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991.
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Journal of Thrombosis and Thrombolysis - The complement system (CS) plays a pivotal role in Coronavirus disease 2019 (COVID-19) pathophysiology. The objective of this study was to...  相似文献   
993.
994.
In vivo data suggest a role of LTD4 in mediating endotoxin (LPS)-inducible liver injury in galactosamine-sensitized mice. Leukotriene D4 (LTD4) was shown to synergize in this model with subtoxic amounts of LPS in inducing hepatitis. Mice challenged i.v. with a subtoxic dose of LPS [50 ng/kg] showed significant TNF serum levels 90 min later which were sixfold increased by coadministration of 50 g/kg LTD4. When rat Kupffer cells were challenged with LPS, TNF- measured in the supernatant was significantly increased by LTD4 [100 pg–100 ng/ml]. Addition of LTD4 alone did not result in any detectable TNF formation.Since Kupffer cells are known producers of small amounts of LTD4, it seems feasible that LTD4 represents an autocrine stimulus of nonparenchymal liver cells. In fact, different LTD4 synthesis inhibitors and receptor antagonists attenuated LPS-inducible TNF release of rat Kupffer cells supporting the conclusion that LTD4 acts as an endogenous autocrine enhancer of liver macrophage TNF release.  相似文献   
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We examine the interaction in the market for physician services when the total budget for reimbursement is fixed. Physicians obtain points for the services they render. At the end of the period the budget is divided by the sum of all points submitted, which determines the price per point. We show that this retrospective payment system involves -- compared to a fee-for-service remuneration system -- a severe coordination problem, which potentially leads to the "treadmill effect". We argue that when market entry is possible, a budget can be efficiency enhancing, if in addition a price floor is used.  相似文献   
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998.
A 16-year-old girl presented signs of a common cold in combination with a hemolytic crisis. Within 3 days, she developed reduced consciousness and hemiparesis subsequently followed by coma. CT and MRI scans revealed evidence for raised intracranial pressure and an extensive inflammatory process extending from the brain stem up to the thalamus. The patient died within 3 weeks after onset of first symptoms of intracranial pressure despite maximum intensive care. Neuropathological examination revealed disseminated necrotic lesions and perivascular hemorrhages characteristic for acute hemorrhagic leukoencephalitis (Hursts disease), mainly of the brain stem, diencephalon and cerebellum. Serological results, in situ hybridization and PCR analysis demonstrated an acute Epstein-Barr virus (EBV) infection of the central nervous system. To our knowledge, this is the first reported case of Hursts disease linked to EBV.  相似文献   
999.
PURPOSE: The purpose of this study was to evaluate the potential of the new 8G stereotactic vacuum-assisted breast biopsy (ST-driver, Mammotome; Ethicon Endosurgery) in the histologic evaluation of BI-RADS IV microcalcifications. MATERIALS AND METHODS: Fifty-eight patients with 61 mammographic BI-RADS IV microcalcifications underwent stereotactic vacuum-assisted breast biopsy (SVAB). The new 8G system was mounted on the ST driver, which was formerly used only with the hand-held version under sonographic guidance. The evaluation criteria for each biopsy were minimally invasive and operative histologies, the time needed for biopsy, the amount of bleeding, number of rotations and specimen, the degree of resection, and the complications. RESULTS: Fifty-eight of 61 biopsies were technically successful because > or = 50% were resected (29 x 100%, 8 x 90%, 5 x 80%, 6 x 70%, 3 x 50%, 3 x 0%). In 7 cases with representative biopsies of segmental suspicious microcalcifications, the degree of resection could not be exactly measured. All but 2 biopsies were performed without clinically relevant complications and after gaining enough specimens (? 12.6 specimen, 1.85 rotations). Those 2 patients showed evidence of severe bleeding into the breast tissue and operative revision had to be performed (3.5%). The size of intramammary hematoma was measurable in 27 biopsies and showed a range from 0.5 to 5 cm (? 2.7 cm). The average external bleeding was still low with 16 mL (5-80 mL). In 3 of 61 lesions, it was not possible to gain representative tissue as a result of displacement of the lesion after introducing or shooting the needle. The average time needed for all biopsies was 28.2 minutes for all but 5 very complicated biopsies, which took 16.1 minutes. The histologic findings with further operative workup were: 10 ductal carcinomas in situ (DCIS), 4 atypical ductal hyperplasias, 1 atypical lobular hyperplasias (ALH), 3 lobular carcinomas in situ (LCIS), and 6 invasive ductal carcinomas. In 7 of 12 of the initial DCIS histologies, the operative histology was also DCIS, whereas in 4 of 12, no residual malignant tumor was found. In 1 of 12 patients with an initial DCIS histology, operative histology revealed invasive ductal cancer (8.3%). The cases with lobular lesions (ALH, LCIS) did not show any evidence for residual tissue in the operative workup. Most frequent benign histologies were mastopathy (13), ductal hyperplasia (9), fibroadenoma (8), and sclerosing adenosis (5). The control examinations (maximum 1 year) did not show any signs for a false-negative biopsy. CONCLUSION: The 11-G SVAB has proven to be a perfect adjunct to the existing breast biopsy methods. The new 8G SVAB speeds up the method when used for the same size of lesions and enables the user to representatively biopsy lesions up to 3 cm in diameter. The method is still minimally invasive; however, the amount of hematomas as well as clinically relevant complications is increased.  相似文献   
1000.
PURPOSE: To determine clinical predictors of cervical spine fracture in the elderly and to develop a clinical prediction rule to guide appropriate imaging in high-risk patients. MATERIALS AND METHODS: Institutional review board approval was received with waiver of informed consent. A retrospective case-control study was performed on blunt trauma patients 65 years and older with cervical spine fractures and on randomly selected control subjects without fracture. Potential predictors of fracture were evaluated through simple and multivariate logistic regression. Simple predictors were grouped into clinically similar composite variables and were analyzed with multivariate logistic regression and recursive partitioning. A clinical prediction rule was generated. The receiver operating characteristic curve was calculated and adjusted through bootstrap validation. Absolute cervical spine fracture probabilities were calculated by using Bayes theorem for all elderly patients and for patients who underwent computed tomography. Results were compared with a previous prediction rule for all adults. RESULTS: Composite predictors of fracture in the elderly included focal neurologic deficit (adjusted odds ratio, 17.7; 95% confidence interval [CI]: 3.8, 83.4), severe head injury (odds ratio, 3.2; 95% CI: 1.5, 7.1), high-energy mechanism (odds ratio 6.7; 95% CI: 3.1, 14.8), and moderate-energy mechanism (odds ratio 3.3; 95% CI: 1.3, 8.3). The prediction rule stratified patients into risk groups with fracture probabilities ranging from 0.4% (95% CI: 0.1%, 1.3%) to 24.2% (95% CI: 5.7%, 100%). CONCLUSION: Clinical factors can be used to stratify patients 65 years and older into risk groups with a wide range of probabilities of cervical spine fracture. Knowledge of cervical fracture risk can help guide appropriate imaging in high-risk patients.  相似文献   
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