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71.
Brown  PB; Zwiebel  WJ; Call  GK 《Radiology》1989,170(2):541-543
Duplex ultrasound (US) scans of 110 carotid arteries ipsilateral to hemispheric strokes were compared with scans of 90 asymptomatic vessels in the same patients to determine the relative prevalence of stenotic lesions. In addition, scans of paired carotid arteries in patients with stroke involving only one cerebral hemisphere were compared to determine whether the incriminated side demonstrated a greater degree of stenosis than the asymptomatic side. The duplex US findings demonstrated a positive correlation between stenosis and hemispheric stroke. However, only 20% of carotid arteries ipsilateral to hemispheric stroke showed a reduction in diameter greater than 70%, compared with 5% of asymptomatic vessels. A minimal difference was demonstrated between the symptomatic and asymptomatic groups with respect to lesser degrees of stenosis. In paired carotid arteries, the degree of stenosis of the symptomatic vessel exceeded that of the asymptomatic vessel in only 43% of cases. These results suggest that the prevalence of severe carotid stenosis in stroke patients has been previously overestimated. The findings also emphasize the need for further investigation of other plaque-related risk factors that may enhance stroke prevention through improved selection of surgical or medical therapy. Factors currently under investigation include plaque ulceration, intraplaque hemorrhage, plaque echogenicity, and the effects of sequential stenoses.  相似文献   
72.
OBJECTIVE: To study Vβ gene expression in oral lichen planus (OLP) lesional T lymphocyte cell lines.
MATERIALS AND METHODS: Lesional T lymphocytes were isolated from eight OLP patients and cell lines established. The total RNA was extracted from these lymphocyte cell lines and reverse transcribed. cDNA was amplified by the polymerase chain reaction (PCR) using a panel of 26 Vβ-specific oligonucleotide primers followed by qualitative analysis of the electrophoresed reaction products.
RESULTS: Vβ 1, 2, 3, 5.1, 6.1–3, 7, 8, 9, 22. 23, and 24 were represented consistently in all of the OLP samples, Vβ11, 12, and 17 were consistently negative, while the other Vβ families (Vβ4, 5.2–3, 10, 13.1, 13.2, 14, 15, 16, 18, 19, 20, and 21) were variable. Vβ22 and 23 were the most strongly expressed in all patients.
CONCLUSIONS A limited T cell receptor (TCR) gene usage indicates a degree of oligoclonality within these lesional T lymphocyte cell lines from OLP. This implies that OLP may be an antigen-specific disease or linked to a limited number of superantigens.  相似文献   
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Tabar  L; Pentek  Z; Dean  PB 《Radiology》1981,141(3):659
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Disparities in health and medical conditions among ethnic and racial groups have been repeatedly documented. These inequalities, which have been noted in the recent past, include health outcomes such as quality of life and mortality, process, accessibility and appropriateness of care, and the prevalence of certain degenerative conditions and infectious diseases. Syphilis, a sexually transmitted disease (STD) which seemed to have disappeared or had been controlled over the years, has now re-emerged as a major public health problem in many rural, urban and suburban communities. Progression of the current rate of syphilis, which erupted in Baltimore during the later part of 1994, has continued unabated, most especially among the ethnic minorities, despite efforts of the Baltimore City Health Department and Maryland Department of Health and Mental Hygiene to control the epidemic. With the current incidence rates of 270 per 100 000 live births for congenital syphilis and 99.3 per 100 000 population for primary, secondary and latent syphilis (96% of the cases being in the non-white population), Baltimore becomes the city with the highest number of syphilis cases in the nation, surpassing the national average of 2.6 cases per 100 000 population. This study, which utilizes a combination of retrospective and questionnaire-oriented approach, was designed to assess factors that influenced the high incidence of syphilis among Baltimore inner-city dwellers between 1994 and 1998. Data for the study included syphilis reports from private physicians, the Baltimore City Health Department, STD clinics, the Center for Disease Control (CDC), and ethnographic interviews. Factors favoring the distribution and infectivity of the disease among the inner-city dwellers include greater poverty, high level of communication gaps between providers and a cross-section of minority inner-city dwellers, exchange of sex for crack cocaine, lower educational background, and inadequate and inappropriate health education/health promotion programs for the ethnic minorities.The paper calls for, among other things, culturally-sensitive and competent syphilis elimination/prevention health education and health promotion programs for the ethnic minority inner-city dwellers of Baltimore.  相似文献   
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Clinical Rheumatology - Rheumatoid arthritis (RA) is an inflammatory disease that leads to altered body composition. The loss of lean mass with a preservation or increase in fat mass has been...  相似文献   
80.
Pentoxifylline (PF) is used to enhance motility of spermatozoa from infertile human subjects. We have previously shown that 0.45 mM PF improved capacitation of spermatozoa and fertilization of oocytes in vitro in hamsters. The present study was carried out to assess PF- induced changes in motility kinematics of hamster spermatozoa by a computer-aided sperm analyser (CASA) and determine the timing of onset of hyperactivation (HA) and acrosome reaction (AR) in PF-treated spermatozoa. Motility kinematics were analysed by CASA for 0-8 h in the absence or presence of 0.45 mM PF in Tyrode's medium supplemented with lactate, pyruvate and polyvinyl alcohol (TLP-PVA) or in TLP-PVA with bovine serum albumin (TALP-PVA). Conventional assessment was also made on the percentage of motility and quality of motility of spermatozoa; values were expressed as sperm motility index (SMI). Both in TALP-PVA and TLP-PVA, PF markedly increased SMI, especially the quality of motility (P < 0.02) by 2-3 h which was sustained up to 6 h. The motility kinematic data of PF-treated spermatozoa in TALP-PVA showed that average path velocity, curvilinear velocity and amplitude of lateral head displacement significantly (P < 0.05) increased as early as 2 h, with the expected decrease in straightness (STR) and linearity (LIN). Similar changes were also observed with PF-treated spermatozoa in TLP-PVA. Moreover, the percentage of hyperactivated spermatozoa in PF-treated samples was significantly (P < 0.001) higher than the untreated control at 2 h. To determine whether PF could induce AR, independent of bovine serum albumin, quantitative AR was assessed by observing the presence or absence of acrosomal cap on viable spermatozoa. PF significantly (P < 0.001) increased the percentage of AR as early as 2 h, reaching maximum at 4 h both in TALP-PVA (P < 0.05) and in TLP-PVA (P < 0.001). These results show that, in hamsters, PF induces early onset (by 2 h) of HA and AR and increases the proportion of spermatozoa undergoing physiological maturation.   相似文献   
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