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821.
Background : DNA profiles from variable number of tandem repeat (VNTR) loci typically are composed of two bands, one derived from each member of the homologous pair of chromosomes. DNA profiles composed of more than two bands result from mutations, and the uestion arises as to the mechanism underlying these unusual multibanded DNA profiles. Study Design and Methods : An alleged father in a paternity test was found to have a five-banded DNA profile at the D10S28 locus when his DNA was subjected to single-locus restriction fragment length polymorphism mapping with the restriction enzyme Pvu II. Results : Several results suggest that this complex DNA profile is the result of several single change within the VNTR locus First, there was no evidence of partial digestion of the DNA with Pvu II. Furthermore, the multibanded allele happened, in this case, to be transmitted to the child, who also showed a five-banded pattern composed of four bands inherited from the alleged father and one band inherited from the mother. Second, digestion of this DNA with Hae III resulted in the visualization of just two bands at the D10S28 locus. Conclusion : The results confirm the notion that mutations at VNTR loci are not always the result of additions or deletions of tandem repeats, but that they can also involve single-base substitutions either within or flanking VNTR loci that give rise to atypical DNA profiles and new alleles at the locus. single-base changes within or flanking VNTR loci that give rise to a typical DNA profiles and new alleles at the locus.  相似文献   
822.

Objectives

The aim of the study was to quantify the benefits (life expectancy gains) and risks (efavirenz‐related teratogenicity) associated with using efavirenz in HIV‐infected women of childbearing age in the USA.

Methods

We used data from the Women's Interagency HIV Study in an HIV disease simulation model to estimate life expectancy in women who receive an efavirenz‐based initial antiretroviral regimen compared with those who delay efavirenz use and receive a boosted protease inhibitor‐based initial regimen. To estimate excess risk of teratogenic events with and without efavirenz exposure per 100 000 women, we incorporated literature‐based rates of pregnancy, live births, and teratogenic events into a decision analytic model. We assumed a teratogenicity risk of 2.90 events/100 live births in women exposed to efavirenz during pregnancy and 2.68/100 live births in unexposed women.

Results

Survival for HIV‐infected women who received an efavirenz‐based initial antiretroviral therapy (ART) regimen was 0.89 years greater than for women receiving non‐efavirenz‐based initial therapy (28.91 vs. 28.02 years). The rate of teratogenic events was 77.26/100 000 exposed women, compared with 72.46/100 000 unexposed women. Survival estimates were sensitive to variations in treatment efficacy and AIDS‐related mortality. Estimates of excess teratogenic events were most sensitive to pregnancy rates and number of teratogenic events/100 live births in efavirenz‐exposed women.

Conclusions

Use of non‐efavirenz‐based initial ART in HIV‐infected women of childbearing age may reduce life expectancy gains from antiretroviral treatment, but may also prevent teratogenic events. Decision‐making regarding efavirenz use presents a trade‐off between these two risks; this study can inform discussions between patients and health care providers.  相似文献   
823.
Antigen receptor nonresponsiveness in chronic lymphocytic leukemia B cells   总被引:1,自引:4,他引:1  
B chronic lymphocytic leukemia (B-CLL) are clonal populations of mIgM+ or mIgM+/mIgD+ CD5+ B cells that appear to be arrested in the follicular mantle-zone B-cell stage. Functional analyses have shown two groups of B-CLL that can be distinguished based on their capacity to proliferate in response to B-cell antigen receptor complex (BCR) cross- linking. To investigate the molecular basis for this phenomenon, we have analyzed both architecture and functional properties of BCR complexes on these two groups of B-CLL. Both groups were found to express structurally similar BCR. However, protein tyrosine kinase (PTK) activity associated with and specific for BCR constituents was strongly diminished in nonresponsive B-CLL. Moreover, the PTK-dependent assembly of Shc/Grb2 complexes, which may couple the BCR to p21ras, was absent in these B-CLL. Finally, of all PTKs tested, the expression of PTK syk was found to be considerably lower in nonresponsive B-CLL. Thus, absence of mitogenic responses upon BCR cross-linking in particular B-CLL was found to be strictly correlated with diminished induction of BCR-associated PTK activity and lower levels of PTK syk. Because nonresponsive B-CLL closely resembles tolerant autoreactive B cells both functionally and biochemically, distinction between B-CLL with respect to functional properties in vitro may be determined by differences in antigen encounter in vivo.  相似文献   
824.
Ear piercing is becoming increasingly popular especially among children and adolescents. Up to one third of patients experienced some form of complication after ear piercing. The documented complications range from benign superficial infection to hypertrophic and keloid scarring to life-threatening staphylococcal sepsis and hepatitis. Buried earring is one of the many complications of ear piercing. It usually occurs after several weeks of piercing especially if it is related to the inflammatory process after piercing. Its incidence is also related to the use of a spring-loaded ear-piercing gun. Buried earring can easily be missed in children presenting with ‘missing’ earring, especially among the unsuspecting plastic trainee. We report a case of double buried earrings in each earlobe in a child with history of ‘missing’ earrings. This case highlights the need for vigilance especially in managing our young patient with ‘missing’ earrings and the benefit of a simple anteroposterior-view radiographic study in suspicious cases.  相似文献   
825.
We performed an analysis of prospectively-acquired cross sectional data on 106 Parkinson disease (PD) patients who underwent comprehensive neuropsychological testing and the Unified Parkinson Disease Rating Scale (UPDRS) motor scale. A significant correlation between the UPDRS motor and neuropsychological tests in all cognitive domains except for general intelligence and visuo-spatial function was seen. In this study, cognitive decline within this PD cohort correlated with motor impairment but not disease duration. Our findings suggest that overall cognitive impairment (except visuospatial dysfunction) may track motor progression in PD more than duration of disease. Longitudinal studies are needed to confirm our results.  相似文献   
826.
It is difficult to remove a large early gastric cancer (> or = 3 cm) in one-piece resection using conventional endoscopic mucosal resection. We tried to use an insulation-tipped (IT) diathermic knife to dissect these lesions. IT-endoscopic submucosal dissection (ESD) was performed in four aging patients with gastric malignancy. All lesions could be removed in one-piece resection by IT-ESD, although three of them exhibited remarkable fibrosis and ulceration. Three cases experienced curative treatment with IT-ESD after the pathologic evaluation, but it was not curative in one case because the pathology showed angiolymphatic invasion. This patient refused additional surgery in consideration of existing major systemic diseases. At 3 months to 1 year of follow-up, endoscopy showed no evidence of residual cancer. IT-ESD is effective in the treatment of large early gastric cancer and is an alternative treatment for early gastric cancer patients who are at risk for major operation.  相似文献   
827.
AIM: To examine the feasibility and validity of electronic generation of quality metrics in the intensive care unit (ICU). METHODS: This minimal risk observational study was performed at an academic tertiary hospital. The Critical Care Independent Multidisciplinary Program at Mayo Clinic identified and defined 11 key quality metrics. These metrics were automatically calculated using ICU DataMart, a near-real time copy of all ICU electronic medical record (EMR) data. The automatic report was compared with data from a comprehensive EMR review by a trained investigator. Data was collected for 93 randomly selected patients admitted to the ICU during April 2012 (10% of admitted adult population). This study was approved by the Mayo Clinic Institution Review Board. RESULTS: All types of variables needed for metric calculations were found to be available for manual and electronic abstraction, except information for availability of free beds for patient-specific time-frames. There was 100% agreement between electronic and manual data abstraction for ICU admission source, admission service, and discharge disposition. The agreement between electronic and manual data abstraction of the time of ICU admission and discharge were 99% and 89%. The time of hospital admission and discharge were similar for both the electronically and manually abstracted datasets. The specificity of the electronically-generated report was 93% and 94% for invasive and non-invasive ventilation use in the ICU. One false-positive result for each type of ventilation was present. The specificity for ICU and in-hospital mortality was 100%. Sensitivity was 100% for all metrics. CONCLUSION: Our study demonstrates excellent accuracy of electronically-generated key ICU quality metrics. This validates the feasibility of automatic metric generation.  相似文献   
828.
杨春娥  陈苏宁  王志睿 《医学争鸣》2005,26(22):2024-2024
0 引言高血压病是一种常见病和多发病,是心脑血管发病的重要危险因素,在我国其患病率仍呈上升趋势,严重威胁着人们的健康[1,2]. 我们对原发性高血压患者予以波依定(Plendil,即非洛地平缓释片,Felodipine extended release tablet)治疗,疗效满意.  相似文献   
829.
830.
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