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991.
Five patients with chronic traumatic diaphragmatic hernia presented with symptoms of acute intestinal obstruction and unilateral pleural effusion. In each case, infarcted herniated abdominal structures were found at surgery. The presence of an ipsilateral pleural effusion is an important radiographic sign, which may indicate strangulation in patients with chronic traumatic diaphragmatic hernia. 相似文献
992.
A method to decrease the intensity of fat by reversal of the section-select gradient is demonstrated. This technique takes advantage of the chemical shift in section location. 相似文献
993.
Rigauts HD; Selleslag DL; Van Eyken PL; Van Damme BJ; Fevery JM; Marchal GJ 《Radiology》1988,169(3):661-662
A 67-year-old patient was admitted with a 2-week history of epigastric discomfort that began after an episode of upper respiratory tract infection treated with erythromycin. Results of liver function tests were abnormal. Abdominal ultrasound (US) and computed tomography showed multiple, poorly demarcated irregular lesions in both hepatic lobes, suggestive of diffuse metastatic invasion. Histologic examination of the biopsy specimen revealed drug-induced hepatitis. Ten weeks after withdrawal of the erythromycin, US showed complete resolution of the hyperechogenic liver lesions. 相似文献
994.
Intracranial hemorrhage: gradient-echo MR imaging at 1.5 T. Comparison with spin-echo imaging and clinical applications 总被引:9,自引:0,他引:9
Fifty-seven patients with hemorrhagic intracranial lesions were examined with magnetic resonance (MR) imaging at 1.5 T with use of both spin-echo (SE) and gradient-echo-acquisition (GEA) techniques to assess the clinical applications and limitations of GEA in evaluation of intracranial hemorrhage at high field strength. All GEA images were obtained with a long echo time and short flip angle to emphasize T2*-based contrast. In 30 of 61 cases, GEA images demonstrated more hemorrhagic lesions than SE images. In 14 of 61 cases, GEA images failed to depict the lesion or obscured the specific diagnosis (as depicted by SE MR imaging). The authors believe that GEA imaging in its current form has a limited but definite adjunctive role in the evaluation of intracranial hemorrhage at high field strength. 相似文献
995.
Potential hearing loss resulting from MR imaging 总被引:4,自引:0,他引:4
To determine if the loud noise generated by magnetic resonance (MR) imaging equipment is capable of inducing hearing loss, the hearing of 24 patients was tested before and after MR imaging. Fourteen patients were imaged without ear protection, and six (43%) suffered a temporary, mild loss of hearing (less than or equal to 15 dB at at least one frequency). Ten patients were imaged with ear protection, and only one experienced any hearing loss. Therefore, the noise generated by MR imagers may cause temporary hearing loss, and earplugs can prevent this loss. All threshold changes had returned to within 10 dB of baseline by 15 minutes after completion of the second audiometric test. 相似文献
996.
AR Weinstein HD Sesso IM Lee NR Cook JE Manson JE Buring JM Gaziano 《JAMA : the journal of the American Medical Association》2004,292(10):1188-1194
CONTEXT: Physical inactivity and body mass index (BMI) are established independent risk factors in the development of type 2 diabetes; however, their comparative importance and joint relationship with diabetes are unclear. OBJECTIVE: To examine the relative contributions and joint association of physical activity and BMI with diabetes. DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort study of 37 878 women free of cardiovascular disease, cancer, and diabetes with 6.9 years of mean follow-up. Weight, height, and recreational activities were reported at study entry. Normal weight was defined as a BMI of less than 25; overweight, 25 to less than 30; and obese, 30 or higher. Active was defined as expending more than 1000 kcal on recreational activities per week. MAIN OUTCOME MEASURE: Incident type 2 diabetes, defined as a new self-reported diagnosis of diabetes. RESULTS: During the follow-up, 1361 cases of incident diabetes occurred. Individually, BMI and physical activity were significant predictors of incident diabetes. Compared with normal-weight individuals, the multivariate-adjusted hazard ratio (HR) was 3.22 (95% confidence interval [CI], 2.69-3.87) for overweight individuals and 9.09 (95% CI, 7.62-10.8) for obese individuals. For overall activity (kilocalories expended per week), compared with the least active first quartile, the multivariate-adjusted HRs were 0.91 (95% CI, 0.79-1.06) for the second quartile, 0.86 (95% CI, 0.74-1.01) for the third, and 0.82 (95% CI, 0.70-0.97) for the fourth (P for trend =.01). In the combined analyses, overweight and obese participants, whether active or inactive, had significantly elevated risks, compared with normal-weight active individuals. The multivariate-adjusted HRs were 1.15 (95% CI, 0.83-1.59) for normal-weight inactive, 3.68 (95% CI, 2.63-5.15) for overweight active, 4.16 (95% CI, 3.05-5.66) for overweight inactive, 11.5 (95% CI, 8.34-15.9) for obese active, and 11.8 (95% CI, 8.75-16.0) for obese inactive participants. CONCLUSIONS: Although BMI and physical inactivity are independent predictors of incident diabetes, the magnitude of the association with BMI was greater than with physical activity in combined analyses. These findings underscore the critical importance of adiposity as a determinant of diabetes. 相似文献
997.
JM Danger MC Tonon BG Jenks S. Saint-Pierre JC Martel A. Fasolo B. Breton R. Quirion G. Pelletier and H. Vaudry 《Fundamental & clinical pharmacology》1990,4(3):307-340
Neuropeptide Y (NPY) is a 36-amino acid peptide first isolated and characterized from porcine brain extracts. A number of immunocytochemical investigations have been conducted to determine the localization of NPY-containing neurons in various animal species including both vertebrates and invertebrates. These studies have established the widespread distribution of NPY in the brain and in sympathetic neurons. In the rat brain, a high density of immunoreactive cell bodies and fibers is observed in the cortex, caudate putamen and hippocampus. In the diencephalon, NPY-containing perikarya are mainly located in the arcuate nucleus of the hypothalamus; numerous fibers innervate the paraventricular and suprachiasmatic nuclei of the hypothalamus, as well as the paraventricular nucleus of the thalamus and the periaqueductal gray. At the electron microscope level, using the pre- and post-embedding immunoperoxidase techniques, NPY-like immunoreactivity has been observed in neuronal cell body dendrites and axonal processes. In nerve terminals of the hypothalamus, the product of the immunoreaction is associated with large dense core vesicles. In lower vertebrates, including amphibians and fish, neurons originating from the diencephalic (or telencephalic) region innervate the intermediate lobe of the pituitary where a dense network of immunoreactive fibers has been detected. At the ultrastructural level, positive endings have been observed in direct contact with pituitary melanotrophs of frog and dogfish. These anatomical data suggest that NPY can act both as a neurotransmitter (or neuromodulator) and as a hypophysiotropic neurohormone. In the rat a few NPY-containing fibers are found in the internal zone of the median eminence and high concentrations of NPY-like immunoreactivity are detected in the hypothalamo-hypophyseal portal blood, suggesting that NPY may affect anterior pituitary hormone secretion. Intrajugular injection of NPY causes a marked inhibition of LH release but does not significantly affect other pituitary hormones. Passive immunoneutralization of endogenous NPY by specific NPY antibodies induces stimulation of LH release in female rats, suggesting that NPY could affect LH secretion at the pituitary level. However, NPY has no effect on LH release from cultured pituitary cells or hemipituitaries. In addition, autoradiographic studies show that sites for 125I-labeled Bolton-Hunter NPY or 125I-labeled PYY (2 specific ligands of NPY receptors) are not present in the adenohypophysis, while moderate concentrations of these binding sites are found in the neural lobe of the pituitary. It thus appears that the inhibitory effect of NPY on LH secretion must be mediated at the hypothalamic level.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
998.
G Mayor Molina M T Villarroel Salcedo J J Armendáriz Rada J Mur Franco A Peleato Peleato M P Tornos Mas M Murtra Ferré 《Revista espa?ola de cardiología》1990,43(2):119-122
Endomyocardial fibrosis, an uncommon condition, is the most important cause of restrictive cardiomyopathy. Etiology of endomyocardial fibrosis is unknown, but evidence continues to accumulate that a close connection exists between eosinophilia and endomyocardial disease. Patients with this condition respond poorly to medical treatment, and survival is only for a few months or years when late stage heart disease is present. Surgery is nowadays recommended in these cases. A marked eosinophilia was found in a 58 years old woman that was admitted to the hospital because of a severe congestive cardiac insufficiency. Two-dimensional echocardiographic study and typical angiographic appearance suggested the presence of endomyocardial fibrosis. Endocardectomy and mitral valvular replacement were performed. 相似文献
999.
What is the role of the hevein‐like domain of fruit class I chitinases in their allergenic capacity?
A. Dìaz-Perales R. Sánchez-Monge C. Blanco M. Lombardero T. Carillo G. Salcedo 《Clinical and experimental allergy》2002,32(3):448-454
BACKGROUND: Class I chitinases are the major panallergens in fruits associated with the latex-fruit syndrome. These enzymes contain an N-terminal hevein-like domain homologous to latex hevein, and a larger catalytic domain. The role of these domains in their allergenic capacity is still controversial. OBJECTIVE: We sought to evaluate the role of both domains of class I chitinases in their IgE-binding properties, using Cas s 5, the major allergen from chestnut, as a model. METHODS: Recombinant Cas s 5 and its deleted form, lacking the hevein-like domain, designated rCat, were expressed in Pichia pastoris using the pPIC 9 vector. Both recombinant products were purified from the supernatants of transformed yeast cultures by gel-filtration and cation-exchange chromatography. The isolated proteins were characterized by N-terminal sequencing, enzymatic activity and N-glycosylation tests, anti-chitinase and specific IgE immunodetection. Immunoblot, RAST and CAP inhibition assays were also performed. RESULTS: Both purified rCas s 5 and rCat showed the expected N-terminal amino acid sequences and an enzymatic activity similar to that of their natural counterparts isolated from chestnut seeds, and were strongly recognized by anti-chitinase antibodies. In contrast, only rCas s 5, but not rCat, bound specific IgE from sera of patients suffering from the latex-fruit syndrome, and fully inhibited IgE-binding to natural Cas s 5 in immunoblot inhibition assays. Latex hevein also exerted a strong immunoblot inhibition of IgE-binding to chestnut Cas s 5. RAST and CAP inhibition using whole chestnut extract on the solid phase, rendered inhibition levels around 70-90% for rCas s 5 and 60% for rCat, in contrast to the immunoblotting results. CONCLUSIONS: Recombinant Cas s 5 behaves like natural Cas s 5 in IgE-binding assays in vitro. The hevein-like domain of allergenic class I chitinases seems to include all their main IgE-binding epitopes when tested by immunodetection and immunoblot inhibition experiments. RAST and CAP inhibition assays, on the contrary, suggest that relevant epitopes are also harboured in the catalytic domain of these allergens. 相似文献
1000.
Limb-sparing surgery for soft tissue sarcomas: wound related morbidity in patients undergoing wide local excision 总被引:6,自引:0,他引:6
When feasible, limb-sparing surgery has become an accepted form of treatment for sarcoma of the extremities. In a review of 100 consecutive cases of local excisions in patients with soft tissue sarcomas, which were performed at the National Cancer Institute, we identified factors associated with the development of wound-related morbidity. The incidence of these wound complications, which include infection, seromas, and skin loss, was 34.4%. Serious complications that necessitated rehospitalization or reoperation occurred in fewer than 10% of the patients. Preoperative factors associated with wound morbidity were patient age greater than 40 years (P2 less than 0.029) and tumor in the lower extremity (P2 less than 0.014). Treatment-related factors associated with morbidity were increased blood loss (p less than 0.01) and an increased volume (p less than 0.006) and duration (p less than 0.002) of wound drainage. The complications significantly delayed the start of adjuvant radiation therapy and lengthened the hospital stay. Measures to prevent these complications are discussed. 相似文献