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61.
62.
The epidemiology of traumatic rupture of the thoracic aorta in children: a 13-year review 总被引:1,自引:0,他引:1
A C Eddy V W Rusch C L Fligner D T Reay C L Rice 《The Journal of trauma》1990,30(8):989-91; discussion 991-2
Traumatic rupture of the thoracic aorta (TRA) is a rare but highly lethal injury in children that occurs as a result of car versus pedestrian accidents and motor vehicle accidents. TRA is often associated with life-threatening injuries to other organ systems. Therefore children with TRA like adults sustaining TRA must be treated urgently but systematically. The rarity of this injury makes it all the more important for physicians treating pediatric trauma victims to be cognizant of the importance of the injury and the clinical and radiographic signs. Even when TRA is promptly recognized in children it is associated with a high in-hospital mortality. The proper use of child restraint systems and adherence to the 55 M.P.H. speed limit may be important factors in reducing the mortality of TRA in children after MVA. 相似文献
63.
There are three principal malignant vasoformative tumors that can be found in the head and neck--hemangiopericytoma, angiosarcoma, and Kaposi's sarcoma. All are uncommon and provide challenges for the pathologist and the therapist both. The histogenesis of each tumor is different. Kaposi's sarcoma has many features which suggest that it is an altered immune-response disease. Angiosarcoma is a malignancy of endothelium. Hemangiopericytoma is a tumor whose cell of origin is considered to be the perithelial pericyte. The general prognosis for patients with Kaposi's sarcoma is good. The biologic course of a hemangiopericytoma is variable and unpredictable, but there appears to be a site dependency. Angiosarcomas, particularly high grade lesions, are resistant to therapy. 相似文献
64.
Promoting effects of sodium salts of phenobarbital (NaPB) and barbital (NaBB) on the development of bladder tumors were investigated in F344 male rats initiated with N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) or N-nitrosobutyl-4-hydroxybutylamine (BBN). To initiate with FANFT, rats were fed 0.2% FANFT mixed in diet for either 2 or 6 weeks and 2 weeks later were offered diet containing 1000 ppm of NaPB or NaBB. Rats were killed either at 52 or 68 weeks of age. To initiate with BBN, rats were given 0.05% BBN in drinking water for 4 weeks and beginning 1 day later were fed NaBB mixed in diet at 1000 ppm for up to 52 weeks. NaBB promoted bladder carcinogenesis initiated by either FANFT or BBN; the incidence and average number of simple or preneoplastic nodular (PN) hyperplasias, papillomas, and carcinomas per 10 cm of urothelium were significantly increased in the groups receiving NaBB following exposure to FANFT for 6 weeks (p less than 0.05) or BBN for 4 weeks (p less than 0.01). No such effect was seen in rats fed FANFT for only 2 weeks. NaPB also significantly increased (p less than 0.05) the frequency of preneoplastic PN hyperplasias but not the average number of papillomas and carcinomas per 10 cm of urothelium in rats fed FANFT for 6 weeks. NaBB was an effective promoter of bladder carcinogenesis under these experimental conditions, as expected from its known promoting effect on transitional epithelium of the renal pelvis, but NaPB in contrast did not affect the incidence or multiplicity of bladder papillomas or carcinomas under these conditions. NaPB could be considered a promoter for bladder urothelium only by the less rigorous criterion that it increased the frequency of preneoplastic PN hyperplasia. 相似文献
65.
R B Rothman V Bykov A Reid B R De Costa A H Newman A E Jacobson K C Rice 《Neuropeptides》1988,12(3):181-187
Norbinaltorphimine (nor-BNI) is a bifunctional reagent developed as a selective antagonist of the kappa opioid receptor. In this paper we examined the in vitro selectivity of nor-BNI, 6-desoxy-6 beta-fluoronaltrexone (cycloFOXY), and the enantiomer of cycloFOXY, among opioid receptor subtypes. Nor BNI exhibited the highest affinity for kappa binding sites labeled by 3H-U69593 (Ki = 1.8nM), and was 27- to 29-fold less potent at mu and delta binding sites. In contrast, cycloFOXY had the highest affinity for mu binding sites (Ki = 2.62 nM), and bound to kappa and delta binding sites with Ki's of 9.3 nM and 89 nM, respectively. The enantiomer of cycloFOXY, did not inhibit binding even at concentrations greater than 10 microM, validating in part the use of 18F-labeled (+)-cycloFOXY to estimate "non-specific binding" in positron emission tomography. Additionally, we report that (S,S)-U50 488 and (R.R)-U50 488 bind to kappa binding sites labeled by 3H-U69 593 with Ki's of 0.89 nM and 299 nM, respectively. 相似文献
66.
J P Rice N Rochberg J Endicott P W Lavori C Miller 《Archives of general psychiatry》1992,49(10):824-830
In the National Institute of Mental Health Collaborative Program on the Psychobiology of Depression study, data were collected on 2226 first-degree relatives of 612 probands. A second, "blind" reassessment of all relatives was attempted 6 years after the initial evaluation. We report on a final sample of 1629 relatives assessed twice using the Schedule for Affective Disorders and Schizophrenia-Lifetime version. We summarize methods for using stability of diagnosis to model the relationship between clinical covariates and the probability of being a true case. Moreover, we define an index of caseness that can be used to narrow the criteria for who is a case. Of those positive for major depressive disorder at initial evaluation, 74% were positive (on a lifetime basis) at follow-up (ie, were stable). There is a gradient: 48% of those who had three symptoms and no treatment were stable, compared with 96% of those with eight symptoms and treatment. For major depressive disorder, we found the caseness index for those with lifetime mania more severe than that of nonbipolar patients, with those who had hypomania being intermediate. A hierarchical analysis indicated that bipolar I tends to be diagnosed as schizoaffective-manic across occasions, and vice versa. This is consistent with the prior familial analyses that suggest these two diagnoses be combined into a single bipolar phenotype. The analysis for major depressive disorder indicates that caseness appears to represent quantitative, rather than qualitative, differences, with no natural cutoff to identify distinct subgroups. Finally, we discuss implications including utility in genetic analyses, estimation of incidence or prevalence allowing for diagnostic error, and examination of cohort effects. 相似文献
67.
S Vijayakumar K Shepard F Thomas J Weick T Rice A Mehta 《Journal of the National Medical Association》1987,79(5):496-504
The role of radiotherapy in small cell carcinoma of the lung is unsettled; however, the radiosensitivity of this neoplasm is unquestioned. The ability of radiotherapy to cure or improve patients with this disease is still undergoing study. A review of this challenging subject is presented. 相似文献
68.
Giardia lamblia cysts obtained from human symptomatic and asymptomatic donors were excysted in vitro. Excystation averaged 87% for cysts from symptomatic donors and 70% for cysts from asymptomatic donors. 相似文献
69.
Airway eosinophilia and expression of interleukin-5 protein in asthma and in exacerbations of chronic bronchitis 总被引:6,自引:0,他引:6
M. SAETTA A. DI STEFANO P. MAESTRELLI G. TURATO CE. MAPP M. PIENO G. ZANGUOCHI G. DEL PRETE† L. M. FABBRI 《Clinical and experimental allergy》1996,26(7):766-774
Background An increased nutnber of eosinophils in the bronchial mucosa has been demonstrated both in asthma and in exacerbations of chronic bronchitis. Oiyective To investigate whether the airway eosinophilia present in asthma and in chronic bronchitis during exacerbations is associated with interleukin (IL)-5 protein expression in the bronchial mucosa. Methods We obtained bronchial biopsies in 18 subjects with asthma (four intrinsic, seven extrinsic and seven occupational) and in II subjects with chronic bronchitis examined during an exacerbation. The findings were compared wilh those of bronchial biopsies from 10 subjects with chronic bronchitis examined under baseline conditions and from seven normal subjects, taken as controls. By immunohistochemistry, we assessed the expression of IL-5 protein and the number of eosinophils (EG2), mast cells ftryptase), and T-lymphocytes (CD3) in the submucosa. Results As compared with controls, the number of eosinophils was increased to a similar degree in both asthma (P < 0.001) and in exacerbations of ehronic bronchitis (P < 0.001). whereas the number of I L-5 immunopositive cells was increased significantly only in asthma (P < 0.01). No diflerences were observed in the number of tnast cells and T-lymphocytes between the four groups of subjects examined. Conciusions This study shows that the degree of airway eosinophilia is similar in asthma and in exacerbations of ehronic bronchitis, but only in asthma is it associated with an increased expression of I L-5 protein in the bronchial tnucosa. 相似文献
70.
Opsonin-dependent and independent surface phagocytosis of S. aureus proceeds independently of complement and complement receptors. 总被引:3,自引:0,他引:3 下载免费PDF全文
We examined the mechanism of surface phagocytosis of Staphylococcus aureus by human polymorphonuclear leucocytes (PMN). Surface phagocytosis of unopsonized bacteria occurred, but was significantly enhanced by the presence of serum. The serum requirement was low, and a maximal effect occurred with serum concentrations of 0.25-0.5%. The opsonic effect of serum was not removed by heat inactivation of complement but was adsorbed, at low serum concentrations, by protein A, indicating that opsonin-dependent surface phagocytosis requires IgG but not C3. The requirement of opsonin-dependent surface phagocytosis for IgG was demonstrated further with purified IgG preparations as the sole opsonin. Activation of PMN by N-formyl-methionyl-leucyl-phenylalanine (FMLP) or phorbol myristate acetate (PMA) increased opsonin-independent surface phagocytosis by 47% and 66%, respectively, but had no effect on opsonin-dependent surface phagocytosis. Blockade of the PMN iC3b receptor (CR3), which has lectin-like properties, by a panel of monoclonal antibodies against the alpha- and beta-chains of CR3 did not inhibit the surface phagocytosis of opsonized or unopsonized S. aureus, and one antibody (NIMP-R10) enhanced opsonin-independent surface phagocytosis. These results indicate that the mechanism of surface phagocytosis is quite different to that observed in suspension assays. Opsonin-independent surface phagocytosis occurs and is enhanced by PMN activation, opsonin-dependent surface phagocytosis is dependent on IgG and not complement, and neither opsonin-independent nor -dependent surface phagocytosis proceeds through CR3. 相似文献