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11.
R. L. Cabrini A. E. Schwint A. Mendez F. Femopase H. Lanfranchi M. E. Itoiz 《Journal of oral pathology & medicine》1992,21(6):275-279
A morphometric study of nucleolar organizer regions (NOR) was performed to analyze their distribution, volume, number and shape in the different strata of human normal oral mucosa epithelium and papilloma and in squamous cell carcinoma employing microphotographs of silver-stained paraffin sections. The different NOR-related parameters evidenced significant differences between normal mucosa, papilloma and squamous cell carcinoma. The functional polarity of normal mucosa epithelium and of papilloma is also evidenced in terms of NOR-related parameters. The discriminative value of certain NOR parameters was demonstrated. 相似文献
12.
Pernes JM; Vitoux JF; Brenoit P; Raynaud A; Parola JL; Roth JP; Angel CY; Fiessinger JN; Roncato M; Gaux JC 《Radiology》1986,158(2):481-485
Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs. 相似文献
13.
Oscar E. Mendez MD Jingzi Shang MD PhD Charles A. Jungreis MD Daniel I. Kaufer MD 《Journal of neuroimaging》2003,13(2):147-151
Two middle-aged patients presented with rapidly progressive dementia and ataxia, nonspecific electroencephalography findings, and negative cerebrospinal fluid (CSF) protein 14-3-3. Both patients underwent brain magnetic resonance imaging (MRI) scans that demonstrated abnormalities on diffusion-weighted imaging (DWI) sequences, and both were later confirmed to have Creutzfeldt-Jakob disease. (CJD) by tissue examination. Because a recent position paper from the American Academy of Neurology characterized CSF protein 14-3-3 as a gold standard for clinically diagnosing CJD, the authors reviewed studies of CJD in which DWI-MRI imaging and CSF protein 14-3-3 studies were both performed. Among 19 reported cases of CJD with DWI-MRI lesions, CSF protein 14-3-3 was negative in 6 cases and positive in 2 others. The authors' findings suggest that multifocal cortical and subcortical hyperintensities confined to gray matter regions in DWI-MRI may be a more useful noninvasive diagnostic marker for CJD than CSF protein 14-3-3. These observations provide a compelling rationale for a prospective comparative study. 相似文献
14.
Vivek N Ahya Alden M Doyle James D Mendez David A Lipson Jason D Christie Emily A Blumberg Alberto Pochettino Linda Nelson Roy D Bloom Robert M Kotloff 《The Journal of heart and lung transplantation》2005,24(7):932-935
Chronic rejection is the major hurdle to long-term survival after lung transplantation. Endobronchial infection with Pseudomonas aeruginosa is common in patients with chronic rejection and this may further contribute to deterioration of the allograft. Inhaled tobramycin is commonly used to treat P aeruginosa airways infection in patients with cystic fibrosis. The safety of inhaled tobramycin in transplant recipients, however, has not been established. We describe the first report of a lung transplant recipient who developed renal failure and vestibular injury after receiving inhaled tobramycin. We review the literature regarding the safety of inhaled tobramycin and discuss potential mechanisms that may promote systemic toxicity in transplant recipients. 相似文献
15.
16.
Diaz-Cueto L.; Barrios-de-Tomasi J.; Timossi C.; Mendez J.P.; Ulloa-Aguirre A. 《Molecular human reproduction》1996,2(9):643-650
In the present study we analysed the dynamics of serum humanchorionic gonadotrophin (HCG) charge isoform distribution throughoutnormal gestation and characterized some of the biological featuresof the several HCG glycoforms present in the circulation ofpregnant women. Blood samples were obtained from normal pregnantwomen at 1011, 1215, 2326 and 3538weeks of gestation. The sera were fractionated by preparativechromatofocusing and the separated HCG isoforms were identifiedand quantified by radioimmunoassay. The in-vitro biologicalactivity and the plasma half-life of the several circulatingHCG isoforms were determined by conventional methods. HCG isoformsbecame less acidic as pregnancy advanced. In samples taken at1011 weeks of gestation, the most acidic HCG molecules(pH <3.7) comprised >80% of total HCG recovered afterchromatofocusing; this proportion decreased to 58, 60 and 47%in samples taken from weeks 12.1 to 38.4 of gestation. Meanwhile,the relative proportion of less acidic isoforms recovered withinpH values 6.494.50 increased at the end of the firsttrimester (1215 weeks), remained constant until weeks2326 and then increased further by the end of the thirdtrimester. Less acidic isoforms had higher in-vitro biologicalpotency per immunological unit than the more acidic analogues.Regardless of the trimester of pregnancy, the plasma half-lifeof the highly acidic (elution pH <3.7) isoforms varied from84.4 to 150 min (116.3 ± 23.0; mean ± SD), whereasthe corresponding half-life of mid-acidic (pH 4.255.31)and low-acidic (pH 5.746.50) HCG isoforms ranged from31.0 to 115.3 (75.5 ± 20.6) and 15.3 to 58.3 (41.2 ±14.3) min respectively (P <0.01, highly acidic versus mid-and low-acidic analogues and mid-acidic versus least acidicisoforms). The overall data indicate that the human trophoblastis able to regulate the exact intensity, biochemical compositionand duration of the gonadotrophic stimulus secreted during thecourse of normal gestation. They also suggest that the decreaseand maintenance of low serum HCG concentrations during the secondand third trimesters of gestation may be partially caused bychanges in the carbohydrate structure of the HCG molecule charge isoforms/human chorionic gonadotrophin/pregnancy 相似文献
17.
R Mokni A Chakar F Bleiberg-Daniel JL Mahu PA Walravens P Chappuis J Navarro D Lemonnier 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(6-7):539-543
Biochemical markers of nutritional status (albumin, transthyretin, insulin-like growth factor-I and zinc) were measured in slowly growing two- to five-year-old, low-income Parisian children whose weight-for-height or height-for-age z scores (WHZ or HAZ) were between — 1 and — 2 SD of the NCHS median. The results were compared to controls who were matched for age, sex, and ethnic origin with WHZ and HAZ between — 1 and + 2 SD. Mean serum levels of transthyretin, albumin and insulin-like growth factor-I and mean plasma zinc concentrations were significantly lower in the growth-impaired children than in the controls ( p = 0.002, p = 0.006, p = 0.015, and p = 0.035, respectively). While the height-retarded children had low mean serum insulin-like growth factor-I values, the weight-retarded subjects had decreased levels of albumin, transthyretin and zinc when compared to controls. Lower mean levels of nutritional markers in healthy, slowly growing children suggest that inadequate dietary intakes of zinc, protein and/or energy may result in marginal delays in weight and height gains. 相似文献
18.
JI Elizalde ; J Clemente ; JL Marin ; J Panes ; B Aragon ; A Mas ; JM Pique ; J Teres 《Transfusion》1997,37(6):573-576
BACKGROUND: Equilibration of hemoglobin concentration after transfusion has been estimated to take about 24 hours, but some studies have shown that earlier measurements reflect steady-state values in persons who have not bled recently. This study was aimed at assessing the changes over time in hemoglobin concentration after transfusion in acutely anemic patients because of recent bleeding. STUDY DESIGN AND METHODS: Thirty-two normovolemic patients recovering from an acute bleeding episode who were no longer thought to be bleeding and who received a 2- unit red cell transfusion were studied. At baseline and 15, 30, 60, and 120 minutes and 24 hours after transfusion, hemoglobin concentration and hematocrit values were measured. RESULTS: The administration of 2 units of packed red cells elicited a 24-hour increase of 22.4 +/− 6.8 g per L in hemoglobin concentration. Hemoglobin values were not different at any of the defined posttransfusion times. Hematocrit levels experienced similar changes over time. Agreement between 15-minute and 24-hour values was excellent, as only 6 percent of patients exhibited a clinically significant difference (> 6 g/L) between the hemoglobin measurements. CONCLUSION: Hemoglobin and hematocrit values rapidly equilibrate after transfusion in normovolemic patients who are recovering from an acute bleeding episode. This fact would allow a rapid assessment of the effects of transfusion and of the recurrence of bleeding in patients remaining at risk. 相似文献
19.
Andres A; Morales JM; Praga M; Campo C; Lahera V; Garcia-Robles R; Rodicio JL; Ruilope LM 《Nephrology, dialysis, transplantation》1997,12(7):1437-1440
BACKGROUND: Cyclosporin has been shown to facilitate renal vasoconstriction
and to have an antinatriuretic effect. The existence of an interference of
cyclosporin with the vasodilating properties of endothelium mediated by
nitric oxide production could mediate these effects. On the other hand, the
infusion of the nitric oxide precursor L-arginine has been shown to induce
renal vasodilatation and to facilitate natriuresis in normal volunteers. We
have investigated the renal effects of the administration of an infusion of
L-arginine in renal transplant patients chronically treated with
cyclosporin. To facilitate the analysis of the data the effects of the
administration of a similar dose of cyclosporin on renal function during
the infusion of a vehicle were also investigated during the administration
of a vehicle of L-arginine. DESIGN: Ten male renal transplant patients,
chronically treated with cyclosporin and with a stable renal function were
studied during 2 consecutive days after the administration of the usual
morning dose of cyclosporin. The first day they received an intravenous
infusion of vehicle and the second the infusion of graded doses of
L-arginine (50, 100, 150 mg/kg/h) during 3 consecutive h. RESULTS: The
first day, after cyclosporin administration a significant fall (P <
0.01) was observed in natriuresis and kaliuresis in the absence of changes
in renal plasma flow and glomerular filtration rate. After the
administration of L-arginine significant (P < 0.01) increases of renal
plasma flow, glomerular filtration rate, and natriuresis were seen. The
increase in blood levels of cyclosporin after its administration did not
differ between days 1 and 2. CONCLUSION: These results indicate that
L-arginine facilitates renal vasodilatation and natriuresis in renal
transplant patients. Furthermore, the observed increase in sodium excretion
could indicate that L-arginine counteracts the antinatriuretic effect of
cyclosporin.
相似文献
20.