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61.
62.
The antiflammatory drug indomethacin, an inhibitor of prostaglandin synthesis, prevents the generalized Shwartzman reaction produced in rabbits by two intravenous injections of bacterial endotoxin. Indomethacin has this effect if given before the first but not the second injection of endotoxin. Measurements of circulating white blood cells, platelets, partial thromboplastin time, prothrombin time, fibrinogen, plasminogen, and soluble fibrin were made at several times after either the first or second injection of endotoxin treated and nontreated rabbits. Four hours after the first injection of endotoxin, leukopenia and thrombocytopenia were somewhat greater in treated rabbits and the prolongation of the activated partial thromboplastin time was shortened. Twenty-one hours after injection of endotoxin, leukocytosis and elevation of plasma fibrinogen were not as great in treated animals. Four hours following the second injection of endotoxin a decrease in fibrinogen, prolongation of the prothrombin time, and the elaboration of soluble fibrin were consistently found in rabbits with the generalized Shwartzman reaction. In treated rabbits, none of these changes occurred. Indomethacin prevents the generalized Shwartzman reaction by preventing the development of the prepared state in this endotoxin model.  相似文献   
63.
We evaluated a simple, specific method for measuring plasma creatinine concentration, involving enzymatic degradation of creatinine before analysis by a kinetic Jaffé reaction. The enzymes--prepared in a dry, stable form--are convenient to use and eliminate the need to correct for sample dilution. As little as 50 microL of plasma is required, making the procedure ideal for use with samples from children. Between-day precision studies for determination of plasma creatinine at concentrations of 70 and 470 mumol/L yielded CVs of 7.8 and 4.3%, respectively. Analytical recovery of creatinine added to plasma samples ranged from 94 to 113%. Linear regression analysis demonstrated excellent agreement between results by this method and those by a "high performance" liquid-chromatographic technique.  相似文献   
64.
Strict isolation of vulnerable individuals has been a strategy implemented by authorities to protect people from COVID-19. Our objective was to investigate health-related quality of life (HRQoL), uncertainty and coping behaviours in solid organ transplant (SOT) recipients during the COVID-19 pandemic. A cross-sectional survey of adult SOT recipients undergoing follow-up at our institution was performed. Perceived health status, uncertainty and coping strategies were assessed using the EQ-5D-5L, Short-form Mishel Uncertainty in Illness Scale (SF-MUIS) and Brief Cope, respectively. Interactions with COVID-19 risk perception, access to health care, demographic and clinical variables were assessed. The survey was completed by 826 of 3839 (21.5%) invited participants. Overall, low levels of uncertainty in illness were reported, and acceptance was the major coping strategy (92%). Coping by acceptance, feeling protected, self-perceived susceptibility to COVID-19 were associated with lower levels of uncertainty. Health status index scores were significantly lower for those with mental health illness, compromised access to health care, a perceived high risk of severe COVID-19 infection and higher levels of uncertainty. A history of mental health illness, risk perceptions, restricted healthcare access, uncertainty and coping strategies was associated with poorer HRQoL in SOT recipients during strict isolation. These findings may allow identification of strategies to improve HRQoL in SOT recipients during the pandemic.  相似文献   
65.
BackgroundMinimal invasive surgery (MIS) is increasingly used for the correction of congenital diaphragmatic hernia (CDH) and esophageal atresia (EA). It is important to master these complex procedures, preferably preclinically, to avoid complications. The aim of this study was to validate recently developed models to train these MIS procedures preclinically.MethodsTwo low cost, reproducible models (one for CDH and one for EA) were validated during several pediatric surgical conferences and training sessions (January 2017–December 2018), used in either the LaparoscopyBoxx or EoSim simulator. Participants used one or both models and completed a questionnaire regarding their opinion on realism (face validity) and didactic value (content validity), rated on a five-point-Likert scale.ResultsOf all 60 participants enrolled, 44 evaluated the EA model. All items were evaluated as significantly better than neutral, with means ranging from 3.7 to 4.1 (p < 0.001). The CDH model was evaluated by 48 participants. All items scored significantly better than neutral (means 3.5–3.9, p < 0.001), with exception of the haptics of the simulated diaphragm (mean 3.3, p = 0.054). Both models were considered a potent training tool (means 3.9).ConclusionThese readily available and low budget models are considered a valid and potent training tool by both experts and target group participants.Type of studyProspective study.Level of evidenceLevel II.  相似文献   
66.

Endometriosis affects women of reproductive age and is associated with higher levels of sexual and relational distress. Despite the relational context of endometriosis, the research pertaining to dyadic relationship goals is lacking. An exploration of the relationship goals of couples coping with endometriosis can facilitate the understanding of potential protective mechanisms that mitigate the relational components of the condition. Guided by the approach-avoidance theoretical framework, the current cross-sectional study aimed to examine the role relationship goals play in sexual and relationship satisfaction in couples coping with endometriosis. Approach goals relate to the pursuit of a positive outcomes, whereas avoidance goals relate to the avoidance of negative outcomes. Women with endometriosis and their partners (N?=?61) completed an online survey measuring relationship goals and relationship and sexual satisfaction. The study results indicated that, for women, their own and their partner’s higher relationship approach goals were linked to higher sexual satisfaction. For partners of women with endometriosis, their own higher relationship approach goals were associated with their own higher relationship satisfaction. Higher relationship avoidance goals in both women with endometriosis and partners were associated with higher relationship satisfaction. The study’s findings highlight relationship goals as relevant to the relational and sexual experience of couples coping with endometriosis. When treating women with endometriosis, the inclusion of partners and consideration of factors beyond the physical illness are important for a holistic management approach.

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67.
68.
Osteosarcomatosis   总被引:10,自引:0,他引:10  
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized.  相似文献   
69.
This paper analyzes how economic factors (relative expected earnings, relative expected hours worked, and relative length of training period) affect the distribution of medical residents across specialties. The results show that the percent of residents in a given specialty changes more than proportionately when relative hours change (hours elasticities averaged between -1.2 and -2.0) and less than proportionately when relative earnings change (earnings elasticities averaged between 0.3 and 0.6). Residents appear to be quite unresponsive to changes in the length of training period.  相似文献   
70.
Athymic (nude) rats have been used to assess the role of thymus-dependent T cells in the control of the intestinal response following infection with the enteric parasite,Nippostrongylus brasiliensis. Tissues from infected rats were excised on days 4, 7, 10, and 21 postinfection (p-i) for physiological and morphological studies; uninfected (day 0) rats served as controls. In response to the worm burden, jejunal tissues displayed a secretory response, indicated by an elevated baseline short-circuit current (I sc ) on days 7 and 10 p-i, and were more responsive to histamine than control tissues. Despite this enhanced secretory response, 35% of the worm burden was still present on day 21 p-i (compared with expulsion of >95% by day 14 p-i in normal rats). Mast cell activation and hyperplasia, increased goblet cell (implying increased mucus synthesis) and intraepithelial leukocyte numbers, and abnormalities inI sc responses after electrical stimulation of enteric nerves were identified following infection. These events in nude rats were attenuated or delayed in onset as compared with conventional immunocompetent rats. Our results support the postulate that thymus-dependent T cells regulate the timing and/or nature of the mucosal response to enteric parasitic infections. However, ion secretion was not altered in the absence of T cells and, therefore, is more likely to be a consequence of mast cell activation.This work was conducted with financial support from The Canadian Medical Research Council and the National Institutes of Health (NS 29536).  相似文献   
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