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21.
BACKGROUND: Most blood centers utilize a confidential unit exclusion (CUE) process, intended to reduce the risk of transfusion-associated infectious diseases by allowing high-risk donors confidentially to exclude their blood from use for transfusion. The effectiveness of this method remains controversial. STUDY DESIGN AND METHODS: Confirmatory or supplemental test results for antibodies to human immunodeficiency virus, human T-lymphotropic virus type I, and hepatitis C virus, as well as hepatitis B surface antigen and syphilis and screening test results for antibodies to hepatitis B core (antigen) and alanine aminotransferase levels were obtained for approximately 1.8 million units donated during 1991 and 1992 at five blood centers within the United States. The prevalences of these infectious disease markers in units that the donors confidentially excluded (CUE+) and units that the donors did not exclude (CUE-) were calculated and examined within demographic subgroups. RESULTS: Units that were CUE+ were 8 to 41 times more likely to be seropositive for antibodies to human immunodeficiency virus and hepatitis C virus, hepatitis B surface antigen, and syphilis and three to four times more likely to react for antibody to hepatitis B core (antigen) or to have elevated alanine aminotransferase levels than units that were CUE- (p < 0.001). The positive predictive value of CUE (the percentage of CUE+ units that were confirmed seropositive for any marker) was 3.5 percent, and the sensitivity of CUE (the percentage of confirmed-seropositive units that were CUE+) was 2.3 percent. CONCLUSION: The current CUE process has low sensitivity and apparently low positive predictive value, and in many cases, it appeared that donors misunderstood it. Yet, CUE was not a “random process,” as CUE+ units were more likely to be seropositive for any infectious disease marker than CUE- units. This suggests that efforts to improve the CUE system may be warranted. As risk factors for transfusion-transmitted infection become more difficult to identify by history-based screening, however, such efforts may have limited effect.  相似文献   
22.

Background  

During the SARS pandemic in Hong Kong, panic and worry were prevalent in the community and the general public avoided staying in public areas. Such avoidance behaviors could greatly impact daily routines of the community and the local economy. This study examined the prevalence of the avoidance behaviors (i.e. avoiding going out, visiting crowded places and visiting hospitals) and negative psychological responses of the general population in Hong Kong at the initial stage of the H1N1 epidemic.  相似文献   
23.
This study evaluated the use of red and infrared lasers on tissue surrounding the femurs of 60 rats randomly divided into three groups after implantation of bioabsorbable plates. The control group were not subjected to laser irradiation; group A was treated with red laser [indium–gallium–aluminum–phosphide (InGaAlP) laser, wavelength 685 nm, 35 mW, continuous wave (CW), Ø?=?0.06 cm, 2.23 min], and group B was subjected to infrared laser [gallium–aluminum–arsenium (GaAlAs) laser, wavelength 830 nm, 50 mw, CW, Ø?=?0.06 cm, 1.41 min], both at 10 J/cm2. Samples were stained with hematoxylin and eosin (H&;E) and examined microscopically. Results showed that the laser irradiation had had a positive photobiomodulation effect on inflammation, confirmed by a better histologic pattern than that of the control group at 3 days and 7 days. Semiquantitative analysis revealed that groups A and B had a histologic score significantly greater than that of the control group at 3 days. At 21 days, histomorphometric analysis revealed a more intense inflammation in the red laser group than in the other groups. We concluded that low-level laser therapy (LLLT) has positive effects on the photobiomodulation of inflammation in the tissues surrounding the poly-L-lactic/polyglycolic acid (PLLA/PGA) bioabsorbable plate. It stimulated vascularization, fibroblast proliferation, and collagen deposition.  相似文献   
24.
PURPOSE: To measure T(1) and T(2) of the fine structures of the in vivo eye. MATERIALS AND METHODS: Involuntary saccades make it difficult to obtain artifact-free images. Using a method recently reported (Bert et al, Acad Radiol 2006;12:368-378), near artifact-free spin-echo images were obtained. Both an isolated enucleated eye and eight human subjects were studied at 1.5 T. Spin-echo variable TR/TE data was acquired for T(1)/T(2) determination. Average relaxation times were calculated two ways. First, an arithmetic average over different subjects was computed. Second, all data was normalized using the fitted amplitudes of each data set and pooled to obtain a single least squares fit. RESULTS: In vivo T(1)/T(2) (msec) are: arithmetic average T(1), T(2), normalized data T(1), T(2). Anterior chamber: 6233 +/- 979, 468 +/- 149, 5053 +/- 1052, 450 +/- 49. Ciliary body: 1916 +/- 184, 80 +/- 7, 2038 +/- 114, 76 +/- 3. Chorioretina: 1717 +/- 500, 72 +/- 25, 1511 +/- 230, 78 +/- 3. Extraocular muscle: 1581 +/- 646, 41 +/- 7, 1470 +/- 231, 41 +/- 1. Iris: 3334 +/- 989, 163 +/- 63, 3376 +/- 338, 153 +/- 10. Lens cortex: 1712 +/- 466, 93 +/- 36, 1413 +/- 177, 100 +/- 5. Lens nucleus: 1133 +/- 40, 26 +/- 3, 1138 +/- 47, 25 +/- 0.4. Optic nerve: 1906 +/- 301, 68 +/- 16, 1805 +/- 244, 71 +/- 2. Posterior chamber: 7915 +/- 4897, 241 +/- 14, 3323 +/- 2154, 251 +/- 38. Vitreous humor: 5768 +/- 1190, 756 +/- 804, 4855 +/- 1846, 390 +/- 8. CONCLUSION: In vivo T(1) and T(2) for many of the fine structures of the human eye have been measured.  相似文献   
25.

Problem

A multinational company with operations in several African countries was committed to offer antiretroviral treatment to its employees and their dependants.

Approach

The Accelerating Access Initiative (AAI), an initiative of six pharmaceutical companies and five United Nations’ agencies, offered the possibility of obtaining brand antiretroviral drugs (ARVs) at 10% of the commercial price. PharmAccess, a foundation aimed at removing barriers to AIDS treatment in Africa, helped to establish an HIV policy and treatment guidelines, and a workplace programme was rolled out from September 2001.

Local setting

Private sector employers in Africa are keen to take more responsibility in HIV prevention and AIDS care. An important hurdle for African employers remains the price and availability of ARVs.

Relevant changes

The programme encountered various hurdles, among them the need for multiple contracts with multiple companies, complex importation procedures, taxes levied on ARVs, lack of support from pharmaceutical companies in importation and transportation, slow delivery of the drugs, lack of institutional memory in pharmaceutical companies and government policies excluding the company from access to ARVs under the AAI.

Lessons learned

The launch of the AAI enabled this multinational company to offer access to ARVs to its employees and dependants. The private sector should have access to these discounted drugs under the AAI. A network of local AAI offices should be created to assist in logistics of drugs ordering, purchase and clearance. No taxes should be levied on ARVs.  相似文献   
26.
Background: Current oral therapy for hepatitis B virus (HBV) is limited by the presence of resistance leading to resumption of higher levels of HBV replication. Therefore, there is a need for a better definition of the potential role and limitations of lamivudine or similar therapies, used alone. Aims: To examine the viability of lamivudine and similar monotherapies as a treatment strategy in chronic HBV in the face of the worldwide burden of disease. Methods: We have reviewed the role of lamivudine monotherapy in the treatment of chronic HBV in a single tertiary referral liver centre over a 9‐year period. We analysed the outcome in 90 patients where lamivudine has apparently conferred long‐term viral suppression and investigated the development of genotypic resistance in the absence of ostensible phenotypic resistance. Patients were subdivided into hepatitis B e antigen (HBeAg)‐positive and anti‐HBe‐positive groups. Results: Virtually all HBeAg‐positive patients who failed to seroconvert have progressed to combination antiviral therapy. Only 19%(7/36) of HBeAg‐negative patients have continued suppression without detectable genotypic change after 4 years of therapy. Conclusions: These data demonstrate that despite a relatively low level of viraemia in HBeAg‐negative patients, we could detect resistance mutations by direct sequencing in all patients with amplifiable HBV DNA. Our results suggest that for patients with ongoing replication at ‘amplifiable’ levels of HBV DNA, but <105 copies/ml, genotypic selection is readily detectable. Lamivudine monotherapy has not sufficed for the overwhelming majority of patients.  相似文献   
27.
28.

Background

Medication-overuse headache (MOH) is caused by the regular use of medications to treat headache. There has been a lack of research into awareness of MOH. We distributed an electronic survey to undergraduate students and their contacts via social networking sites. Analgesic use, awareness of MOH, perceived change in behaviour following educational intervention about the risks of MOH and preferred terminology for MOH was evaluated.

Findings

485 respondents completed the questionnaire (41% having received healthcare training). 77% were unaware of the possibility of MOH resulting from regular analgesic use for headache. Following education about MOH, 80% stated they would reduce analgesic consumption or seek medical advice. 83% indicated that over the counter analgesia should carry a warning of MOH. The preferred terminology for MOH was painkiller-induced headache.

Conclusions

This study highlights the lack of awareness of MOH. Improved education about MOH and informative packaging of analgesics, highlighting the risks in preferred lay terminology (i.e. painkiller-induced headache), may reduce this iatrogenic morbidity and warrants further evaluation.  相似文献   
29.
30.
Platelet-derived growth factor promotes polymorphonuclear leukocyte activation   总被引:13,自引:0,他引:13  
Tzeng  DY; Deuel  TF; Huang  JS; Senior  RM; Boxer  LA; Baehner  RL 《Blood》1984,64(5):1123-1128
The platelet-derived growth factor (PDGF) has several well defined important biologic activities. Platelet-derived growth factor is the major mitogen in human serum for cells of mesenchymal origins; it is a potent chemoattractant protein for human monocytes, neutrophils, fibroblasts, and smooth muscle cells; and has been implicated in transformation by simian sarcoma virus and perhaps in transformation by other agents as well. In this article, PDGF has been shown to stimulate activation of human peripheral blood neutrophils defined by loss of membrane associated calcium as reflected by loss of chlortetracycline fluorescence, release of superoxide anion and specific granule enzymes, and enhanced neutrophil adherence and aggregation. These responses occurred in a dose-dependent fashion at concentrations of PDGF between 10 ng/mL (0.4 nmol/L) and 40 ng/mL (1.5 nmol/L) and were comparable to effects obtained with optimal concentrations of fMLP and C5a. Degranulation induced by PDGF was selective for secondary (specific) granules and not primary (azurophil) granules. Platelet-derived growth factor thus is ideally suited for a pivotal role in attracting inflammatory cells locally and initiating neutrophil activation at sites of blood vessel injury. Platelet-derived growth factor or a closely related protein also may play an important role in attracting and activating neutrophils in association with inflammatory tumors.  相似文献   
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