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61.
Serologic response to human oncogenic papillomavirus types 16, 18, 31, 33, 39, 58 and 59 virus-like particles in colombian women with invasive cervical cancer 总被引:22,自引:0,他引:22
Combita AL Bravo MM Touzé A Orozco O Coursaget P 《International journal of cancer. Journal international du cancer》2002,97(6):796-803
The serologic response against virus-like particles (VLP) from 7 high risk genital papillomaviruses was investigated by ELISA in 147 Colombian women with invasive cervical cancer and 147 age-matched cytologically normal and HPV-DNA negative women. Anti-VLP antibodies were detected in 82% of the invasive cervical cancer patients and in 56% of the controls. Detection of antibodies against multiple HPV types is the rule and the presence of high antibody titers was associated with higher survival of cancer patients. Higher anti-VLP seroprevalence was observed in younger cancer patients. In those followed serologically for 1 year, antibodies generally remained at the same level. However, in some patients an increase or decrease in antibody levels occurred simultaneously for multiple HPV types, suggesting cross-reactivity between the HPV types investigated. Investigation of seroreactivity between 8 high risk HPVs suggested that there is some cross-reactivity between phylogeneticaly-related types such as 16, 31, 33 and 58; and 18, 45 and 59. In conclusion, our results confirmed (i) the high rate of HPV infections in Colombia, both in patients with cervical cancer and in the general population, and the particularly high rate of infections due to HPV 31 and 58; and (ii) the validity of anti-VLPs as a marker of present or past HPV infection. The simultaneous appearance or disappearance of antibodies against multiple HPV VLPs suggests that the antibodies detected by ELISA are not always type specific. 相似文献
62.
Orozco H Mercado MA Chan C Ramos-Gallard G Gálvez-Treviño R Salgado-Nesme N Cisneros De-ajuria R Anthón FJ 《Annals of hepatology》2002,1(4):175-178
Portal hypertension surgery has evolved widely in the last decades. Since the first surgical shunt was done in 1945 for the treatment of recurrent hemorrhage, many surgical options have been developed including selective shunts, low diameter shunts and extensive devascularization procedures. Many of them have been studied and compared showing their advantages and disadvantages, evolving also their role in the therapeutic armamentarium. Surgery is nowadays a second line treatment option (after b blockers and endoscopic therapy), and it's main indication is for patients whose main and only problem is history of bleeding, with good liver function (Child-Pugh A). For emergency situations it has a very limited role and for primary prophylaxis virtually has also no role. Patients with good liver function, electively operated with portal blood flow preserving procedures are the patients that benefit from surgical treatment. Patients with a bad liver function are better candidates for a liver transplant. 相似文献
63.
64.
Waterston–Cooley anastomosis may be carried out in patients with tricuspid atresia to provide pulmonary perfusion. It is associated with several complications, including preferential blood flow to the right lung, hypoplasia of the left pulmonary artery, obstruction of the anatomosis or rupture of pulmonary aneurysms. We study a patient with thrombosis in the pulmonary arteries following surgical construction of a Waterston shunt in childhood. Imaging findings and clinical symptoms are discussed with emphasis on echocardiogram‐gated multislice spiral CT. 相似文献
65.
The relationship between the insulin-breakfast interval, postprandial increase in blood glucose, and glycaemic control was studied in 58 children with diabetes. Patients recorded insulin-breakfast intervals in a home diary over a seven day period, and during a 24 hour period at the weekend provided eight serial capillary dried blood spots for glucose analysis. The highest mean blood glucose value occurred two hours after breakfast and showed a significant correlation with fructosamine concentrations. Weekend insulin-breakfast intervals ranged from 2-30 minutes, with 70% reporting intervals of less than 15 minutes. There was a significant correlation between the weekend insulin-breakfast interval and the after breakfast increase in blood glucose with a mean increment of 0.4 mmol/l in the 30 minute group and 7.2 mmol/l in the 2 minute group. Over the whole study period, children with mean insulin-breakfast intervals of two to 12 minutes had a mean fructosamine concentration of 376 mumol/l compared with 341 mumol/l in those with intervals of 15-35 minutes. This study has shown that the interval between insulin injection and breakfast significantly influences the morning postprandial rise in blood glucose and consequently short term glycaemic control. It is therefore important that patients are encouraged to leave an interval of about 30 minutes between insulin injection and breakfast. 相似文献
66.
67.
Colorectal hemangioma: radiologic findings 总被引:1,自引:0,他引:1
The authors correlated radiographs with the clinical and histologic data of 12 patients with colorectal hemangioma. All patients presented with rectal bleeding, which was chronic in seven. Phleboliths were also visible in seven cases, which correlated with chronic bleeding in five. On barium studies, three masses were soft and three produced rigid narrowing. The atypical features of rigid luminal narrowing, which might mimic a carcinoma, and hypovascularity correlated with chronic bleeding or visible phleboliths, which suggest the correct diagnosis of colorectal hemangioma. 相似文献
68.
Early human thymocyte proliferation is regulated by an externally controlled autocrine transforming growth factor-beta 1 mechanism 总被引:4,自引:2,他引:2
Mossalayi MD; Mentz F; Ouaaz F; Dalloul AH; Blanc C; Debre P; Ruscetti FW 《Blood》1995,85(12):3594-3601
Early thymocytes undergo extensive proliferation after their entry into the thymus, but cellular interactions and cytokines regulating this intrathymic step remain to be determined. We analyzed the effects of various T-cell growth factors and cellular interactions on in vitro proliferation of early CD2+CD3/TCR-CD4-CD8- (triple negative [TN]) human thymocytes. Freshly isolated TN cells were then assayed for their growth capacity after incubation with CD2I+III-monoclonal antibody (MoAb), recombinant human interleukin-2 (IL-2), IL-7, and/or IL-4. These cells displayed significant proliferative responses with IL-4, IL- 7, or CD2-MoAb+IL-2. The addition of recombinant transforming growth factor beta (TGF beta) or autologous irradiated CD3+CD8+CD4- cells to TN cell cultures dramatically decreased their growth responses to IL-2 and IL-7, whereas IL-4-induced proliferation was less sensitive to growth inhibition. We thus asked whether the CD8+ cell-derived inhibitory effect was due to TGF beta. The addition of neutralizing anti-TGF beta MoAb completely abolished CD8+ cell-derived inhibition of TN cell growth. Analysis of CD8+ cell-derived supernatants indicated that these cells had low TGF beta 1 production capacity, whereas TN cells secrete significantly high levels of TGF beta 1. Cell fixation studies showed that TN cells were the source of the TGF beta. TGF beta 1 released from TN cells was in the latent form that became the active inhibitory form through interaction of TN cells with CD8+ cells. Together, these data suggest a role for TGF beta 1 as an externally controlled, autocrine inhibitory factor for human early thymocytes, with a regulatory role in thymic T-cell output. 相似文献
69.
In this paper we report the occurrence of changes in the migration of certain isoenzymes of a cloned strain (MAV-CINVESTAV) ofEntamoeba histolytica. This strain was isolated from an asymptomatic carrier and showed an initial nonpathogenic zymodeme I. The transfer of polyxenic trophozoites from Robinson's medium (7% serum) to Jones' medium (30% serum) provoked changes in isoenzyme expression, resulting in the conversion of zymodeme I to a zymodeme that was similar to the XVII zymodeme except for two slow-running bands and a single fast-running band that were detected for hexokinase (HK). This XVII-like zymodeme reverted to zymodeme I when trophozoites were cultured under monoxenic conditions in TY1-S-33 medium (10% serum). When we cultured cloned strain MAV-CINVESTAV under axenic conditions in TY1-S-33 medium, trophozoites expressed a pathogenic zymodeme with two fast-running HK bands and a betaphosphoglucomutase band. In addition, phagocytosis and the ability of the trophozoites to destroy cell-culture monolayers were expressed only in trophozoites cultured under axenic conditions. The axenization procedure required the presence of liveFusobacterium symbiosum and is also described herein.Abbreviations HK
hexokinase
- ME
l-malate: NADP+ oxidoreductase
- GPI
glucose phosphate isomerase
- PGM
phosphoglucomutase
- P
pathogenic
- NP
nonpathogenic
- px
polyxenic
- mx
monoxenic
- ax
axenic 相似文献
70.
Patient survival characteristics after routine mitral valve repair for ischemic mitral regurgitation 总被引:4,自引:0,他引:4
Glower DD Tuttle RH Shaw LK Orozco RE Rankin JS 《The Journal of thoracic and cardiovascular surgery》2005,129(4):860-868
BACKGROUND: Ischemic mitral regurgitation has been associated with diminished survival compared with nonischemic mitral regurgitation. Conversion from mitral valve replacement to valve repair has improved prognosis, but it is unclear whether ischemic mitral regurgitation remains an independent predictor of outcome after mitral valve repair. METHODS: Five hundred thirty-five patients undergoing mitral valve repair (primarily rigid ring annuloplasty) with or without coronary bypass from 1993 through 2002 were reviewed retrospectively (ischemic mitral regurgitation, n = 141; nonischemic mitral regurgitation, n = 394). A Cox proportional hazards model evaluated survival as a function of 9 simultaneous covariates: ischemic versus nonischemic mitral regurgitation, age, sex, number of medical comorbidities, ejection fraction, New York Heart Association class, coronary disease, reoperation, and year of operation. RESULTS: According to univariable analysis, patients with ischemic mitral regurgitation had greater age, higher comorbidity, lower ejection fraction, higher New York Heart Association, and higher reoperation rate (all P < .001) compared with those having nonischemic mitral regurgitation. Univariable 30-day mortality was as follows: 4.3% for patients with ischemic mitral regurgitation versus 1.3% for patients with nonischemic mitral regurgitation (P = .01). Unadjusted 5-year mortality was as follows: 44% +/- 5% for patients with ischemic mitral regurgitation versus 16% +/- 3% for patients with nonischemic mitral regurgitation (P < .001). In the multivariable model, however, only the number of preoperative comorbidities and advanced age were independent predictors of survival (P < .0001), whereas ischemic mitral regurgitation, sex, ejection fraction, New York Heart Association class, coronary disease, reoperation, and year of operation did not achieve significance (all P > .19). After being adjusted for differences in all preoperative risk factors, survival was not statistically different between ischemic mitral regurgitation and nonischemic mitral regurgitation (P = .33). CONCLUSIONS: With routine application of rigid ring annuloplasty, long-term patient survival is more influenced by baseline patient characteristics and comorbidity than by ischemic cause of mitral regurgitation per se. Future risk assessment and decision making should be based on patient condition and should not be biased by ischemic cause of mitral regurgitation. 相似文献