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1.
Inactivation of viruses in blood products requires that the method employed display selectivity in its action for viral elements while not affecting the biological entity of interest. Several methods have been developed for the treatment of human plasma or products derived from human plasma. An effective technique for the treatment of the cellular components of blood has been lacking, in part due to the inability to develop agents capable of selectively targeting viral agents in the milieu of cellular material. In this paper, we examine the behavior of a group of viral sensitizers designed to be added to cellular samples and be activated upon exposure to UVA light. Upon activation, these agents are capable of disrupting nucleic acids of the virus in a manner that renders them inactive for proliferation. The selectivity observed in this inactivation is determined by the chemical structure of the sensitizer, which can be varied to increase viral killing capacity while diminishing collateral damage to cellular and protein constituents.  相似文献   
2.
Ossification of the posterior longitudinal ligament (OPLL) is a progressive disorder of the spine which may result in spinal cord compression and myelopathy. While prevalent among Japanese, its occurrence in non-Orientals has been infrequently reported. Nine patients with OPLL have been diagnosed and followed at the Emory Clinic Spine Center over a 5-year period. All of the patients had been misdiagnosed before presentation. Five of the nine had undergone a total of eight ineffective operations. Failure to distinguish OPLL from other more common causes of myelopathy can result in delayed or inappropriate treatment. Illustrative cases and radiographic studies are presented.  相似文献   
3.
目的 探讨人疱疹病毒6型(HHV-6)感染的免疫发病机理。方法 用逆转录-聚合酶链反应(RT-PCR)和双抗体夹心酶联免疫吸附试验(ELISA)检测白细胞介素^-10(IL-10)等细胞因子的产生。结果 HHV-6诱导单核细胞表达和产生IL-10,细胞因子mRNA动力学研究发现TNF-α(肿瘤坏死因子)、IL-1β及IL-6随IL-10mRNA积累而减少,用抗人IL-10单克隆抗体阻断HHV-6诱  相似文献   
4.
BACKGROUND. Cytomegalovirus (CMV) infection is a major cause of morbidity and mortality after allogeneic bone marrow transplantation. We conducted a controlled trial of ganciclovir for the early treatment of CMV infection in asymptomatic recipients of bone marrow transplants whose surveillance cultures for CMV became positive. METHODS. Bone marrow--allograft recipients who were seropositive for CMV antibodies or who received seropositive marrow were screened for CMV excretion by culture of throat swabs, blood, urine, or bronchoalveolar-lavage fluid. In this double-blind trial, 72 patients who had marrow engraftment and were excreting virus were randomly assigned to receive either placebo or ganciclovir (5 mg per kilogram of body weight twice a day for one week, followed by 5 mg per kilogram per day) for the first 100 days after transplantation. Patients were followed for the development of biopsy-confirmed CMV disease, ganciclovir-related toxicity, and survival. RESULTS. Between assignment to the study drug and day 100 after transplantation, CMV disease developed in only 1 of the 37 patients assigned to receive ganciclovir (3 percent), but in 15 of the 35 patients assigned to receive placebo (43 percent, P less than 0.00001). The ganciclovir recipients had rapid suppression of virus excretion; 85 percent had negative cultures after one week of treatment, as compared with 44 percent of the placebo group (P = 0.001). The principal toxic reaction was neutropenia; 11 ganciclovir recipients had an absolute neutrophil count below 0.75 x 10(9) per liter, as compared with 3 placebo recipients (P = 0.052). Treatment was discontinued in 11 ganciclovir recipients and 1 placebo recipient because of neutropenia (P = 0.003). After treatment was stopped, the neutrophil count recovered in all patients. Overall survival was significantly greater in the ganciclovir group than in the placebo group both 100 days and 180 days after transplantation (P = 0.041 and 0.027, respectively). CONCLUSIONS. Early treatment with ganciclovir in patients with positive surveillance cultures reduces the incidence of CMV disease and improves survival after allogeneic bone marrow transplantation.  相似文献   
5.
Two types of experiments concerning estimated magnitude of self-motion during exposure to linear oscillation on a parallel swing are described in this paper. Experiment I examined changes in magnitude estimation as a function of variation of the subject's head orientation, and Experiments II a, II b, and II c assessed changes in magnitude estimation performance following exposure to sustained, "intense" linear oscillation (fatigue-inducing stimulation). The subjects' performance was summarized employing Stevens' power law (R = k . Sn, where R is perceived self-motion magnitude, k is a constant, S is amplitude of linear oscillation, and n is an exponent). The results of Experiment I indicated that the exponents, n, for the magnitude estimation functions varied with head orientation and were greatest when the head was oriented 135 degrees off the vertical. In Experiments II a-c, the magnitude estimation function exponents were increased following fatigue. Both types of experiments suggest ways in which the vestibular system's contribution to a spatial orientation perceptual system may vary. This variability may be a contributing factor to the development of pilot/astronaut disorientation and may also be implicated in the occurrence of motion sickness.  相似文献   
6.
Endoscopic techniques are now an accepted part of the surgical armamentarium and are used routinely in a number of aesthetic and reconstructive procedures. Endoscopic techniques are now being used commonly by plastic surgeons in forehead and face lifts. In both craniofacial surgery and in neurosurgery, the application of endoscopy potentially allows the surgical team to perform wide dissection of the dura mater in a minimally invasive fashion, thereby potentially reducing the risk of dural and brain injury. Also reduced by this surgical approach is potential injury to the major venous structures, such as the sagittal sinus, along with overall reduced bleeding. After an extensive laboratory study of 10 cadaveric dissections, the authors have refined a new endoscopic technique for completing an endoscopic intracranial craniofacial osteotomy. This study was conducted in the Department of Pathology at the University of Brno (Czech Republic), and was performed as a cooperative multicenter project between the University of Palermo, the Albert Einstein College of Medicine/ Montefiore Medical Center, the Hospital Infantil de Mexico, "Federico Gomez," and the Medtronic Midas Rex Institute, (Fort Worth, TX). During this cadaveric anatomic study and using small trephinations and skin incisions the authors were able to develop several different craniofacial and endoscopic monobloc procedures. To accomplish intracranial and facial osteotomies, a new malleable high-speed drill was designed for use in the endoscopic craniofacial approach. Using these newly developed cadaveric techniques and instrumentation, the authors performed two intracranial craniofacial procedures on children with congenital craniofacial anomalies. There would appear to be several significant advantages for the craniofacial patient as result of these new techniques: reduced surgical trauma, operative bleeding, surgical time, and hospitalization, along with a reduced risk of infection. It became quickly apparent, as a result of these cadaveric studies, that the learning curve for this endoscopic procedure is quite steep. Tutino M, Chico F, Tutino M, Goodrich JT, Ortiz Monasterio F. Endoscopic intracranial craniofacial and monobloc osteotomies with the aid of a malleable high-speed pneumatic drill: a cadaveric and clinical study.  相似文献   
7.
The purpose of this work was to compare intracranial magnetic resonance angiography (MRA) image quality using three different radiofrequency coils. The three coil types included a reduced volume quadrature birdcage coil with endcap, a commercially available quadrature birdcage head coil, and a four-element phased-array coil. Signal-to-noise ratio (SNR) measurements were obtained from comparison studies performed on a uniform cylindrical phantom. MRA comparisons were performed using data acquired from 15 volunteers and applying a thick-slab three-dimensional time-of-flight sequence. Analysis was performed using the signal difference-to-noise ratio, a quantitative measure of the relative vascular signal. The reduced-volume endcap and phased-array coils, which were designed specifically for imaging the intracranial volume of the head, improved the image SNR and vascular detail considerably over that obtained using the commercially available head coil. The endcap coil configuration provided the best vascular signal overall, while the phased-array coil provided the best results for arteries close to the coil elements.  相似文献   
8.
Modification of the epigenome may be a mechanism underlying toxicity and disease following chemical exposure. Animal and human data suggest that mercury (Hg) impacts DNA methylation. We hypothesize that methylmercury and inorganic Hg exposures from fish consumption and dental amalgams, respectively, may be associated with altered DNA methylation at global repetitive elements (long interspersed elements, LINE‐1) and candidate genes related to epigenetic processes (DNMT1) and protection against Hg toxicity (SEPW1, SEPP1). Dental professionals were recruited at Michigan Dental Association (MDA) meetings in 2009 and 2010. Subjects (n = 131) provided survey data (e.g. exposure sources, demographics) and biological samples for Hg measurement and epigenetic analysis. Total Hg was quantified via atomic absorption spectrophotometry in hair and urine, indicative of methylmercury and inorganic Hg exposures, respectively. Global repetitive and candidate gene methylation was quantified via pyrosequencing of bisulfite converted DNA isolated from buccal mucosa. Hair Hg (geometric mean (95% CI): 0.37 (0.31–0.44) µg/g) and urine Hg (0.70 (0.60–0.83) µg/L) were associated with sources of exposure (fish consumption and dental amalgams, respectively). Multivariable linear regression revealed a trend of SEPP1 hypomethylation with increasing hair Hg levels, and this was significant (P < 0.05) among males. The trend remained when excluding non‐dentists. No significant relationships between urine Hg and DNA methylation were observed. Thus, in a limited cohort, we identified an association between methylmercury exposure and hypomethylation of a potentially labile region of the genome (SEPP1 promoter), and this relationship was gender specific. Environ. Mol. Mutagen. 54:195–203, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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