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51.
Rheologic predictors of the severity of the painful sickle cell crisis   总被引:4,自引:0,他引:4  
Ballas  SK; Larner  J; Smith  ED; Surrey  S; Schwartz  E; Rappaport  EF 《Blood》1988,72(4):1216-1223
Deformable sickle erythrocytes have been reported by Mohandas and Evans to be more adherent to vascular endothelium than rigid irreversibly sickled cells (ISC). To define the clinical implications of this finding we have determined genetic, hematological, clinical, and rheological characteristics of sickle erythrocytes obtained from 65 patients with sickle cell anemia and fetal hemoglobin (Hb F) levels less than 15%. The alpha-globin gene number had a significant effect on the hematological parameters, the percentage of dense cells, ISC number, and HB A2 levels. The presence or absence of alpha thalassemia, however, had no effect on the frequency and severity of the sickle cell painful crisis (r = 0.06, P greater than .05). RBC deformability, determined by an ektacytometer, showed great heterogeneity among patients with three or four alpha-globin genes. Linear regression analyses of the data showed significant positive correlation of the frequency and severity of the painful crisis with RBC deformability (r = 0.49, P less than .001), and negative correlations with the percentage of dense cells (r = -0.37, P = .002), and the percentage of ISC (r = -0.46, P less than .001). We propose that the more deformable the sickle RBC are, the greater their adherence to vascular endothelium, and the more they cause vaso-occlusive crises, RBC deformability and the percentage of dense cells (or ISC) seem to have a predictive value of the frequency and severity of painful crises in sickle cell anemia.  相似文献   
52.
Background: We conducted a case study of the Zimbabwe National AIDS Trust Fund (‘AIDS Levy’) as an approach to domestic government financing of the response to HIV and AIDS.

Methods: Data came from three sources: a literature review, including a search for grey literature, review of government documents from the Zimbabwe National AIDS Council (NAC), and key informant interviews with representatives of the Zimbabwean government, civil society and international organizations.

Findings: The literature search yielded 139 sources, and 20 key informants were interviewed. Established by legislation in 1999, the AIDS Levy entails a 3% income tax for individuals and 3% tax on profits of employers and trusts (which excluded the mining industry until 2015). It is managed by the parastatal NAC through a decentralized structure of AIDS Action Committees. Revenues increased from inception to 2006 through 2008, a period of economic instability and hyperinflation. Following dollarization in 2009, annual revenues continued to increase, reaching US$38.6 million in 2014. By policy, at least 50% of funds are used for purchase of antiretroviral medications. Other spending includes administration and capital costs, HIV prevention, and monitoring and evaluation. Several financial controls and auditing systems are in place. Key informants perceived the AIDS Levy as a ‘homegrown’ solution that provided country ownership and reduced dependence on donor funding, but called for further increased transparency, accountability, and reduced administrative costs, as well as recommended changes to increase revenue.

Conclusions: The Zimbabwe AIDS Levy has generated substantial resources, recently over US$35 million per year, and signals an important commitment by Zimbabweans, which may have helped attract other donor resources. Many key informants considered the Zimbabwe AIDS Levy to be a best practice for other countries to follow.  相似文献   

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Khan  Sara  Shridharmurthy  Divya  Lapane  Kate L.  Dube  Catherine  Kay  Jonathan  Yi  Esther  Liu  Shao-Hsien 《Clinical rheumatology》2022,41(4):1115-1124
Clinical Rheumatology - Axial spondyloarthritis (axSpA) affects patients’ health-related quality of life (HRQoL). Prior studies have documented gender differences in axSpA across the disease...  相似文献   
55.
INTRODUCTION: Coeliac disease causes histological changes throughout the small bowel, but is often a proximal lesion. We wanted to assess whether terminal ileal histological abnormalities occurred more commonly in patients with coeliac disease and if specific assessment of intraepithelial lymphocytes increases the recognition of undiagnosed coeliac disease. METHODS: Terminal ileal biopsies were prospectively examined over a 3-year period (April 2001-May 2004). Patients were included if they were found to have a synchronous duodenal biopsy that gave a new diagnosis of coeliac disease (n=20). Terminal ileal biopsies taken at colonoscopy during the same period were also examined from four groups of patients: coeliac disease established on a gluten-free diet but with persisting symptoms (n=25), inflammatory bowel disease (n=47), chronic diarrhoea (n=44) and polyp surveillance (n=47). All biopsies were graded according to the Marsh criteria and an intraepithelial lymphocytes count per 100 enterocytes was obtained. RESULTS: There was only one patient from all five groups who had villous atrophy of the terminal ileal. This patient had a new diagnosis of coeliac disease. The mean intraepithelial lymphocytes count in the coeliac disease group was 23.7 intraepithelial lymphocytes/100 enterocytes. This was significantly higher than the control groups: coeliac disease on a gluten-free diet=17.5 (p<0.012), inflammatory bowel disease=12.3 (p<0.0001), diarrhoea=12.6 (p<0.0001) and polyp=13.7 (p<0.0002). Validating terminal ileal villous intraepithelial lymphocytes counts as a test for coeliac disease using an intraepithelial lymphocytes/100 enterocytes of >25 gives a sensitivity of 45% and a specificity of 97.8%. CONCLUSION: Routinely quantifying terminal ileal intraepithelial lymphocytes may be of limited clinical value. However, subjective recognition of raised intraepithelial lymphocytes on a terminal ileal biopsy should alert the clinician to the possibility of coeliac disease.  相似文献   
56.
Objective: To evaluate the impact of amniotic fluid “sludge” (AFS) on the risk of preterm delivery and to describe the effect of antibiotic treatment in that situation.

Methods: Case–control study including singleton pregnancies with or without AFS, between 15–32 weeks of gestation. Factors associated with preterm delivery before 32 weeks, 34 weeks and 37 weeks were evaluated with univariate and multivariate logistic regression. Since all women with AFS in this study were treated with antibiotics, a historical comparison was performed with similar patients with AFS found before 2007 and not treated with antibiotics.

Results: AFS was observed in 90/1220 patients (7.4%). AFS was associated with shorter cervical length, greater body mass index, cervical cerclage and preterm birth before 28 weeks. However, after adjustment, AFS did not remain associated with preterm delivery before 32 or 34 weeks. The historical comparison suggested that azithromycin could significantly reduce the risk of preterm delivery before 34 weeks (odds ratio: 0.2; 95% CI: 0.04–0.92).

Conclusions: AFS, treated with azithromycin, was associated with a higher risk of prematurity, but not independently after adjustment for cervical length and second trimester vaginal bleeding. Further studies need to evaluate the effect of antibiotics in pregnancies with AFS.  相似文献   

57.
To evaluate the significance of micrometastases in relation to survival rate, specimens from 48 colorectal carcinoma patients were analysed after fat clearance. The number and size of the lymph nodes harbouring metastases and the significance of micrometastases for patients' survival were assessed. We found that although the majority of metastatic lymph nodes (71.8%) were 5 mm or less in diameter, their size had no effect on survival. Immunohistochemical staining of lymph nodes revealed that 15 of 25 patients with Dukes' stage B diagnosed by routine staining had micrometastases, 86% of these lymph nodes being less than 5 mm in diameter. The survival rate of this subgroup was found to be considerably poorer than that of Dukes' stage B patients with no micrometastases. None of the three patients with Dukes' stage A carcinoma had micrometastases. Since most of the metastases and micrometastases occur in lymph nodes of 5 mm and less and can be easily missed by routine examination, we suggest that fat clearance and routine immunohistochemical analysis of Dukes' stage B improve the prediction of outcome of colorectal cancer patients. Accepted: 10 February 1998  相似文献   
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59.
Corpus luteum rupture presenting as acute abdomen is an underdiagnosed condition. Though a self-limiting entity, its differentiation from other causes is essential to prevent unnecessary surgical procedures. The radiologist should be aware of the possibility of a ruptured haemorrhagic ovarian cyst in a female of reproductive age group presenting with pelvic pain and a large amount of haemorrhagic ascites. Imaging characteristically reveals a thick-walled cystic structure in the adnexa with internal echoes, focal discontinuity or irregularity of its wall with haemoperitoneum. While sonography is usually indicative of corpus luteum rupture, cross-sectional imaging (CT/MRI) can be used to confirm the diagnosis.  相似文献   
60.

Background:

de Quervain''s tenosynovitis is an inflammation of abductor pollicis longus (APL) and extensor pollicis brevis (EPB) muscle tendon sheaths at the level of radial styloid process. Its conservative management includes nonsteroidal anti-inflammatory drugs, wrist and thumb immobilization, ultrasonic therapy (US Th.) and low level laser therapy (LLLT). Literature is scanty on comparative efficacy of US Th. and LLLT for its management. This prospective study evaluates outcome of US Th. versus LLLT in de Quervain''s disease.

Materials and Methods:

Thirty patients clinically diagnosed de Quervains tenosynovitis were included in the study and randomly assigned to two groups. The average age was 36 years (range: 21-45 years). One group was given LLLT and the other US Th. for a total of 7 exposures on alternate days. The clinical criteria used were Finkelstein''s test, tenderness over radial styloid (Ritchie''s tenderness scale), grip strength, pain (visual analog scale [VAS]) and radiological criteria was ultrasonographic assessment of change in thickness of APL and EPB tendon sheath. They were measured before commencement and at the end of seven sessions of therapy, as per standard procedure.

Results:

Significant improvement was seen within both groups in the following outcome measures assessed: Ritchie''s tenderness scale, grip strength and VAS. Finkelstein''s test was not significantly improved in either groups. Ultrasonographic measurement of tendon sheath diameters, the mediolateral (ML), and anteroposterior (AP) diameters was not found to be significantly different in the US Th. group and the laser therapy group after treatment. On comparing both the groups, no statistically significant difference was found. However, looking at the mean values, the grip strength and VAS showed better improvement in the US Th. group as compared to the laser therapy group.  相似文献   
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