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101.
Global budget payment is one of the most effective strategies for cost containment, but its impacts on provider behavior have not been explored in detail. This study examines the theoretical and empirical role of global budget payment on provider behavior. The study proposes that global budget payment with price adjustment is a form of common‐pool resources. A two‐product game theoretic model is derived, and simulations demonstrate that hospitals are expected to expand service volumes, with an emphasis on products with higher price–marginal cost ratios. Next, the study examines the early effects of Taiwan's global budget payment system using a difference‐in‐difference strategy and finds that Taiwanese hospitals exhibited such behavior, where the pursuit of individual interests led to an increase in treatment intensities. Furthermore, hospitals significantly increased inpatient service volume for regional hospitals and medical centers. In contrast, local hospitals, particularly for those without teaching status designation, faced a negative impact on service volume, as larger hospitals were better positioned to induce demand and pulled volume away from their smaller counterparts through more profitable services and products such as radiology and pharmaceuticals. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
102.
Hyun-Mi Kang Eun-Kyoung Lee Byung-Min Song Jipseol Jeong Jun-Gu Choi Joojin Jeong Oun-Kyong Moon Hachung Yoon Youngmi Cho Young-Myong Kang Hee-Soo Lee Youn-Jeong Lee 《Emerging infectious diseases》2015,21(2):298-304
An outbreak of highly pathogenic avian influenza, caused by a novel reassortant influenza A (H5N8) virus, occurred among poultry and wild birds in South Korea in 2014. The aim of this study was to evaluate the pathogenesis in and mode of transmission of this virus among domestic and wild ducks. Three of the viruses had similar pathogenicity among infected domestic ducks: the H5N8 viruses were moderately pathogenic (0%–20% mortality rate); in wild mallard ducks, the H5N8 and H5N1 viruses did not cause severe illness or death; viral replication and shedding were greater in H5N8-infected mallards than in H5N1-infected mallards. Identification of H5N8 viruses in birds exposed to infected domestic ducks and mallards indicated that the viruses could spread by contact. We propose active surveillance to support prevention of the spread of this virus among wild birds and poultry, especially domestic ducks. 相似文献
103.
《International journal of hygiene and environmental health》2015,218(4):386-391
BackgroundSeveral members of a swimming club complained of respiratory symptoms associated with attending a municipal indoor swimming pool. Trichloramine, a volatile chlorination by-product and a potent respiratory irritant, was the most probable culprit, but the exact cause for its presence in excessive concentrations remained elusive.MethodsTwenty-two competitive swimmers and six coaches were evaluated during the outbreak and nine swimmers and four coaches were re-evaluated one year later. Symptoms were recorded by non-standardized history taking; pulmonary function testing included spirometry, measurement of fraction of exhaled nitric oxide (FENO) and histamine provocation. Concentrations of trichloramine in air were measured repeatedly by the method of Héry.ResultsThe most commonly reported symptoms consisted of cough (n = 16), dyspnoea (n = 13), tearing eyes (n = 10) and blocked or runny nose (n = 6). Mean FEV1% predicted was 109.1%. Mean FENO level was 19.7 ppb (higher than 25 ppb in 3 subjects). Airway hyperreactivity to histamine (PC20 ≤ 8 mg/ml) was detected in 22/26 subjects. Measured trichloramine concentrations in air exceeded the maximal concentration (WHO) of 0.5 mg/m3 four times between May and October 2011 and four times between January and March 2012. Polyamine compounds, present in glue used for repairing pipework, were identified as a probable external source of nitrogen resulting in increasing trichloramine concentrations. After the removal of the presumed cause of the excessive trichloramine concentrations, most subjects improved clinically, but several subjects remained symptomatic and had bronchial hyperreactivity.DiscussionA high prevalence of airway hyperreactivity, accompanied by symptoms of upper and lower airways, was detected in swimmers who had been repeatedly exposed to high trichloramine concentrations. A glue containing polyamines, used to repair a pipework, was suspected to be the source of this excessive production of trichloramine. 相似文献
104.
为评估超声内镜检查术(endoscopic ultrasonography,EUS)对胆总管小结石的诊断价值,纳入2018年1月—2021年7月在东南大学附属中大医院住院并诊断为可疑胆总管结石的患者60例。所有患者于同一次住院期间行EUS及磁共振胰胆管成像(magnetic resonance cholangiopancreatography,MRCP)。以经内镜逆行胰胆管造影、开腹探查或腹腔镜胆总管探查结果为金标准,比较EUS及MRCP对胆总管结石的诊断结果,计算2种检查方法的灵敏度、特异度、阳性预测值、阴性预测值。结果显示,60例患者中46例确诊胆总管结石,EUS诊断准确43例,MRCP诊断准确35例;14例患者证实胆总管结石阴性,EUS诊断准确12例,MRCP诊断准确13例。EUS诊断灵敏度明显高于MRCP[93.48%(43/46)比76.09%(35/46),χ2=4.128,P=0.042]。结石直径≤1.0 cm者45例,其中EUS确诊42例,MRCP确诊34例(诊断准确率93.33%比75.56%,χ2=4.145,P=0.042);直径≤0.8 cm者39例,其中EUS确诊36例,MRCP确诊28例(诊断准确率92.31%比71.79%,χ2=4.266,P=0.039);直径≤0.5 cm者26例,其中EUS确诊24例,MRCP确诊16例(诊断准确率92.31%比61.54%,χ2=5.038,P=0.021)。在胆总管结石的诊断方面,EUS有明显的诊断优势,且诊断准确性不受结石大小的影响,因此对于临床高度怀疑胆总管结石但MRCP结果阴性的患者,需进一步行EUS。 相似文献
105.
Luo B Tang L Wang Z Zhang J Ling Y Feng W Sun JZ Stockard CR Frost AR Chen YF Grizzle WE Fallon MB 《Gastroenterology》2005,129(2):682-695
BACKGROUND & AIMS: Hepatic production and release of endothelin 1 plays a central role in experimental hepatopulmonary syndrome after common bile duct ligation by stimulating pulmonary endothelial nitric oxide production. In thioacetamide-induced nonbiliary cirrhosis, hepatic endothelin 1 production and release do not occur, and hepatopulmonary syndrome does not develop. However, the source and regulation of hepatic endothelin 1 after common bile duct ligation are not fully characterized. We evaluated the sources of hepatic endothelin 1 production after common bile duct ligation in relation to thioacetamide cirrhosis and assessed whether transforming growth factor beta1 regulates endothelin 1 production. METHODS: Hepatopulmonary syndrome and hepatic and plasma endothelin 1 levels were evaluated after common bile duct ligation or thioacetamide administration. Cellular sources of endothelin 1 were assessed by immunohistochemistry and laser capture microdissection of cholangiocytes. Transforming growth factor beta1 expression and signaling were assessed by using immunohistochemistry and Western blotting and by evaluating normal rat cholangiocytes. RESULTS: Hepatic and plasma endothelin 1 levels increased and hepatopulmonary syndrome developed only after common bile duct ligation. Hepatic endothelin 1 and transforming growth factor beta1 levels increased over a similar time frame, and cholangiocytes were a major source of each peptide. Transforming growth factor beta1 signaling in cholangiocytes in vivo was evident by increased phosphorylation and nuclear localization of Smad2, and hepatic endothelin 1 levels correlated directly with liver transforming growth factor beta1 and phosphorylated Smad2 levels. Transforming growth factor beta1 also stimulated endothelin 1 promoter activity, expression, and production in normal rat cholangiocytes. CONCLUSIONS: Cholangiocytes are a major source of hepatic endothelin 1 production during the development of hepatopulmonary syndrome after common bile duct ligation, but not in thioacetamide-induced cirrhosis. Transforming growth factor beta1 stimulates cholangiocyte endothelin 1 expression and production. Cholangiocyte-derived endothelin 1 may be an important endocrine mediator of experimental hepatopulmonary syndrome. 相似文献
106.
Scott T. Chiesa Marietta Charakida Georgios Georgiopoulos Frida Dangardt Kaitlin H. Wade Alicja Rapala Devina J. Bhowruth Helen C. Nguyen Vivek Muthurangu Rukshana Shroff George Davey Smith Debbie A. Lawlor Naveed Sattar Nicholas J. Timpson Alun D. Hughes John E. Deanfield 《JACC: Cardiovascular Imaging》2021,14(2):468-478
ObjectivesThis study characterized the determinants of carotid intima-media thickness (cIMT) in a large (n > 4,000) longitudinal cohort of healthy young people age 9 to 21 years.BackgroundGreater cIMT is commonly used in the young as a marker of subclinical atherosclerosis, but its evolution at this age is still poorly understood.MethodsAssociations between cardiovascular risk factors and cIMT were investigated in both longitudinal (ages 9 to 17 years) and cross-sectional (ages 17 and 21 years) analyses, with the latter also related to other measures of carotid structure and stress. Additional use of ultra-high frequency ultrasound in the radial artery at age 21 years allowed investigation of the distinct layers (i.e., intima or media) that may underlie observed differences.ResultsFat-free mass (FFM) and systolic blood pressure were the only modifiable risk factors positively associated with cIMT (e.g., mean difference in cIMT per 1-SD increase in FFM at age 17: 0.007 mm: 95% confidence interval [CI]: 0.004 to 0.010; p < 0.001), whereas fat mass was negatively associated with cIMT (difference: ?0.0032; 95% CI: 0.004 to ?0.001; p = 0.001). Similar results were obtained when investigating cumulative exposure to these factors throughout adolescence. An increase in cIMT maintained circumferential wall stress in the face of increased mean arterial pressure when increases in body mass were attributable to increased FFM, but not fat mass. Risk factor?associated differences in the radial artery occurred in the media alone, and there was little evidence of a relationship between intimal thickness and any risk factor.ConclusionsSubtle changes in cIMT in the young may predominantly involve the media and represent physiological adaptations as opposed to subclinical atherosclerosis. Other vascular measures may be more appropriate for the identification of arterial disease before adulthood. 相似文献
107.
Vidya LIMAYE Tim LU Eugene ANG Amirtharajan KRISHNAN Pravin HISSARIA David GILLIS 《International journal of rheumatic diseases》2007,10(3):248-252
Although common variable immunodeficiency (CVID) is sometimes associated with sarcoidosis/granulomatous disease, there have only been isolated reports of selective immunoglobulin A (IgA) deficiency and granulomatous disease. We present a patient with IgA deficiency who developed Heerfordt syndrome, a variant of neurosarcoidosis. This specific entity has not been previously reported to occur in IgA deficiency. Our case expands the reported associations of IgA deficiency and provides another example to the paucity of reported cases of sarcoidosis occurring in patients with IgA deficiency. As CVID and IgA deficiency have common underlying genetic factors, such an association is biologically plausible. 相似文献
108.
109.
B‐1 cells are innate‐like lymphocytes characterized by spontaneous production of ‘natural’ polyspecific antibodies, often of self‐specificity, and thought to be responsible for tissue homeostasis, mucosal protection, maintaining resting serum immunoglobulin (Ig)M levels and for early immunoglobulin production following infection. Although defined most clearly in mice, a human B‐1 cell counterpart, defined by the phenotype CD19 or 20+CD27+CD43+CD69 or 70–, has been proposed recently, facilitating a study of their role in human humoral immunodeficiencies, such as common variable immunodeficiency (CVID). This study examined circulating B‐1 cells in 27 CVID patients in comparison to age‐matched controls (n = 28). Phenotypic putative B‐1 cell proportions varied widely, but there was an overall 60–70% decrease in CVID (0·039 ± 0·033% of lymphocytes, mean ± standard deviation) compared with controls (0·110 ± 0·159% of lymphocytes, P = 0·0012). This decrease was, however, explained largely by concomitant loss of total CD27+ memory B cells characteristic of CVID, although those with higher memory B cell proportions appeared to show a true decrease. No age‐related effects were apparent in B‐1 cell proportions. However, among CVID patients, there was a strong positive correlation between the B‐1 cell proportion and serum IgM levels, a relationship that was not evident for IgA, nor was there a relationship between memory B cell proportions and serum IgM. Patients with CVID have fewer circulating putative phenotypic B‐1 cells, which largely reflected the overall decrease in memory B cells. However, B‐1 cell proportions correlated with resting serum IgM levels, suggesting a possible role in IgM deficiency in CVID. 相似文献
110.
Lucile Houyel Laurence Cohen Patrick Burlot Anne Heitzmann Damien Bonnet 《Journal of anatomy》2021,238(5):1255-1258
Anomalous connection of the inferior caval vein to the left atrium is exceedingly rare, and has even been considered by some authors an anatomic and embryologic impossibility. This study demonstrates for the first time the existence of this rare malformation, diagnosed on prenatal echo, and confirmed on post-mortem examination in a 24 WG fetus, in association with a common arterial trunk. 相似文献