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61.
S F Wong A Lee-Tannock D Amaraddio F Y Chan H D McIntyre 《Ultrasound in obstetrics & gynecology》2006,28(7):934-938
OBJECTIVE: To assess the effect of glucose control on the rate of growth of fetuses in women with pregestational diabetes mellitus (Types 1 and 2). METHODS: All pregestational diabetic women booked at Mater Mothers' Hospital, Brisbane, Australia, between 1 January 1994 and 31 December 2002, were included. Pregnancies with congenital fetal anomalies, multiple pregnancies, and pregnancies terminated prior to 20 weeks' gestation were excluded. Dating scans were performed before 14 weeks' gestation and serial scans were performed at 18, 24, 28, 32 and 36 weeks. Fetal parameters, including biparietal diameter, femur length and abdominal circumference, were recorded. The daily growth rates for biparietal diameter, femur length, and fetal abdominal area were calculated and compared with those in a low-risk (non-diabetic) population. The growth rates in fetuses of women with satisfactory diabetic control (HbA1c < 6.5%) and unsatisfactory control (HbA1c > or = 6.5%) in the three trimesters were compared. RESULTS: A total of 174 diabetic pregnancies were included and a total of 997 ultrasound scans were performed. The growth rates for fetuses of mothers with diabetes mellitus were significantly higher than for those in the low-risk population. The z-scores for biparietal diameter, femur length, and fetal abdominal area were 0.18, 0.59 and 1.44, respectively. Fetuses of diabetic mothers with high HbA1c in the first trimester had significantly greater fetal abdominal area growth rate than those with normal HbA1c (fetal abdominal area z-score of 1.7 vs. 0.75, P = 0.009). Although the fetal abdominal area z-scores in fetuses of diabetic mothers with high HbA1c in the second or third trimesters were also higher than those with normal HbA1c levels, the differences did not reach statistical significance. Maternal obesity did not influence the fetal growth rate. CONCLUSION: The rate of growth of fetuses of diabetic mothers differs from that of the normal population. Growth acceleration persists until the late third trimester. Moreover, periconceptional glucose control appears to have a significant effect on accelerated growth of the fetal abdominal area. 相似文献
62.
We examined stochastic resonance with a differential coding scheme using a multilayer feedforward neural network which is composed of intra-layer connections. We show that the network, with random synaptic connections in each layer, encodes an input signal into a spike coherence that represents temporal differences among the inputs. We also demonstrate that both internal and external noise enhance the detection of weak signals. Finally, we discuss how the feedforward network with intra-layer random connections is similar to a membrane in its sensitivity to and amplification of a change in stimulus and suggest that the intensity of internal noise may be tuned in a real brain. 相似文献
63.
Chan C. H. Y Ng E. H. Y Chan C. L W 《世界核心医学期刊文摘》2006,2(6):15-15
目的:评价东部身体-智力-精神(EBMS)群体干预对进行体外受精(IVF)的中国妇女焦虑缓解的作用。设计:随机对照研究。机构:三级辅助生殖机构。受试者:227例接受第1个IVF周期治疗的妇女。干预:干预组(n=69)接受4次EBMS群体咨询,而对照组(n=115)无任何干预。主要观察指标:状态-特质焦虑问卷。结果:与对照组相比,干预组在干预后状态焦虑平均分显著下降。每组移植同样数目的卵子,但干预组没有明显更高妊娠率的倾向。 相似文献
64.
Eun Sang Park Jung Im Na Seon Ok Kim Chang Hun Huh Sang Woong Youn Kyoung Chan Park 《Skin research and technology》2006,12(4):298-302
Background/purpose: Vitiligo and nevus depigmentosus (ND) present similar hypopigmented macules with significantly different prognoses. Although the distinction between the two diseases is important, differential diagnosis relies on medical history and physical examination, which is far from decisive in some cases. The Mexameter® is an objective skin color-measuring device, and has been reported to provide a reproducible and sensitive means of quantifying small skin color differences. In this study, we investigated the usefulness of a Mexameter® for discriminating these diseases.
Methods: A selection of 202 hypopigmented skin lesions (182 from vitiligo and 20 from ND) were the objects of this study. Using a Mexameter, MIs were obtained from lesions and symmetrically located control skin. RMIs, ratios of the MIs of lesional skins to control skins, were calculated.
Results: The mean MIs and RMIs were significantly different for vitiligo and ND. The mean RMI of ND lesions was 74±13, which was significantly higher than that of vitiligo lesions (50±24). No ND lesion had an RMI of <50%.
Conclusion: This study shows that the Mexameter® , an objective pigment-measuring device, can be used to achieve a more accurate diagnosis of hypopigmentary disorders, and that the relative melanin index (RMI), which represents the relative pigment levels, might be a more effective parameter than the melanin index (MI) itself for comparing pigmentation differences. 相似文献
Methods: A selection of 202 hypopigmented skin lesions (182 from vitiligo and 20 from ND) were the objects of this study. Using a Mexameter, MIs were obtained from lesions and symmetrically located control skin. RMIs, ratios of the MIs of lesional skins to control skins, were calculated.
Results: The mean MIs and RMIs were significantly different for vitiligo and ND. The mean RMI of ND lesions was 74±13, which was significantly higher than that of vitiligo lesions (50±24). No ND lesion had an RMI of <50%.
Conclusion: This study shows that the Mexameter
65.
66.
Facial reanimation after acoustic neuroma excision is currently accomplished using a variety of surgical techniques. A multi-institutional survey of patient perceptions of facial reanimation success was accomplished by mailing a questionnaire to 809 randomly selected members of the Acoustic Neuroma Association. Four hundred sixty patients who underwent 296 reanimation procedures responded. Facial to hypoglossal nerve anastomosis, tarsorrhaphy, and upper eyelid implants were most frequently performed. The patient's estimations of initial deficit, spontaneous recovery, and overall satisfaction with the reanimation procedures are discussed. 相似文献
67.
Conditionally replicating luciferase reporter phages: improved sensitivity for rapid detection and assessment of drug susceptibility of Mycobacterium tuberculosis. 总被引:7,自引:1,他引:6
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C Carrire P F Riska O Zimhony J Kriakov S Bardarov J Burns J Chan W R Jacobs Jr 《Journal of clinical microbiology》1997,35(12):3232-3239
TM4 is a lytic mycobacteriophage which infects mycobacteria of clinical importance. A luciferase reporter phage, phAE40, has been constructed from TM4 and was previously shown to be useful for the rapid detection and drug susceptibility testing of Mycobacterium tuberculosis. However, the lytic nature of the phage results in a loss of detectable light output and limits the sensitivity of detection. We describe several strategies aimed at improving the luciferase activity generated by TM4 luciferase phages, including (i) varying the position of the luciferase gene in the phage genome, (ii) isolating host-range mutants of the phage, and (iii) introducing temperature-sensitive mutations in the phage such that it will not replicate at the infecting temperature. Several new phages generated by these methods show increased intensity of luciferase production compared to the first-generation reporter phage phAE40, and one phage, phAE88, also demonstrates an enhanced duration of luciferase activity. This has allowed the detection of as few as 120 BCG cells and the determination of drug susceptibilities of M. tuberculosis in as little as 1 day. 相似文献
68.
Dopamine differentially regulates dynorphin, substance P, and enkephalin expression in striatal neurons: in situ hybridization histochemical analysis. 总被引:14,自引:0,他引:14
Dopamine regulation of the levels of dynorphin, enkephalin, and substance P messenger RNAs in rat striatal neurons was analyzed with in situ hybridization histochemistry (ISHH). Relative levels of peptide mRNA expression in the patch and matrix compartments of the dorsolateral striatum were compared among control rats, rats treated for 10 d with apomorphine, rats with unilateral 6-hydroxydopamine (6-OHDA) lesions of the nigrostriatal dopaminergic system, and rats with nigrostriatal dopaminergic lesions followed 2 weeks later by 10 d of apomorphine treatment. Image analysis of ISHH labeling demonstrated that the number of neurons expressing each peptide mRNA remained constant, whereas the relative level of peptide mRNA per neuron changed significantly, depending on the experimental treatment. Dynorphin mRNA expression increased following chronic apomorphine treatment: striatal patch neurons increased to an average of 100% above control values, whereas striatal matrix neurons showed only a 25% increase. Dynorphin mRNA expression decreased following 6-OHDA lesions: patch neurons showed an average 75% reduction in expression, whereas matrix neurons showed no significant change. In animals with 6-OHDA lesions followed by apomorphine treatment, both patch and matrix neurons showed an average increase in dynorphin expression of 300% above control levels. Changes in dynorphin mRNA levels with these treatments were matched by qualitative changes in dynorphin immunoreactivity both in the striatum and in striatonigral terminals in the substantia nigra. Neither substance P nor enkephalin mRNA levels showed a significant difference between the striatal patch and matrix compartments in any experimental condition (in the dorsolateral striatum). Substance P mRNA expression was increased an average of 50% after 10 d of apomorphine treatment and showed an average decrease of 75% following 6-OHDA lesions of the mesostriatal system. There was no significant change in the expression of substance P mRNA in striatal neurons compared to control values in rats with combined 6-OHDA lesion and apomorphine treatment. Enkephalin mRNA expression was not significantly altered by chronic apomorphine treatment but showed an average increase per cell of some 130% above control levels following 6-OHDA-induced lesions of the mesostriatal system. In animals with a 6-OHDA lesion and apomorphine treatment, enkephalin mRNA was also elevated but not significantly above the levels produced by the lesions alone. These data show that the expression of dynorphin, enkephalin, and substance P is differentially regulated by the mesostriatal dopaminergic system and, further, suggests that the mechanisms by which this regulation occurs may be different for the 3 peptide families. 相似文献
69.
70.
Magnetic resonance imaging confirmation of resolution of periodontoid pannus formation following C1/C2 posterior transarticular screw fixation. 总被引:3,自引:0,他引:3
Chronic odontoid fractures are considered unstable spinal lesions. Chronic instability in this region leads to the development of an inflammatory pannus, which can progress resulting in spinal cord compression radiographically and a myelopathy syndrome clinically. In this report we document three cases of reversal of pannus after C1/C2 transarticular screw fixation of an unstable odontoid fracture. Three patients were identified with chronic odontoid fractures and spinal cord compression due to periodontoid pannus formation. All patients presented with a progressive myelopathy syndrome. All patients underwent preoperative and postoperative magnetic resonance imaging (MRI) of the craniovertebral junction. C1/C2 transarticular screw fixation was performed for stabilization of C1/C2. Postoperatively there were no complications. Postoperative MRI at 6 months demonstrated resolution of the ventral pannus. Moreover, all patients exhibited improvement of preoperative neurological deficits. MRI is the imaging technique of choice for diagnosis and follow-up of patients with chronic odontoid fractures and ventral pannus. C1/C2 transarticular screw fixation provides a viable method for spinal stabilization in this region. In addition, stabilization can result in resolution of inflammatory pannus formation secondary to instability of the C1/C2 articulation. 相似文献