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1.
This investigation describes the epidemiology of Reye's syndrome (RS) during 1991-1994 and compares two different sources of information in the United States. Estimates of the incidence of RS from the Centers for Disease Control and Prevention (CDC) are compared with hospital inpatient data from approximately one third of the hospitals from HCIA, Inc. During 1991-1994, 48 RS cases were reported to the CDC and 93 RS hospitalizations based on HCIA data. When the HCIA data are extrapolated to the US population, there were an estimated 284 hospitalizations. Cases reported from both data sources were similar in distribution by onset, age, and sex. CDC data probably underestimate the incidence of RS due to incomplete reporting and HCIA data may overestimate it because not all cases were known to meet the CDC case definition. The true annual incidence of RS during the study years was probably between 0.2 and 1.1 cases per million population <18 years of age.  相似文献   
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Mycobacterium tuberculosis (Mtb) 38‐kDa antigen is an immunogenic lipoprotein that induces strong T‐cell responses in experimental animals. However, there is limited information on the role of this antigen in human population. In this article, we present the dynamics of pro‐inflammatory (IFN‐γ and TNF‐α) and anti‐inflammatory cytokine (IL‐10) against the 38 kDa in cohorts of pulmonary TB (PTB) patients, household contacts (HHCs), and community controls (CCs) in a high endemic setting. Whole blood assay was used to determine the levels of cytokines in 149 patients, 149 HHCs, and 68 CCs at baseline, 6 months, and 12 months. At baseline, the level of IFN‐γ was significantly (p < 0.0001) higher in CCs and HHCs than in untreated patients. CCs had significantly (p < 0.05) higher level of IFN‐γ than HHCs. There was no significant difference between treated and untreated patients, and there was no significant change in HHCs over 12 months. At baseline, the levels of IL‐10 and TNF‐α were significantly (p < 0.0001) higher in patients than in HHCs and CCs. No significant change was observed between treated patients and untreated patients and HHCs over time. The study shows that IFN‐γ against the 38 kDa discriminates clinical TB from infection and infection from exposure, suggesting its potential for immune protection and diagnosis.  相似文献   
3.
Variant Creutzfeldt-Jakob disease (vCJD) has been reported in 12 countries. We hypothesized that a common strain of agent is responsible for all vCJD cases, regardless of geographic origin. To test this hypothesis, we inoculated strain-typing panels of wild-type mice with brain material from human vCJD case-patients from France, the Netherlands, Italy, and the United States. Mice were assessed for clinical disease, neuropathologic changes, and glycoform profile; results were compared with those for 2 reference vCJD cases from the United Kingdom. Transmission to mice occurred from each sample tested, and data were similar between non-UK and UK cases, with the exception of the ranking of mean clinical incubation times of mouse lines. These findings support the hypothesis that a single strain of infectious agent is responsible for all vCJD infections. However, differences in incubation times require further subpassage in mice to establish any true differences in strain properties between cases.  相似文献   
4.
Variant Creutzfeldt-Jakob disease (vCJD) is a rare, fatal prion disease resulting from transmission to humans of the infectious agent of bovine spongiform encephalopathy. We describe the clinical presentation of a recent case of vCJD in the United States and provide an update on diagnostic testing. The location of this patient’s exposure is less clear than those in the 3 previously reported US cases, but strong evidence indicates that exposure to contaminated beef occurred outside the United States more than a decade before illness onset. This case exemplifies the persistent risk for vCJD acquired in unsuspected geographic locations and highlights the need for continued global surveillance and awareness to prevent further dissemination of vCJD.  相似文献   
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BackgroundRadiation therapy has proven efficacy for cancer treatment but is not without short- and long-term side effects, including radiation-induced lymphedema. There has been limited evidence on the secondary effects of prior radiation therapy on shoulder surgery. The purpose of this study is to evaluate the short-term outcomes of shoulder arthroplasty and rotator cuff repair (RCR) in patients who have undergone ipsilateral radiation therapy and/or have preoperative upper extremity lymphedema.MethodsDuke Enterprise Data Unified Content Explorer was used to query for patients who underwent RCR at our institution. Patients with radiation therapy for breast or lung cancer prior to ipsilateral RCR or shoulder arthroplasty were included. Patients with less than 2 years of follow-up were excluded. Data variables included primary tumor type, dates of cancer diagnoses, radiation treatment, axillary lymph node dissection (aLND), presence of lymphedema, index shoulder operations, most recent follow-up, and surgical and medical complications within the 90-day postoperative period. Additional oncologic variables included total Gray (Gy) delivered.ResultsTwenty-one patients underwent radiation therapy and subsequent shoulder arthroplasty or RCR (13 RCR, 3 total shoulder arthroplasty, 5 reverse shoulder arthroplasty). There were 20 females and 1 male with an average age of 65.6 years (47-82) and average clinical follow-up of 4.4 years (2.0-7.4). Oncologic diagnoses included lung (4.8%) and breast (95.2%) cancer. Average radiation dose delivered was 53.3 Gy (38.5-64) in the cohort. The average time from last external beam radiation therapy to shoulder surgery was 4.3 years (0.3-18.0). One of 13 (7.7%) 90-day postoperative complications was reported in the RCR cohort: a superficial vein thrombosis. One of 8 (12.5%) 90-day complications was reported in the arthroplasty cohort: a clinically suspected but radiographically absent acromial stress fracture in a reverse shoulder arthroplasty that did not require operative intervention. Overall, there were no revisions, reoperations, or shoulder-related unplanned inpatient 90-day readmissions. Among 10 patients with prior aLND, 3 (30%) (2 RCR, 1 arthroplasty) experienced new or worsening upper extremity lymphedema within the immediate postoperative period.ConclusionA minority of patients having undergone prior radiation therapy and aLND who subsequently underwent ipsilateral shoulder surgery experienced worsening subjective upper extremity lymphedema. Although 10% of these radiation therapy patients experienced minor complications within 90 days of their shoulder surgery, none were severe enough to merit inpatient admission or revision surgery.  相似文献   
8.
Cracks in typical mortar constructions enhance water permeability and degrade ions into the structure, resulting in decreased mortar durability and strength. In this study, mortar samples are created that self-healed their cracks by precipitating calcium carbonate into them. Bacillus subtilus bacterium (10−7, 10−9 cells/mL), calcium lactate, fine aggregate, OPC-cement, water, and bagasse ash were used to make self-healing mortar samples. Calcium lactates were prepared from discarded eggshells and lactic acid to reduce the cost of self-healing mortars, and 5% control burnt bagasse ash was also employed as an OPC-cement alternative. In the presence of moisture, the bacterial spores in mortars become active and begin to feed the nutrient (calcium lactate). The calcium carbonate precipitates and plugs the fracture. Our experimental results demonstrated that cracks in self-healing mortars containing bagasse ash were largely healed after 3 days of curing, but this did not occur in conventional mortar samples. Cracks up to 0.6 mm in self-healing mortars were filled with calcite using 10−7 and 10−9 cell/mL bacteria concentrations. Images from an optical microscope, X-ray Diffraction (XRD), and a scanning electron microscope (SEM) were used to confirm the production of calcite in fractures. Furthermore, throughout the pre- and post-crack-development stages, self-healing mortars have higher compressive strength than conventional mortars. The precipitated calcium carbonates were primed to compact the samples by filling the void spaces in hardened mortar samples. When fissures developed in hardened mortars, bacteria became active in the presence of moisture, causing calcite to precipitate and fill the cracks. The compressive strength and flexural strength of self-healing mortar samples are higher than conventional mortars before cracks develop in the samples. After the healing process of the broken mortar parts (due to cracking), self-healing mortars containing 5% bagasse ash withstand a certain load and have greater flexural strength (100 kPa) than conventional mortars (zero kPa) at 28 days of cure. Self-healing mortars absorb less water than typical mortar samples. Mortar samples containing 10−7 bacteria cells/mL exhibit greater compressive strength, flexural strength, and self-healing ability. XRD and SEM were used to analyze mortar samples with healed fractures. XRD, FTIR, and SEM images were also used to validate the produced calcium lactate. Furthermore, the durability of mortars was evaluated using DTA-TGA analysis and water absorption tests.  相似文献   
9.
Difficulty in reaching low-income women for screening mammography   总被引:2,自引:0,他引:2  
Low-income women have a high mortality from breast cancer. Yet, they participate in breast cancer early detection screening programs less than women in the general population. An intervention study to improve screening mammography rates of low-income women participating in Tennessee's TennCare program (state Medicaid and Medicare program) revealed significant barriers to reaching these women. Intervention methods included mail, telephone calls, and home visits. Results indicate that only 38 percent of the women could be contacted for a baseline survey. Reasons for noncontact included absence from home (39 percent), having moved (22 percent), refusal to participate (17 percent), having no physical domicile (15 percent), language barriers (4 percent), and miscellaneous other factors (4 percent). Women with telephones tended to have a relatively higher economic status and were more successfully reached than women without telephones. These findings provide useful insights for future program planning and research design.  相似文献   
10.
Halichondramine (1), a new tetracyclic alkylbipiperidine alkaloid, has been isolated from the marine sponge Halichondria sp., collected in the Dahlak archipelago (the Red Sea), Eritrea. The structure of halichondramine was elucidated by interpretation of MS, COSY, HMQC, HMBC, TOCSY, and HSQC-TOCSY data.  相似文献   
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