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排序方式: 共有597条查询结果,搜索用时 31 毫秒
591.
592.
Background
Nasal modes of respiratory support cause variable amounts of gastric dilatation which may increase gastro-oesophageal reflux (GER) in preterms. To compare the incidence of GER in nasally ventilated, preterm babies with controls (babies not on ventilation). Type of study: A prospective, observational comparative study.Method
Twenty-three preterm babies of gestational age 28–36 weeks and weight ranging between 1,000 g and < 2,500 g on either nasal continuous positive airway pressure (nCPAP) or nasal intermittent positive pressure venti-lation (nIPPV) were assessed for GER. They were compared with controls not on ventilation some of who were test babies when off ventilation (subgroup A) and some were unrelated babies not on ventilator but matched for gestational age and weight with test babies (subgroup B). All babies were subjected to continuous, oesophageal pH monitoring with dual sensor (upper and lower oesophageal) catheters. Reflux index (RI) was calculated as the percentage of study time the lower oesophageal pH was < 4. Primary outcome was the RI in the test and controls groups. Secondary outcome was the temporal relation of the reflux with symptoms if any. Numerical data were shown as mean with standard deviation and statistical comparisons were done using the χ2-test, Fischer test, and t-test wherever applicable.Results
The RI was higher in ventilated babies as compared to the control group, particularly in the subgroup A, where test babies formed their own controls. Grade IV reflux (7 cases) was seen only in the ventilated babies. There was no difference in the incidence of GER in babies on nCPAP as compared with nIPPV. Grade IV reflux could not be reliably predicted by RI alone. No definite temporal relation between episodes of reflux and symptoms could be determined in this study.Conclusion
There is an increase in GER in preterms on nasal modes of ventilation. A combination of upper (pharyngeal) and lower oesophageal sensors are preferred to a single lower oesophageal sensor when assessing GER by oesophageal pHmetry in neonates. 相似文献593.
594.
Linkage and physical mapping of X-linked lissencephaly/SBH (XLIS): a gene causing neuronal migration defects in human brain 总被引:6,自引:2,他引:6
Ross ME; Allen KM; Srivastava AK; Featherstone T; Gleeson JG; Hirsch B; Harding BN; Andermann E; Abdullah R; Berg M; Czapansky-Bielman D; Flanders DJ; Guerrini R; Motte J; Mira AP; Scheffer I; Berkovic S; Scaravilli F; King RA; Ledbetter DH; Schlessinger D; Dobyns WB; Walsh CA 《Human molecular genetics》1997,6(4):555-562
While disorders of neuronal migration are associated with as much as 25% of
recurrent childhood seizures, few of the genes required to establish
neuronal position in cerebral cortex are known. Subcortical band
heterotopia (SBH) and lissencephaly (LIS), two distinct neuronal migration
disorders producing epilepsy and variable cognitive impairment, can be
inherited alone or together in a single pedigree. Here we report a new
genetic locus, XLIS, mapped by linkage analysis of five families and
physical mapping of a balanced X;2 translocation in a girl with LIS.
Linkage places the critical region in Xq21-q24, containing the breakpoint
that maps to Xq22.3-q23 by high-resolution chromosome analysis. Markers
used for somatic cell hybrid and fluorescence in situ hybridization
analyses place the XLIS region within a 1 cM interval. These data suggest
that SBH and X-linked lissencephaly are caused by mutation of a single
gene, XLIS, that the milder SBH phenotype in females results from random
X-inactivation (Lyonization), and that cloning of genes from the breakpoint
region on X will yield XLIS.
相似文献
595.
Juul A; Scheike T; Pedersen AT; Main KM; Andersson AM; Pedersen LM; Skakkebaek NE 《Human reproduction (Oxford, England)》1997,12(10):2123-2128
Few studies exist on the physiological changes in the concentrations of
growth hormone (GH), insulin-like growth factors (IGF) and IGF-binding
proteins (IGFBP) within the menstrual cycle, and some controversy remains.
We therefore decided to study the impact of endogenous sex steroids on the
GH-IGF-IGFBP axis during the ovulatory menstrual cycle in 10 healthy women
(aged 18-40 years). Blood sampling and urinary collection was performed
every morning at 0800 h for 32 consecutive days. Every second day the
subjects were fasted overnight before blood sampling. Follicle stimulating
hormone, luteinizing hormone (LH), oestradiol, progesterone, IGF-I,
IGFBP-3, sex hormone-binding globulin, dihydroepiandrosterone sulphate and
GH were determined in all samples, whereas insulin and IGFBP-1 were
determined in fasted samples only. Serum IGF-I concentrations showed some
fluctuation during the menstrual cycle, with significantly higher values in
the luteal phase compared to the proliferative phase (P < 0.001). Mean
individual variation in IGF-I concentrations throughout the menstrual cycle
was 13.2% (SD 4.3; range 0.1-18.3%). There were no cyclic changes in
IGFBP-3 serum concentrations and no differences in IGFBP-3 concentrations
between the luteal and the proliferative phases. Mean individual variation
in IGFBP- 3 concentrations throughout the menstrual cycle was 8.8% (SD 2.7;
range 3.2-14.1). IGFBP-1 concentrations were inversely associated with
insulin concentrations, and showed a significant pre-ovulatory increase
that returned to baseline at the day of the LH surge. Fasting insulin
concentrations showed large fluctuations throughout the menstrual cycle
without any distinct cyclic pattern. No cyclic changes in urinary GH
excretion during menstrual cycle were detected. We conclude that, although
IGF-I concentrations are dependent on the phase of the menstrual cycle, the
variation in IGF-I concentrations throughout the menstrual cycle is
relatively small. Therefore, the menstrual cycle does not need to be
considered when evaluating IGF-I or IGFBP-3 serum values in women suspected
to have GH deficiency.
相似文献
596.
KM AlGhamdi 《Journal of the European Academy of Dermatology and Venereology》2009,23(11):1282-1288
Background There are concerns that there is no uniform approach towards the management of vitiligo.
Objectives To explore attitudes and strategies for the management of vitiligo among dermatologists.
Methods A self-administered questionnaire containing 22 questions was distributed to 160 dermatologists attending a national dermatology conference in 2007.
Results One hundred and twelve dermatologists responded to the questionnaire (70% response rate). We had 105 completed questionnaires (seven were excluded due to incompleteness). Active treatment of vitiligo was recommended by 96% in more than half of patients, while 79% recommended treatment at non-visible sites. Repigmentation was regarded as main treatment goal by 54%. Mid-potent topical steroids were widely prescribed for focal vitiligo (72% in children and 65% in adults). Use of tacrolimus and pimecrolimus was limited. The most common used phototherapy was 'narrowband ultraviolet B' (NBUVB; 36% and 40% for generaliased vitiligo in children and adults, respectively). The use of oral psoralen plus UVA (PUVA) was limited (8% for generalized vitiligo in adults). Few respondents (1–8% for different types of vitiligo) prescribed outdoor topical PUVA. Vitiligo surgery was advised mainly for segmental type (18% in adults and 5% in children). Depigmentation was the first option for universal vitiligo by 50% and 30% in adults and children, respectively.
Conclusions Most dermatologists are enthusiastic about active treatment of vitiligo even in hidden sites. Overall, the most two common treatment modalities were topical steroids and NBUVB. Vitiligo surgery is underutilized. Development of national practice guidelines is needed. 相似文献
Objectives To explore attitudes and strategies for the management of vitiligo among dermatologists.
Methods A self-administered questionnaire containing 22 questions was distributed to 160 dermatologists attending a national dermatology conference in 2007.
Results One hundred and twelve dermatologists responded to the questionnaire (70% response rate). We had 105 completed questionnaires (seven were excluded due to incompleteness). Active treatment of vitiligo was recommended by 96% in more than half of patients, while 79% recommended treatment at non-visible sites. Repigmentation was regarded as main treatment goal by 54%. Mid-potent topical steroids were widely prescribed for focal vitiligo (72% in children and 65% in adults). Use of tacrolimus and pimecrolimus was limited. The most common used phototherapy was 'narrowband ultraviolet B' (NBUVB; 36% and 40% for generaliased vitiligo in children and adults, respectively). The use of oral psoralen plus UVA (PUVA) was limited (8% for generalized vitiligo in adults). Few respondents (1–8% for different types of vitiligo) prescribed outdoor topical PUVA. Vitiligo surgery was advised mainly for segmental type (18% in adults and 5% in children). Depigmentation was the first option for universal vitiligo by 50% and 30% in adults and children, respectively.
Conclusions Most dermatologists are enthusiastic about active treatment of vitiligo even in hidden sites. Overall, the most two common treatment modalities were topical steroids and NBUVB. Vitiligo surgery is underutilized. Development of national practice guidelines is needed. 相似文献
597.