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991.
A L Ogilvy-Stuart D J Clark W H Wallace B E Gibson R F Stevens S M Shalet M D Donaldson 《Archives of disease in childhood》1992,67(9):1107-1110
Endocrine function was assessed in 31 children (17 boys) after fractionated total body irradiation used in the preparative regimen for bone marrow transplantation. Endocrine dysfunction was present in 25 children. Fifteen of 29 had growth hormone insufficiency 0.9-4.9 years after total body irradiation, yet only three of the 15 had received previous cranial irradiation. Five of 30 had thyroid dysfunction: two with a low thyroxine and raised thyroid stimulating hormone (TSH) concentration and three with a raised TSH and normal thyroxine concentration. Thus the incidence of thyroid dysfunction (16%) is much lower than that reported after single fraction total body irradiation (39-59%). In only two children were abnormalities of the hypothalamic-pituitary-adrenal axis demonstrated. The majority of pubertal children assessed (n = 15) showed evidence of gonadal damage. All the pubertal girls (n = 5) had ovarian failure, although there was evidence of recovery of ovarian function in one girl. All seven boys in late puberty showed evidence of damage to the germinal epithelium, and two of three in early puberty had raised follicle stimulating hormone concentrations. Despite the use of a fractionated total body irradiation regimen, endocrine morbidity is substantial and children undergoing such procedures will require long term endocrine review and management. 相似文献
992.
R M Clark 《Current opinion in obstetrics & gynecology》1992,4(4):601-607
Research is focused on defining high-risk factors associated with the development of breast cancer and occult metastatic disease in node-negative patients. The interaction between hormones and growth factors is being diligently investigated, both in the genesis of breast cancer and in metastases. The effect of oral contraceptives on breast pathology remains under close scrutiny. Screening mammography for young women is proving to be of doubtful value. 相似文献
993.
The significance of cone biopsy resection margins. 总被引:6,自引:0,他引:6
S Paterson-Brown O A Chappatte S K Clark A Wright P Maxwell N A Taub K S Raju 《Gynecologic oncology》1992,46(2):182-185
This 12-year retrospective study examines the significance of margin involvement with dysplasia at cone biopsy in relation to follow-up. Of 300 cone biopsies, 123 (41%) had margin involvement. These cases of margin involvement were associated with more severe dysplasia (P less than 0.0001) and a higher chance of subsequent abnormal cytological follow-up (P less than 0.0001) and residual dysplasia at subsequent surgery (P less than 0.0001). Involvement of the endocervical margin at the initial cone biopsy was a sensitive predictor of future abnormality, with an incidence of subsequent abnormal cytology of 29% and residual disease of 82% in those undergoing further surgery. In those cases where the margins had been clear, the incidence of abnormal cytological follow-up was 8%, with 12% residual disease in those undergoing subsequent surgery. Margin involvement was a better predictor of residual disease at repeat surgery than abnormal follow-up cytology (positive predictive value, 79% vs 60%, respectively). 相似文献
994.
A frequency-specific, objective assessment of hearing thresholds is required for use in subjects unable to perform behavioural audiometry. One such method using steady-state evoked potentials (SSEPs) in response to amplitude-modulated tones was evaluated in an experimental animal, the macaque monkey. An amplitude-modulation frequency of 165 Hz was found to produce optimum response detection in the anaesthetised animal. Auditory thresholds determined by a computerised automatic response detection system accurately reflected behavioural thresholds previously described in this species. 相似文献
995.
P J Blamey B C Pyman M Gordon G M Clark A M Brown R C Dowell R D Hollow 《The Annals of otology, rhinology, and laryngology》1992,101(4):342-348
A sample of 64 postlinguistically profoundly to totally deaf adult cochlear implant patients were tested without lipreading by means of the Central Institute for the Deaf (CID) sentence test 3 months postoperatively. Preoperative promontory stimulation results (thresholds, gap detection, and frequency discrimination), age, duration of profound deafness, cause of deafness, lipreading ability, postoperative intracochlear thresholds and dynamic ranges for electrical stimulation, depth of insertion of the electrode array into the scala tympani, and number of electrodes in use were considered as possible factors that might be related to the postoperative sentence scores. A multiple regression analysis with stepwise inclusion of independent variables indicated that good gap detection and frequency discrimination during preoperative promontory testing, larger numbers of electrodes in use, and greater dynamic ranges for intracochlear electrical stimulation were associated with better CID scores. The CID scores tended to decrease with longer periods of profound deafness. 相似文献
996.
The Spectral Maxima Sound Processor (SMSP) is a portable speech processor which has recently been developed at the University of Melbourne for use with multiple-electrode cochlear implants. In this processor, the six largest outputs (maxima) of 16 bandpass filters are used to stimulate the cochlea on a place basis at a constant rate. This speech processing strategy has been compared with the MSP(MULTIPEAK) strategy, in which four electrodes are selected for stimulation in every glottal pulse period. The study was undertaken on four postlinguistically deaf adults. The results show that, for this group of subjects, the performance of the SMSP processor was significantly better than that of the MSP(MULTIPEAK) processor for the recognition of closed-set vowels and consonants, open-set monosyllabic words, and open-set sentences in noise, when using electrical stimulation alone. The SMSP mean scores were: vowels 91.3%, consonants 74.9%, words 57.4%, and sentences in noise 78.7%. The MSP(MULTIPEAK) mean scores were: vowels 76.3%, consonants 59.4%, words 39.9%, and sentences in noise 50.0%. 相似文献
997.
Supernatants from mouse in vitro fertilized (IVF) oocyte cultures may suppress in vitro lymphocyte proliferation stimulated by concanavalin A (Sigma, St. Louis, MO). Supernatants conditioned by incubation with mouse epididymal sperm alone were even more inhibitory. Thin-layer chromatography suggested the polyamines spermine in sperm and spermine plus spermidine in IVF embryo supernatants were responsible. Putrescine was not suppressive. In vitro fertilized oocytes from old CBA/J-strain mice (greater than 20 weeks) that suffer age onset infertility lacked suppression and manifest cleavage arrest that could be partially reversed by adding spermine to the cultures. The failure of IVF oocytes to produce adequate quantities of polyamines could lead to failure of implantation due to division arrest. A possible in vivo role of polyamines as immunosuppressor factors is discussed. 相似文献
998.
999.
After the introduction of the colposcope for the examination of children suspected of being sexually abused in Leeds, a study was undertaken to describe the findings in detail. A total of 109 consecutive prepubertal girls, mean age 70.4 months were assessed including colposcopic genital and anal examination, and peer group review of reports and photographs. Fifty nine children had signs consistent with blunt force penetrating trauma (hymenal transection/major notch, scar, or hymenal attenuation). Transections were encountered most commonly at 6 o'clock (directly posterior). In 46 the hymenal orifice was gaping with thigh abduction only and in 47 the hymenal orifice transverse diameter was greater than 4 mm on labial separation. Overall, physical findings were commonly present and in only two cases were no signs recorded. Non-specific and frequent findings included patterns of labial and introital reddening. Supportive hymenal signs including swelling, rounding of edge, thickening, distortion, and loss of symmetry were common. Labial fusion was present in 20. Urethral dilatation with labial separation was noted in 14. Physical findings including normality are consistent with abuse and even minor anogenital signs as well as negative findings should be documented. Colposcopy and photography are valuable tools in peer review, teaching, and case management. 相似文献
1000.
AJ Blethyn HR Jenkins R Roberts K Verrier Jones 《Archives of disease in childhood》1995,73(6):534-535
Little objective evidence has been published to support the claim that constipation is an important contributory factor in recurrent urinary tract infection (UTI) in childhood. Using a radiological scoring system, two observers assessed faecal loading from abdominal radiographs of children with proved UTIs. There was a significant increase in the degree of faecal loading in children with UTI when compared with controls (r = 0.237). This difference was mainly accounted for by girls with recurrent (greater than five) UTIs. This study confirms an association between recurrent UTI and faecal loading. Further studies are needed to establish if there is a causal relationship and benefits from treatment. 相似文献