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61.
62.
We evaluated free-breathing, prospective navigator-gated, three-dimensional (3D) magnetic resonance coronary angiography (MRCA) with hybrid ordered phase-encoding (HOPE), in the detection of proximal coronary artery stenosis. The coronary arteries were imaged in 46 patients undergoing cardiac catheterization. The mean scan time was 48 minutes. The mean arterial length (mm) visualized was left main stem (LMS) 11.7 (SD 4.5), left anterior descending (LAD) 30.1 (SD 11.1), circumflex (LCx) 15.5 (SD 8.6), and right (RCA) 56.2 (SD 20.8). Twenty-three patients had coronary artery disease with 47 significant stenoses on cardiac catheterization. All LMS were normal on both catheterization and MRCA. MRCA sensitivity was highest for the LAD (89% CI 65%-99%) and RCA (76% CI 50%-93%), but lower for the LCx (50% CI 21%-79%). Specificity ranged from 72%-100%. Improvements in image quality, length of vessel seen, and specific imaging of the LCx are required for MRCA to become an alternative to cardiac catheterization.  相似文献   
63.
In terms of mortality, morbidity and disability, burns are emerging as a major child health problem in Bangladesh. This trend is similar to many other developing countries. To develop effective burn prevention programmes, information on its magnitude and determinants is necessary. The purpose of this study was to document the magnitude and determinant of childhood burns in Bangladesh, based on a population-based survey which was conducted between January and December 2003. Nationally representative data was collected from 171,366 rural and urban households, comprising of a total population of 819,429. To facilitate data collection, face-to-face interviews were conducted. The rate of non-fatal burn among children under 18 years of age was calculated as 288.1 per 100,000 children-year. The highest incidence (782.1/100,000 children-year) was found among the 1-4 years age group. About 46% of non-fatal burn injuries occurred between 9 a.m. and 3 p.m. The incidence of childhood burn was found to be more than four times higher in rural children than urban children. Ninety percent (90%) of the childhood burns occurred at homes and the kitchen was the most common place. The rate of disability due to burn was 5.7 per 100,000 children per year. The rate of fatal burn was 0.6 per 100,000 per year among all children. The study findings confirmed that childhood burn was a major childhood illness in Bangladesh. An urgent and appropriate prevention programme is required to prevent these unwanted morbidities, disabilities and deaths due to burn.  相似文献   
64.
Tuberculous spondylitis: analysis of 69 cases from Saudi Arabia.   总被引:3,自引:0,他引:3  
DESIGN: Retrospective chart and radiographic review of all cases admitted to the authors' hospital and diagnosed to have tuberculous spondylitis. OBJECTIVE: To identify the frequency, presenting features, utility of diagnostic tests, and treatment outcome of spinal tuberculosis in a tertiary care center. METHODS: All cases of spinal tuberculosis treated in the authors' hospital over 14 years were reviewed. Only those with histologic or microbiologic confirmation or those who responded to antituberculous spondylitis therapy were included. Outcome was assessed according to predefined criteria. RESULTS: Between 1985 and 1998, 69 cases of tuberculous spondylitis were found, i.e., 5% of all tuberculous spondylitis cases diagnosed. The mean age was 52.8 years (range, 15-80 years), and 37 (53.6%) were male. Only five patients had a history of tuberculosis. The most frequent symptoms were backache (84%) and fever (32%), and the most frequent sign was spinal tenderness (45%). Nineteen (28%) patients had paraparesis and 12 (17%) had kyphosis. Except for elevated sedimentation rate (94.5%), the laboratory workup was not helpful. Both computed tomography and magnetic resonance imaging were found to be helpful in diagnosis, often with complementary information. Thirty-eight patients (55%) had thoracic spine involvement and 55 patients (80%) had paraspinal abscesses. Tissue aspirates had a yield of 70%, 35%, and 57% for granulomas, acid-fast bacilli smear, and culture, respectively. Medical therapy alone was given in 37 cases (54%), whereas 32 patients (46%) required additional surgical intervention, mainly those with spinal cord compression, spinal deformity, or risk of spinal instability. There was definite improvement in 63 cases (91%). The best outcome was in those patients presenting early before the occurrence of spinal deformity or neurologic symptoms. CONCLUSION: Tuberculous spondylitis is prevalent in the authors' hospital. Both computed tomography and magnetic resonance imaging are extremely helpful for diagnosis, and tissue aspirate is a good confirmatory method. A good outcome is expected if the diagnosis is made in early stages before the appearance of spinal deformity and neurologic symptoms. Surgical intervention can be avoided in these cases regardless of the presence or absence of paraspinal abscesses.  相似文献   
65.
Published literature on fracture in dialysis patients seldom addressed the effect of co‐morbidity and malnutrition. In this study, we reported the incidence and risk factors for fracture in peritoneal dialysis patients. Peritoneal dialysis patients who had fractures between 2006 and 2011 were recruited. Demographic data, details of fracture, Charlson Co‐morbidity Index (CCI) and biochemical parameters were also collected. Non‐fracture controls, matched for age, gender and duration of dialysis, were also recruited at ratio 1:1 for fracture risk analysis. The incidence of fracture was 1 in 37 patient‐years. The commonest site of fracture was neck of femur (n = 16, 55.2%). Twenty‐four patients (82.8%) developed fracture after slip and fall injury. Eight out of 17 self‐ambulatory patients (47.1%) became non‐ambulatory after fracture. Infection was the commonest complication during hospitalization. Univariant analysis demonstrated high CCI (P = 0.001), hypoalbuminaemia (P < 0.001), loss of self autonomy (P = 0.006) and non‐ambulatory state (P = 0.011) significantly associated with increased fracture risk. However, only CCI (odds ratio (OR) 1.373, P = 0.028) and albumin (OR 0.893, P = 0.025) increased fracture risk significantly on multivariant analysis. Bone profile and parathyroid hormone were not significant risk factors. To conclude, fracture associated with adverse outcome in peritoneal dialysis patients. High CCI score and hypoalbuminaemia significantly increase risk of fracture.  相似文献   
66.
67.
Solid organ transplant (SOT) recipients may be at higher risk for poor outcomes with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Convalescent plasma is an investigational therapy that may benefit immunosuppressed patients by providing passive immunity. Convalescent plasma was administered to hospitalized patients with coronavirus disease-2019 (COVID-19) at an academic transplant center in New York City. Eligible patients were hospitalized and required to have positive nasopharyngeal polymerase chain reaction (PCR) diagnosis of SARS-CoV-2 infection, be at least 18 years old, and have either dyspnea, blood oxygen saturation ≤ 93% on ambient air, respiratory frequency ≥ 30 breaths/min, partial pressure of arterial oxygen to fraction of inspired oxygen ratio < 300, or lung infiltrates > 50%. Thirteen SOT recipients received convalescent plasma from April 9, 2020, to May 17, 2020. The median time from symptom onset to plasma infusion was 8 days. Eight of 13 patients (62%) had de-escalating oxygenation support by day 7 post-convalescent plasma. Nine (69%) patients were discharged, 1 (7%) patients remain hospitalized, and 3 (23%) patients died. This series supports the need for additional studies on convalescent plasma use in SOT recipients with COVID-19 to better determine efficacy and identify patients who are likely to benefit.  相似文献   
68.
To define an optimal regimen for mobilizing and collecting peripheral blood progenitor cells (PBPC) for use in allogeneic transplantation, we evaluated the kinetics of mobilization by filgrastim (recombinant met- human granulocyte colony-stimulating factor [r-metHuG-CSF]) in normal volunteers. Filgrastim was injected subcutaneously for up to 10 days at a dose of 3 (n = 10), 5 (n = 5), or 10 micrograms/kg/d (n = 15). A subset of volunteers from each dose cohort underwent a 7L leukapheresis on study day 6 (after 5 days of filgrastim). Granulocyte-macrophage colony-forming cell (GM-CFC) numbers in the blood were maximal after 5 days of filgrastim; a broader peak was evident for CD34+ cells between days 4 and 6. The 95% confidence intervals (CI) for mean number of PBPC per milliliter of blood in the three dose cohorts overlapped on each study day. However, on the peak day, CD34+ cells were significantly higher in the 10 micrograms/kg/d cohort than in a pool of the 3 and 5 micrograms/kg/d cohorts. Mobilization was not significantly influenced by volunteer age or sex. Leukapheresis products obtained at the 10 micrograms/kg/d dose level contained a median GM-CFC number of 93 x 10(4)/kg (range, 50 x 10(4)/kg to 172 x 10(4)/kg). Collections from volunteers receiving lower doses of filgrastim contained a median GM- CFC number of 36 x 10(4)/kg (range, 5 x 10(4)/kg to 204 x 10(4)/kg). The measurement of CD34+ cells per milliliter of blood on the day of leukapheresis predicted the total yield of PBPC in the leukapheresis product (r = .87, P < .0001). Assuming a minimum GM-CFC requirement of 50 x 10(4)/kg (based on our experience with autologous PBPC transplantation), all seven leukapheresis products obtained at the 10 micrograms/kg/d dose level were potentially sufficient for allogeneic transplantation purposes. We conclude that in normal donors, filgrastim 10 micrograms/kg/d for 5 days with a single leukapheresis on the following day is a highly effective regimen for PBPC mobilization and collection. Further studies are required to determine whether PBPC collected with this regimen reliably produce rapid and sustained engraftment in allogeneic recipients.  相似文献   
69.
PURPOSE: The incidence and risk factors for progression of retinopathy during pregnancy in women with type 1 diabetes mellitus were retrospectively evaluated. METHODS: Fifty-four insulin-dependent diabetic patients at a teaching hospital in Saudi Arabia were followed throughout the pregnancy/puerperium with serial ophthalmic examination. Dilated fundus examination was performed in each trimester and puerperium. RESULTS: Progression of diabetic retinopathy in the study occurred in 13/54 (24%) patients--2/22 (9.1%) patients had no diabetic retinopathy initially, 4/20 (20%) had non-proliferative diabetic retinopathy (NPDR) and 7/12 (58.3%) had proliferative diabetic retinopathy (PDR). Of the eight patients with PDR who had no laser treatment before pregnancy, six (75%) showed progression but only one of the four patients who had PDR and laser treatment prior to pregnancy experienced progression of retinopathy. Eight patients in total received panretinal photocoagulation to arrest the progression of retinal disease during pregnancy and only one of them had laser treatment prior to pregnancy. CONCLUSION: Laser photocoagulation for severe NPDR or early PDR prior to pregnancy may protect against rapid progression of PDR. Visual impairment resulting from progression of PDR can be prevented by aggressive laser treatment during pregnancy. Duration of diabetes>15 years, poor glycaemic control and hypertension are high-risk factors in the progression of diabetic retinopathy in pregnancy.  相似文献   
70.
Ivy  SP; Olshefski  RS; Taylor  BJ; Patel  KM; Reaman  GH 《Blood》1996,88(1):309-318
Clinical drug resistance may be attributed to the simultaneous selection and expression of genes modulating the uptake and metabolism of chemotherapeutic agents. P-glycoprotein (P-gp) functions as a membrane-associated drug efflux pump whose increased expression results in resistance to anthracyclines, epipodophyllotoxins, vinca alkaloids, and some alkylating agents. This type of resistance occurs as both de novo and acquired resistance to therapy for leukemia. We have studied P- gp expression and function in childhood acute leukemias by developing a series of doxorubicin- and vincristine-selected CEM, T-cell lymphoblastoid cell lines that recapitulate the low levels of expression and resistance seen clinically. These cell lines have been used to develop flow cytometric assays for the semiquantitative measurements of P-gp expression with the MRK16 monoclonal antibody and P-gp function using the enhanced retention of rhodamine 123 in the presence of verapamil, a resistance modulator. Kolmogorov-Smirnov statistics, represented by the D measurement, are used to determine the difference in level of P-gp expression by comparing MRK16 staining to an IgG2a isotype control. When D is > 0.09, there is an excellent correlation (R = 0.82) between P-gp expression and function. The evaluation of 107 bone marrow specimens from 84 children with lymphoblastic or myelogenous leukemia showed a statistically significant (P = .004) increase in P-gp function at relapse. P-gp expression at relapse, however, approached but did not reach a significant level (P = .097). Using this methodology, we can identify patients with levels of P-gp expression and function that we can define clinically, as well as children with discordant multidrug resistance phenotypes. This study supports the role of P-gp-mediated drug resistance in childhood leukemia and confirms that P-gp expression and function are measurable in their leukemic blasts. These assays provide the means for the in vitro testing of resistance modulators and the monitoring of in vivo response to treatment with these agents.  相似文献   
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