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71.
Understanding and identifying new ways of mounting an effective CD8+ T cell immune response is important for eliminating infectious pathogens. Although upregulated programmed death-1 (PD1) in chronic infections (such as HIV-1 and tuberculosis) impedes T cell responses, blocking this PD1/PD-L pathway could functionally rescue the “exhausted” T cells. However, there exists a number of PD1 spliced variants with unknown biological function. Here, we identified a new isoform of human PD1 (Δ42PD1) that contains a 42-nucleotide in-frame deletion located at exon 2 domain found expressed in peripheral blood mononuclear cells (PBMCs). Δ42PD1 appears to function distinctly from PD1, as it does not engage PD-L1/PD-L2 but its recombinant form could induce proinflammatory cytokines. We utilized Δ42PD1 as an intramolecular adjuvant to develop a fusion DNA vaccine with HIV-1 Gag p24 antigen to immunize mice, which elicited a significantly enhanced level of anti-p24 IgG1/IgG2a antibody titers, and important p24-specific and tetramer+CD8+ T cells responses that lasted for ≥7.5 months. Furthermore, p24-specific CD8+ T cells remain functionally improved in proliferative and cytolytic capacities. Importantly, the enhanced antigen-specific immunity protected mice against pathogenic viral challenge and tumor growth. Thus, this newly identified PD1 variant (Δ42PD1) amplifies the generation of antigen-specific CD8+ T cell immunity when used in a DNA vaccine.  相似文献   
72.
Surface shield: device to reduce personnel radiation exposure   总被引:2,自引:0,他引:2  
A simple device is described that can reduce personnel exposure from scatter radiation by up to 75%. The device consists of an oblong piece of shielding (0.75-mm lead equivalent) that is taped to the side of the patient during percutaneous renal stone removal and other interventional procedures. Contrary to other shields and barriers, this does not interfere with access to the patient. Scatter exposure data from phantom studies are presented and the rationale for surface shielding discussed.  相似文献   
73.
OBJECTIVE: To evaluate the accuracy of a rapid assay that wasdeveloped to detect Helicobacter pylori antigen in the stool,using the principle of immunochromatography, in the Chinese population. METHODS: Eligible patients without prior treatment of H.pylori were recruited. An in‐house rapid urease test (RUT) andhistology were used as the gold standard. The results of the rapidstool antigen test were compared with the gold standard. RESULTS: Valid rapid stool antigen test results for interpretationwere obtained from 94 consecutive patients (mean age: 52.5, range:22?82 years). Sensitivity, specificity, positive predictivevalue, negative predictive value and accuracy were, respectively, 77.5%,87.0%, 81.6%, 83.9% and 83.0%.The test was easy to perform and results were available within 15 min. CONCLUSION: The rapid stool antigen test using immunochromatography accuratelydiagnoses H. pylori infection in Chinese patients.  相似文献   
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Focal liver masses: differential diagnosis with pulsed Doppler US   总被引:8,自引:0,他引:8  
Duplex Doppler ultrasound (US) was used in 68 consecutive patients with focal liver lesions, including 12 hepatocellular carcinomas, one cholangiocarcinoma, 37 metastases, 15 hemangiomas, one hemangioendothelioma, and two focal nodular hyperplasias. Of the hepatocellular carcinomas, six were diffusely hyperechoic, two were hypoechoic, two were single hyperechoic lesions, and two were multifocal and hyperechoic. All ten tumors with Doppler shifts of 5 kHz or above proved to be hepatocellular carcinomas. The other two hepatocellular carcinomas showed Doppler shifts of 3 kHz. In contrast, no hemangioma showed shifts above 0.7 kHz, and ten of the 15 gave no detectable signal. Of the metastases, 20 gave no signal and 17 had signals of up to 4 kHz. Three-kilohertz signals were also obtained from a cholangiocarcinoma, a hemangioendothelioma, and focal nodular hyperplasia. Correlation with angiographic findings suggested that the high-velocity Doppler signals were associated with large pressure gradients due to arteriovenous shunting. Duplex Doppler US can therefore aid in the differential diagnosis of diffuse and focal liver lesions.  相似文献   
77.
Vascular complications after liver transplantation include occlusion or stenosis near the sites of anastomosis in the hepatic artery, portal vein, and vena cava. Balloon angioplasty of these stenoses carries little risk and is a useful procedure for the treatment of these problems. Here we describe the case of a liver transplant patient who underwent balloon angioplasty for stenosis of the hepatic artery and who developed spasms of the hepatic artery which were aggravated following intraarterial administration of Tolazoline. Received: 0/00/000 Accepted: 0/00/00  相似文献   
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Summary Hepatic candidiasis represents an increasingly difficult problem in immunocompromised patients. It has been recognized as a variant of disseminated candidiasis after a period of neutropenia. Establishment of diagnosis is difficult since liver biopsy as well as culture may be negative, in spite of the presence of fungus. Hepatic lesions are generally not detectable by ultrasound examination or computed tomography until the neutrophil count has returned to normal. The aim of this case report is to describe the problems related to the diagnosis and treatment of hepatic candidiasis following chemotherapy for acute leukemia. The report also provides further evidence that fluconazole, a new broad-spectrum antifungal drug, can be safely and effectively used for the long-term treatment of deep-seated hepatic candidiasis.  相似文献   
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