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61.
Mast cell degranulation and parenchymal cell injury in the rat mesentery.   总被引:1,自引:0,他引:1  
OBJECTIVE: The objective of this study was to explore the degree of parenchymal cell injury after mast cell degranulation by application of compound 48/80 (CMP 48/80) in the absence of adherent leukocytes in the rat mesentery. METHODS: Rats were rendered leukopenic by injection of an antibody against leukocytes, and the mesentery was superfused with CMP 48/80 during intravital microscopy. The extent of cell injury was determined using a fluorescent cell-viability indicator, propidium iodide (PI). In an additional group, mast cell degranulation with CMP 48/80 was prevented by using the mast cell stabilizer Ketotifen. RESULTS: After a reduction in the number of circulating leukocytes, mast cell degranulation produced a mild increase in parenchymal cell injury. The injury levels significantly increased when individual regions of the mesentery were compared. Stabilization of the mast cells with Ketotifen reduced the injury to below baseline values. CONCLUSIONS: In the absence of leukocyte adhesion to the endothelium, mast cell degranulation contributes to parenchymal cell injury in the mesentery.  相似文献   
62.
Aim The primary aim of this investigation was to examine genotype and clinical phenotype differences in individuals with juvenile neuronal ceroid lipofuscinosis (JNCL) who were homozygous for a common disease‐causing deletion or compound heterozygous. The secondary aim was to cross‐validate the Child Behavior Checklist (CBCL) and the Unified Batten Disease Rating Scale (UBDRS), a disease‐specific JNCL rating scale. Method Sixty individuals (28 males, 32 females; mean age 15y 1mo, SD 4y 9mo, range 5y 8mo–31y 1mo) with JNCL completed the UBDRS. Results No significant genotype and clinical phenotype differences were identified when comparing individuals homozygous for the deletion with a heterogeneous group of compound heterozygous individuals. There were significant correlations among related behaviour items and scales on the CBCL and UBDRS (Spearman’s rho ranging from 0.39 [p<0.05] to 0.72 [p<0.01]). Behaviour and physical function ratings were uncorrelated, supporting divergent validity of these two constructs in JNCL. Interpretation Previous reports of genotype and clinical phenotype differences were unsupported in this investigation, which did not find differences between individuals homozygous or heterozygous for the CLN3 deletion. The CBCL, an already validated measure of behaviour problems, appears valid for use in JNCL and cross‐validates well with the UBDRS.  相似文献   
63.
Policy Points
  • Medicaid policymakers have a growing interest in addressing homelessness as a social determinant of health and driver of the potentially avoidable use of expensive medical services.
  • Drawing on extensive document reviews and in‐depth interviews in four early‐adopter states, we examined the implementation of Medicaid''s Section 1115 demonstration waivers to test strategies to finance tenancy support services for persons experiencing or at risk of homelessness.
ContextThe Affordable Care Act extended Medicaid eligibility to large numbers of individuals experiencing or at risk of homelessness. This legislative development and the growing recognition of homelessness as a significant social determinant of health have encouraged advocates and policymakers to seek new ways to use Medicaid to provide housing supports.MethodsWe conducted 28 semistructured interviews with 36 stakeholders in four states. The stakeholders were government administrators, health care providers, nonprofit housing staff, and consultants. We supplemented these interviews with extensive reviews of public documents, media accounts, think‐tank reports, and published literature. We also conducted a systematic inductive qualitative analysis.FindingsWe identified seven challenges to the successful implementation of tenancy support demonstration projects: resolving the housing supply and NIMBY, removing silos between health care and homeless services providers, enrolling and retaining the target populations in Medicaid, contracting with and paying tenancy support providers, recruiting and retaining key workers, ensuring Medicaid''s waiver durability, and reducing administrative crowd‐out and waiver burden.ConclusionsNotwithstanding these challenges, three of the four states have made significant progress in launching their initiatives. At this point, the fourth state has delayed its start‐up to consider alternatives to a Medicaid demonstration waiver to provide tenancy supports. The experience of the four states suggests lessons for Medicaid officials in other jurisdictions that are interested in pursuing tenancy support initiatives. Nevertheless, the limitations of tenancy support waiver programs suggest that federal policymakers should consider allowing states to more directly subsidize housing costs for those experiencing or at risk of homelessness as an optional Medicaid benefit.  相似文献   
64.
Infra-red thermography was used to quantify, at patch test sites, the allergic responses to experimental preparations of nickel sulphate and primary irritant responses to sodium lauryl sulphate in small groups of volunteers. The technique was also used to assess the patch-test responses in a much larger group of patients who had undergone routine patch testing for contact allergy with a wide range of test substances and among which there were large numbers of allergic, irritant and equivocal reactions. Thermographically, when compared to the surrounding normal skin surface, the sites of allergic reactions appeared as hot areas, the temperature and area of which were apparently dependent on the severity of the response. For allergic responses, there was a good correlation between the clinical assessment and either of two thermographic parameters, temperature and area of involvement. Compared with an aqueous solution of nickel sulphate, 'poor' formulations of the allergen, such as a suspension in soft paraffin base, elicited smaller and cooler reactions. Irritant reaction sites were not 'hot' and the temperature at such sites was no different from that of the surrounding normal skin. Infra-red thermography is a convenient non-invasive technique which apparently can be used to discriminate between irritant and allergic responses and to quantify the latter type of response.  相似文献   
65.
BACKGROUND: Confidence is an important factor in decision making and may influence patient care. OBJECTIVES: To evaluate whether short-training-based dermoscopy increases confidence in the diagnosis of skin lesions. METHODS AND MATERIALS: After a 1-hour course on dermoscopy, 20 pairs of clinical and dermoscopic images of lesions were presented to 19 dermatology residents with little or no dermoscopy experience. After viewing the clinical image, they were asked to assess their confidence in the diagnosis in a seven-point scale, with 1 reflecting that the respondent was 100% confident that the lesion was benign, while number 7 reflected 100% confidence that it was malignant. The same technique was used for dermoscopic images. RESULTS: Ten of the 20 pairs of evaluations showed a significant difference (p<.05). The largest differences were observed in lesions where clinical scores suggested that participants were uncertain about the diagnosis, but tended to decide that the lesion was benign after dermoscopy. Dermoscopy did not improve confidence in the evaluation of dysplastic lesions as well as lesions with obvious clinical diagnoses. CONCLUSIONS: Short-training-based dermoscopy improved confidence in the diagnosis of clinically challenging skin lesions, but the impact was not demonstrable for clinically obvious lesions and dysplastic nevi.  相似文献   
66.
Vascular filling defects are a normal feature of the thoracic myelogram. The aim of this paper was to provide criteria for differentiating the vascular filling defects in spinal AVM's from the range of filling defects seen in non-AVM patients. Out of 940 consecutive thoracic myelograms, in non-AVM patients, 505 had vascular filling defects. These were compared with the myelographic features of nine spinal AVM's, with regard to vessel diameter, length, tortuosity and number. None of these criteria were diagnostic of AVM's as there was overlap bet ween the vascular filling defects of AVM's and the range of normal spinal cord vessels, especial ly posterior spinal veins. However, filling defects greater than 1.4 mm diameter, which are excessively tortuous, long and. multiple, should be regarded as highly suspinous of an AVM. A lateral film is important when vascular filling defects are seen, for if these filling defects are anterior to the cord, an AVM is more likely.  相似文献   
67.
Spontaneous bacterial peritonitis   总被引:1,自引:0,他引:1  
  相似文献   
68.
Acropustulosis of infancy is a syndrome characterized by recurrent pruritic acral vesicopustules. It occurs primarily in black male infants and hitherto has been described mainly in the North American literature. We describe four cases seen in London. This entity, therefore, should be recognized in the U.K., particularly in the differential diagnosis of infantile scabies.  相似文献   
69.
Introduction: Popping, char and perforation are complications that can occur following catheter ablation. We measured the amount of grams (g) applied to the endocardium during ablation using a sensor incorporated in the long sheath of a robotic system. We evaluated the relationship between lesion formation, pressure, and the development of complications.
Methods: Using a robotic navigation system, lesions were placed in the left atrium (LA) at six settings, using a constant duration (40 seconds) and flow rate of either 17 cc/min or 30 cc/min with an open irrigated catheter (OIC). Evidence of complications was noted and lesion location recorded for later analysis at necropsy.
Results: Lesions using 30 Watts (W) were more likely to be transmural at higher (>40 g) than lower (<30 g) pressures (75% vs 25%, P < 0.001). Significantly higher number of lesions using >40 g of pressure demonstrated "popping" and crater formation as compared with lesions with 20–30 g of pressure (41% vs 15%, P = 0.008). A majority of lesions placed using higher power (45 W) with higher pressures (>40 g) were associated with char and crater formation (66.7%). No lesions using 10 g of pressure were transmural, regardless of the power. Lesions placed with a power setting less than 35 W were more likely to result in "relative" sparing of the endocardial surface than lesions at a power setting higher than 35 W (62% vs 33.3%, P = 0.02) regardless of the pressure.
Conclusions: When using an OIC, lower power settings (≤35 W) and lower/medium contact pressure were more likely to show a "relative" spared endocardial surface. Overall, contact pressure between 20 g and 30 g and a power setting of 40 W appeared to achieve transmurality by preserving safety.  相似文献   
70.
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