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31.
Abdullahi Idris Nasir Lozano Carmen Juárez-Fernández Guillermo Höfle Ursula Simón Carmen Rueda Silvia Martínez Angela Álvarez-Martínez Sandra Eguizábal Paula Martínez-Cámara Beatriz Zarazaga Myriam Torres Carmen 《European journal of clinical microbiology & infectious diseases》2023,42(5):569-581
European Journal of Clinical Microbiology & Infectious Diseases - This study determined the carriage rates and antimicrobial resistance (AMR) genes of enterococci from... 相似文献
32.
4-Phenyl-1-(4-phenylbutyl)piperidine(4-PPBP) is a very potent ligand for σ (Sigma) receptors. The present study was undertaken to evaluate [3H]4-PPBPas a radioligand for in vivo labeling of cerebral σ receptors. After intravenous administration of [3H]4-PPBP to mice, there is high uptake of radioactivity in the brain. The regional distribution of radioactivity in the brain 2 h after intravenous injection of [3H]4-PPBP parallels the in vitro binding of the radioligand in rat brain (pons/medulla > cerebellum ≥ prefrontal cortex ≥ parietal cortex > hypothalamus > olfactory tubercle ≥ thalamus > hippocampus > striatum). Pretreatment with haloperidol (2 mg/kg) significantly decreases the radioactivity measured in the brain 30–120 min after injection of [3H]4-PPBP. Pretreatment with unlabeled 4-PPBP or ifenprodil also significantly decreases radioactivity in the brain 2 h after injection of [3H]4-PPBP, in a dosedependent manner. The in vivo binding of [3H]4-PPBP in the brain also is significantly inhibited by SL 82.0715, BMY 14802, 1,3-di-o-tolylguanidine (DTG), and (+)-enantiomers of pentazocine, SKF 10,047, and 3-PPP, but not by the corresponding (?)-enantiomers, consistent with stereoselectivity of inhibition obtained in in vitro binding studies. In contrast, pretreatment with dizocilpine and spiperone does not inhibit in vivo binding of [3H]4-PPBP. The results indicate that [3H]4-PPBP would be a suitable radioligand for in vivo labeling of σ receptors in brain. © 1995 Wiley-Liss, Inc. 1 This article is a US Government work and, as such, is in the public domain in the United States of America . 相似文献
33.
Stefanini ML Colli C Lerner BR Lei DL Chaves SP Di Pietro MS Oliveira AA Szarfarc SC 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》1995,11(3):439-447
The authors studied a sample of students entering the first grade in the Osasco public school system in order to determine both the prevalence of anemia and nutritional status. Osasco is part of the Greater S o Paulo Metropolitan Area. Diagnosis of anemia was made through the hemoglobin concentration of blood from digital puncture. World Health Organization (WHO) levels were used to define anemia. Nutritional Status assessment. was made through weight/age and height/age indices, using Z score distribution and the National Center for Health Statistics (NCHS) reference levels. Prevalence of anemia was 51%. Prevalence levels varied according to the schools' geographic location: 56.9% in peripheral neighborhoods and 41.7% in central areas. Children with illiterate parents had a higher prevalence of this condition. Risk of anemia was higher for children who were over eight years of age when entering the first grade. Acute malnutrition was not found. Prevalence was higher than expected and points to the urgent need to establish an anemia control program for schoolchildren in this population. 相似文献
34.
Maffei HV Moreira FL Kissimoto M Chaves SM Faro SE Aleixo AM 《Jornal de pediatria》1994,70(5):280-286
In order to better understand the natural history of chronic functional constipation, a questionnaire was applied to 163 children and infants, before beginning standardized treatment. Median age (range) at start was 3 mo(0-108 mo) but age at arrival at the Pediatric Gastroenterology Unit was 53 mo(2-146 mo). In 62.4% of the cases symptoms began before or up to 3 mo after cow's milk introduction and rarely around (-/+ 6 mo) toilet training. Possible complications appeared progressively, often at preschool or school age or as the first noticeable manifestation: recurrent abdominal pain (61.1%), fecal soiling (45.4%), fecal blood (35%), enuresis (23.3%), vomiting (19%), urinary infection (17.9%), urinary retention (8.6%). Abdominal distension was rarely detected on physical examination and was usually discrete. In conclusion, children attended in Botucatu begin their constipation at an early age, frequently associated with weaning,and important complications may ensue along years. This evolution should be avoided by prevention and early treatment of constipation. 相似文献
35.
36.
The ultrastructure of parapapillary chorioretinal atrophy in eyes with secondary angle closure glaucoma 总被引:4,自引:0,他引:4
Toshiaki Kubota Ursula M. Schlötzer-Schrehardt Gottfried O. H. Naumann Toshihiko Kohno Hajime Inomata 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1996,234(6):351-358
Background: The present study was performed to investigate the ultrastructure of deep retinal layers and choroid corresponding to the parapapillary chorioretinal atrophy in eyes with secondary angle-closure glaucoma. Methods: The glaucomatous eyes included two eyes enucleated due to iris ring melanoma with high intraocular pressure and one eye with neovascular glaucoma enucleated due to ocular pain. The control eyes included one eye enucleated due to choroidal malignant melanoma with normal intraocular pressure and one eye enucleated during surgery for supramandibular carcinoma. These eyes were studied with light and electron microscopy. Results: In the region of parapapillary chorioretinal atrophy of glaucomatous eyes, the retinal pigment epithelial cells showed degenerative changes, such as loss of basal in foldings and microvilli, degenerated mitochondria, vacuolar degeneration and irregular distribution of melanin granules. The photoreceptors were decreased in number in this area of glaucomatous eyes. The lumen of the choriocapillary vessels adjacent to the optic nerve was collapsed. Conclusion: These results elucidate the fine structures of deep retina and choroid in the region of parapapillary chorioretinal atrophy of glaucomatous eyes, and suggest that the reduced choroidal perfusion might be the pathogenetic mechanism of glaucomatous parapapillary chorioretinal atrophy. 相似文献
37.
D. Chaves 《International orthopaedics》1980,3(4):253-256
Summary The classical surgical treatment of unicameral bone cysts of the humerus with curettage and bone grafting is unreliable with approximately 40% failure rate. The author describes a technique of subperiosteal diaphyseal and metaphyseal resection and replacement with a section of fibula maintained in position with an intramedullary nail and further supported by massive tibial cortical and cancellous grafting. Consistent incorporation of the graft and excellent remodelling were observed in 36 patients so treated. No complications or recurrence were reported.
Résumé Le traitement chirurgical «classique» des kystes solitaires de l'humérus par curettage et greffe osseuse ne donne pas des résultats constants, puisqu'il comporte environ 40% d'échecs. L'auteur décrit une technique de résection sous-périostée, diaphysaire et métaphysaire, avec remplacement par un fragment de péroné maintenu par enclouage centro-médullaire et complété par des greffons tibiaux cortico-spongieux. Une parfaite incorporation de la greffe et un excellent remodelage ont été obtenus dans les 36 cas traités de cette manière. Il n'y a eu ni complications, ni récidives.相似文献
38.
Ursula M. Mayer K. Sames 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1981,217(2):117-124
Zusammenfassung Mit Hilfe der beschriebenen Technik gelang es, Linsenepithelien über 40 Passagen zu züchten; zugleich fanden morphologische Alterungsveränderungen und Sauerstoffverbrauch der Zellen im Warburg-Apparat Beachtung. Vergleichbare Untersuchungen sind derzeit nicht bekannt. Morphologisch überwogen Alterationen wie Vergrößerung des Zelleibes neben bekannten Degenerationszeichen. Der Sauerstoffverbrauch von 2 l pro Stunde pro 105 Zellen zeigte sich in konstanter Höhe bis zur 39. Passage und sank dann abrupt auf etwa ein Viertel. Nachdem die Zellen ohne ersichtlichen Grund danach plötzlich starben, liegt die Folgerung nahe, daß der aerobe Stoffwechsel der Linsenepithelien unabhängig von ihrem Alter und ohne sich signifikant abzeichnenden Tagesrhythmus mit ihrem Überleben verbunden erscheint.
Herrn Prof. Dr. E. Schreck, dem damaligen Direktor der Klinik, in Dankbarkeit zum 70. Geburtstag 相似文献
Oxygen consumption and aging in longterm cultures of lens epithelia
By means of the described technique lens epithelia were cultured in 40 subcultures; at the same time, both the morphological aging processes and oxygen consumption of the cells, were observed using the Warburg respirometer. To date comparable studies are not available. Morphologically, cell enlargement took place in conjunction with signs of degeneration. Oxygen consumption of 2 l per hour per 105 cells ±0.8 remained at a constant level without any significant diurnal rhythm up to subculture 39 and then suddenly fell to about one-fourth of the initial value. As the cells died of an unknown cause, it was concluded that the aerobic metabolism of lens epithelia seemed to be linked to survival without being age related.
Herrn Prof. Dr. E. Schreck, dem damaligen Direktor der Klinik, in Dankbarkeit zum 70. Geburtstag 相似文献
39.
Diffuse cortical dysplasia, or the 'double cortex' syndrome: the clinical and epileptic spectrum in 10 patients 总被引:21,自引:0,他引:21
A Palmini F Andermann J Aicardi O Dulac F Chaves G Ponsot J M Pinard F Goutières J Livingston D Tampieri 《Neurology》1991,41(10):1656-1662
Diffuse neuronal migration disorders associated with epilepsy can now be recognized by modern neuroimaging techniques, particularly high-resolution MRI. We report 10 patients with a recently described MRI picture of continuous or generalized band heterotopia underlying the cortical mantle, giving the appearance of a "double cortex." They have epilepsy, and almost all have mental retardation. The epileptic disorder varies in nature and degree of severity. Patients may present with infantile spasms, a Lennox-Gastaut syndrome, or other forms of secondary generalized or multifocal epilepsy. Response to medical treatment is variable. Callosotomy may lead to considerable reduction of drop attacks, present in 60%. Mental retardation is usually mild or moderate, and only rarely severe. It correlates with the type of epileptic syndrome, and is greater in patients with more disorganized cortex overlying the heterotopia. Recognition of this entity by MRI is important for appropriate diagnosis of the epileptic disorder, planning of therapeutic strategy, and prognosis. 相似文献
40.
Circulating growth factor levels are associated with tumorigenesis in neurofibromatosis type 1. 总被引:2,自引:0,他引:2
George A Mashour Pablo Hernáiz Driever Melanie Hartmann Stephanie N Drissel Tingguo Zhang Bianca Scharf Ursula Felderhoff-Müser Sadatoshi Sakuma Reinhard E Friedrich Robert L Martuza Victor Felix Mautner Andreas Kurtz 《Clinical cancer research》2004,10(17):5677-5683
PURPOSE: Neurofibromatosis type 1 (NF1) is characterized by systemic development of neurofibromas. Early clinical diagnosis can be ambiguous, and genetic diagnosis can be prohibitively difficult. Dysregulation of a number of growth factors has been suggested to be a mechanism of pathogenesis. This study was performed to assess the contribution of circulating growth factors for diffuse tumorigenesis and the diagnostic value of circulating growth factor identification in serum. EXPERIMENTAL DESIGN: The growth stimulation of neurofibroma-derived cells by serum from NF1 patients was tested, and serum growth factor levels in a cohort of NF1 patients (n = 39) between the ages of 7 and 70 years were analyzed. RESULTS: Concentrations of midkine (MK) and stem cell factor, but not epidermal growth factor, were substantially increased in serum of NF1 patients when compared with healthy controls. Within the NF1 group, MK levels increased dramatically at puberty from an average of 0.79 ng/mL in patients <18 years to 1.18 ng/mL in patients >18 years old. Stem cell factor and MK concentrations above a defined threshold in serum of NF1 patients are of diagnostic benefit for 96% of patients in the cohort tested. Furthermore, serum from NF1 patients enhanced proliferation of human neurofibroma-derived primary Schwann cells and endothelial cells substantially better than normal serum. CONCLUSIONS: Enhanced circulating growth factor levels contribute to diffuse tumorigenesis in NF1 and may provide the basis for molecular diagnosis. 相似文献