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1.
Tijdschr Psychiatr ; 61(3): 159-163, 2019.
Artículo en Holandés | MEDLINE | ID: mdl-30896025

RESUMEN

BACKGROUND: The subject of psychiatry is not easy to define and is characterised by considerable complexity of dysfunctional human behaviour. What does this mean for the training of psychiatrists? Is further differentiation with a strong specialisation from the start of the training process the only option to develop the discipline?
AIM: To formulate a strategic direction for the future training of psychiatrists in the Netherlands and Belgium.
METHOD: Personal reflection by two senior psychiatrists from the Netherlands and Belgium.
RESULTS: The profile of the psychiatrist of the future is that of a multi-specialist. It is desirable to keep the training programme broad and to develop sufficient competencies for young colleagues to enjoy throughout their careers: in addition to the clinical competencies in diagnostics and treatment, it concerns cooperation, communication, leadership (organisation), and professionalism. Psychotherapeutic skills are essential. Specialisation after the formal education is almost inevitable. Of the current focus areas (geriatric psychiatry, child and adolescent psychiatry and adult psychiatry), especially adult psychiatry should be further differentiated. The professional associations should facilitate the transfer from one sub-area to another sub-area without extensive administrative work. The enthusiasm of medical students for psychiatry should be actively stimulated, based on a new professional profile.
CONCLUSION: Throughout the entire program (4 years in the Netherlands, 5 years in Belgium) learning general competencies (truncus communis) must be advocated. These competencies must form the basis for a deepening or specialisation after the training. This should ensure that psychiatrists can move relatively smoothly from one sub-area to another. The psychiatrist as a multi-specialist.


Asunto(s)
Competencia Clínica , Psiquiatría/educación , Psiquiatría/normas , Especialización , Bélgica , Humanos , Países Bajos
2.
Tijdschr Psychiatr ; 61(3): 217-223, 2019.
Artículo en Holandés | MEDLINE | ID: mdl-30896036

RESUMEN

BACKGROUND: The training curriculum of the psychiatrist needs to be reviewed. To determine the model of the future psychiatrist, the question of how the future psychiatry will look needs to be answered first.
AIM: Assessment of relevant developments in psychiatry and the organisation of psychiatric care with the aim to propose a profile of the future psychiatrist.
METHOD: The recent history of psychiatry as a starting point for a vision of the future.
RESULTS: 1. Psychiatry must use an integrative anthropological theory, in order to be able to understand psychopathology in its essence. 2. Content-driven moral leadership is necessary to prevent psychiatry being tempted by hypes. 3. The tacit social contract between the medical profession and society is under pressure; both parties distrust each other and psychiatrists must regain trust and renew the contract. 4. Psychiatric care must remain affordable, which means a review of the current organisation of care; psychiatry will become network psychiatry. 5. Psychiatrists will work in a network of care providers and the patient will be in control. The psychiatrist will have a flexible role, ranging from managerial to supportive and advisory. Keeping psychotherapeutic skills up-to-date is an essential requirement. 6. Future training should focus on the sustainable employability of the psychiatrist as a human being, on knowledge of history of psychiatry and its socio-economic context, and policy and engagement; and on the skill of conceptual thinking (philosophy).
CONCLUSION: The profession of psychiatry needs a new job profile. The process of development and elaboration should contain the following core elements: broad education, conceptual skills, sensitivity for activism, social involvement, and expertise in treatment of patients with complex problems in diverse settings.


Asunto(s)
Curriculum , Psiquiatría/tendencias , Predicción , Humanos , Países Bajos
3.
BMC Womens Health ; 17(1): 47, 2017 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-28732531

RESUMEN

BACKGROUND: Success rates of assisted reproductive techniques (ART) are approximately 30%, with the most important limiting factor being embryo implantation. Mechanical endometrial injury, also called 'scratching', has been proposed to positively affect the chance of implantation after embryo transfer, but the currently available evidence is not yet conclusive. The primary aim of this study is to determine the effect of endometrial scratching prior to a second fresh in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycle on live birth rates in women with a failed first IVF/ICSI cycle. METHOD: Multicenter randomized controlled trial in Dutch academic and non-academic hospitals. A total of 900 women will be included of whom half will undergo an endometrial scratch in the luteal phase of the cycle prior to controlled ovarian hyperstimulation using an endometrial biopsy catheter. The primary endpoint is the live birth rate after the 2nd fresh IVF/ICSI cycle. Secondary endpoints are costs, cumulative live birth rate (after the full 2nd IVF/ICSI cycle and over 12 months of follow-up); clinical and ongoing pregnancy rate; multiple pregnancy rate; miscarriage rate and endometrial tissue parameters associated with implantation failure. DISCUSSION: Multiple studies have been performed to investigate the effect of endometrial scratching on live birth rates in women undergoing IVF/ICSI cycles. Due to heterogeneity in both the method and population being scratched, it remains unclear which group of women will benefit from the procedure. The SCRaTCH trial proposed here aims to investigate the effect of endometrial scratching prior to controlled ovarian hyperstimulation in a large group of women undergoing a second IVF/ICSI cycle. TRIAL REGISTRATION: NTR 5342 , registered July 31st, 2015. PROTOCOL VERSION: Version 4.10, January 4th, 2017.


Asunto(s)
Transferencia de Embrión/métodos , Endometrio/cirugía , Fertilización In Vitro/métodos , Nacimiento Vivo , Inyecciones de Esperma Intracitoplasmáticas/métodos , Adolescente , Adulto , Tasa de Natalidad , Implantación del Embrión , Endometrio/lesiones , Femenino , Humanos , Países Bajos , Embarazo , Índice de Embarazo , Resultado del Tratamiento , Adulto Joven
4.
Tijdschr Psychiatr ; 59(11): 720-725, 2017.
Artículo en Holandés | MEDLINE | ID: mdl-29143957

RESUMEN

BACKGROUND: A relatively small number of psychiatrists in the Netherlands have a non-Dutch origin. We suspect that resident psychiatrists who do not have Dutch as their first language are less likely than native Dutch speakers to complete the psychiatry residency training programmes.
AIM: To find out how often and for what reasons resident psychiatrists do not complete the psychiatry residency training programmes.
METHOD: All course coordinators in the Netherlands were asked to participate in a survey to provide information about the residents who had started but had abandoned the psychiatry residency training programmes between the years 2008 and 2015. They were also asked about factors that had influenced residents to abandon the course.
RESULTS: We were able to obtain data on 37% of the trainees. The data revealed that the number of non-native resident psychiatrists who failed to complete the training course was almost four times higher than the number of native trainee psychiatrists who dropped out before the end of the course. According to the coordinators, possible reasons for this discrepancy are lack of proficiency in Dutch, communication problems and cultural differences.
CONCLUSION: The results of our survey could possibly be used to adjust the training programmes.


Asunto(s)
Etnicidad/estadística & datos numéricos , Internado y Residencia , Psiquiatría/educación , Femenino , Humanos , Masculino , Países Bajos
6.
Pancreatology ; 15(3): 203-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25891791

RESUMEN

OBJECTIVE: To assess the efficacy of antioxidants in acute (AP) pancreatitis. METHODS: We searched PubMed, Embase and the Cochrane library for all randomized controlled trials (RCT) involving administration of antioxidants in the therapy of AP until February 2012. AP studies were pooled to analyze the effect of antioxidants on hospital stay, mortality, and complications. Subgroup analyses were performed on the use of the antioxidant glutamine. RESULTS: In total, eleven RCTs were included. Among patients with AP, antioxidant therapy resulted in a borderline significant reduction in hospital stay (mean difference -1.74; 95%CI -3.56 to 0.08), a significant decrease in complications (RR 0.66; 95%CI 0.46-0.95) and a non-significant decrease in mortality rate (RR 0.66; 95%CI 0.30-1.46). Subgroup analyses showed that glutamine significantly reduced complications (RR 0.51; 95%CI 0.34-0.78) and mortality rate (RR 0.33; 95%CI 0.13-0.85). CONCLUSION: The present meta-analysis shows a possible benefit of glutamine supplementation in patients with acute pancreatitis. However, large randomized trials are needed to confirm these observations.


Asunto(s)
Antioxidantes/uso terapéutico , Glutamina/uso terapéutico , Pancreatitis/tratamiento farmacológico , Enfermedad Aguda , Humanos , Tiempo de Internación , Pancreatitis/complicaciones , Pancreatitis/mortalidad , Resultado del Tratamiento
7.
Andrologia ; 47(8): 847-60, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25352353

RESUMEN

Males with abnormal karyotypes and subgroups of fertile and infertile males with normal karyotypes may be at risk of producing unbalanced or aneuploid spermatozoa. Biological, clinical, environmental and other factors may also cause additional sperm aneuploidy. However, increased risk of sperm aneuploidy is directly related to chromosomally abnormal embryo production and hence to poor reproductive potential. This systemic literature review focuses on the identification of these males because this is an essential step in the context of assisted reproduction. This research may allow for a more personalised and, hence, more accurate estimation of the risk involved in each case, which in turn will aid genetic counselling for affected couples and help with informed decision-making.


Asunto(s)
Aneuploidia , Infertilidad Masculina/etiología , Espermatozoides/anomalías , Humanos , Infertilidad Masculina/genética , Cariotipo , Masculino , Factores de Riesgo
8.
Tijdschr Psychiatr ; 55(3): 165-75, 2013.
Artículo en Holandés | MEDLINE | ID: mdl-23512628

RESUMEN

BACKGROUND: Outpatient dialectical behaviour therapy (DBT) reduces severe suicidal and self-injurious behaviour in patients with borderline personality disorder. The Jelgersma center for personality disorders has developed an intensive inpatient dbt programme that lasts for 14 weeks and is designed to achieve a faster reduction in these borderline symptoms. AIM: To examine the effect of the Jelgersma programme by means of a pilot study in order to prepare a randomised clinical trial in which a short intensive course of DBT will be compared with standard outpatient DBT. METHOD: We compared the starting data and the final data for 39 female patients with borderline problems (DBT). We participated in 3½-month-long inpatient DBT programme. The collected data referred to (para)suicidal behaviour, drop-out, severity of borderline problems and the quality of life. RESULTS: The severity of borderline problems, particularly in the field of interpersonal problems, was significantly reduced. There was no significant reduction in (para) suicidal behaviours. The drop-out percentage was higher than in comparable studies. CONCLUSION: Short-term inpatient DBT had a positive effect on borderline problems. (Para)suicidal behaviour, however, was not reduced significantly. The randomised trial that began in 2012 should reveal whether the use of short-term inpatient DBT can lead to a faster decline of suicidal and self-injurious behaviour than does standard outpatient DBT.


Asunto(s)
Terapia Conductista/métodos , Trastorno de Personalidad Limítrofe/terapia , Calidad de Vida , Adulto , Trastorno de Personalidad Limítrofe/psicología , Femenino , Hospitalización , Humanos , Proyectos Piloto , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Adulto Joven
10.
Andrologia ; 43(6): 392-7, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21848872

RESUMEN

Preservation of spermatozoa is an important aspect of assisted reproductive medicine. The aim of this study was to investigate the efficacy and use of a recently developed liquid nitrogen and cryogen-free controlled rate freezer and this compared with the classical liquid nitrogen vapour freezing method for the cryopreservation of human spermatozoa. Ten patients entering the IVF programme donated semen samples for the study. Samples were analysed according to the World Health Organization guidelines. No significant difference in total sperm motility after freeze-thawing between the new technique and classical technique was demonstrated. The advantage of the new freezing technique is that it uses no liquid nitrogen during the freezing process, hence being safer to use and clean room compatible. Investment costs are higher for the apparatus but running costs are only 1% in comparison with classical liquid nitrogen freezing. In conclusion, post-thaw motility of samples frozen with the classical liquid nitrogen vapour technique was comparable with samples frozen with the new nitrogen-free freezing technique. This latter technique can thus be a very useful asset to the sperm cryopreservation laboratory.


Asunto(s)
Criopreservación/métodos , Equipos y Suministros , Congelación , Nitrógeno , Preservación de Semen , Costos y Análisis de Costo , Humanos , Masculino
11.
Andrologia ; 43(3): 174-9, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21561463

RESUMEN

In the human, male ageing results in reproductive hormonal and cellular changes that can influence semen quality (volume, motility, concentration and morphology) and ultimately result in a reduced fertilising capacity and a longer 'time to pregnancy' for ageing men as well as an increased risk for miscarriage. This prospective cohort study of 278 patients undergoing a first in vitro fertilisation or intracytoplasmic sperm injection treatment was undertaken to examine whether patient's age was reflected in sperm motility, concentration, morphology as well as in DNA fragmentation (DFI) and immature chromatin (unprocessed nuclear proteins and/or poorly condensed chromatin) as measured by the sperm chromatin structure assay. This study also investigated the possible influence of male age (after correcting for female age) on their fertilising capacity, on obtaining a pregnancy and a healthy baby at home. Logistic regression analysis did not reveal any male age-related influences on sperm parameters like concentration, motility or morphology. No significant male age-related increase in DFI or immature chromatin was demonstrable for these patients. Elevated male age, after correcting for female age, was not related to lower fertilisation rates or significant decreases in the chance for a healthy baby at home.


Asunto(s)
Envejecimiento/fisiología , Ensamble y Desensamble de Cromatina/fisiología , Fertilización In Vitro , Edad Paterna , Análisis de Semen , Inyecciones de Esperma Intracitoplasmáticas , Espermatozoides/fisiología , Adulto , Estudios de Cohortes , Fragmentación del ADN , Femenino , Humanos , Masculino , Embarazo , Índice de Embarazo , Motilidad Espermática , Resultado del Tratamiento
12.
J Neurosci ; 29(10): 3132-7, 2009 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-19279250

RESUMEN

During active movement the electric potentials measured from the surface of the motor cortex exhibit consistent modulation, revealing two distinguishable processes in the power spectrum. At frequencies <40 Hz, narrow-band power decreases occur with movement over widely distributed cortical areas, while at higher frequencies there are spatially more focal power increases. These high-frequency changes have commonly been assumed to reflect synchronous rhythms, analogous to lower-frequency phenomena, but it has recently been proposed that they reflect a broad-band spectral change across the entire spectrum, which could be obscured by synchronous rhythms at low frequencies. In 10 human subjects performing a finger movement task, we demonstrate that a principal component type of decomposition can naively separate low-frequency narrow-band rhythms from an asynchronous, broad-spectral, change at all frequencies between 5 and 200 Hz. This broad-spectral change exhibited spatially discrete representation for individual fingers and reproduced the temporal movement trajectories of different individual fingers.


Asunto(s)
Electroencefalografía/métodos , Dedos/fisiología , Corteza Motora/fisiología , Movimiento/fisiología , Adolescente , Adulto , Mapeo Encefálico/métodos , Corteza Cerebral/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estimulación Luminosa/métodos , Desempeño Psicomotor/fisiología , Factores de Tiempo , Adulto Joven
13.
Hum Reprod ; 24(12): 3108-18, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19726447

RESUMEN

BACKGROUND: Cross-border reproductive care indicates the cross-border movements made by patients to obtain infertility treatment they cannot obtain at home. The problem at present is that empirical data on the extent of the phenomenon are lacking. This article presents the data on infertility patients going to Belgium for treatment. METHODS: A survey was conducted among the centres for reproductive medicine that are allowed to handle oocytes and create embryos (B-centres). Data were collected on the nationality of patients and the type of treatment for which they attended during the period 2000-2007. RESULTS: Sixteen of 18 centres responded to the questionnaire. The flow of foreign patients has stabilized since 2006 at approximately 2100 patients per year. The majority of foreign nationals seeking treatment in Belgium were French women for sperm donation. The next highest group was patients entering the country to obtain ICSI with ejaculated sperm. CONCLUSIONS: There are clear indications that numerous movements are motivated by the wish to evade legal restrictions in one's home country, either because the technology is prohibited or because the patients have characteristics, which exclude them from treatment in their own countries.


Asunto(s)
Infertilidad/terapia , Turismo Médico/estadística & datos numéricos , Servicios de Salud Reproductiva/estadística & datos numéricos , Técnicas Reproductivas Asistidas/estadística & datos numéricos , Adulto , Bélgica , Femenino , Francia/etnología , Encuestas de Atención de la Salud , Humanos , Inseminación Artificial Heteróloga/estadística & datos numéricos , Masculino , Turismo Médico/tendencias , Persona de Mediana Edad , Programas Nacionales de Salud/legislación & jurisprudencia , Programas Nacionales de Salud/estadística & datos numéricos , Países Bajos/etnología , Selección de Paciente , Diagnóstico Preimplantación/estadística & datos numéricos , Técnicas Reproductivas Asistidas/legislación & jurisprudencia , Inyecciones de Esperma Intracitoplasmáticas/estadística & datos numéricos , Adulto Joven
14.
J Vis ; 8(5): 16.1-18, 2008 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-18842087

RESUMEN

At the onset of bistable stimuli, the brain needs to choose which of the competing perceptual interpretations will first reach awareness. Stimulus manipulations and cognitive control both influence this choice process, but the underlying mechanisms and interactions remain poorly understood. Using intermittent presentation of bistable visual stimuli, we demonstrate that short interruptions cause perceptual reversals upon the next presentation, whereas longer interstimulus intervals stabilize the percept. Top-down voluntary control biases this process but does not override the timing dependencies. Extending a recently introduced low-level neural model, we demonstrate that percept-choice dynamics in bistable vision can be fully understood with interactions in early neural processing stages. Our model includes adaptive neural processing preceding a rivalry resolution stage with cross-inhibition, adaptation, and an interaction of the adaptation levels with a neural baseline. Most importantly, our findings suggest that top-down attentional control over bistable stimuli interacts with low-level mechanisms at early levels of sensory processing before perceptual conflicts are resolved and perceptual choices about bistable stimuli are made.


Asunto(s)
Adaptación Fisiológica/fisiología , Atención/fisiología , Conducta de Elección/fisiología , Visión Binocular/fisiología , Percepción Visual/fisiología , Adulto , Toma de Decisiones , Movimientos Oculares/fisiología , Humanos , Modelos Neurológicos , Estimulación Luminosa , Disparidad Visual/fisiología , Volición/fisiología , Adulto Joven
15.
J Vis ; 7(8): 10, 2007 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-17685817

RESUMEN

Existing neural explanations of spontaneous percept switching under steady viewing of an ambiguous stimulus do not fit the fact that stimulus interruptions cause the same percept to reappear across many ON/OFF cycles. We present a simple neural model that explains the observed behavior and predicts several more complicated percept sequences, without invoking any "high-level" decision making or memory. Percept choice at stimulus onset, which differs fundamentally from standard percept switching, depends crucially on a hitherto neglected interaction between local "shunting" adaptation and a near-threshold neural baseline. Stimulus ON/OFF timing then controls the generation of repeating, alternating, or more complex choice sequences. Our model also explains "priming" versus "habituation" effects on percept choice, reinterprets recent neurophysiological data, and predicts the emergence of hysteresis at the level of percept sequences, with occasional noise-induced sequence "hopping."


Asunto(s)
Adaptación Fisiológica/fisiología , Redes Neurales de la Computación , Vías Visuales/fisiología , Percepción Visual/fisiología , Habituación Psicofisiológica , Humanos , Dinámicas no Lineales , Psicofísica
16.
Biochim Biophys Acta ; 1387(1-2): 275-90, 1998 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-9748628

RESUMEN

Papaya glutamine cyclotransferase (PQC), present in the laticiferous cells of the tropical species Carica papaya, was purified near to homogeneity. Starting from the soluble fraction of the collected plant latex, a combination of ion-exchange chromatography on SP-Sepharose Fast Flow, hydrophobic interaction chromatography on Fractogel TSK Butyl-650 and affinity chromatography on immobilized trypsin provided a purification factor of 279 with an overall yield of 80%. In the course of the purification procedure, the two solvent accessible thiol functions located on the hydrophobic surface of the enzyme were converted into their S-methylthioderivatives. Papaya QC, a glycoprotein with a molecular mass of 33000 Da, contains a unique and highly basic polypeptide chain devoid of disulfide bridges as well as of covalently attached phosphate groups. Its absorption spectrum is dominated by the chromophores tyrosine which, nonetheless, do not contribute to the fluorescence emission of the plant enzyme. With a lambdamax of emission at 338 nm and a moderate susceptibility to be quenched by acrylamide, most of the tryptophyl residues of papaya QC appear to be sterically shielded by surrounding protein atoms. Fluorescence can thus be used to monitor unfolding of this enzyme. Preliminary experiments show that papaya QC is exceptionally resistant to chemical (guanidinium hydrochloride), acid and thermal denaturation. At first sight also, this enzyme exhibits high resistance to proteolysis by the papaya cysteine proteinases, yet present in great excess (around 100 mol of proteinases per mol of PQC) in the plant latex. Altogether, these results awaken much curiosity and interest to further investigate how the structure of this plant enzyme is specified.


Asunto(s)
Aminoaciltransferasas/química , Proteínas de Plantas/química , Acrilamida/farmacología , Cisteína Endopeptidasas/metabolismo , Glicoproteínas/química , Guanidina/farmacología , Concentración de Iones de Hidrógeno , Látex/química , Desnaturalización Proteica , Pliegue de Proteína , Espectrometría de Fluorescencia , Temperatura , Triptófano/fisiología
17.
Food Chem ; 189: 27-37, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26190597

RESUMEN

Food producing animals are exposed to biologically active plant compounds through feed and roughages, presenting a potential risk to the animal but also consumers of food of animal origin. To evaluate to which plant compounds of concern dairy cows in the Netherlands are exposed, a ranking filter model was developed, combining information on abundance of plant species in vegetation plots in the Netherlands (183,905 plots of three different vegetation types) with plant-compound combinations (700), and with consumption data of fresh grass, grass silage and corn silage by cattle. The most abundant plant genera are those producing cyanogenic glycosides, coumarins and benzofuranocoumarins, being predominantly fodder plants (alfalfa, clover and some grasses) considered to be safe. Highest exposures were estimated for plant genera producing piperidine alkaloids (horsetail), furanocoumarins (parsley and relatives), pyrrolizidine alkaloids (Symphytum, Senecio, Leucanthemum, Eupatorium) and essential oils. The current results allow to prioritise future scientific research on these compounds.


Asunto(s)
Alimentación Animal/análisis , Ensilaje/análisis , Animales , Bovinos , Fibras de la Dieta/análisis , Contaminación de Alimentos/análisis , Furanos/análisis , Furocumarinas/análisis , Medicago sativa/química , Modelos Teóricos , Aceites Volátiles/análisis , Oxalatos/análisis , Poaceae/química , Alcaloides de Pirrolicidina/análisis , Saponinas/análisis , Zea mays/química
18.
Phys Rev Lett ; 84(2): 326-9, 2000 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-11015902

RESUMEN

We study equilibrium crystal shapes (ECS) near facet ridge end points (FRE) by means of a numerical study of a body-centered solid-on-solid model on a square lattice with an enhanced uniaxial interaction range. This tests the stability of the so-called stochastic FRE point where the model maps exactly onto one dimensional Kardar-Parisi-Zhang-type growth and where the local ECS is simple. We find that the generic shapes are more complex. They contain first-order faceted to rough boundaries terminating in Pokrovsky-Talapov-type end points, and first-order ridges inside the rounded part of the ECS where two rough surface orientations coexist.

19.
Phys Rev Lett ; 84(17): 3891-4, 2000 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-11019232

RESUMEN

We point out how geometric features affect the scaling properties of nonequilibrium dynamic processes, by a model for surface growth where particles can deposit and evaporate only in dimer form, but dissociate on the surface. Pinning valleys (hilltops) develop spontaneously and the surface facets for all growth (evaporation) biases. More intriguingly, the scaling properties of the rough one dimensional equilibrium surface are anomalous. Its width, W approximately Lalpha, diverges with system size L as alpha = 1 / 3 instead of the conventional universal value alpha = 1 / 2. This originates from a topological nonlocal evenness constraint on the surface configurations.

20.
Fertil Steril ; 59(6): 1245-50, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8495773

RESUMEN

OBJECTIVE: To limit the high number of multiple pregnancies in an IVF program. SETTING: In Vitro Fertilization Laboratory, Fertility Department, Public Hospital. INTERVENTIONS: The number of embryos transferred was limited to two instead of three. RESULTS: Limiting the number of embryos transferred to only two did not influence the take home baby rate but eliminated triplet and quadruplet gestations. Moreover, the number of patients with good quality supernumerary embryos available for cryopreservation increased. CONCLUSIONS: To reduce the high frequency of multiple gestations in an IVF program, the number of embryos replaced should be limited to a maximum of two.


Asunto(s)
Fertilización In Vitro , Embarazo Múltiple , Criopreservación , Parto Obstétrico , Implantación del Embrión , Transferencia de Embrión/métodos , Embrión de Mamíferos , Femenino , Humanos , Embarazo
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