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21.
The purpose of this study was to define the treatment of choice (partial laryngectomy vs radiotherapy) in the early stage of supraglottic squamous cell cancer (ESSC). One hundred and fifteen patients with ESSC were treated with either partial laryngectomy (25 patients) or with radiotherapy(90 patients) between January 1984 and December 1996. All patients had a follow-up of over ¶29 months. Radiotherapy (RT) had a local control rate of 79%, which increased to 90% with salvage surgery, and a high larynx preservation rate (83%). Partial laryngectomy (PL) offered a better initial local control rate of 84%, which increased to 88% with salvage surgery, and functional results were also good (80%). No statistically significant differences were found between RT and PL. RT was less costly, showed better suitability for treatment, produced moderate morbidity and sequelae, and local recurrence was easier to rescue. However, it is a once-only application technique. PL showed higher immediate postoperative morbidity, higher cost and lower suitability for treatment but had fewer sequelae, offered the best initial local control and is multi-applicable. No clear oncological arguments were found in our series to define whether PL or RT is the treatment of choice for ESSC. Both are effective therapies. Secondary factors such as suitability for treatment, morbidity, cost and applicability should be individually evaluated when choosing the type of treatment. As the laser endoscopic approach decreases morbidity and costs and makes the condition more suitable for treatment, it could be the treatment of choice for ESSC, in cases where local tumoral extent and larynx exposure allow radical excision. 相似文献
22.
Chromosome painting in plants: in situ hybridization with a DNA probe from a specific microdissected chromosome arm of common wheat. 总被引:6,自引:0,他引:6 下载免费PDF全文
M Vega S Abbo M Feldman A A Levy 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(25):12041-12045
We report here on the successful painting of a specific plant chromosome within its own genome. Isochromosomes for the long arm of chromosome 5 of the wheat B genome (5BL) were microdissected from first meiotic metaphase spreads of a monoisosomic 5BL line of the common wheat Triticum aestivum cv. Chinese Spring. The dissected isochromosomes were amplified by degenerate oligonucleotide-primed PCR in a single tube reaction. The amplified DNA was used as a complex probe mixture for fluorescent in situ hybridization on first meiotic metaphase spreads of lines carrying 5BL as a distinctive marker. Hybridization signals were observed, specifically, along the entire 5BL. In some of the cells, labeling was also detected in two bivalents, presumably those of the 5B "homoeologues" (partial homologues) found in common wheat (5A and 5D). The probe also revealed discrete domains in tapetal nuclei at interphase, further supporting the probe's high specificity. These data suggest that chromosome and homoeologous group-specific sequences are more abundant in 5BL than genome-specific sequences. Chromosome-painting probes, such as the one described here for 5BL, can facilitate the study of chromosome evolution in polyploid wheat. 相似文献
23.
R S Zimmerman W A Vega A G Gil G J Warheit E Apospori F Biafora 《American journal of public health》1994,84(12):1985-1987
What is the appropriate method for classifying Spanish-speaking-origin inhabitants of the United States? This paper presents relevant data from the first wave of a longitudinal study of adolescents in the greater Miami area. As expected, the broadest definition--"up to third generation" Hispanic--identified the largest proportion of the sample as Hispanic, whereas parent self-report placed the smallest proportion into the Hispanic category. When policymakers are concerned about enumerating the entire Hispanic population, a definition broader than self-identification should be used; in estimating prevalence rates, however, the use of self-identification may be adequate. 相似文献
24.
J. Vázquez J. Murcia M. López-Santamaría M. Gámez M. C. Díaz L. Hierro A. Vega L. Goldman P. Jara J. A. Tovar 《Pediatric surgery international》1994,9(3):176-179
Thrombosis of the hepatic artery (HAT) is a severe complication of liver transplantation, and most cases need regrafting. The aim of this study was to review our experience with this complication. From January 1986 through January 1992, 76 liver transplants were performed in 59 pediatric patients at the Children's Hospital La Paz, Madrid. The diagnosis of HAT was made in 12 cases (15.7%). The common patterns of clinical presentation were: fulminant liver necrosis (5), bile leak due to necrosis of the bile duct (4), and relapsing bacteremia (3). Clinical symptoms of fulminant liver necrosis started within the first 2 weeks after transplantation, with rapid deterioration and steep rises in SGOT and SGPT levels. All these patients were retransplanted on an urgent basis, but only 1 is alive 4 years later. Four patients developed bile leaks 13 to 60 days after transplantation; SGOT, SGPT, and total bilirubin were only slightly increased. Three children were retransplanted electively and are alive with a mean follow-up of 3 years. One exceptional patient had a Roux-en-Y jejunostomy and is doing well 30 months later with his original graft. The 3 remaining children had episodes of septicemia with hepatic abscess, liver infarction, and pleural effusion. Liver function tests were normal, with bilirubin levels below 2 mg/dl. All patients were retransplanted, but only 1 is alive and well 13 months later. In the present series, we found that early HAT produces fulminant clinical deterioration requiring an urgent regraft. Late HAT presenting with either infection or bile leak allows time for treatment by elective retransplantation. The best survival was obtained in the latter group.
Correspondence to: J. Vázquez 相似文献
25.
Suárez-Pérez E Oliver-Vázquez M De Andino R Vega R Conde J García M Rosario R Vélez H 《Puerto Rico health sciences journal》1999,18(4):377-386
In order to plan the health services for the elderly population, it is necessary to quantify their health status and their functional capacity. In Puerto Rico, few epidemiological studies have been conducted regarding functional capacity and chronic diseases in the elderly population. One of the difficulties to undertake these studies is the high cost and risks to move this population for clinical exams, in addition to the methodology limitation of self-report in the elderly population. This study shows the use of logistic regression to estimate the prevalence of chronic diseases and functional capacity, when the observed data are not consisted with the planed sampling scheme. Four hundred and eighty-seven elderly persons (65 yr. and over) were interviewed in the municipalities of Canóvanas, Carolina, Loíza and Trujillo Alto in Puerto Rico, using a cross-sectional design. More than half of the elderly had visual problems (IC 95%: 54.8%, 63.8%), arthritis (IC 95%: 52.7%, 61.5%) and hypertension (IC 95%: 47.3%, 56.3%). In the case of hypertension, significant differences (p < 0.05) by sex were observed, where women reported a higher prevalence than men. One of the higher prevalences in the functional capacity status was with urine accidents. More than one-third of the population is estimated to have this problem (IC 95%: 34.7%, 43.4%). One-fourth of the population had limitations with going out for shopping (IC 95%: 23.9%, 31.9%) and using public and private transportation (IC 95%: 19.5%, 26.9%). We conclude that the applied methodology was consistent with the estimation presented in the literature and statistics from the Puerto Rico Health Department. However, it is necessary to continue assessing the design and analytical methodology, in order to undertake consistent and periodic evaluations of the elderly population. 相似文献
26.
New thieno and pyrazolo[2,1]benzothiazepine derivatives with antidepressant activity 总被引:1,自引:0,他引:1
Darias V Sánchez-Mateo CC Expósito-Orta MA Albertos LM Díaz JA Vega S 《Die Pharmazie》1999,54(10):783-784
27.
O. Garcia-Suarez F. J. Naves M. E. Del Valle I. Esteban E. Bronzetti E. Vazquez J. A. Vega 《Anatomy and embryology》1996,193(6):577-583
We investigated the expression of immunoreactivity (IR) for low- (p75) and high-affinity (trk proteins) neurotrophin-receptor proteins in adult human paravertebral-sympathetic ganglion neurons. Mouse monoclonal antibodies against the pan-neurotrophin-receptor p75, and rabbit polyclonal antibodies against specific epitopes of the intracytoplasmic domain on trk neurotrophin-receptor proteins were used in fresh unfixed and formaldehyde-fixed paraffin-embedded sympathetic ganglia. All adult human paravertebral-sympathetic neurons displayed trkA neurotrophin-receptor-like protein IR, 10% express trkC neurotrophin-receptor-like protein IR, 37–44% show p75 IR, and no IR was obtained for trkB neurotrophin-receptor-like protein. The intensity of immunostaining was independent of the neuron size. Labelling of non-neuronal tissues, especially blood-vessel walls, was observed for p75, trkA and trkC neurotrophin-receptor proteins. These results indicate that overlapping exists in the expression of p75 and trk neurotrophin-receptor proteins in adult human paravertebral-sympathetic neurons, and suggest that neurotrophins might act on these neurons. 相似文献
28.
A. Isla F. Alvarez M. Gutiérrez C. Gamallo M. García-Blázquez A. Vega 《Neuroradiology》1996,38(3):211-213
Primary lymphomas of the cranial vault are rare; only six patients have been described in the literature. We report a 75-year-old woman who was admitted to our hospital after a focal seizure. CT showed a homogeneous mass which, on contrast enhancement, was similar to a meningioma. The tumour was excised and found to be a centroblastic, centrocytic non-Hodgkin's lymphoma. Treatment was completed with radiotherapy and chemotherapy. 相似文献
29.
The conduct of in vitro and in vivo drug-drug interaction studies: a Pharmaceutical Research and Manufacturers of America (PhRMA) perspective. 总被引:12,自引:0,他引:12
Thorir D Bjornsson John T Callaghan Heidi J Einolf Volker Fischer Lawrence Gan Scott Grimm John Kao S Peter King Gerald Miwa Lan Ni Gondi Kumar James McLeod R Scott Obach Stanley Roberts Amy Roe Anita Shah Fred Snikeris John T Sullivan Donald Tweedie Jose M Vega John Walsh Steven A Wrighton 《Drug metabolism and disposition》2003,31(7):815-832
Current regulatory guidances do not address specific study designs for in vitro and in vivo drug-drug interaction studies. There is a common desire by regulatory authorities and by industry sponsors to harmonize approaches, to allow for a better assessment of the significance of findings across different studies and drugs. There is also a growing consensus for the standardization of cytochrome P450 (P450) probe substrates, inhibitors and inducers and for the development of classification systems to improve the communication of risk to health care providers and to patients. While existing guidances cover mainly P450-mediated drug interactions, the importance of other mechanisms, such as transporters, has been recognized more recently, and should also be addressed. This article was prepared by the Pharmaceutical Research and Manufacturers of America (PhRMA) Drug Metabolism and Clinical Pharmacology Technical Working Groups and represents the current industry position. The intent is to define a minimal best practice for in vitro and in vivo pharmacokinetic drug-drug interaction studies targeted to development (not discovery support) and to define a data package that can be expected by regulatory agencies in compound registration dossiers. 相似文献
30.
Domínguez Domínguez M Reina Ruiz C Blasco Hernández P Espinosa Olmedo J Conde Sánchez JM Vega Toro P García Pérez M 《Actas urologicas espa?olas》2000,24(3):219-222
Contribution of a retrospective series of 16 patients with type II absorptive hypercalciuria over a total of 1.041 patients undergoing metabolic study due to relapsing renal lithiasis. Clinical history of lithiasis, biochemistry prior to treatment and instituted therapy were examined in all cases. Stones composition, radiologic appearance of lithiasis and evolution of biochemical parameters after medical treatment with a mixture of phosphates were also studied. 相似文献