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11.
In order to enhance the immune efficacy of DNA vaccination, experiments were conducted to investigate the regulating effects of Bacillus Calmette-Guerin (BCG)-DNA as an adjuvant on immune responses of mice against foot-and-mouth disease (FMD), Aujeszky's disease (AID) and classical swine fever (CSF). BCG-DNA was purified from BCG by ion-exchange chromatography. Three DNA vaccines (pVSG, pVgD and pVE2) against the respective infection were constructed, and BCGDNA was coimmunized to mice by muscle injection. The results showed that titres of specific immunoglobulin (Ig)G to the vaccines mounted remarkably in the sera of the adjuvant covaccinated mice (P〈0.01). Antibody isotype IgG2a and IgG1 also increased, respectively, in mice coimmunized with BCG-DNA compared with those of the control groups (P〈0.01). Cellular immune cytokine interferon-gamma and cytotoxic T lymphocytes were detected in coimmunized BCG-DNA groups (P〈0. 05). Whereas interleukin-4, humoral immune cytokine, was not significant (P〉 0. 05). These results suggest that codelivery of BCG-DNA with DNA vaccines against FMD, AjD and CSF can enhance the induction of antigen-specific, especially, cell-mediated immunity. 相似文献
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ObjectivesThe aim of the present study is to evaluate the feasibility and safety of performing PNL under local anesthesia in a selected group of patients who are at high risk for general anesthesia.Patients and methodsForty seven patients underwent PNL under local anesthesia. There were 38 males and 9 females with a mean age of 62 years. All patients were at medical high-risk for general anesthesia, with an American Society of Anesthesiologists (ASA) score of 3. The indications for local anesthesia in this study were obstructed single functioning kidney with azotemia in 29 patients, hepatic insufficiency in 8 patients, cardiac problems in 7 patients and 3 patients had hepatocellular carcinoma. The mean stone size was 2.7 cm (range 2–3.1 cm). Local infiltration with 10–20 cc of 2% lidocaine at the site of puncture was used in all cases. Narcotics were given 30 min prior to the procedure and medazolam was given intraoperatively upon demand. Utrasound guided puncture was performed in all cases and tract dilatation was then done under fluoroscopy using high pressure balloon catheter in 35 and Alken's metal dilators in 12 cases. Stones were then retrieved after disintegration in the same cession in 33 patients, while the other 14 patients underwent staged PNL, where a 12 Fr. nephrostomy tube was placed in the first stage, followed by tract dilatation and stone retrieval one week later.ResultsOut of 47 patients included, 44 had successful PNL either one stage (30 patients) or two stages (14 patients). Only 3 patients could not tolerate pain and the procedure was terminated after placement of nephrostomy tube and stone retrieval was completed later under general anesthesia.ConclusionOur results demonstrated that PNL under local anesthesia with narcotics and sedatives seems to be a satisfying solution for the treatment of a selected group of patients with renal pelvic stones and who have high anesthetic risk. However, additional studies with different groups of patients are required to validate our results. 相似文献
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Decreased expression of phospholipase C-beta 2 isozyme in human platelets with impaired function 总被引:4,自引:4,他引:4
Platelets from a patient with a mild inherited bleeding disorder and abnormal platelet aggregation and secretion show reduced generation of inositol 1,4,5-trisphosphate, mobilization of intracellular Ca2+, and phosphorylation of pleckstrin in response to several G protein mediated agonists, suggesting a possible defect at the level of phospholipase C (PLC) activation (see accompanying report). A procedure was developed that allows quantitation of platelet PLC isozymes. After fractionation of platelet extracts by high-performance liquid chromatography, 7 out of 10 known PLC isoforms were detected by immunoblot analysis. The amount of these isoforms in normal platelets decreased in the order PLC- gamma 2 > PLC-beta 2 > PLC-beta 3 > PLC-beta 1 > PLC-gamma 1 > PLC- delta 1 > PLC-beta 4. Compared with normal platelets, platelets from the patient contained approximately one-third the amount of PLC-beta 2, whereas PLC-beta 4 was increased threefold. These results suggest that the impaired platelet function in the patient in response to multiple G protein mediated agonists is attributable to a deficiency of PLC-beta 2. They document for the first time a specific PLC isozyme deficiency in human platelets and provide an unique opportunity to understand the role of different PLC isozymes in normal platelet function. 相似文献
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Rationale:Traumatic arteriovenous fistulas (AVFs) of the pelvis are uncommon and present with a variety of clinical manifestations; their detection may be difficult. An endovascular approach is usually the first choice of treatment, because surgical intervention is complicated due to the location of the lesions.Patient concerns:A 68-year-old man was admitted with severe pelvic pain following a fall.Diagnosis:A pelvic bone fracture (Young and Burgess Classification, lateral compression type II) was revealed on pelvic computed tomography (CT), while a pelvic sidewall hematoma, unaccompanied by any vascular injury, was detected on multidetector CT.Interventions:Pelvic angiography revealed an AVF between the internal iliac artery and vein, which was undetected by MDCT. The AVF was successfully treated using transcatheter arterial embolization (TAE) with n-butyl cyanoacrylate (NBCA).Outcomes:The patient recovered well and was discharged 4 weeks later. No complications were noted at the 8-month follow-up.Lessons:AVF may occur as a complication of blunt pelvic bone fracture. A high index of suspicion, angiography, and prompt diagnosis resulted in the successful management of our patient who presented with risk factors. Furthermore, TAE using NBCA enables a minimally invasive and effective treatment of traumatic pelvic AVF. 相似文献
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Possible effect of secretor locus on plasma concentration of factor VIII and von Willebrand factor 总被引:2,自引:1,他引:2
A significant fraction (30%) of the genetically determined variance in plasma concentration of the von Willebrand factor antigen (vWf:Ag) has been shown to be related to ABH determinants. Individuals with blood group O, who have the highest amounts of blood group H substance, have the lowest concentration of vWf:Ag. The Lewis substances, Le(a) and Le(b), are biochemically closely related to the ABH substances as both can be produced from the same precursor substance. We studied the effect of the presence of the Lewis antigens on the plasma concentration of vWf:Ag and factor VIII antigen (VIII:Ag) in 323 individuals of different ABO groups from a series of twins and in 58 blood donors of blood group O. Among persons belonging to blood group O, those with the Le(a) antigen had a higher concentration of both vWf:Ag and VIII:Ag than individuals lacking Le(a). Le(a+b-) people are nonsecretors and Le(a-b+) people are secretors of ABH substance. Thus, the lowest concentration of vWf:Ag and VIII:Ag was found in group O secretors. The effect is most likely due to an effect of the secretor locus. This finding may be of importance for the detection of carriers of hemophilia A and for the diagnosis of type I von Willebrand disease. 相似文献
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A New Asymmetric Directional Microphone Algorithm With Automatic Mode‐Switching Ability for Binaural Hearing Support Devices
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Jinryoul Kim Kyoung Won Nam Sunhyun Yook Dong Pyo Jang In Young Kim Sung Hwa Hong 《Artificial organs》2015,39(6):535-540
For hearing support devices, it is important to minimize the negative effect of ambient noises for speech recognition but also, at the same time, supply natural ambient sounds to the hearing‐impaired person. However, conventional fixed bilateral asymmetric directional microphone (DM) algorithms cannot perform in such a way when the DM‐mode device and a dominant noise (DN) source are placed on the same lateral hemisphere. In this study, a new binaural asymmetric DM algorithm that can overcome the defects of conventional algorithms is proposed. The proposed algorithm can estimate the position of a specific DN in the 90°–270° range and switch directional‐ and omnidirectional‐mode devices automatically if the DM‐mode device and the DN are placed in opposite lateral hemispheres. Computer simulation and KEMAR mannequin recording tests demonstrated that the performance of the conventional algorithm deteriorated when the DM‐mode device and the DN were placed in the opposite hemisphere; in contrast, the performance of the proposed algorithm was consistently maintained regardless of directional variations in the DN. Based on these experimental results, the proposed algorithm may be able to improve speech quality and intelligibility for hearing‐impaired persons who have similar degrees of hearing impairment in both ears. 相似文献
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