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61.
Digestive Diseases and Sciences - Esophageal diverticula can cause significant symptoms and affect the quality of life. There has been recent interest in the use of peroral endoscopic myotomy in...  相似文献   
62.
Accurate mapping of timber resources in commercial forestry is essential to support planning and management operations of forest growers. Over the last two decades, Light Detection and Ranging (LiDAR) systems have been successfully deployed for the collection of point-cloud data for accurate modelling of forest attributes that are traditionally obtained from plot-based inventory. In recent years, studies conducted in North America and Scandinavia have shown that three-dimensional point clouds derived from digital aerial photogrammetric (AP) data can be used to model forest attributes with a level of accuracy similar to traditional LiDAR-based approaches. A comparative analysis of the performance of the two point-cloud technologies has never been attempted in Australian plantations. In this study, we compared the performance of LiDAR-based and AP-based point clouds for estimating total recoverable volume in a Pinus radiata plantation at Springfield in north-eastern Tasmania, using volume data collected by harvesting machines as a reference. Our results showed that AP point clouds can be used for mapping total recoverable volume in P. radiata plantations with levels of accuracy that are comparable to LiDAR-based estimates. Plot-level relative root mean squared error (RMSE%) values were 23.85% for LiDAR and ranged from 22.07% to 27.10% for the three AP dense point-cloud settings evaluated. At the stand level, RMSE% decreased to 9.86% and 8.91% for LiDAR and AP, respectively. Both LiDAR-based and AP-based modelled volumes showed a close agreement with volumes measured using harvester head data, demonstrating the potential of AP technology for the management and planning of forestry operations in softwood plantations.  相似文献   
63.
Eating disorders are a group of psychiatric conditions characterised by disturbances in eating behaviour along with severe concern regarding bodyweight and shape, which appear to be on the rise in South Asian countries. These disorders are commonly observed in young individuals and are caused by a complex interaction of genetic, biological, psychological and social factors and associated with a wide range of adverse physical, psychological and social consequences. Treatment of these disorders can be quite expensive as it requires specialised care from a multidisciplinary team. Hence, prevention of eating disorders is essential; this should focus on modifiable risk factors such as the media and low self‐esteem, which contribute to body image dissatisfaction in young people and increases their risk of developing an eating disorder. This article provides recommendations for prevention of eating disorders specifically in the South Asian context.  相似文献   
64.
The OptiMAL test detects both Plasmodium falciparum and P. vivax malaria infections. In this study, we evaluated the performance of the OptiMAL test at the Basic Health Units (BHUs) and the District Health Quarter (DHQ) Center in rural villages of Punjab, Pakistan that provide minimal health services. Two sets of blood specimens obtained from 930 suspected malaria patients attending these BHUs were tested at BHUs and the DHQ Center by microscopy and the OptiMAL test. At the BHUs, 231 (25%) of the patients were positive by microscopy and 278 (30%) patients tested positive by the OptiMAL test. At the DHQ Center, microscopic analysis of a second set of specimens from the same patients confirmed the malaria infection in 386 (42%) patients and the OptiMAL test result was positive in 300 (32%) patients. To determine the performance of OptiMAL test at the BHUs and the DHQ Center, all data were compared with microscopy results obtained at the DHQ Center. The OptiMAL test results for P. falciparum at the BHUs were comparable to those of the OptiMAL test at the DHQ Center. However, the sensitivity, positive predictive value (PPV), and negative predictive value (NPV) of the OptiMAL test were considerably lower for P. vivax infections than for P. falciparum infections, irrespective of whether the test was performed at the BHUs or at the DHQ Center (P. falciparum: sensitivity = 78-85%, PPV = 89-97%, NPV = 96-98%; P. vivax: sensitivity = 61-76%, PPV = 88-95%, NPV = 90-93%). The OptiMAL test also detected a number of false-positive and false-negative results at both the BHUs and the DHQ Center. The false-positive results ranged from 1% to 2%; however, the number of false-negative results was much higher (BHUs: P. falciparum = 22%, P. vivax = 39%; DHQ Center: P. falciparum = 15%, P. vivax = 24%). In conclusion, these results, when combined with other advantages of the OptiMAL test, suggest that this test can be used by relatively inexperienced persons to diagnose malaria infection in rural areas where facilities for microscopy are not available.  相似文献   
65.
BACKGROUND & AIMS: Celiac disease and hereditary hemochromatosis are common HLA-defined conditions in northwestern Europe. We sought to determine whether there is a genetic relationship between the 2 diseases and if hemochromatosis susceptibility gene (HFE) mutations are protective against iron deficiency in celiac disease. METHODS: Polymerase chain reaction amplification using sequence-specific primers capable of identifying the 2 HFE gene mutations (H63D and C282Y) and the HLA class I and II alleles was used to type 145 white patients with celiac disease and 187 matched controls. Hemoglobin and fasting serum iron levels in celiac patients were measured at diagnosis. RESULTS: HFE gene mutations, H63D or C282Y, were identified in 70 celiac patients (48.3%) and 61 controls (32.6%) (P = 0.004). The C282Y mutation was associated with HLA-A*03 and B*07 alleles in controls and with A*01, A*03, B*08, and DRB1*0301 alleles in celiac patients; the H63D mutation was associated with HLA-A*25 and DRB1*03 alleles in controls and A*29 and DRB1*03 alleles in celiac patients. At diagnosis, celiac patients with the C282Y mutation had higher mean hemoglobin and fasting serum iron levels compared with the HFE wild type (P = 0.0002 and 0.006, respectively). This was not observed with the H63D mutation. CONCLUSIONS: In celiac disease, HFE gene mutations are common and are in linkage disequilibrium with different HLA alleles compared with controls. A disease-specific haplotype that carries C282Y and DQB1*02 is suggested. We propose that HFE gene mutations provide a survival advantage by ameliorating the iron deficiency seen in celiac patients.  相似文献   
66.
Thyrotoxicosis is associated with a high-turnover osteoporosis, which has been solely attributed to elevated thyroid hormone levels. Mice lacking the thyroid hormone receptors α and β establish a role for thyroid hormones in regulating bone remodeling. We show that TSH, which falls when thyroid hormones rise, directly suppresses bone remodeling, and that TSH receptor null mice have profound bone loss. We suggest that reduced TSH signaling contributes to hyperthyroid osteoporosis and that TSH and its receptor could become valuable drug targets.  相似文献   
67.
This review summarizes the effects of beta2-agonists on asthma severity. There has been a controversy as to whether the regularly scheduled use of beta2-adrenergic agonists increases the risk of adverse outcomes in asthma. A number of epidemiological and clinical studies have found an association between the regularly scheduled use of beta-agonist drugs and increased risk of asthma morbidity and mortality. However, this observation has not been consistent across studies. We discuss here the potential mechanisms to explain the relationship between the use of beta-agonists on a regularly scheduled basis and adverse outcomes of asthma therapy; and we provide a brief review of the effect of genetic diversity at the beta2-adrenergic receptor locus on asthma severity. Overall, the evidence suggests that the beta2-agonists in current use in the United States are generally safe and effective; friends, not foes.  相似文献   
68.
Iqbal F  Michaelson J  Thaler L  Rubin J  Roman J  Nanes MS 《Chest》1999,116(6):1616-1624
BACKGROUND: Men with chronic lung disease (CLD) are at risk for osteoporosis, but the relative contributions of their chronic pulmonary disease, glucocorticoid therapy, and other factors toward loss of bone has not been established. Understanding the relative importance of these factors would assist in selecting patients for bone densitometry screening and in policy decisions regarding Medicare reimbursement. OBJECTIVE: To identify patients with CLD who are most likely to benefit from bone densitometry screening based on clinical and biochemical measures. DESIGN: Cross-sectional medical survey. PATIENTS: Patients with CLD who were treated with either oral, inhaled, or no glucocorticoid therapy. A control group without lung disease was recruited from the same clinic population. MEASUREMENTS: Dual-energy X-ray absorptiometry was obtained for each group, and the association between bone mass and clinical variables, glucocorticoid use, gonadal hormones, and biochemical markers of bone metabolism was determined. RESULTS: Osteoporosis (a T score < -2.5 at the hip or spine) was five times as likely in patients with CLD as in control subjects. Although the prevalence of osteoporosis was higher (ninefold) after chronic glucocorticoid therapy, patients with CLD who had never been treated with glucocorticoids had a substantial (fourfold) risk of osteoporosis. Chronic inhaled glucocorticoid therapy offered no protection from bone loss compared to treatment with oral glucocorticoids. Of the clinical and biochemical measures that were obtained, bone mass was weakly correlated with body mass index (BMI), serum estradiol-17beta, and N-telopeptide, but not with testosterone, alkaline phosphatase, bone-specific alkaline phosphatase, or osteocalcin. CONCLUSION: Patients with CLD should be considered for bone densitometry screening regardless of glucocorticoid use. Those patients with a low BMI and/or decreased serum estradiol-17beta comprise a subgroup with increased risk for osteoporosis.  相似文献   
69.
In September 2012, the Centers for Disease Control and Prevention (CDC) initiated an outbreak investigation of fungal infections linked to injection of contaminated methylprednisolone acetate (MPA). Between 2 October 2012 and 14 February 2013, the CDC laboratory received 799 fungal isolates or human specimens, including cerebrospinal fluid (CSF), synovial fluid, and abscess tissue, from 469 case patients in 19 states. A novel broad-range PCR assay and DNA sequencing were used to evaluate these specimens. Although Aspergillus fumigatus was recovered from the index case, Exserohilum rostratum was the primary pathogen in this outbreak and was also confirmed from unopened MPA vials. Exserohilum rostratum was detected or confirmed in 191 specimens or isolates from 150 case patients, primarily from Michigan (n = 67 patients), Tennessee (n = 26), Virginia (n = 20), and Indiana (n = 16). Positive specimens from Michigan were primarily abscess tissues, while positive specimens from Tennessee, Virginia, and Indiana were primarily CSF. E. rostratum antifungal susceptibility MIC50 and MIC90 values were determined for voriconazole (1 and 2 μg/ml, respectively), itraconazole (0.5 and 1 μg/ml), posaconazole (0.5 and 1 μg/ml), isavuconazole (4 and 4 μg/ml), and amphotericin B (0.25 and 0.5 μg/ml). Thirteen other mold species were identified among case patients, and four other fungal genera were isolated from the implicated MPA vials. The clinical significance of these other fungal species remains under investigation. The laboratory response provided significant support to case confirmation, enabled linkage between clinical isolates and injected vials of MPA, and described significant features of the fungal agents involved in this large multistate outbreak.  相似文献   
70.
Journal of NeuroVirology - South Africa has the world’s largest antiretroviral programme which has resulted in an increase in life expectancy in persons living with HIV. Parkinson’s...  相似文献   
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