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排序方式: 共有813条查询结果,搜索用时 15 毫秒
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Römkens M Gordijn B Verhaak CM Meuleman EJ Braat DD 《Nederlands tijdschrift voor geneeskunde》2005,149(18):992-995
OBJECTIVE: To identify medical and psychosocial risks that could arise from allowing older men to father children through in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI). DESIGN: Literature review. METHOD: The databases Medline, Current Contents weekly, Current Contents archives, and PsycINFO were searched over the period 1970--June 2004 for articles with data on age limits for men entering IVF/ICSI programmes. The following inclusion criteria were used: availability in the Netherlands and written in English or Dutch. RESULTS: Although sperm quality decreases with age, men remain fertile up to an advanced age. The risks of having children with autosomal dominant disorders or chromosomal defects increase slightly, but the individual chance is extremely small. Studies on the psychological development of children with fathers aged > 50 years are lacking. Extrapolation from other studies indicates that growing up with an older father has no negative influence on child development. Although older fathers have a greater chance of dying sooner, the absence of the father does not contribute significantly to psychological problems in offspring later in life. CONCLUSION: There are no medical or psychosocial arguments to support an age limit for men entering an IVF/ICSI programme. 相似文献
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Multispectral analysis of magnetic resonance images 总被引:1,自引:0,他引:1
Magnetic resonance (MR) imaging systems produce spatial distribution estimates of proton density, relaxation time, and flow, in a two dimensional matrix form that is analogous to that of the image data obtained from multispectral imaging satellites. Advanced NASA satellite image processing offers sophisticated multispectral analysis of MR images. Spin echo and inversion recovery pulse sequence images were entered in a digital format compatible with satellite images and accurately registered pixel by pixel. Signatures of each tissue class were automatically determined using both supervised and unsupervised classification. Overall tissue classification was obtained in the form of a theme map. In MR images of the brain, for example, the classes included CSF, gray matter, white matter, subcutaneous fat, muscle, and bone. These methods provide an efficient means of identifying subtle relationships in a multi-image MR study. 相似文献
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Reasons for dropout in an in vitro fertilization/intracytoplasmic sperm injection program 总被引:7,自引:0,他引:7
OBJECTIVE: To gain more insight into psychological aspects of dropping out from IVF-ICSI. DESIGN: Prospective cohort study. SETTING: University hospital-based tertiary care fertility clinic. PATIENT(S): Women entering their first treatment cycle of IVF or ICSI. INTERVENTION(S): Standardized psychological questionnaires were administered before the start of the treatment and after treatment. MAIN OUTCOME MEASURE(S): Reasons for dropout, state and trait anxiety, depression, and marital and sexual satisfaction. RESULT(S): Baseline psychological factors and the probability of dropout after IVF-ICSI treatment were found to be associated in the group that stopped treatment for psychological reasons. Those who were denied further treatment by the medical team, the "actively censored" group, did not show pretreatment differences regarding psychological measures in comparison with those who continued treatment. After treatment, the group that was denied further treatment showed higher levels of anxiety and depression compared with those that continued. CONCLUSION(S): Dropout, being a well-known phenomenon in IVF-ICSI, is related to preexisting psychological factors in IVF-ICSI. Actively censored patients were psychologically well-adjusted before treatment, but this changed after censoring. 相似文献
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Zwaanswijk M Verhaak PF Bensing JM van der Ende J Verhulst FC 《European child & adolescent psychiatry》2003,12(4):153-161
In order to understand the discrepancy between rates of
child and adolescent psychopathology and rates of mental health
service use, variables influencing the help-seeking process need
to be investigated. The present article aims to extend and
refine previous findings by reviewing 47 recent empirical
studies on parental and adolescent problem recognition and help
seeking, and problem recognition by the general practitioner
(GP). Several variables (child age, the presence of medical and
school-related problems, informal help seeking, past treatment
of parents or relatives, family size, and type of maltreatment)
were discovered to influence parental/adolescent problem
recognition and/or help seeking,while refinements were found for
the effects of type of psychopathology, child gender, adolescent
attitudes and personality, parental psychopathology, social
support, and sociodemographic variables. Although recent studies
uncovered several determinants of problem recognition by the GP
(child gender, age, past treatment, academic problems, family
composition, life events, type of visit, and acquaintance with
child), this aspect of the help-seeking pathway remains
relatively uncharted and, therefore, needs to be the focus of
future research. 相似文献