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61.
The immunogenicity of two inactivated bluetongue virus serotype 8 (BTV‐8) vaccines was evaluated in 880 cattle under field conditions. The effect of selected factors on vaccine performance was also analysed at the herd and animal levels (vaccine, herd size and production, age, sex, time interval between vaccination and blood sampling and veterinary training). The immunogenicity elicited by vaccination with the two vaccines was monitored with the aid of a competitive enzyme‐linked immunosorbent assay (c‐ELISA) and serum neutralization test (SNT). To investigate whether the selected factors influenced seroconversion at the herd and animal levels, a multilevel logistic regression model developed in a mixed model was applied. Of the 880 cattle vaccinated, 76.0% yielded BTV c‐ELISA antibodies, whereas only 25.0% seroconverted based on SNT. Type of vaccine (odds ratio [OR] 4.5; 95% confidence interval [CI], 2.2–9.0 for SNT and OR 3.5; 95% CI, 2.1–5.9 for c‐ELISA), veterinary training in vaccine administration (OR 8.1; 95% CI, 4.7–14.1 for SNT and OR 2.4; 95% CI, 1.3–4.2 for c‐ELISA), animal age (OR 1.4; 95% CI, 1.1–1.8 for SNT and OR 1.7; 95% CI, 1.4–2.1 for c‐ELISA) and days between first vaccine administration and blood collection (OR 1.9; 95% CI, 1.1–3.1 for SNT and OR 2.6; 95% CI, 1.7–3.8 for c‐ELISA) were the major factors affecting vaccine performance under field conditions. This is the first study to use multilevel logistic regression in the evaluation of selected risk factors affecting BTV‐8 vaccine performance in cattle.  相似文献   
62.
The aim of the investigation was to assess histologically the effect of laser photobiomodulation (LPBM) on a repair of defects surgically created in the femurs of rats. Forty-five Wistar rats were divided into four groups: group I (control); group II (LPBM); group III (hydroxyapatite guided bone regeneration; HA GBR); group IV (HA GBR LPBM). The animals in the irradiated groups were subjected to the first irradiation immediately after surgery, and it was repeated every day for 2 weeks. The animals were killed 15 days, 21 days and 30 days after surgery. When the groups irradiated with implant and membrane were compared, it was observed that the repair of the defects submitted to LPBM was also processed faster, starting from the 15th day. At the 30th day, the level of repair of the defects was similar in the irradiated groups and those not irradiated. New bone formation was seen inside the cavity, probably by the osteoconduction of the implant, and, in the irradiated groups, this new bone formation was incremental. The present preliminary data seem to suggest that LPMB therapy might have a positive effect upon early wound healing of bone defects treated with a combination of HA and GBR.  相似文献   
63.

Background/Aim

Prognosis assessment in surgical patients with hepatocellular carcinoma (HCC) remains controversial. The most widely used HCC prognostic tool is the Barcelona Clinic Liver Cancer (BCLC) classification, but its prognostic ability in surgical patients has not been yet validated. The aim of this study was to investigate the value of known prognostic systems in 400 Italian HCC patients treated with radical surgical therapies.

Methods

We analyzed a prospective database collection (400 surgical, 315 nonsurgical patients) observed at a single institution from 2000 and 2007. By using survival times as the only outcome measure (Kaplan-Meier method and Cox regression), the performance of the BCLC classification was compared with that of Okuda, Cancer of the Liver Italian Program, United Network for Organ sharing TNM, and Japan Integrated Staging Score staging systems.

Results

Two hundred twenty-five patients underwent laparotomy resection; 55, laparoscopic procedures (ablation and/or resection); and 120, liver transplantations. In the surgical group, BCLC proved the best HCC prognostic system. Three-year survival rates of patients in BCLC Stages A, B, and C were 81%, 56%, and 44% respectively, (P < .01); whereas all other tested staging systems did not show significant stratification ability. When all 715 HCC patients were considered, surgery proved to be a significant survival predictor in each BCLC stage (A, B, and C).

Conclusions

BCLC staging showed the best interpretation of the survival distribution in a surgical HCC population. The BCLC treatment algorithm should consider the role of surgery also for intermediate-advanced stages of liver disease.  相似文献   
64.

Background

Tumor progression before liver transplantation (OLT) is the main cause of dropout from the waiting list (WL) of patients with hepatocellular carcinoma (HCC). The aim of this study was to show a correlation between adopted dropout criteria and dropout/intention-to-treat survival rates of WL HCC patients.

Methods

The study period was 2000 to 2007. The dropout criteria were macroscopic vascular invasion, metastases, or a poorly differentiated tumor. Adult patients with benign chronic liver disease enlisted for primary OLT in the same period represented the control group.

Results

Dropout probability of study (n = 128) versus control group (n = 377) subjects was similar: namely, 12% at 1 year in both groups (P = NS). Intention-to-treat survival curve of the HCC group overlapped that of the benign group (5-year survival rates were 73% and 71%, respectively; P = NS). At the time of listing, 103 study group patients were within the Milan criteria (MC): among these patients, 29 (28%) showed tumor progression beyond MC before OLT. Simulating the dropout of these 29 patients at the time of diagnosis of tumor progression, we compared the dropout probability of the 103 patients within MC with that of the control group. As a result, the 1- and 2-year dropout rates became 37% and 53%, respectively, in the study group, which were significantly higher than those in the controls (P < .01).

Conclusion

HCC patients on the WL showed a significantly greater dropout rate than subjects with benign cirrhosis when too restrictive radiologic dropout criteria were used. The adoption of criteria more related to biological aggressiveness of a tumor decreased the dropout risk for HCC patients without impairing their intention-to-treat survival rates.  相似文献   
65.

Background

Phosphodiesterase 5 inhibitors (PDE5-Is) are a mainstay in the therapy of erectile dysfunction (ED). The primary end point of clinical efficacy, both in clinical studies and normal practice, is represented by the International Index of Erectile Function (IIEF).

Objective

To evaluate if platelet cyclic guanosine monophosphate (cGMP) could represent a valuable marker for PDE5-I activity in ED.

Design, setting, and participants

The study enrolled 46 patients with psychogenic, organic, and mixed ED (20–71 yr of age; IIEF score <26). Patients were randomized to 6 wk of vardenafil, 5 mg/d at bedtime, or placebo.

Intervention

All patients donated two blood samples, one before starting the protocol and the second after 6 wk of treatment.

Measurements

Platelet cGMP was measured in both placebo and vardenafil groups. All the patients completed the IIEF-Erectile Function (EF) domain and the sexual encounter profile (SEP) and underwent visual sexual stimulation (VSS) coupled with Rigiscan. All the measurements were performed prior to starting the protocol and after the 6 wk of treatment.

Results and limitations

Platelet cGMP production was significantly (p < 0.05) elevated in patients taking 5 mg vardenafil versus placebo. Vardenafil was not superior to placebo in improving IIEF-EF and SEP scores. Conversely, VSS-Rigiscan revealed a significant amelioration (p < 0.028) in the vardenafil group versus placebo. The changes in platelet cGMP level correlated well with VSS-Rigiscan (p = 0.0037) but not with IIEF-EF and SEP.

Conclusions

Platelet cGMP could represent a relatively simple, reliable, and objective biomarker of PDE5-I activity in ED clinical studies. Larger clinical studies are needed to further validate the use, utility, and limits of this assay.  相似文献   
66.
Bone marrow is the residence site of mesenchymal stem cells (MSC), which upon commitment and maturation develop into several mesenchymal phenotypes. Recently, we have described the presence of MSC in human cord blood (cbMSC) and informed that their properties are the same as those for MSC obtained from adult bone marrow. In this study we have investigated the capability of transplanted cbMSC to home and survive in the marrow of unconditioned nude mice. cbMSC utilized for transplantation studies were characterized by morphology, differentiation potential, and immunophenotype. After transplantation by systemic infusion, human DNA (as detected by PCR amplification of human-specific beta-globin gene) was detected in the marrow of recipients as well as in ex vivo-expanded stromal cells prepared from the marrow of transplanted animals. These results demonstrate homing and survival of cbMSC into the recipient marrow and also suggest a mesenchymal-orientated fate of engrafted cells, because human DNA was also detected in cells of other recipient tissues, like cardiac muscle, teeth, and spleen.  相似文献   
67.
The gold standard procedure for the evaluation of vesicoureteral reflux (VUR) is the radiographic voiding cystourethrography (VCUG); direct radionuclide voiding cystography (DRVC) is an alternative method for detecting VUR. A new imaging procedure, voiding urosonography (VUS) with contrast medium, has recently been introduced. We have carried out a comparative study of these three techniques in 157 patients (aged 6 weeks–4.7 years). VUS showed the presence of VUR in 91 of 311 renal units; VCUG detected reflux in 64 of 233 renal units, and the DRVC in 23 of 78 renal units. VCUG and VUS were compared in 118 patients, and both procedures showed the same grade of reflux in 56 refluxing units (kappa value 0.92); in six cases the reflux grade was greater at VUS than at VCUG. Seven cases of reflux detected by VUS were not identified on VCUG. VCUG did not show a grade of VUR that was higher than in VUS in any patient. In the identification of 4°–5° grade reflux, the sensitivity of VUS reached 100%. VUS and DRVC were found to be equally effective in the detection of VUR (kappa value 0.85). In conclusion, we found that VUS is a useful method for the diagnosis and grading of patients with VUR.  相似文献   
68.
AIM: Effects of off-pump CABG on LIMA-LAD anastomotic dimensions vs. on-pump CABG assessed by epicardial ultrasound imaging. MATERIAL AND METHODS: LIMA-LAD anastomoses were performed off-pump in 38 patients and on-pump in 12. Intra-operative imaging was by a GE Vivid 7 ultrasound scanner and i13L transducer. Length of the anastomosis (DA), LAD diameters at the toe (D1) and heel (D3) of the anastomosis, the reference downstream LAD (D2) were measured in diastole by two-dimensional imaging (B-mode). Relationships between these dimensions were compared between on- and off-pump patients. RESULTS: In off-pump patients, D3 dimension was smaller than D1 (p=0.004). Both D3 and D1 were smaller than D2 (p<0.01). Ratio D3/D2 was smaller than D1/D2 (p=0.009). In on-pump patients, these ratios were similar. D3/D2 ratio was smaller in off- than in on-pump patients (p=0.01), D1/D2 were similar in the two groups. CONCLUSION: Off-pump CABG may cause a narrowing of the coronaries, especially at the anastomotic heel. The anastomotic technique at the heel may have to be modified to improve its patency.  相似文献   
69.
Pediatric liver transplantation: the University of Padua experience   总被引:1,自引:0,他引:1  
OBJECTIVE: The objective of this study was to analyze experience on pediatric liver transplantation (LT) between June 1993 and September 2006, including split liver transplantation (SLT), living donor liver transplantation (LDLT), and auxiliary partial orthotopic liver transplantation (APOLT). Furthermore, hepatocyte transplantation (HT) had a role in one patient with metabolic disease. METHODS: From November 1990 to September 2006, 657 LTs were performed including 63 pediatric LTs (9.6%) in 57 patients (32 boys and 25 girls). Six were retransplantations (9.5%). Thirty-two patients (57%) were younger than 5 years. The types of graft included the following: 26 whole organs (41%), 32 in situ split organs (51%), 4 reduced-size organs (6%), and 1 graft from a living donor (2%). Two patients received an APOLT, 4 patients received a combined kidney-liver transplantation (CKLT), and 1 patient received HT. Of the 63 pediatric LTs, 16 were behaved to be highly urgent (25%). RESULTS: Overall 1-, 3-, 5-, and 10-year patient survival rates were 82%, 82%, 78%, and 78%, respectively. Overall 1-, 3-, 5-, and 10-year graft survival rates were 76%, 76%, 72%, and 72%, respectively. In patients younger than 1 year, the 5-year survival rate was 100%. Perioperative mortality was 8.8%. Vascular complications occurred in 4 patients (6.3%). Six children required retransplantation due to primary nonfunction (PNF) in 4 cases (7%) and vascular thrombosis in 2 cases (3.5%). CONCLUSIONS: Cholestatic liver disease and age younger than 1 year were the best prognostic factors for excellent survival.  相似文献   
70.
OBJECTIVE: We evaluated the role of type I interferons (IFNs) and IFN receptors in the regulation of cell growth in 3 human pancreatic adenocarcinoma cell lines (BxPC-3, MiaPaCa-2, and Panc-1). BACKGROUND: Chemotherapy and radiotherapy have a marginal role in the management of pancreatic adenocarcinoma. The addition of IFN-alpha showed promising results in early clinical trials. METHODS: Cell proliferation and apoptosis were evaluated by DNA measurement and DNA fragmentation, respectively. Type I IFN receptor (IFNAR-1 and IFNAR-2 subunits) was determined by quantitative RT-PCR and immunocytochemistry. Cell cycle distribution was evaluated by propidium iodide staining and flow-cytometric analysis. RESULTS: The incubation with IFN-beta for 6 days showed a potent inhibitory effect on the proliferation of BxPC-3 (IC(50), 14 IU/mL) and MiaPaCa-2 (IC(50), 64 IU/mL). The inhibitory effect of IFN-beta was stronger than IFN-alpha in all 3 cell lines and mainly modulated by the stimulation of apoptosis, although cell cycle arrest was induced as well. The expression of the type I IFN receptors was significantly higher in BxPC-3 (the most sensitive cell line to IFN) and mainly localized on the membrane, whereas in Panc-1 (the most resistant cell line) about 60% to 70% of cells were negative for IFNAR-2c with a mainly cytoplasmic staining for IFNAR-2c. CONCLUSION: The antitumor activity of IFN-beta is more potent than IFN-alpha in pancreatic cancer cell lines through the induction of apoptosis. Further studies should investigate in vivo whether the intensity and distribution of IFNAR-1 and IFNAR-2c may predict the response to therapy with IFN-alpha and IFN-beta in pancreatic cancer.  相似文献   
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