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541.
A premature twin infant presented with clinical signs of shoulder injury shortly after birth. He had been delivered by cesarean section due to malpresentation. Bony abnormality was not initially recognized on plain radiographs, but ultrasound revealed a Salter-Harris II fracture of the proximal humerus. Plain radiographs are limited in the premature newborn because of lack of calcification of the epiphysis. Ultrasound examination in these infants can be helpful in determining the true extent of skeletal injury. Immobilization and pain control are then indicated to optimize the outcome. 相似文献
542.
A small molecule C5a receptor antagonist protects kidneys from ischemia/reperfusion injury in rats 总被引:16,自引:0,他引:16
Arumugam TV Shiels IA Strachan AJ Abbenante G Fairlie DP Taylor SM 《Kidney international》2003,63(1):134-142
BACKGROUND: C5a has been implicated in numerous pathophysiological conditions, including ischemia/reperfusion (I/R) injury of the kidney. We examined whether a novel and specific C5a receptor antagonist, the cyclic compound AcF-[OPdChaWR] could moderate I/R-induced renal injury in rats. METHODS: Female Wistar rats were subjected to renal ischemia (60 min) and reperfusion (5 h). Rats were treated with either 1 mg/kg IV in 5% ethanol/saline or 10 mg/kg PO in 25% ethanol/saline prior to ischemia. I/R injury was characterized by significant tissue hemorrhage with increased microvascular permeability, elevated renal tissue levels of tumor necrosis factor-alpha (TNF-alpha) and myeloperoxidase (MPO), increased serum levels of creatinine and aspartate aminotransferase (AST) and hematuria. RESULTS: Pre-ischemic treatment with the C5a receptor (C5aR) antagonist (1 mg/kg IV or 10 mg/kg PO) substantially inhibited or prevented I/R-induced hematuria, vascular leakage, tissue levels of TNF-alpha and MPO, and serum levels of AST and creatinine. Histological examination of kidneys from antagonist pretreated I/R animals showed a marked reduction in tissue damage compared to drug-free I/R rats. This antagonist, however, did not inhibit complement-mediated lysis of red blood cells, suggesting unimpaired formation of the membrane attack complex (MAC). CONCLUSIONS: The results demonstrate for the first time that a selective antagonist of both human and rat C5a receptors, given either intravenously or orally, significantly protects the kidney from I/R injury in the rat. We conclude that C5a is an important pathogenic agent in renal I/R injury, and that C5a receptor antagonists may be useful therapeutic agents for the pretreatment of anticipated renal reperfusion injury in humans. 相似文献
543.
BACKGROUND: Little research has focused upon how GP and patient gender interact to influence the outcome of consultation. In particular, no UK studies have investigated the effect of gender interaction on the duration of patients' certified sickness. OBJECTIVE: To investigate associations between the four GP-patient gender interaction categories and patient risk of intermediate or long-term work incapacity. METHODS: Design: Use of carbonized sickness certificates to collect routine sick note data over a 12-month collection period. Setting: Nine general practices in the Mersey Primary Care R&D Consortium. Subjects: A total of 3906 patients, certified sick by 67 GPs (including 45 GP principals). Main outcome measures: The effect of gender interaction was measured against two outcomes: intermediate (6-28 week) and long-term (28 weeks or over) periods of certified sickness. RESULTS: After univariate and multivariate analyses, it was discovered that certification of male patients by male GPs was significantly associated with increased prevalence of intermediate (6-28 week) certified sickness outcomes, compared with females certified by females (OR=1.38 P=0.009). This result was replicated in the subgroup of patients with mild mental disorder-related sickness absence. However, no association was demonstrated between gender interaction and long-term (>or=28 week) outcome, in the total patient group or within diagnostic subcategories. CONCLUSION: GP and patient gender appear to have most impact upon sickness certification in the intermediate period. This period is already recognized as the optimum time for interventions to prevent onset of long-term incapacity, particularly in cases where the cause of sickness absence is reversible (as in psychological-related certified sickness absence). Further research is needed (particularly focusing upon attitudes and content of consultations) in order to shed more light on the gender differences found in this study. 相似文献
544.
Mair FS Goldstein P Shiels C Roberts C Angus R O'Connor J Haycox A Capewell S 《Journal of telemedicine and telecare》2006,12(Z1):26-28
We analysed the difficulties encountered in recruiting predominantly older patients, suffering from an acute exacerbation of a chronic illness, to a randomized controlled trial of home telecare. Of 653 patients approached for study participation, after full assessment, 80% (519) met the trial eligibility criteria. Of these, 104 (20%) consented to study participation and 415 (80%) refused. A logistic regression model was constructed to examine independent effects of patient factors on probability of trial participation. Only two independent variables were associated with decreased likelihood of consent: increasing age (1 year older: odds ratio [OR] = 0.96); and being on inhaled steroid medication (OR = 0.60). The most common reason for refusal to participate, accounting for almost one-third of respondents, was a stated preference for a face-to-face nurse visiting service rather than a telecare service. Perhaps home telecare services should continue to be targeted at the more stable chronically ill population and not at those suffering from acute illness. 相似文献
545.
Mair FS Goldstein P May C Angus R Shiels C Hibbert D O'Connor J Boland A Roberts C Haycox A Capewell S 《Journal of telemedicine and telecare》2005,11(Z1):95-97
A randomized controlled trial of home telecare for the management of acute exacerbations of chronic obstructive pulmonary disease has been undertaken in the north-west of England. A videophone was used that communicates via the ordinary telephone network. The intervention period for each participant was two weeks. Participants in the telecare arm of the trial were asked to complete logbooks to record their experiences of each telecare encounter. A simple, self-completed, 10-item questionnaire was used that consisted of a Likert scale, ranging from 1 (totally disagree) to 5 (totally agree). Fourteen nurses completed 150 logbooks and 22 patients completed 145 logbooks. These results demonstrate significant differences in perception between patients and their health-care providers with regard to telecare encounters across all the domains addressed. Participating patients consistently demonstrated more positive views of the telecare encounters than their healthcare providers. 相似文献
546.
Regulation of aquaporin water permeability in the lens 总被引:6,自引:0,他引:6
Varadaraj K Kumari S Shiels A Mathias RT 《Investigative ophthalmology & visual science》2005,46(4):1393-1402
PURPOSE: To examine Ca(2+)- and pH-mediated regulation of water permeability of endogenously expressed aquaporin (AQP)0 in lens fiber cells and AQP1 in lens epithelial cells. METHODS: Large, right-side-out membrane vesicles were formed from freshly isolated groups of lens fiber cells. Osmotic shrinking or swelling of these vesicles was used to determine the water permeability of endogenously expressed AQP0. The results were compared with those in similar studies of freshly isolated lens epithelial cells, which endogenously expressed AQP1, and of oocytes, which exogenously expressed AQP0. RESULTS: In the lens or in oocytes, decreasing external pH from 7.5 to 6.5 caused a two- to fourfold increase in the water permeability of mammalian AQP0. Several lines of evidence suggest that this effect is mediated by the binding of H(+) to a histidine in the first extracellular loop (His40). Lens AQP1 lacks His40 and also lacks pH sensitivity. Increasing Ca(2+) caused a two- to fourfold increase in the water permeability of endogenous AQP0. The Ca(2+) effect on mouse AQP0 was a 2.5-fold increase in the lens, whereas in oocytes, it was a 4-fold decrease. In either environment, the effect was mediated through calmodulin, most likely through its binding to the proximal domain of the C terminus. Lens AQP1 does not have a similar domain and does not have calcium sensitivity. CONCLUSIONS: In either the lens or oocytes, Ca(2+) and H(+) appear to affect the same mechanism, probably either the open probability of the water channel, or open-channel permeability. The difference between calcium's effects in lens versus oocytes was remarkable and is not understood. However, in the lens, Ca(2+) and H(+) are both increased in inner fiber cells, and so in the physiologically relevant environment, both may act to increase the water permeability of AQP0. 相似文献
547.
548.
van Leeuwen A; Schrier PI; Giphart MJ; Noordermeer IA; Ruiter DJ; Rubinstein P; van Rood JJ 《Blood》1986,67(4):1139-1142
TCA (T Cell system A) is a di-allelic system of HLA-like antigens encoded by genes located about 15 cM telomeric to HLA-A. In normal individuals, TCA antigens are only expressed on a subpopulation of T cells, the TG lymphocytes. We now report on the expression of TCA on leukemias and other malignancies. An increased proportion of cells carrying the TCA phenotype was encountered in testing peripheral blood lymphocytes from patients with acute lymphoblastic T-cell leukemia (T- ALL), acute myeloid leukemia (AML), and chronic myeloid leukemia (CML). In contrast, patients with B-cell malignancies such as chronic lymphatic leukemia (CLL) and hairy cell leukemia (HCL) or non-T/non-B common acute lymphoblastic leukemia (common ALL) had normal proportions of TCA-positive lymphocytes. Quantitatively different levels of TCA expression are found on some melanoma cell lines and others are TCA negative. These variations are independent of the expression of HLA Class I antigens by the same cells. The expression of TCA antigens by malignant nonlymphoid cells suggests that this system may code for differentiation markers, important in the biology of neoplastic transformation. 相似文献
549.
550.