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941.
942.
Purpose The risk factors for secondary stomach carcinogenesis after distal gastrectomy have not been evaluated in detail. Methods Using gastrointestinal endoscopy, we examined 112 patients who had undergone gastrectomy. Biopsy specimens were taken from the stoma and the upper corpus mucosa in the remnant stomach to examine the associations among Helicobacter pylori (H.pylori) infection, bile reflux, and the expressions of interleukin-8 (IL-8), cyclo-oxygenase-2 (COX-2), and trefoil factor family 1 (TFF1) genes in the stomach mucosa. Results The IL-8 levels in the corpus mucosa were significantly higher in the H.pylori-positive patients than in the H.pylori-negative patients (P = 0.015). The IL-8 levels were significantly higher in the stomal mucosa than in the corpus mucosa in the H.pylori-positive patients (P = 0.047). The COX-2 levels in the corpus mucosa tended to be higher in the H.pylori-positive patients, but these levels were not significantly different in the stoma mucosa. The COX-2 levels in the corpus were significantly higher after Billroth II (BII) anastomosis than after Billroth I (BI) anastomosis (P = 0.041). TFF1 expression in the stoma was higher in the H.pylori-positive patients than in the H.pylori-negative patients, but the difference was not significant. Conclusions Both H.pylori infection and bile reflux increased IL-8 levels after BI anastomosis. Furthermore, COX-2 levels were higher after BII than after BI anastomosis. These indicators will become useful not only as biomarkers to predict the degree of inflammation in the stomach mucosa, but also as surrogate biomarkers to predict the risk of secondary stomach carcinogenesis in the remnant stomach mucosa.  相似文献   
943.
Aim: To investigate the changes of the spermatozoa ultrastructures before and after renal transplantation in uremic patients. Methods: The sperm of five uremic patients before and after transplantation and four healthy volunteers were collected and examined by scanning electron microscopy. Results: Abnormal spermatozoa were found in patients pre-transplantation; abnormalities included deletion of the acrosome, absence of the postacrosomal and postnuclear ring, dumbbell-like changes of the head, tail curling, and absence of the mitochondrial sheath in the midsegment. After renal transplantation, most of the spermatozoa became normal. Conclusion: There are many abnormalities with regard to the appearance and structure of the head, acrosome, mitochondria and tail of the spermatozoa in uremic patients. The majority of the spermatozoa returned to normal after renal transplantation, but a few still presented some abnormalities possibly relating to the administration of immunosuppressants.  相似文献   
944.
945.
症状监测及其在应对突发公共卫生事件中的作用   总被引:22,自引:0,他引:22  
及早地识别公共卫生事件的发生,并做出迅速而有效的反应以降低患病率和死亡率一直是公共卫生工作的首要目标之一。而在面临突发公共卫生事件时,无论从挽救生命或减少经济损失而言,对及时性的要求都变得更为突出和重要。研究结果表明,在大规模炭疽杆菌微粒播散事件的初期,应答反应延迟1h就会多损失2亿美元。因此,应对突发公共卫生事件要求分秒必争。  相似文献   
946.
Leishmune vaccine is the first licensed vaccine against canine visceral leishmaniasis. It contains the Fucose-Mannose-ligand (FML) antigen of Leishmania donovani. The potential Leishmune vaccine effect on the interruption of the transmission of the disease, was assayed by monitoring, in untreated (n=40) and vaccinated dogs (n=32) of a Brazilian epidemic area: the kala-azar clinical signs, the FML-seropositivity and the Leishmania parasite evidence by immunohistochemistry of skin and PCR for Leishmanial DNA of lymph node and blood samples. On month 11 after vaccination, untreated controls showed: 25% of symptomatic cases, 50% of FML-seropositivity, 56.7% of lymph node PCR, 15.7% of blood PCR and 25% of immunohistochemical positive reactions. The Leishmune-vaccinated dogs showed 100% of seropositivity to FML and a complete absence of clinical signs and of parasites (0%) in skin, lymph node and blood PCR samples (p<0.01). The positivity in FML-ELISA in untreated dogs significantly correlates with the PCR in lymph node samples (p<0.001) and with the increase in number of symptoms (p=0.006) being strong markers of infectiousness. The absence of symptoms and of evidence of Leishmania DNA and parasites in Leishmune-vaccinated animals indicates the non-infectious condition of the Leishmune-vaccinated dogs.  相似文献   
947.
948.
BACKGROUND: IgA nephropathy (IgAN) is the most common glomerulonephritis with various histologic and clinical phenotypes. The mechanisms underlying the pathogenesis of IgAN remained unclear. But now altered O-glycosylation of serum IgA1 observed in these patients was considered to be a key contributory factor. The aim of the current study is to investigate whether aberrantly glycosylated IgA1 was associated with pathologic phenotypes of IgAN. METHODS: Sera from 107 patients with IgAN recently diagnosed were collected. Fifty patients were with mild mesangial proliferative IgAN, the others were with focal proliferative and sclerosing IgAN. Sera from 22 normal blood donors were used as normal controls. Biotinylated lectins were used in enzyme-linked immunosorbent assay (ELISA) to examine different glycans on IgA1 molecules. The alpha2,6 sialic acid was detected by elderberry bark lectin (SNA), the exposure of terminal galactose (Gal) and N-acetylgalactosamine (GalNAc) were detected by arachis hypogaea [peanut agglutinin (PNA)] and vilsa villosa lectin (VVL), respectively. The serum IgA1 glycans levels corrected by serum IgA1 concentrations were compared between patients and controls. RESULTS: Reduced terminal alpha2,6 sialic acid (1.16 +/- 0.21 vs. 0.98 +/- 0.31) (P= 0.008) and galactosylation (0.30 +/- 0.29 vs. 0.16 +/- 0.19) (P= 0.029) increased exposure of (GalNAc) (0.00 vs. 0.03) (P= 0.024) were demonstrated in serum IgA1 from patients with IgAN as compared with those in controls. More important, the exposures of 2,6 sialic acid and Gal were significantly decreased, especially in patients with focal proliferative and sclerosing IgAN compared with that in patients with mild mesangial proliferative IgAN (0.91 +/- 0.34 vs. 1.05 +/- 0.25) (P= 0.014) (0.108 +/- 0.137 vs. 0.221 +/- 0.219) (P= 0.018). However, no significant difference was found between patients with mild mesangial proliferative IgAN and normal controls (P > 0.05). The exposure of GalNAc of serum IgA1 from patients with focal proliferative and sclerosing IgAN was significantly higher than that of controls (P= 0.017), but had no statistical difference with that of patients with mild mesangial proliferative IgAN. CONCLUSION: The desialylation and degalactosylation of IgA1 in sera of patients with IgAN were closely associated with pathologic phenotypes.  相似文献   
949.
950.
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