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1.
BACKGROUND The adenoma detection rate(ADR) is inversely associated with the incidence of interval colorectal cancer and serves as a benchmark quality criterion during screening colonoscopy. However, adenoma miss rates reach up to 26% and studies have shown that a second inspection of the right colon in retroflected view(RFV) can increase ADR.AIM To assess whether inspection of the whole colon in RFV compared to standard forward view(SFV) can increase ADR.METHODS Patients presenting for screening or surveillance colonoscopy were invited to participate in this randomized controlled trial and randomized into two arms. In RFV arm colonoscopy was initially performed with SFV, followed by a second inspection of the whole colon in RFV. In the SFV arm first withdrawal was performed with SFV, followed by a second inspection of the whole colon again with SFV. Number, size and morphology of polyps found during first and second inspection in each colonic segment were recorded and all polyps were removed and sent for histopathology in separate containers.RESULTS Two hundred and five patients were randomly assigned to the RFV(n = 101) and SFV(n = 104) arm. In the RFV arm, both polyp detection rate(PDR) and ADR were increased under second inspection in RFV(PDR 1~(st) SFV: 39.8%, PDR 2~(nd)RFV: 46.6%; ADR 1~(st) SFV: 35.2%, ADR 2~(nd) RFV: 42%). Likewise, in the SFV arm,PDR and ADR were increased under second inspection(PDR 1~(st) SFV: 37.5%, PDR 2~(nd) SFV: 46.6%; ADR 1~(st) SFV: 34.1%, ADR 2~(nd)SFV: 44.3%) with no significant differences in ADR and PDR between the SFV and RFV arm. Mean number of adenomas per patient(APP) was increased in the RFV and SFV(APP RFV arm: 1~(st) SFV: 1.71; 2~(nd) RFV: 2.38; APP SFV arm: 1~(st) SFV: 1.83, 2~(nd)SFV:2.2). The majority of adenomas additionally found during second inspection in RFV or in SFV were located in the transverse and left-sided colon and were 5 mm in size.CONCLUSION Second inspection of the whole colon leads to increased adenoma detection with no differences between SFV and RFV. Hence, increased detection is most likely a feature of the second inspection itself but not of the inspection mode.  相似文献   
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Objective

To assay peripheral inter-ictal cytokine serum levels and possible relations with non-invasive vagus nerve stimulation (nVNS) responsiveness in migraineurs.

Methods

This double-blinded, sham-controlled study enrolled 48 subjects and measured headache severity, frequency [headache days/month, number of total and mild/moderate/severe classified attacks/month], functional state [sleep, mood, body weight, migraine-associated disability] and serum levels of inflammatory markers [inter-ictal] using enzyme-linked immunoassays at baseline and after 2 months of adjunctive nVNS compared to sham stimulation and suitably matched controls.

Results

No significant differences were observed at baseline and after 2 months for headache severity, total attacks/month, headache days/month and functional outcome [sleep, mood, disability] between verum and sham nVNS. However, the number of severe attacks/month significantly decreased in the verum nVNS group and circulating pro-inflammatory IL-1β was elevated significantly in the sham group compared to nVNS. Levels of anti-inflammatory IL-10 were significantly higher at baseline in both groups compared to healthy controls, but not at 2 months follow-up [p?<?0.05]. Concentrations of high-mobility group box-1 (HMGB-1), IL-6, tumor-necrosis factor-α (TNF-α), leptin, adiponectin, ghrelin remained unchanged [p?>?0.05]. No severe device-/stimulation-related adverse events occurred.

Conclusion

2 months of adjunctive cervical nVNS significantly declined the number of severe attacks/month. Pro-inflammatory IL-1β plasma levels [inter-ictal] were higher in sham-treated migraine patients compared to verum nVNS. However, pro- [IL-6, HMGB-1, TNF-α, leptin] and anti-inflammatory [IL-10, adiponectin, ghrelin] mediators did not differ statistically. Profiling of neuroinflammatory circuits in migraine to predict nVNS responsiveness remains an experimental approach, which may be biased by pre-analytic variables warranting large-scale biobank-based systematic investigations [omics].  相似文献   
4.
Introduction into fetal rat brain cells of a replication-defective retroviral vector harboring v-Ha-ras and v-gag-myc rapidly causes the induction of highly malignant undifferentiated neuroectodermal tumors following transplantation into the brains of syngeneic hosts [Wiestler, et al. (1992) Cancer Res. 52: 3760–3767]. In the present study, we have investigated the modulating effect of the developmental stage of neural target cells and of the dose of the retroviral vector used in the grafting experiments. Exposure of fetal cells from embryonic day (E)12 or E14 produced a 100% incidence of malignant neuroectodermal tumors which led to the death of recipient animals after a median latency period of 32 days. A 100-fold reduction of the virus dose from 2.062×106 to 2.062×104 focus-forming units/ml resulted in a lower tumor incidence of 25%. Of six neural grafts exposed to v-Ha-ras and v-myc at E16, only one showed evidence of tumorigenesis (low-grade astrocytoma and hemangioma). All other transplants were morphologically normal for observation periods of 26 weeks, indicating a marked loss of transforming activity of ras and myc in more advanced stages of brain development. In retrovirus-exposed donor cells which caused the development of neural tumors in recipient rats, malignant transformation was also evident during culture in vitro, usually after 9–12 days. Oncogene complementation was also studied in the newborn rat brain. After microinjection of the retroviral vector into the brain at postnatal day (P)0, P1 and P3, 5 out of 20 animals (25%) developed a total of seven brain tumors. Histopathologically, three of these neoplasms were malignant neuroectodermal tumors which, in contrast to those induced in fetal brain transplants showed evidence of focal glial and/or neuronal differentiation. In addition, we observed one oligodendroglioma, two hemangiomas and a malignant hemangioendothelioma. These data indicate that neural precursor cells and endothelia of the rat brain represent the major target cells for the complementary action of ras and myc and that the use of target cells from later developmental stages (E16 and postnatal) leads to the induction of both primitive and more differentiated neoplasms.These studies were supported by the Fonds zur Förderung der wissenschaftlichen Forschung in Österreich (Erwin Schrödinger fellowship, JO501-MED), by the Swiss National Science Foundation and by the Cancer League of the Kanton of Zürich  相似文献   
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Background: Neuraxial blockade is used as primary anesthetic technique in one third of surgical procedures. The authors tested whether bisoprolol would protect patients at risk for cardiovascular complications undergoing surgery with spinal block.

Methods: The authors performed a double-blinded, placebo-controlled, multicenter trial to compare the effect of bisoprolol with that of placebo on 1-yr composite outcome including cardiovascular mortality, nonfatal myocardial infarction, unstable angina, congestive heart failure, and cerebrovascular insult. Bisoprolol was given orally before and after surgery for a maximum of 10 days. Adrenergic receptor polymorphisms and safety outcome measures of bisoprolol therapy were also determined.

Results: A total of 224 patients were enrolled. Spinal block could not be established in 5 patients. One hundred ten patients were assigned to the bisoprolol group, and 109 patients were assigned to the placebo group. The mean duration of treatment was 4.9 days in the bisoprolol group and 5.1 days in the placebo group. Bisoprolol therapy reduced mean heart rate by 10 beats/min. The primary outcome was identical between treatment groups and occurred in 25 patients (22.7%) in the bisoprolol group and 24 patients (22.0%) in the placebo group during the 1-yr follow-up (hazard ratio, 0.97; 95% confidence interval, 0.55-1.69; P = 0.90). However, carriers of at least one Gly allele of the [beta]1-adrenergic receptor polymorphism Arg389Gly showed a higher number of adverse events than Arg homozygous (32.4% vs. 18.7%; hazard ratio, 1.87; 95% confidence interval, 1.04-3.35; P = 0.04).  相似文献   

7.
We examined whether outer membrane protein A (OmpA) contributes to gram-negative pathogenesis by determining the effect of mutagenesis of ompA in a virulent Escherichia coli K-1 isolate. An OmpA mutant was generated by insertion of the transposon TnphoA, which was genetically modified to increase the efficiency of its delivery by conjugation. The mutant was less virulent than its parent strain in two models of E. coli K-1 infection. Equal inocula of the OmpA+ and OmpA- strains fed to neonatal rats resulted in a sevenfold-greater incidence of bacteremia at 72 h from the OmpA+ strain. The lethal effect of the OmpA- mutant was significantly less than that of the OmpA+ parent strain when inoculated onto the chorioallantoic membrane of 10-day embryonated chick eggs. There was, however, no difference between strains in growth characteristics under physiologic conditions, either in rat serum or in unembryonated chick eggs. In the presence of a 10-day chick embryo, there was a 10-fold increase in the survival and growth of the OmpA+ strain. Correction of the mutation in ompA with an E. coli K-12 ompA gene restored a level of virulence equivalent to that of the parent strain. The ompA mutant was more sensitive to the bactericidal effect of pooled human serum by the classical pathway of complement activation. These results suggest that OmpA contributes to E. coli K-1 pathogenesis by a mechanism which may involve increased serum resistance.  相似文献   
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The influence of the type of reconstruction after gastrectomy upon the postoperative reflux was analyzed in 30 patients. The refluxed material could be directly gained by the long-term reflux aspiration test and, thus, the quality including bile acids could be evaluated. After esophago-jejunoplication and Roux en Y-derivation 5 out of 7 patients were asymptomatic; only one patient suffered from mild esophagitis. Total bile acid concentration was near to the test systems sensitivity. The result in 11 patients after esophago-jejunostomy without Y-en Roux, but with a preserved lower esophageal sphincter (LES) are similar to the former group, whereas in all cases of 12 patients in whom the LES was resected, severe reflux esophagitis and excessively elevated bile acid concentrations were present. These results confirm that a jejunoplication supports the antireflux effect of preserved parts of the LES. If--for oncologic reasons--the LES has to be resected, free intestinal-esophageal reflux is following. In these cases a Roux en Y-derivation is required.  相似文献   
10.
OBJECTIVE: To establish the effectiveness and patient acceptability of initiating peritoneal dialysis (PD) according to published guidelines. SETTING: A university teaching hospital and a neighboring district general hospital. DESIGN: Nonrandomized prospective pilot study. PATIENTS: 39 patients with a Kt/V > 2.0 attending predialysis clinics at both hospitals agreed to participate in this study. METHODS: Patients were started on a single exchange of dialysate overnight. Dialysis adequacy was monitored at least every 2 months and incremental increases in dialysis were used to maintain combined urinary and dialysis Kt/V above 2.0. Routine laboratory parameters and complications of dialysis were monitored during the follow-up period. RESULTS: The mean weekly Kt/V at initiation of dialysis was 2.09. Median actuarial survival on a single exchange before requiring incremental dialysis was 297 days. At the end of the study period, all patients were still alive: 8 remained on 1 exchange, 18 were on more than 1 exchange, 8 had switched to hemodialysis, and 5 had received renal transplants. During the 12,665 patient-days on single-exchange dialysis, there were 14 hospital admissions of 12 patients. This resulted in a mean of 1.64 hospital days per patient-year for the whole group. During the follow-up period there were 2 episodes of bacterial peritonitis, 3 pleural leaks, 1 patent processus vaginalis, and 1 inguinal hernia that required surgical intervention. The use single daily icodextrin exchanges was associated with a 46% incidence of culture-negative peritonitis. CONCLUSIONS: This pilot study has shown that a timely start of dialysis with a single overnight PD exchange is acceptable to patients. Incremental dialysis as residual renal function falls is easily managed and patients also find this acceptable. Complication and hospitalization rates were low. The presence of residual renal function often allows complications to be managed without the need for hemodialysis. The use of icodextrin as a single-exchange dialysate is associated with sterile peritonitis in a significant proportion of cases.  相似文献   
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