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21.
To address concerns over the prevalence of silent (antibody-negative) infections among blood donors and high-risk populations, a combination of proviral amplification by polymerase chain reaction (PCR) and viral isolation by co-culture techniques was employed to resolve the human immunodeficiency virus type 1 (HIV-1) infection status of well-characterized groups of suspect blood donors and others identified in the blood bank setting. No silent infections were found in 65 follow-up samples from 26 persistently HIV-1-seroindeterminate blood donors, 16 persistently seronegative heterosexual partners of infected transfusion recipients, and 6 high-risk seronegative homosexual men identified through donor look-back investigations. In contrast, 21 seropositive controls tested positive. These results suggest a low prevalence of persistently silent infections in at-risk populations, even in high HIV prevalence regions. The PCR assay, with a co-detected internal positive control, and appropriate confirmatory algorithms, was found to be a useful direct assay to rule out infection, especially in concert with confirmatory virus isolation.  相似文献   
22.

Objective

To propose a centralized method for generating global unique identifiers to link collections of research data and specimens.

Design

The work is a collaboration between the Simons Foundation Autism Research Initiative and the National Database for Autism Research. The system is implemented as a web service: an investigator inputs identifying information about a participant into a client application and sends encrypted information to a server application, which returns a generated global unique identifier. The authors evaluated the system using a volume test of one million simulated individuals and a field test on 2000 families (over 8000 individual participants) in an autism study.

Measurements

Inverse probability of hash codes; rate of false identity of two individuals; rate of false split of single individual; percentage of subjects for which identifying information could be collected; percentage of hash codes generated successfully.

Results

Large-volume simulation generated no false splits or false identity. Field testing in the Simons Foundation Autism Research Initiative Simplex Collection produced identifiers for 96% of children in the study and 77% of parents. On average, four out of five hash codes per subject were generated perfectly (only one perfect hash is required for subsequent matching).

Discussion

The system must achieve balance among the competing goals of distinguishing individuals, collecting accurate information for matching, and protecting confidentiality. Considerable effort is required to obtain approval from institutional review boards, obtain consent from participants, and to achieve compliance from sites during a multicenter study.

Conclusion

Generic unique identifiers have the potential to link collections of research data, augment the amount and types of data available for individuals, support detection of overlap between collections, and facilitate replication of research findings.  相似文献   
23.
A new technique for percutaneous gastrostomy of a decompressed excluded gastric segment after Roux-en-Y gastric bypass (RYGBP) surgery is described and the results in a single institution are reviewed. Computed tomography guidance was used to place a 21- or 22-gauge needle into the lumen of the stomach and distend it to allow placement of a feeding catheter. Ten women underwent the procedure, and despite only three patients having clear access windows, gastrostomy placement was ultimately successful in all 10 patients. Percutaneous gastrostomy of the decompressed excluded gastric segment after RYGBP surgery can be challenging, but a high rate of success can be achieved.  相似文献   
24.
BACKGROUND: Peripheral blood progenitor cells (PBPCs) are commonly collected and used to reconstitute hematopoiesis after high-dose chemotherapy. However, strategies for optimal collection and assessment of leukapheresis components are not standardized. STUDY DESIGN and METHODS: Hematopoietic progenitor cell assays were performed on 369 leukapheresis components collected from 95 patients who had received doxorubicin-based chemotherapy and/or granulocyte-colony-stimulating factor (G-CSF). Precollection patient hematologic values, leukapheresis collection values, component hematopoietic progenitor cell assays, and patient outcome measures were summarized. The kinetics of mononuclear cell (MNC) and PBPC mobilization were assessed among four patient groups. RESULTS: Patient group was a significant predictor of the peripheral blood MNC count on the day of collection (p<0.0001), and that value was a significant predictor of granulocyte-macrophage– colony-forming unit (CFU-GM) yield (p<0.0001). This relationship between the peripheral blood MNC count on the day of collection and CFU- GM yield differed according to patient group (p<0.0001). CFU-GM made up a larger fraction of peripheral blood MNCs collected from patients who received chemotherapy plus G-CSF than collected from those who received G-CSF alone. Moreover, the peripheral blood MNC count and the corresponding CFU-GM yield increased significantly on consecutive days of collection in patient groups receiving chemotherapy and G-CSF but were unchanged or decreased in patients receiving G-CSF alone. CONCLUSION: The relationship between peripheral blood MNC count and leukapheresis component CFU-GM yield differed significantly between patients who received chemotherapy and G-CSF and those who received G- CSF alone for the mobilization of PBPCs. Patient peripheral blood MNC count and component CFU-GM yield are useful for both assessing and suggesting revisions to PBPC mobilization and collection strategies.  相似文献   
25.
Patients with acquired defects or congenital malformations of the palate exhibit disturbances in speech, including hypernasality, nasal emission, and decreased intelligibility of speech. Maxillofacial prosthetic treatment can reestablish the palatopharyngeal integrity to provide the potential for acceptable speech. This article describes a case series of patients with palatopharyngeal disorders and their treatment approaches.  相似文献   
26.
水体污染中常见致病菌的多重PCR分子检测研究   总被引:2,自引:0,他引:2  
[目的]建立同时检测沙门氏菌、志贺氏菌、绿脓杆菌、肠出血型大肠杆菌和副溶血弧菌等5种水体常见致病菌的多重PCR检测技术,为这些致病菌感染的快速诊断提供实验依据。[方法]筛选设计5对特异引物,建立优化的多重PCR扩增体系和条件。[结果]对5种致病菌的检测,多重PCR灵敏度分别为:肠出血型大肠杆菌O157102 cfu、志贺氏菌102 cfu、副溶血弧菌102 cfu、绿脓杆菌101 cfu、沙门氏菌102 cfu。应用于人工污染水样及天然水样的检测,均有清晰、特异的预期条带产生,并与传统检测结果一致,每个样品所需时间为6~8 h,相对于传统检测方法,极大地缩短了检测时间,提高了检测灵敏度。[结论]该方法适用于大通量样品的检测研究,可推广应用于食品检测、环境监测等领域。  相似文献   
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29.
Purpose:To report the prevalence, clinical profile, investigations, and visual outcomes of sarcoid intermediate uveitis in a tertiary eye care center in South India.Methods: Retrospective, observational case series. Records of 29 patients with sarcoid intermediate uveitis were retrieved. Complete ophthalmic evaluation and systemic examination by a pulmonologist with appropriate laboratory investigations were done. Results were analyzed using SPSS software.Results: Mean age group was 42.14 ± 11.31 years. The bilateral presentation was more common and females were more affected than males. Anterior chamber cells and flares in 22.4% of cases (N = 11 eyes), posterior synechiae in 20.4% (N = 10 eyes), and both small and mutton fat keratic precipitates in 14.2% of cases (N = 7 eyes) were noted; only one eye had Busacca nodules similar to other granulomatous uveitis. Cystoid macular edemas were present in three eyes. Treatment with oral steroids and systemic immunosuppression resulted in good visual recovery. The mean presenting visual acuity in right and left eye were 0.2 and 0.3, respectively. The mean final visual acuity in right and left eye was 0.1 and 0.3, respectively.Conclusion: Sarcoid intermediate uveitis is quite common in a tuberculosis endemic country like India. A complete review of systems with appropriate investigations is essential to prevent visual complications.  相似文献   
30.
To determine the incidence of transfusion-associated human immunodeficiency virus (HIV) infection after routine screening of donated blood, a pilot study estimated the pretransfusion prevalence of HIV infection among blood product recipients in San Francisco. Among the 911 nonduplicate pretransfusion specimens from recipients without a clinical history of acquired immune deficiency syndrome (AIDS) or AIDS-related complex (ARC), the overall prevalence of antibody to HIV was 2.9 percent (5.2% among males and 0.6% among females; p = 0.00002). If recipients in specifically defined or possible high-risk groups (n = 348) were excluded, a seropositivity rate of 1.8 percent (10/563) was detected, with all the positives occurring in men (10/242, 4.1%) and none in women (0/321, 0%). This demonstrated prevalence of HIV infection among blood product recipients in San Francisco before transfusion was substantially higher than the known 0.02 to 0.04 percent prevalence in the donor population. Therefore, the population of women without known risk for AIDS is the best in which to assess the risk of HIV infection in patients who are currently receiving seronegative blood transfusions.  相似文献   
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