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1.
Genet Mol Res ; 11(3): 2729-32, 2012 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-22782631

RESUMEN

In breeding programs, a large number of F2 individuals are required to perform the selection process properly, but often few such plants are available. In order to obtain more F2 seeds, it is necessary to multiply the F1 plants. We developed a rapid, efficient and reproducible protocol for in vitro shoot regeneration and rooting of seeds using 6-benzylaminopurine. To optimize shoot regeneration, basic medium contained Murashige and Skoog (MS) salts with or without B5 Gamborg vitamins and different concentrations of 6-benzylaminopurine (25, 50 and 75 µM) using five genotypes. We found that modified MS (B5 vitamins + 25 µM 6-benzylaminopurine) is suitable for in vitro shoot regeneration of pea. Thirty-eight hybrid combinations were transferred onto selected medium to produce shoots that were used for root induction on MS medium supplemented with α-naphthalene-acetic acid. Elongated shoots were developed from all hybrid genotypes. This procedure can be used in pea breeding programs and will allow working with a large number of plants even when the F1 plants produce few seeds.


Asunto(s)
Cruzamiento/métodos , Cruzamientos Genéticos , Pisum sativum/crecimiento & desarrollo , Hibridación Genética , Filogenia , Brotes de la Planta/crecimiento & desarrollo , Brotes de la Planta/fisiología , Regeneración
2.
Genet Mol Res ; 10(4): 3403-10, 2011 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-22057996

RESUMEN

We characterized 13 accessions of dry peas of different origins from various growing regions in Argentina, based on three replications of 20 plants cultivated in 2009 and 2010 in a greenhouse, with the objective of selecting those with favorable characteristics for use in breeding programs. Significant differences were found for length and width of stipule and pod, length of the internodes and leaflets, plant height, total number of nodes, number of nodes at the first pod, number of days to flowering and to harvest, number of pods and seeds per pod, 100-seed weight and grain diameter, demonstrating a high degree of genetic variability. Phenotypic correlation analysis demonstrated that large pods produced more seeds per pod, but the seed weight decreased. Plants with smaller number of nodes in the first pod were more productive. Estimates of genotypic correlation coefficients indicated a strong inherent association among the different traits. Clustering methods grouped the accessions into five clusters. Cluster 5 included two accessions and showed the highest values for length and width of stipules (4.9 and 4.5 cm, respectively), length of leaflets (7.43 cm) and days to flowering (122.6), while cluster 3, with one accession, and cluster 4, with two accessions, showed the highest values for number of seeds per pod (3.78 and 4.39), number of pods per plant (5.33 and 5.70), length of pods (5.54 and 5.72 cm), and width of pods (1.21 and 1.20 cm, respectively). We conclude that accessions in clusters 3 and 4 would be useful for crosses with other cultivars in pea breeding programs.


Asunto(s)
Cruzamiento , Ecotipo , Variación Genética , Pisum sativum/anatomía & histología , Pisum sativum/genética , Argentina , Análisis por Conglomerados , Genotipo , Fenotipo , Filogenia , Análisis de Componente Principal , Carácter Cuantitativo Heredable
3.
Cochrane Database Syst Rev ; (1): CD003069, 2008 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-18254015

RESUMEN

BACKGROUND: It is important to institute an effective supportive therapy to maintain or recover soft tissue health around dental implants. Different maintenance regimens have been suggested, however it is unclear which are the most effective. OBJECTIVES: To test the null hypotheses of no difference between different interventions (1) for maintaining healthy peri-implant soft tissues, and (2) for recovering soft tissue health, against the alternative hypothesis of a difference. SEARCH STRATEGY: We searched the Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE. Handsearching included several dental journals. We checked the bibliographies of the identified randomised controlled trials (RCTs) and relevant review articles for studies outside the handsearched journals. We wrote to authors of all identified RCTs, to more than 55 oral implant manufacturers and to an internet discussion group to find unpublished or ongoing RCTs. No language restrictions were applied. The last electronic search was conducted on 13 June 2007. SELECTION CRITERIA: All randomised controlled trials comparing agents or interventions for maintaining or recovering healthy tissues around dental implants. DATA COLLECTION AND ANALYSIS: Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted in duplicate and independently by two review authors. Results were expressed as random-effects models using standardised mean differences for continuous data and risk ratios for dichotomous data with 95% confidence intervals. MAIN RESULTS: Eighteen RCTs were identified. Nine of these trials, which reported results from a total of 238 patients, were included. Follow ups ranged between 6 weeks and 1 year. No meta-analysis could be made since every RCT tested different interventions. Listerine mouthwash showed a reduction of 54% in plaque and 34% in marginal bleeding compared with a placebo. Two trials evaluated the efficacy of powered and sonic toothbrushes compared to manual toothbrushing and showed no statistically significant differences, though more patients liked the sonic brush. No statistical differences were found between brushing with a hyaluronic or a chlorhexidine gel, between cleaning with an etching gel or manually, between injecting a chlorhexidine or a physiologic solution inside the implant's inner part and between submucosal minocycline and a chlorhexidine gel. When an amine fluoride/stannous fluoride (AmF/SnF(2)) mouthrinse was compared with a chlorhexidine one, no statistically significant differences were found for implant failures and staining index while patients preferred and had less taste change with the AmF/SnF(2) mouthrinse. Self administered subgingival chlorhexidine irrigation resulted in statistically significantly lower plaque and marginal bleeding than a chlorhexidine mouthwash, however the mouthwash was given at a suboptimal dosage. AUTHORS' CONCLUSIONS: There was only little reliable evidence for which are the most effective interventions for maintaining or recovering health of peri-implant soft tissues. The included RCTs had short follow-up periods and few subjects. There was not any reliable evidence for the most effective regimens for long term maintenance. This should not be interpreted as current maintenance regimens are ineffective. There was weak evidence that Listerine mouthwash, used twice a day for 30 seconds, as an adjunct to routine oral hygiene, is effective in reducing plaque and marginal bleeding around implants. More RCTs should be conducted in this area. In particular, there is a definite need for trials powered to find possible differences, using primary outcome measures and with much longer follow up. Such trials should be reported according to the CONSORT guidelines (http://www.consort-statement.org/).


Asunto(s)
Implantes Dentales , Fracaso de la Restauración Dental , Enfermedades de las Encías/terapia , Pérdida de Diente/rehabilitación , Adulto , Enfermedades de las Encías/prevención & control , Humanos , Higiene Bucal/instrumentación , Higiene Bucal/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto
4.
Cochrane Database Syst Rev ; (4): CD005968, 2006 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-17054267

RESUMEN

BACKGROUND: Dental implants can be placed in fresh sockets just after tooth extraction. These are called 'immediate' implants. 'Immediate-delayed' implants are those implants inserted after weeks up to about a couple of months to allow for soft tissue healing. 'Delayed' implants are those placed thereafter in partially or completely healed bone. The advantages of immediate implants are that treatment time can be shortened and that bone height might be maintained thus possibly improving the aesthetic results. The potential disadvantages are an increased risk of infection and failures of the immediately placed implants. OBJECTIVES: To evaluate success, function, complications and patient satisfaction between 'immediate', 'immediate-delayed' and 'delayed' implants. SEARCH STRATEGY: The Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE were searched. Several dental journals were handsearched. The bibliographies of review articles were checked, and personal references were searched. More than 55 implant manufacturing companies were also contacted. Last electronic search was conducted on 7 August 2006. SELECTION CRITERIA: Randomised controlled trials (RCTs) and preference RCT evaluating immediate, immediate-delayed, and delayed implants, reporting the outcome of the interventions to at least 1 year after functional loading. DATA COLLECTION AND ANALYSIS: Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted independently and in duplicate. Authors were contacted for any missing information. Results were expressed as random-effects models using mean differences for continuous outcomes and risk ratios for dichotomous outcomes with 95% confidence intervals (CIs). The statistical unit of the analysis was the patient. MAIN RESULTS: Two RCTs were included. One RCT compared immediate implants placed in periapical infected sites versus delayed implants in 50 patients and after 1 year found no statistically significant differences. The second RCT compared immediate-delayed versus immediate implants in 46 patients. After 1 year and a half there were no statistically significant differences for prosthesis and implant failures, complications, aesthetics assessed by the patient and the papilla height assessed by the dentist. However, patients in the delayed group perceiving the period between tooth extraction and insertion of the crown significantly longer than patients in the immediate-delayed group, mean difference of VAS -20.30 (95% CI -33.36 to -7.24). There was also statistically significantly higher patient satisfaction in the immediate-delayed group, mean difference (VAS) -6.51 (95% CI -12.63 to -0.39). An independent blinded assessor judged the level of the perimplant marginal mucosa in relation to that of the adjacent teeth as more appropriate in the immediate-delayed group, with risk ratio (RR) 1.68 (95% CI 1.04 to 2.72). AUTHORS' CONCLUSIONS: Despite that the evidence is derived from only two RCTs with a limited number of patients, it is possible to suggest that immediate implants and immediate-delayed implants may offer some advantages over conventional implants in healed sites in terms of patient satisfaction and aesthetics possibly by preserving alveolar bone. Immediate implants can work and are able to shorten treatment periods, however properly designed RCTs are still needed to fully evaluate the potential advantages and risks of this treatment modality since more complications and failures may occur.


Asunto(s)
Implantación Dental Endoósea/métodos , Implantes Dentales , Extracción Dental , Implantes Dentales/psicología , Humanos , Satisfacción del Paciente , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Tiempo
5.
BAG, J. basic appl. genet. (Online) ; 32(2): 15-23, dic. 2021. graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1355727

RESUMEN

RESUMEN En 2005 se inició un programa de mejoramiento de arveja para aumentar la producción en cantidad y calidad en la Facultad de Ciencias Agrarias (FCA), Universidad Nacional de Rosario (UNR). Los primeros pasos fueron reunir una colección activa de germoplasma de todo el mundo y analizar la variabilidad genética a través de rasgos morfo-agronómicos y moleculares. En 2014, el Instituto Nacional de Tecnología Agropecuaria (INTA) y la FCAUNR unieron esfuerzos para promover el desarrollo local de genotipos de arveja adaptados a la región. Este programa, utilizando metodologías convencionales, ha obtenido hasta el momento una nueva variedad comercial (Primogénita FCA-INTA) de color de cotiledón verde, semi-áfila, con alta adaptación a las condiciones agroecológicas locales y alto potencial de rendimiento. El mejoramiento genético, sin embargo, es un proceso lento. El desarrollo de nuevas variedades requiere una década o más utilizando metodologías tradicionales, por lo que se propusieron diferentes alternativas para la reducción de este período. Los haploides duplicados y el cultivo in vitro han sido algunas de las metodologías desarrolladas, sin embargo, en legumbres no se han podido implementar de manera eficiente en los programas de mejoramiento. En este contexto, Speed Breeding surge como una tecnología que permite incrementar la eficiencia de los programas, reduciendo los costos y el trabajo requerido.


ABSTRACT A pea breeding program to increase production in quantity and quality was started in 2005 in the College of Agrarian Sciences (FCA), National University of Rosario (UNR). The first steps were to gather an active collection of germplasm from around the world and to analyze genetic variability through morpho-agronomic and molecular traits in order to set objectives. In 2014, the National Institute of Agropecuarian Technology (INTA) and the FCAUNR, joined forces to unite inter-institutional efforts for promoting the local development of pea genotypes adapted to the region. This program, using conventional methodologies, has so far obtained a new commercial line (Primogénita FCA-INTA) of green cotyledons, semileafless, with high adaptation to local agro ecological conditions and high yield potential. Breeding, nevertheless, is a slow process. Developing new pea varieties usually takes a decade or more when using traditional methodologies; thus, different alternatives were proposed for the reduction of this period. Doubled haploids and in vitro culture have been some of the methodologies developed; in pulses, however, they have not been efficiently implemented in breeding programs. In this context, Speed Breeding emerges as a technology that allows increasing the efficiency of the programs, while reducing costs and the required labor.

6.
BAG, J. basic appl. genet. (Online) ; 32(2): 25-31, dic. 2021. graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1355728

RESUMEN

RESUMEN El mejoramiento convencional puede ser complementado mediante diferentes estrategias que incrementen la eficiencia de las metodologías y la tasa actual de aumento de los rendimientos a fin de satisfacer la demanda. El uso de marcadores moleculares con el objetivo de desarrollar mapas de ligamiento de la especie, el uso de Blup (Best Linear Unbiased Prediction) para una selección eficiente de progenitores a hibridar, el uso del cultivo in vitro para incrementar artificialmente el número de plantas F1 o el uso de fenotipificación digital para una eficiente caracterización digital que puede realizarse durante la regeneración periódica y rutinaria de accesiones en colecciones de germoplasma.


ABSTRACT Conventional breeding can be complemented by different strategies that increase the efficiency of the methodologies and the current rate of increase in yields in order to meet demand. The use of molecular markers with the aim of developing linkage maps of the species, the use of Blup (Best Linear Unbiased Prediction) for an efficient selection of progenitors to hybridize, the use of in vitro culture to artificially increase the number of F1 plants or the use of digital phenotyping for efficient digital characterization that can be performed during the periodic and routine regeneration of accessions in germplasm collections.

7.
BAG, J. basic appl. genet. (Online) ; 32(2): 33-40, dic. 2021. graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1355729

RESUMEN

RESUMEN La lenteja (Lens culinaris Medik.) es una especie diploide autógama (2n=2x=14) perteneciente a la familia Fabaceae. Es uno de los cultivos más antiguos que se conocen, con 8.000 a 9.000 años de historia, y se encuentra entre los primeros domesticados en Medio Oriente. Las semillas tienen un alto valor nutricional. Este cultivo es un interesante sustituto del trigo en las rotaciones de cereales, pero su importancia es baja debido a la falta de buenas variedades con adaptación local. Uno de los principales problemas que enfrentan los mejoradores en nuestro país es la estrecha base genética del germoplasma cultivado y su bajo potencial de rendimiento. En 2004 se inició un programa de mejoramiento de lentejas para desarrollar nuevas variedades con adaptación a las condiciones predominantes en las áreas de cultivo de Argentina. El germoplasma se obtuvo del ICARDA (Centro Internacional de Investigación Agrícola en las Zonas Áridas) y de productores locales. Se utilizan métodos convencionales de mejoramiento basados en la hibridación y selección. Se han obtenido dos nuevas variedades, una del tipo macrosperma (Boyerito FCA) y la otra del tipo microsperma (Tacuarita FCA) mediante la aplicación de selección masal en poblaciones F2 provenientes de la hibridación de materiales seleccionados. Este programa complementa los métodos de mejora tradicional con técnicas biotecnológicas como la transgénesis, el uso de marcadores moleculares, el cultivo de embriones in vitro combinado con el método SSD para acortar el ciclo generacional, y el fenotipado digital.


ABSTRACT Lentil (Lens culinaris Medik.) is a self-pollinating diploid (2n=2x=14) species belonging to the Fabaceae family. It is one of the oldest crops known, with 8,000 to 9,000 years of history and it is among the earliest domesticates from the Near East Fertile Crescent. The seeds have high nutritional value. This crop is an interesting substitute to wheat in cereal rotations but its importance is low due to a lack of suitable varieties with local adaptation. Some of the major problems that Argentinian lentil breeders face are the narrow genetic base of the current cultivated germplasm and its low yield potential. A lentil breeding program was initiated in 2004 to develop new varieties with adaptation to prevalent conditions in growing areas of Argentina. Germplasm was obtained from ICARDA (International Center for Agricultural Research in the Dry Areas) and local producers. Conventional breeding methods using hybridization and selection are being carried out to develop improved varieties, broad the genetic base, and isolate superior recombinant inbred lines. Two new varieties have been obtained, one of the macrosperm type (Boyerito FCA) and the other of the microsperm type (Tacuarita FCA) through the application of mass selection in F2 populations from the cross of selected materials. This program complements traditional breeding methods with biotechnological techniques such as transgenesis, use of molecular markers, in vitro embryo culture combined with the SSD method to shorten the breeding time, and digital phenotyping.

8.
Fertil Steril ; 75(3): 519-24, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11239535

RESUMEN

OBJECTIVE: To study the effect of endogenous luteinizing hormone (LH) concentration on fertilization, pregnancy, and early pregnancy loss rates. DESIGN: Retrospective cohort study. SETTING: Tertiary-care university center. PATIENT(S): One hundred sixty-six normogonadotropic patients undergoing IVF. INTERVENTION(S): Luteal phase pituitary down-regulation and recombinant FSH (Gonal-F) were used for ovarian stimulation. The mean of 4-5 serum LH concentrations, from stimulation days 5-12, was computed for analysis. MAIN OUTCOME MEASURE(S): Fertilization, pregnancy, and early pregnancy loss rates according to periovulatory levels of LH. RESULT(S): Data were analyzed by stratifying patients according to a mean periovulatory LH value of 3 mIU/mL. After controlling for confounding variables with logistic regression, results showed that the fertilization rate was significantly lower in patients with a periovulatory LH <3 mIU/mL versus > or = 3 mIU/mL (52% and 58%, respectively; P=.03). Pregnancy rates and spontaneous abortion rates were similar in both groups. There were seven biochemical pregnancies, all in patients with an LH <3 mIU/mL (P=.07). CONCLUSION(S): Low endogenous LH concentrations (<3 mIU/mL) in the late follicular phase of an IVF cycle are associated with significantly lower fertilization rates and a trend toward higher biochemical pregnancy rates. It may be of clinical benefit, when exclusively using r-hFSH in ART cycles, to add LH in the late follicular phase or to further reduce the dose of GnRH agonist.


Asunto(s)
Fertilización In Vitro , Hormona Luteinizante/sangre , Ovulación , Aborto Espontáneo/epidemiología , Adulto , Gonadotropina Coriónica/administración & dosificación , Estudios de Cohortes , Transferencia de Embrión , Estradiol/sangre , Femenino , Hormona Folículo Estimulante/administración & dosificación , Hormona Folículo Estimulante/uso terapéutico , Hormona Folículo Estimulante Humana , Fase Folicular , Humanos , Modelos Logísticos , Inducción de la Ovulación , Embarazo , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/uso terapéutico , Estudios Retrospectivos , Inyecciones de Esperma Intracitoplasmáticas
9.
J Reprod Med ; 45(6): 511-4, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10900589

RESUMEN

BACKGROUND: Failure of oocyte retrieval during in vitro fertilization (IVF) is considered "empty follicle syndrome." Many theories have been postulated, some related to an underlying ovulatory disorder or premature oocyte atresia. As illustrated in this case and in a review of empty follicle syndrome at our institution, often it is related to improper administration of human chorionic gonadotropin (hCG). CASE: A 40-year-old woman underwent IVF for a 10-year history of unexplained secondary infertility. Two ultrasound-guided oocyte retrievals were performed 34 hours apart due to improper hCG administration prior to the first procedure. The number of oocytes successfully aspirated at the second retrieval, fertilization rate and pregnancy outcome were analyzed. Successful retrieval of 16 oocytes, all mature and fertilized, occurred subsequent to the second oocyte retrieval. No pregnancy was established with the fresh cycle. CONCLUSION: This case report supports the premise that an IVF cycle in which improper hCG administration occurs can be salvaged. After partial follicular aspiration, no ovulation or luteinization of the remaining follicles occurred because of continued suppression by the gonadotropin releasing hormone analog. It is critical to consider the possibility of improper hCG administration when facing failure of oocyte retrieval. The procedure should be terminated and hCG readministered, and a second retrieval should be performed 34 hours later.


Asunto(s)
Gonadotropina Coriónica/administración & dosificación , Fertilización In Vitro , Infertilidad Femenina/terapia , Folículo Ovárico/cirugía , Adulto , Esquema de Medicación , Femenino , Fertilización In Vitro/métodos , Humanos , Oocitos/fisiología , Succión
10.
Am J Obstet Gynecol ; 183(5): 1180-3, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11084563

RESUMEN

OBJECTIVE: The aim of this study was to determine whether a short interpregnancy interval is associated with uterine scar failure in laboring patients with previous low transverse cesarean delivery. STUDY DESIGN: This was a case-control study of uterine scar failures among laboring patients with previous low transverse cesarean delivery. Control patients underwent abdominal delivery during labor after failure of an attempted vaginal birth after cesarean delivery in the same month as case patients. RESULTS: An interpregnancy interval of <6 months was significantly more prevalent among case patients with uterine scar failure (P =.02). Mean interpregnancy interval was less in all cases of uterine scar failure (P = .06). CONCLUSIONS: Interpregnancy interval was inversely associated with likelihood of uterine scar failure during subsequent labor.


Asunto(s)
Intervalo entre Nacimientos , Cicatriz/fisiopatología , Complicaciones del Trabajo de Parto/etiología , Enfermedades Uterinas/fisiopatología , Rotura Uterina/etiología , Parto Vaginal Después de Cesárea/efectos adversos , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Funciones de Verosimilitud , Embarazo
11.
Md Med J ; 46(9): 467-70, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9327647

RESUMEN

Postmortem cesarean sections are rare events, but modern technology is forcing society to explore the definition of viability and the legal rights of both mother and fetus that ultimately will affect the frequency and use of this rare operation. Since the Human Immunodeficiency Virus (HIV) prevalence rate and the number of critically ill obstetrical patients with Acquired Immunodeficiency Syndrome (AIDS) continues to rise, it is reasonable to assume more patients and physicians may be confronted by issues concerning fetal and maternal rights and other considerations in perimortem delivery. A 33-year-old woman, at 27 weeks' gestation, with fulminant AIDS was admitted to the intensive care unit (ICU) in respiratory distress. As her condition deteriorated the complex problem of caring for both mother and fetus emerged. A patient advisory panel explored the issues with the patient, her family, and her health care team. Eventually a peri/postmortem cesarean section was performed on the mother when she suffered an acute fatal cardiorespiratory arrest. With the prevalence of AIDS increasing and with most women not being tested prior to pregnancy, many obstetricians will be confronted with new medical and legal challenges. Establishing comprehensive medical management for the critically ill obstetrical patient and understanding the legal rights of both patients (mother and fetus) will help avoid conflicts and potentially improve survival.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/complicaciones , Cesárea , Ética Médica , Complicaciones Infecciosas del Embarazo , Resultado del Embarazo , Adulto , Defensa del Niño/legislación & jurisprudencia , Resultado Fatal , Femenino , Paro Cardíaco , Humanos , Recién Nacido , Defensa del Paciente/legislación & jurisprudencia , Embarazo
12.
Hum Reprod ; 17(1): 118-23, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11756373

RESUMEN

BACKGROUND: A cycle day 3 FSH concentration is a popular screening tool for predicting success in achieving pregnancy after IVF. Difficulties interpreting this test have resulted from lack of consensus in defining an elevated FSH concentration, a change in the assays, and lack of controlling for factors which may confound the association between FSH concentration and pregnancy. METHODS: Assessment was made of the ability of a moderately elevated (10-11.4 mIU/ml, World Health Organization 2nd International Standard (IRP 78/549) and elevated FSH (>11.4 mIU/ml, conversion factor to SI units, 1.00) in predicting ability to achieve pregnancy through IVF and embryo transfer, both independently, and after controlling for confounding variables such as age, diagnosis, and response to gonadotrophins. RESULTS: A total of 293 IVF cycles were retrospectively reviewed. An FSH (>11.4) was strongly associated with inability to achieve pregnancy after IVF both independently (P < 0.01) and after multivariate analysis (P < 0.01), and had a strong predictive value (100%). A moderately elevated FSH (10-11.4) was not statistically associated with pregnancy outcome either independently or after multivariate analysis, and had a low predictive value (71%). CONCLUSIONS: Much of the predictive value of an elevated FSH is confounded by poor response to gonadotrophin stimulation, which may be overcome in younger women.


Asunto(s)
Factores de Edad , Fertilización In Vitro , Hormona Folículo Estimulante/sangre , Resultado del Tratamiento , Adulto , Análisis de Varianza , Gonadotropina Coriónica/sangre , Femenino , Humanos , Embarazo , Estudios Retrospectivos , Sensibilidad y Especificidad
13.
J Neurobiol ; 23(8): 1006-20, 1992 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1460461

RESUMEN

Adult male zebra finches underwent unilateral denervation of the syrinx or unilateral lesion of the forebrain nucleus HVC known to be important for song control. Disruptive effects on song were greater after right-side than after left-side operations. After denervation of the right half of the syrinx, the fundamental frequencies of all syllables within a song converged on a value near 500 Hz, and nearly all syllables were altered in type. In contrast, the syllables produced after denervation of the left side of the syrinx largely maintained their preoperative frequencies, and fewer syllables changed in type. Unlike nerve sections, HVC lesions did not result in strikingly lateralized effects on syllable phonology; however, HVC lesions did affect the temporal patterning of a bird's song, whereas nerve sections did not, and changes in temporal patterning were more marked after right than after left HVC lesions. Right-side dominance for zebra finch song control is the reverse of that described in other songbird species with lateral asymmetry for vocal communication. We suggest that the need for a dominant side is more important than the side of dominance.


Asunto(s)
Aves/fisiología , Encéfalo/fisiología , Lateralidad Funcional/fisiología , Vocalización Animal/fisiología , Anestesia , Animales , Encéfalo/anatomía & histología , Desnervación , Masculino , Tráquea/fisiología
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