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51.
We report 2 cases of B-cell lymphoma of the thyroid in which although a marginal zone distribution of the neoplastic cells was present, the cytologic features of the cells indicated large cell lymphoma. One of the cases showed an accumulation of crystalline inclusions within the cytoplasm of the neoplastic cells. Many of these inclusion-bearing cells showed plasmacytoid features. By immunohistochemical studies performed on formalin-fixed paraffin-embedded tissue, both of the cases showed a B-cell phenotype as indicated by CD20 expression, and 1 showed kappa light chain restriction. In both cases, Ki-67 staining corroborated the impression of an aggressive neoplasm with staining of 50% and 90% of the tumor cells. Both patients received cyclophosphamide, doxorubicin, vincristine, and prednisone with radiation therapy, and both are without evidence of disease after 17 and 18 months of follow-up. It is important to recognize this pattern of large B-cell lymphoma of the thyroid gland. While the indolent course typical of most low-grade extranodal marginal zone lymphomas is not likely in these cases, the outcome may be favorable if patients are treated aggressively with therapy for large cell lymphoma.  相似文献   
52.
The purpose of the present study was to determine the frequency in which antibody reactive to Ureaplasma urealyticum could be detected in a population of pregnant women and newborn infants. Serum samples from a prospective cohort of 80 healthy, U. urealyticum culture-positive and culture-negative pregnant women and a retrospective cohort of 522 infants born at between 25 and 42 weeks of gestation were studied by immunoblot analysis. Cultures of specimens from the lower genital tract were positive for U. urealyticum for 83% of the pregnant women, and serum immunoglobulin G (IgG) antibody which reacted to U. urealyticum was detectable in 93% of the pregnant women. Samples from five women (8%) had increases in the number of anti-U. urealyticum IgG bands over the course of the pregnancy. Samples from four of these five women had corresponding increases in the number of antibody bands present in IgA immunoblots. Six of the 522 samples from newborns or cord blood (1.1%) were positive for anti-U. urealyticum IgA; 5 of these 6 samples were also positive for IgM. The six anti-U. urealyticum IgA-positive infants were distributed as follows; 3 of 67 (4.5%) infants were delivered at 25 to 30 weeks of gestation, 3 of 176 (1.7%) infants were delivered at 31 to 34 weeks of gestation, and 0 of 279 infants were delivered at > or = 35 weeks of gestation. An antibody response to U. urealyticum can be detected in pregnant women and preterm infants and may serve as a marker of infection.  相似文献   
53.
54.
ContextExercise-related lower leg pain (ERLLP) is common in runners.ObjectiveTo compare biomechanical (kinematic, kinetic, and spatiotemporal) measures obtained from wearable sensors as well as lower extremity alignment, range of motion, and strength during running between runners with and those without ERLLP.DesignCase-control study.SettingField and laboratory.Patients or Other ParticipantsOf 32 young adults who had been running regularly (>10 mi [16 km] per week) for ≥3 months, 16 had ERLLP for ≥2 weeks and 16 were healthy control participants.Main Outcome Measure(s)Both field and laboratory measures were collected at the initial visit. The laboratory measures consisted of alignment (arch height index, foot posture index, navicular drop, tibial torsion, Q-angle, and hip anteversion), range of motion (great toe, ankle, knee, and hip), and strength. Participants then completed a 1.67-mi (2.69-km) run along a predetermined route to calibrate the RunScribe devices. The RunScribe wearable sensors collected kinematic (pronation excursion and maximum pronation velocity), kinetic (impact g and braking g), and spatiotemporal (stride length, step length, contact time, stride pace, and flight ratio) measures. Participants then wore the sensors during at least 3 training runs in the next week.ResultsThe ERLLP group had a slower stride pace than the healthy group, which was accounted for as a covariate in subsequent analyses. The ERLLP group had a longer contact time during the stance phase of running (mean difference [MD] = 18.00 ± 8.27 milliseconds) and decreased stride length (MD = −0.11 ± 0.05 m) than the control group. For the clinical measures, the ERLLP group demonstrated increased range of motion for great-toe flexion (MD = 13.9 ± 4.6°) and ankle eversion (MD = 6.3 ± 2.7°) and decreased strength for ankle inversion (MD = −0.49 ± 0.23 N/kg), ankle eversion (MD = −0.57 ± 0.27 N/kg), and hip flexion (MD = −0.99 ± 0.39 N/kg).ConclusionsThe ERLLP group exhibited a longer contact time and decreased stride length during running as well as strength deficits at the ankle and hip. Gait retraining and lower extremity strengthening may be warranted as clinical interventions in runners with ERLLP.  相似文献   
55.
This study examined two groups of people who were pursuing treatment for obesity: either medical intervention (a hospital group; N = 20) or support for dietary restriction (a community group; N = 18). This study addressed four questions: (1) Were there differences between the two groups in terms of their psychological distress (as measured by the Symptom Checklist)? (2) Does binge eating moderate psychological distress? (3) Do feelings of ineffectiveness moderate psychological distress? and (4) Which variables best accounted for group membership (i.e., type of treatment sought)? Results suggested that the hospital group was significantly more distressed than the community group. However, there were no differences between the two groups with respect to binge eating or feelings of ineffectiveness. These findings suggest that it is the effects of morbid obesity that are most likely to moderate psychological distress.  相似文献   
56.
Native horseradish peroxidase (HRP) is known to pass rapidly through glomeruli when injected into rats. We have found that a conjugate of HRP with poly-lysine is readily endocytosed by glomerular epithelial cells (GEC). We have used this conjugate to study the GEC endocytotic process in male Wistar rats. The conjugate has an approximate molecular weight of 55-58,000, a pI of greater than 10.0, and almost the same secondary conformation as HRP; it does not increase urinary protein excretion significantly or alter the morphology of the renal glomeruli. After intravenous injection of the conjugate, it could be found in the GBM from 1 min to 4 h. At 1 min, it was evenly distributed on GEC foot processes and plasma membrane. GEC start to take up the conjugate from 1 min post-injection, by cellular membrane invagination. This reached a maximum at 4 h. Some of the endocytosed conjugate passed to lysosomes from the endosomal system. The amount of peroxidase demonstrable in the glomerular epithelial cells was considerably reduced by 24 h.  相似文献   
57.
We have evaluated, both clinically and by linkage analysis, a large family with 22 known affected males with the MASA syndrome (McKusick 303300). Clinical findings varied widely amongst the affected family members, with some appearing initially to have the MASA syndrome and others to have X-linked hydrocephalus (HSAS) (McKusick 307000). Important findings included the presence of adducted thumbs in two obligate carriers, learning problems or mild mental retardation in three females, two of whom were obligate carriers, and hydrocephalus with neonatal death in three females born to obligate carriers. X-inactivation analysis in lymphocytes from the two women with adducted thumbs revealed preferential inactivation of one X chromosome, suggesting that nonrandom X-inactivation may be responsible for clinical expression in females. The presence of HSAS in some individuals of this family and the MASA syndrome in others further supports the hypothesis that these two conditions are the result of a mutation in the same gene.  相似文献   
58.
Advances in genetic technology are increasing the availability of genetic tests, not only for rare single gene disorders, but also for common diseases such as breast and colo-rectal cancer. Before there can be widespread uptake of these tests, they must be evaluated to confirm the benefits of their use. But how should genetic tests be evaluated, given the speed at which new tests are emerging? One highly influential approach is the analytic validity, clinical validity, clinical utility and ethical, legal and social issues (ACCE) framework, which has provided a benchmark for the evaluation of genetic tests. The approach has been adopted and adapted by the United Kingdom Genetic Testing Network, with the help of the Public Health Genetics Unit in Cambridge, to evaluate new genetic tests for use in the National Health Service. We discuss a number of conceptual, methodological, and practical issues concerning the evaluation of genetic tests, based on lessons learned from applying the ACCE framework and from the UK experience, and make a number of recommendations to further strengthen the evaluation of genetic tests.  相似文献   
59.
Purified preparations of TYMV contain a number of minor nucleoprotein components distinguishable on the basis of their density in CsCl gradients (R. E. F. Matthews, Virology12, 521–539, 1960). When analysed by polyacrylamide-gel eletrophoresis, the RNA from each of these various components was found to consist of a characteristic set of molecular-weight species. Full-size RNA (2 × 106 daltons) was present only in nucleoproteins B1 and B2. Nucleoproteins B0, B00, and B000 contained RNAs ranging in size from approx 1.3 to 0.28 × 106 daltons. The 0.28 × 106-dalton RNA species was detectable in all nucleoprotein fractions, but was a significant proportion of the RNAs of B000 and B00. Translation of the RNA from each of the nucleoproteins in the wheat germ cell-free protein synthesizing system yielded essentially similar patterns of polypeptides which ranged in size from 5000 to 70,000 daltons. The major radioactive product migrated on SDS-polyacrylamide gels to the same position as TYMV coat protein. The data suggest that the 0.28 × 106-dalton RNA component is the cistron for coat protein, and that it and other RNAs associated with TYMV infection are encapsidated.  相似文献   
60.
AIMS--In April 1991 an internal quality assessment scheme (IQAS) was introduced into the virology section of the Clinical Microbiology and Public Health Laboratory, Cambridge. The IQAS was established to identify recurring technical and procedural problems, to check the adequacy of current techniques, and to calculate the frequency of errors. METHODS--Between April 1991 and December 1993, 715 anonymous clinical serum samples were submitted to the laboratory to test 3245 individual procedures of diagnostic viral serology. RESULTS--A total of 485 (14.9%) procedural and 61 (1.9%) technical discrepancies were observed, the technical discrepancies mainly being recorded in complement fixation tests. Twenty two (0.7% of total procedures) of the technical discrepancies were diagnostically significant. CONCLUSIONS--Evaluation criteria developed with the introduction of IQAS to viral serology, and technical and procedural discrepancies are assessed. As yet, IQAS has not been introduced to other sections of the diagnostic virology laboratory (virus isolation, electron microscopy, immunofluorescence, and enzyme linked immunosorbent assays for viral and chlamydial antigens).  相似文献   
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