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931.
Hepatitis C virus shares amino acid sequence similarity with pestiviruses and flaviviruses as well as members of two plant virus supergroups. 总被引:55,自引:18,他引:55 下载免费PDF全文
R H Miller R H Purcell 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(6):2057-2061
Hepatitis C virus (HCV) is an important human pathogen that is associated with transfusion-related non-A, non-B hepatitis. Recently, HCV cDNA was cloned and the nucleotide sequence of approximately three-quarters of the virus genome was determined. A region of the predicted polyprotein sequence was found to share similarity with a nonstructural protein encoded by dengue virus, a member of the flavivirus family. We report here that HCV shares an even greater degree of protein sequence similarity with members of the pestivirus group (i.e., bovine viral diarrhea virus and hog cholera virus), which are thought to be distantly related to the flaviviruses. In addition, we find that HCV shares significant protein sequence similarity with the polyproteins encoded by members of the picornavirus-like and alphavirus-like plant virus supergroups. These data suggest that HCV may be evolutionarily related to both plant and animal viruses. 相似文献
932.
M B Leon Y Almagor A L Bartorelli L G Prevosti P S Teirstein R Chang D L Miller P D Smith R F Bonner 《Circulation》1990,81(1):143-155
In 12 patients (aged 64 +/- 10 years) with femoropopliteal occlusions (1-27 cm; average, 8.4 cm length) that could not be recanalized by standard guidewire-balloon angioplasty techniques, percutaneous laser-assisted balloon angioplasty was performed by use of a new fluorescence-guided dual-laser system. Plaque detection by 325-nm laser-excited fluorescence spectroscopy provided real-time feedback control to a 480-nm pulsed dye laser (2-microseconds pulses) for atheroma ablation. By means of a common 200-microns optical fiber, after diagnostic fluorescence sensing, computer algorithms directed a fire or no-fire signal (5 Hz) to the treatment laser for selective plaque removal. Laser recanalization (15-50 mJ/pulse) was successful in 10 of 12 patients; this procedure was followed by definitive balloon angioplasty in seven of 12 patients with increased ankle/arm indexes (from 0.60 +/- 0.12 at baseline to 0.84 +/- 0.11 after treatment, p = 0.0043). In laser and balloon angioplasty failures, all femoropopliteal occlusions were heavily calcified, and there were two mechanical guidewire perforations without clinical sequelae. Ablation of calcified lesions required higher pulse energies and greater total energy per centimeter of recanalized tissue (1,837 +/- 1,251 mJ/cm vs. 90 +/- 39 mJ/cm, p = 0.0036). Fluorescence spectroscopy (n = 219 sites) was helpful in flush occlusions and correctly identified plaque, underlying media, and thrombus by changes in fluorescence intensity, shape, and peak position. Thus, when fluorescence-guided laser angioplasty was used in a subgroup of patients refractory to standard angioplasty techniques, primary recanalization and subsequent balloon angioplasty of femoropopliteal occlusions was successful in 83% and 58% of the patients, respectively. Importantly, treatment of heavily calcified lesions accounted for all of the failures and will require modified delivery systems to create larger primary channels and to increase catheter-tip control, which should improve clinical results in the future. 相似文献
933.
Selection of benign primitive hematopoietic progenitors in chronic myelogenous leukemia on the basis of HLA-DR antigen expression. 总被引:6,自引:2,他引:6
Chronic myelogenous leukemia (CML) is a lethal malignancy of the human hematopoietic stem cell. Here we report that coexistent benign, primitive hematopoietic progenitors can be distinguished from their malignant counterparts in CML bone marrow by differences in cell surface antigen expression. Selection of bone marrow cells expressing the CD34 antigen but lacking the HLA-DR antigen results in recovery of small lymphocyte-like blasts, which initiate and sustain production of myeloid clonogenic progeny in vitro. Secondary clonogenic cells derived at week 1, 5, and 8 from long-term bone marrow cultures (LTBMCs) initiated with primitive progenitors, which lack HLA-DR antigens, exhibit neither the Philadelphia chromosome (Ph1) nor the corresponding bcr/abl mRNA characteristic of CML. In contrast, clonogenic cells recovered at week 1, 5, and 8 from LTBMCs initiated with the CML HLA-DR+ population contain Ph1 and express bcr/abl mRNA. This observation indicates that it may be possible to select a population of viable, exclusively benign hematopoietic stem cells from CML bone marrow capable of repopulating the hematopoietic compartment following autologous bone marrow transplantation. 相似文献
934.
Gupta V Yesilbursa D Huang WY Aggarwal K Gupta V Gomez C Patel V Miller AP Nanda NC 《Echocardiography (Mount Kisco, N.Y.)》2008,25(2):217-227
BACKGROUND: Patent foramen ovale (PFO) is a well-recognized risk factor for ischemic strokes. The true prevalence of PFO among stroke patients is still under debate. Transesophageal echocardiography (TEE) is the "gold standard" in diagnosing PFO but the physiology requires right-to-left atrial shunting. In this report, we evaluate the prevalence of PFO in a diverse group of ischemic stroke patients studied by TEE. METHODS: TEE of 1,663 ischemic stroke patients were reviewed for cardiac source of embolism, including PFO and atrial septal aneurysm (ASA). Agitated saline bubble injection was performed to look for right to left atrial shunting. Success of maneuvers to elevate right atrial pressure (RAP) was noted by looking at the atrial septal bulge. RESULTS: Among 1,435 ischemic stroke patients analyzed, the presence or absence of PFO could not be determined in 32.1% because bulging of the septum could not be demonstrated in patients with negative contrast study despite aggressive maneuvers to elevate RAP. Of the remaining 974 patients, 294 patients (30.2%) had a PFO. The mean age was 61.5 years in both groups, with a bimodal distribution of PFO and the highest prevalence occurring in < or =30-year-old group. Prevalence of PFO was similar in men (32.4%) and women (28.15%, P = 0.15); and in Caucasian (32.1%) and African American (27.7%; P = 0.15). ASA was present in 2.02% and hypermobile septum in 2.49% of the 1,435 patients. PFO was seen in 79.3% of the patients with ASA. CONCLUSION: Successful elevation of RAP cannot be achieved in a significant number of patients undergoing TEE and determination of PFO may be difficult. In our series, the true prevalence of PFO among ischemic stroke patients was 30.2% taking into account only those patients who showed no shunting despite bulging of the atrium septum into the left atrium (PFO absent group) during the contrast study. There was no gender or racial difference in the prevalence of PFO, but there was a bimodal distribution in prevalence with age. 相似文献
935.
Sexual transmission risk among noninjecting heroin users infected with human immunodeficiency virus or hepatitis C virus. 总被引:6,自引:0,他引:6
A Neaigus M Miller S R Friedman D C Des Jarlais 《The Journal of infectious diseases》2001,184(3):359-363
To assess whether human immunodeficiency virus (HIV)-infected and/or hepatitis C virus (HCV)-infected noninjecting heroin users (NIUs) are a potential sexual transmission bridge to "lower risk" partners, 180 HIV- or HCV-infected NIUs recruited in New York City were interviewed about their sexual behaviors and partnerships. Sixty-two percent were former injecting drug users (IDUs). Partners reported not to be HIV infected, IDUs, or men who have sex with men were defined as lower risk. Among 54 HIV-infected NIUs, lower risk partners were reported by 54% of never IDUs and 23% of former IDUs (P=.02). Among 155 HCV-infected NIUs, lower risk partners were reported by 54% of never IDUs and 45% of former IDUs (not significant). Engaging in unprotected vaginal or anal sex and having lower risk partners was reported by 29% of HIV-infected never IDUs, 12% of HIV-infected former IDUs, 29% of HCV-infected never IDUs, and 34% of HCV-infected former IDUs. HIV-infected NIUs, particularly never IDUs, and, possibly, HCV-infected NIUs, are a potential sexual transmission bridge. 相似文献
936.
Carolina Loria Jennifer A. Domm Natasha B. Halasa Elizabeth Heitman E. Kathryn Miller Meng Xu Benjamin R. Saville Haydar Frangoul John V. Williams 《Pediatric transplantation》2015,19(1):94-100
Children with cancer and HSCT recipients are at high risk for common viral infections. We sought to define the viral etiology of ARI and identify risk factors. Nasal wash samples were collected from pediatric hematology–oncology patients and HSCT recipients with ARI during the 2003–2005 winter seasons. Real‐time RT‐PCR was performed to detect Flu A, influenza B, RSV, PIV 1‐3, human MPV, and HRV. HRV specimens were sequenced and genotyped. Seventy‐eight samples from 62 children were included. Viruses were detected in 31 of 78 samples (40%). HRV were detected most frequently, in 16 (52%) including five HRVC; followed by seven (22%) RSV, five (16%) Flu A, four (13%) MPV, and two (6%) PIV2. There was a trend toward higher risk of viral infection for children in day care. Only 8% of the study children had received influenza vaccine. HRV, including the recently discovered HRVC, are an important cause of infection in pediatric oncology and HSCT patients. Molecular testing is superior to conventional methods and should be standard of care, as HRV are not detected by conventional methods. 相似文献
937.
PURPOSE: The purpose of this study is to expand knowledge regarding end-of-life care received in nursing homes through the use of narrative interviews with family members close to the decedents. DESIGN AND METHODS: We conducted follow-up qualitative interviews with 54 respondents who had participated in an earlier national survey of 1,578 informants. Interviews were taped and transcribed and then coded by a five-member, multidisciplinary team to identify overarching themes. RESULTS: Respondents report that the needs of dying patients are often insufficiently addressed by health care professionals. Their low expectations of nursing homes and their experiences cause many to become vigilant advocates. Respondents report that physicians are often "missing in action," and they desire more and better trained staff. They indicate that regulations reinforce task-focused rather than person-centered care and add to patient and family burden. Although hospice services are reported to enhance end-of-life care, respondents also report late referrals and occasional misunderstandings about the role and scope of hospice. IMPLICATIONS: Sustained efforts on many fronts are needed to improve end-of-life care in nursing homes. Policy recommendations are suggested. 相似文献
938.
Miller DD 《Current cardiology reports》2004,6(1):41-52
More than a decade of dramatic changes in US and global health care has affected the practice of and payment for nuclear cardiology
services. The clear diagnostic and prognostic power of nuclear cardiology procedures to detect coronary artery disease and
predict patient outcomes has resulted in the rapid growth of these procedures in clinical practice. This has focused the attention
of public and private payers on the high use of medical resources required to carry out nuclear cardiology testing. Two recent,
major multicenter trials, one in the United States and another in Europe, have demonstrated the cost effectiveness of stress
myocardial perfusion imaging strategies compared with coronary angiography in patients with known or suspected coronary artery
disease, across the spectrum of pretest risks and both sexes. These studies, and more extensive data from more than 10 years
of decision analysis, have reinforced the value of nuclear cardiology in modern cardiovascular health care. Future challenges
will include assurance of provider and laboratory quality in the burgeoning outpatient imaging centers across the country,
and wider acceptance by payers and expert panels of the evidence supporting the cost effectiveness of nuclear cardiology in
most clinical settings. 相似文献
939.
Selim AJ Fincke G Berlowitz DR Miller DR Qian SX Lee A Cong Z Rogers W Selim BJ Ren XS Spiro A Kazis LE 《The journals of gerontology. Series A, Biological sciences and medical sciences》2005,60(4):515-519
BACKGROUND: Information on the health status of centenarians provides a means for understanding the health care needs of this growing population. Therefore, we examined the health status of a national cohort of centenarian veteran enrollees. METHODS: Ninety-three centenarian veteran enrollees returned a complete health history questionnaire, which included questions about sociodemographic information, age-associated conditions, health behaviors, health-related quality of life as measured by the Veterans SF-36, and change in health status. RESULTS: Centenarian veteran enrollees are a group with major impairment across multiple dimensions of health-related quality of life despite having a relatively low prevalence of diseases. They had considerable physical limitations as reflected by their physical health summary scores (26.2 +/- 8.3). However, their mental health was comparatively good (mental health summary score 44.1 +/- 12.5). Compared to younger elderly veterans (ages 85-99), centenarians had a lower prevalence of hypertension, angina or myocardial infarction, diabetes, and chronic low back pain (p <.05). Centenarians had significantly worse physical functioning, role physical, vitality, and social functioning scores than did younger elderly veterans. The two groups did not differ in their general health, bodily pain, role emotional, and mental health scores. Centenarians did not perceive much decline in their physical or mental health during the preceding year. CONCLUSIONS: Centenarian veteran enrollees are a group with a low number of age-associated diseases and good mental health despite substantial physical limitations. These results support future studies of services directed toward improvement of function as opposed to those focused solely on the treatment of diseases. 相似文献
940.
A Miller B Arthurs A Boucher A Liberman N Bernard P Rodien M Salvi J R Wall 《Thyroid》1992,2(3):197-202
SDS-polyacrylamide gel electrophoresis and Western blotting for antibodies reactive with a 64 kDa protein in pig eye muscle membrane was carried out in patients with lid lag and retraction, but no other signs of ophthalmopathy, associated with thyroid disease or nonimmunologic goiter and in patients with Graves' hyperthyroidism without ophthalmopathy who were studied prospectively to determine the relationship of eye muscle antibodies to clinical features of the ophthalmopathy as they appeared in this group of predisposed patients. Seventy-one percent of euthyroid patients with lid lag and retraction but no established ophthalmopathy had detectable serum antibodies to a 64 kDa eye muscle membrane protein. Much smaller proportions had antibodies to proteins of other MW. In normal subjects with previously detectable antibodies to a 64 kDa protein, serum titers, determined by carrying out immunoblotting at serum dilutions of 1:25-1:6400, were low (< or = 1:100) in all cases tested. On the other hand, titers were higher (1:200-1:6400) in 16 of 22 patients with established ophthalmopathy and in 5 of 7 patients with lid lag and retraction tested. Titers tended to be lower in patients with ophthalmopathy of > or = 3 years duration than in those of < or = 1 year duration. Antibody titers were low (1:25) in 6 of 7 patients with Graves' hyperthyroidism without evident eye disease tested. Antibodies to a 64 kDa eye muscle membrane protein were predictive of the development of ophthalmopathy in patients with Graves' hyperthyroidism studied prospectively for periods of 8-42 months.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献