Large-conductance Ca2+- and voltage-activated BK-type K+ channels are expressed abundantly in normal rat pancreatic islet cells and in the clonal rat insulinoma tumor (RINm5f) and hamster insulinoma tumor (HIT) beta cell lines. Previous work has suggested that the Ca2+ sensitivity of BK channels in RIN cells is substantially less than that in HIT cells, perhaps contributing to differences between the cell lines in responsiveness to glucose in mediating insulin secretion. In both RIN cells and normal pancreatic beta cells, BK channels are thought to play a limited role in responses of beta cells to secretagogues and in the electrical activity of beta cells. Here we examine in detail the properties of BK channels in RIN and HIT cells using inside-out patches and whole cell recordings. BK channels in RIN cells exhibit rapid inactivation that results in an anomalous steady-state Ca2+ dependence of activation. In contrast, BK channels in HIT cells exhibit the more usual noninactivating behavior. When BK inactivation is taken into account, the Ca2+ and voltage dependence of activation of BK channels in RIN and HIT cells is essentially indistinguishable. The properties of BK channel inactivation in RIN cells are similar to those of inactivating BK channels (termed BKi channels) previously identified in rat chromaffin cells. Inactivation involves multiple, trypsin-sensitive cytosolic domains and exhibits a dependence on Ca2+ and voltage that appears to arise from coupling to channel activation. In addition, the rates of inactivation onset and recovery are similar to that of BKi channels in chromaffin cells. The charybdotoxin (CTX) sensitivity of BKi currents is somewhat less than that of the noninactivating BK variant. Action potential voltage-clamp waveforms indicate that BK current is activated only weakly by Ca2+ influx in RIN cells but more strongly activated in HIT cells even when Ca2+ current magnitude is comparable. Concentrations of CTX sufficient to block BKi current in RIN cells have no effect on action potential activity initiated by glucose or DC injection. Despite its abundant expression in RIN cells, BKi current appears to play little role in action potential activity initiated by glucose or DC injection in RIN cells, but BK current may play an important role in action potential repolarization in HIT cells.  相似文献   
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Several HTLV-I-infected T-cell lines express the two genes encoding platelet-derived growth factor (PDGF). Therefore, we examined the question of a possible self-stimulatory mechanism of proliferation involving PDGF in these cells. Using a nucleic acid probe and an antibody specific for the PDGF-B receptor (PDGFR-B), we examined four established human T-cell lines infected with HTLV-I, as well as several noninfected T-cell lines for expression of the PDGF-B receptor. Previous reports indicate that lymphocytes do not display receptors for PDGF; our results show that two noninfected T-cell lines (HUT-78, CCRF-HSB-2) expressed the canonical 5.5-kb PDGFR mRNA, and two HTLV-I-infected T-cell lines (C10/MJ, MT-2) expressed a novel PDGFR mRNA of 4.8 kb. Concomitantly, the cell lines expressing PDGFR mRNA also synthesize PDGFR proteins immunoprecipitated by the antibody to PDGFR-B. Differences were observed in the molecular weight of PDGFR molecules immunoprecipitated from uninfected and HTLV-infected T-cells. Immunofluorescence studies demonstrated that the PDGFR-B proteins are localized primarily on the cell external membrane. The results suggest that the HTLV-I-infected T-cells acquire an autostimulatory mechanism of cell proliferation that involves PDGF.  相似文献   
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We studied patients with transfusion-associated acquired immunodeficiency syndrome (AIDS) and their blood donors for serologic evidence of infection with human T-cell lymphotropic virus type III/lymphadenopathy-associated virus with two enzyme-linked immunosorbent assays and a Western blot assay. All 19 patients with AIDS were seropositive by at least one test. In all 28 donor sets containing "high-risk" donors, at least one donor was seropositive by one or more tests. Of 255 donors not considered high risk, two (0.8%) were seropositive by all three tests. When 30 seropositive high-risk donors were evaluated a median of 29 months after donation, four (13%) had developed AIDS and eight (27%) had lymphadenopathy. Our findings support the hypothesis that human T-cell lymphotropic virus type III/lymphadenopathy-associated virus causes AIDS and indicate that seropositive high-risk donors may be at relatively high risk for developing AIDS or related conditions themselves.  相似文献   
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Renal transplant (RT) is now a therapy of choice for end stage renal disease (ESRD). The Nephrology Unit, Asvini started functioning in Dec 90 and to date 1298 sittings of hemodialysis have been given to 45 patients. Of these, 35 were in ESRD and 11 patients underwent renal transplantation at this hospital during the period Jan 91 – Dec 93. One patient expired after 18 months of transplantation due to infection. Early experience in screening patients for RT, use of immunosuppression, management of rejection episodes and protocol are presented with special emphasis on its relevance to the Armed Forces.KEY WORDS: Transplantation, Renal Failure, Immunosuppression, Rejection  相似文献   
8.
A 67-year-old woman with lymphoma presented with a neuromyopathy following "laetrile" (amygdalin) treatment. She had significant elevation of blood and urinary thiocyanate and cyanide levels. Sural nerve biopsy specimen revealed a mixed pattern of demyelination and axonal degeneration, the latter being prominent. Gastrocnemius muscle biopsy specimen showed histochemically a mixed pattern of denervation and myopathy with Type II atrophy. It is concluded that cyanide toxicity secondary to laetrile therapy and nutritional deficiency caused the neuromyopathy, as the changes in peripheral nerve are similar to changes described in ataxic polyneuropathy occurring in Nigeria attributed to high cyanide content in the diet and nutritional deficiency. Although this patient received vincristine initially, the development of the neuromyopathy had no temporal relationship to its administration. The clinical profile, as well as peripheral nerve and muscle changes were not similar to either vincristine neuromyopathy or neuromyopathy due to paraneoplastic manifestation of lymphoma. Clinical improvement following discontinuation of "laetrile" by the patient further supports the toxic etiologic results for the neuromyopathy in this patient.  相似文献   
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Background

Nodding Syndrome is a seizure disorder of children in Mundri County, Western Equatoria, South Sudan. The disorder is reported to be spreading in South Sudan and northern Uganda.

Objective

To describe environmental, nutritional, infectious, and other factors that existed before and during the de novo 1991 appearance and subsequent increase in cases through 2001.

Methods

Household surveys, informant interviews, and case-control studies conducted in Lui town and Amadi village in 2001–2002 were supplemented in 2012 by informant interviews in Lui and Juba, South Sudan.

Results

Nodding Syndrome was associated with Onchocerca volvulus and Mansonella perstans infections, with food use of a variety of sorghum (serena) introduced as part of an emergency relief program, and was inversely associated with a history of measles infection. There was no evidence to suggest exposure to a manmade neurotoxic pollutant or chemical agent, other than chemically dressed seed intended for planting but used for food. Food use of cyanogenic plants was documented, and exposure to fungal contaminants could not be excluded.

Conclusion

Nodding Syndrome in South Sudan has an unknown etiology. Further research is recommended on the association of Nodding Syndrome with onchocerciasis/mansonelliasis and neurotoxins in plant materials used for food.  相似文献   
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