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排序方式: 共有2179条查询结果,搜索用时 15 毫秒
1.
Marieke Peeters Ludo Verhoeven Jan de Moor Hans van Balkom 《Research in developmental disabilities》2009,30(4):712-726
The goal of this longitudinal study was to investigate the precursors of early reading development in 52 children with cerebral palsy at kindergarten level in comparison to 65 children without disabilities. Word Decoding was measured to investigate early reading skills, while Phonological Awareness, Phonological Short-term Memory (STM), Speech Perception, Speech Production and Nonverbal Reasoning were considered reading precursors. Children with cerebral palsy lag behind on all reading precursors at the beginning of the second year of kindergarten. For the children without disabilities, early reading skills in Grade 1 were best predicted by Phonological Awareness and Phonological STM while Speech Production was the most important predictor of early reading success for the children with cerebral palsy, followed by Phonological Awareness and Speech Perception. Furthermore, for children with cerebral palsy, Speech Production appears to dominate reading development, as Speech Production measured at the beginning of the second year of kindergarten was strongly predictive of all other reading precursors measured at the end of the second year of kindergarten. The results of this study reveal that children with cerebral palsy with additional speech impairments are at risk for limited literacy development. Clinical implications are discussed. 相似文献
2.
It is demonstrated that tubular fragments derived from human testes and cultured in vitro produce a factor that stimulates the production of testosterone by human interstitial cells and by Percoll-purified Leydig cells from rat and mouse origin. The active principle in the conditioned media is a thermo-labile and trypsin-sensitive protein with an MW greater than 10,000. The factor is active in the presence as well as in the absence of maximally effective concentrations of LH and its activity is not accompanied by measurable changes in cAMP production. There are several points of analogy between this factor and a Leydig cell stimulatory protein produced by rat Sertoli cells. Molecular weight fractionation of spent media from human testicular tubules using an Amicon ultrafiltration system results in a 38- to 102-fold increase in Leydig cell stimulatory activity in a fraction corresponding to a molecular weight of 10,000 up to 30,000. These figures are comparable to those observed after molecular weight fractionation of spent media from rat Sertoli cells. Dose-response curves with partially purified preparations from human and rat origin yield parallel dose-response curves. In rat Sertoli cells as well as in human testicular tubules, the production of the active principle is stimulated by FSH and dibutyryl cAMP. Finally, maximally effective concentrations of the active principles of human and rat origin display no additive effects whereas additive effects are clearly evident with other Leydig cell stimulatory factors such as LHRHa and EGF. The hypothesis is advanced that the Leydig cell stimulatory factors from tubular origin may act as paracrine regulatory molecules responsible for the effects of FSH on Leydig cell function. 相似文献
3.
4.
Male subfertility induced by acute scrotal heating affects embryo quality in normal female mice 总被引:5,自引:0,他引:5
Jannes P; Spiessens C; Van der Auwera I; D'Hooghe T; Verhoeven G; Vanderschueren D 《Human reproduction (Oxford, England)》1998,13(2):372-375
The aim of this experiment was to design a suitable mouse model for male
subfertility in which to study the effect of decreased sperm quality on
embryo quality in vivo and in vitro. To achieve male subfertility, testes
of adult male mice were immersed in water at either 42 degrees C (heated)
or 33 degrees C (controls) during 20 min. Twenty-eight days after
treatment, all heat stressed males showed a significant decrease in
relative testis weight [384.7 mg in controls (286.7-460.6) versus 323 mg in
stress heated groups (117.9-405.6); P < 0.001], sperm concentration
[3.75 x 10(6)/ml (2.75-7.25) versus 1.00 x 10(6)/ml (0-4.00); P < 0.001]
and progressive sperm motility [57.5% (48.0-79.0) versus 42.5% (14.0-66.0);
P < 0.001]. Moreover, after mating to heat exposed males, not only the
number of pregnant females (20/22 versus 18/30) but also the weight of
their embryos [275.4 mg (78.7-339.4) versus 261.8 mg (68.1-339.0); P <
0.001] was significantly lower at 14.5 days post coitum when compared to
controls. Neither the number of resorption sites nor the number of viable
embryos per pregnant female was significantly different between groups.
Also, the in-vitro fertilization rate of oocytes, fertilized by spermatozoa
collected from heat stressed males, was significantly lower (44.9%; P <
0.0001) when compared to controls (65.1%; P < 0.0001). In conclusion,
the results of this study suggest that male subfertility induced by acute
scrotal heating may result in impaired sperm quality, reduced embryo weight
in vivo and decreased fertilization rate in vitro.
相似文献
5.
6.
Pyomyositis: characteristics at CT and MR imaging 总被引:9,自引:0,他引:9
7.
AJ Larner MRCP 《International journal of clinical practice》1994,48(5):272-274
SUMMARY A case is reported of pseudohyperphosphataemia in association with a monoclonal gammopathy of undetermined significance. 相似文献
8.
Lieve Peremans Veronique Verhoeven Hilde Philips Joke Denekens Paul Van Royen 《The European journal of contraception & reproductive health care》2007,12(4):317-325
OBJECTIVE: To evaluate how Belgian health care providers deal with a request for emergency contraception. METHOD: In 2002-2003 we conducted 12 focus groups with pharmacists, general practitioners and school physicians. A skilled moderator accompanied by an observer conducted the focus groups using a semi-structured screenplay. RESULTS: All these health care providers agree with the free access to emergency contraception (EC), but experience considerable frustration with regard to the practical aspects and the legal framework. General practitioners (GPs) claim to spend a lot of time on requests for EC and they are concerned about the quality of the counselling provided in pharmacies. Pharmacists are creative when giving counselling in the pharmacy, but there is, nevertheless, a problem with a lack of privacy. School physicians are frustrated that there is no legal possibility to respond to a request for EC when they feel they are ideally placed to advise adolescents. CONCLUSION: The over-the-counter sale of EC offers women better access, but many barriers still interfere with optimal care. Pharmacists experience a lack of skills to communicate with adolescents and a lack of privacy to give counselling. GPs have good intentions, but are confronted with a lack of willingness on the part of the patients and also financial barriers. School physicians want more possibilities to help adolescents. 相似文献
9.
10.
D De AJ Kanwar S Handa 《Journal of the European Academy of Dermatology and Venereology》2006,20(7):853-859
BACKGROUND: Diagnosis of atopic dermatitis (AD) depends on clinical features because no definitive diagnostic test exists. Criteria proposed by Hanifin and Rajka (Acta Derm Venereol (Stockh) 1980; Suppl 92: 44-47) were acceptable for hospital-based studies but were found not to be suitable for field studies. A UK working party formulated clinical diagnostic criteria that could be used in both hospital and epidemiological settings. Validation studies of the criteria showed widely variable results, probably due to different clinical settings and ethnicity. AIM AND OBJECTIVE: This study was undertaken to validate Hanifin and Rajka's criteria and to assess the comparative efficacy of their criteria and the UK working party's diagnostic criteria in the diagnosis of AD in a hospital setting in North India. SUBJECTS AND METHODS: This study serially included 101 patients with AD and 48 controls of paediatric age group. The study period was from July 2003 to December 2004. RESULTS: Hanifin and Rajka's criteria (sensitivity 96%, specificity 93.75%, positive predictive value 97% (PPV) and negative predictive value (NPV) 91.84%) had a statistical advantage over the UK working party's diagnostic criteria (sensitivity 86%, specificity 95.83%, PPV 97.75% and NPV 76.67%), with a P-value < 0.005. 相似文献