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1.
Abstract: A child had cerebral palsy and linear and whorled nevoid hypermelanosis on the right side of his body. He had spasticity and wasting in both lower limbs, with electroencephalographic changes and brain abnormalities on computerized tomographic scan. Chromosomal study of peripheral blood leukocytes found a normal male karyotype. The pathogenesis of this condition is still unclear.  相似文献   
2.
The real part of the relative permittivity ?′r of some cellulosic materials contaminated with commercial impurities and NaCl (determined as weight percent ash contents), and that of the purified fibres, as well as their hydrolysed residues, free of such contaminations, was measured in the frequency range 102 Hz ≤ f ≤ 105 Hz and in the temperature range 283,15 K ≤ T ≤ 333,15 K. Additional measurements of the imaginary part of relative permittivity ?″r have been carried out in the same frequency and temperature ranges for hydrocellulose samples free of inorganic impurities and contaminated with NaCl. The results obtained show that the variation with temperature of the relative permittivity of the samples examined exhibits a change in slope in the vicinity of 303,15 K except for hydrocellulose samples free of impurities. They further show that the presence of inorganic contaminations has a significant effect on the magnitude of the relative permittivity and its variation with temperature, particularly at low frequency. In the case of samples contaminated with inorganic impurities, interfacial polarization is responsible for the anomalous dielectric behaviour observed with the examined samples.  相似文献   
3.
Cytogenetic analysis of a thymoma showed the presence of a ring chromosome 6 as the sole chromosome abnormality. © 1993 Wiley-Liss, Inc.  相似文献   
4.
5.
Head and neck squamous cell carcinoma (HNSCC) is a common malignancy that continues to be difficult to treat and cure. In many organ systems and tumor types, there have been significant advances in the understanding of the molecular basis for tumorigenesis, disease progression and genetic implications for therapeutics. Although tumorigenesis pathways and the molecular etiologies of HNSCC have been extensively studied, there are still very few diagnostic clinical applications used in practice today. This review discusses current clinically applicable molecular markers, including viral detection of Epstein–Barr virus and human papillomavirus, and molecular targets that are used in diagnosis and management of HNSCC. The common oncogenes EGFR, RAS, CCND1, BRAF, and PIK3CA and tumor suppressor genes p53, CDKN2A and NOTCH are discussed for their associations with HNSCC. Discussion of markers with potential future applications is also included, with a focus on molecular alterations associated with targeted therapy resistance.  相似文献   
6.
This prospective randomized controlled pilot trial was designed to evaluate whether prescreening embryos for aneuploidy can improve clinical outcomes in infertile patients undergoing IVF, without limiting to poor prognosis patients. Although there was no statistically significant improvement in live birth rates or implantation rates in this pilot study, there was a trend toward improved clinical outcomes, indicating that future multicenter randomized trials are needed.  相似文献   
7.
Study ObjectivesConventional metrics of sleep quantity/depth have serious shortcomings. Odds-Ratio-Product (ORP) is a continuous metric of sleep depth ranging from 0 (very deep sleep) to 2.5 (full-wakefulness). We describe an ORP-based approach that provides information on sleep disorders not apparent from traditional metrics.MethodsWe analyzed records from the Sleep-Heart-Health-Study and a study of performance deficit following sleep deprivation. ORP of all 30-second epochs in each PSG and percent of epochs in each decile of ORPs range were calculated. Percentage of epochs in deep sleep (ORP < 0.50) and in full-wakefulness (ORP > 2.25) were each assigned a rank, 1–3, representing first and second digits, respectively, of nine distinct types (“1,1”, “1,2” … ”3,3”). Prevalence of each type in clinical groups and their associations with demographics, sleepiness (Epworth-Sleepiness-Scale, ESS) and quality of life (QOL; Short-Form-Health-Survey-36) were determined.ResultsThree types (“1,1”, “1,2”, “1,3”) were prevalent in OSA and were associated with reduced QOL. Two (“1,3” and “2,3”) were prevalent in insomnia with short-sleep-duration (insomnia-SSD), but only “1,3” was associated with poor sleep depth and reduced QOL, suggesting two phenotypes in insomnia-SSD. ESS was high in types “1,1” and “1,2”, and low in “1,3” and “2,3”. Prevalence of some types increased with age while in others it decreased. Other types were either rare (“1,1” and “3,3”) or high (“2,2”) at all ages.ConclusionsThe proposed ORP histogram offers specific and unique information on the underlying neurophysiological characteristics of sleep disorders not captured by routine metrics, with potential of advancing diagnosis and management of these disorders.  相似文献   
8.
Helicobacter pylori (H. pylori) are pathogenic bacteria that infect a half of the human population, colonize gastric mucosa and can be found in gastric juice. Reflux of gastric juice has been suggested to be associated with glue ear in children. It has been suggested that tonsil and adenoid tissues are potential reservoirs of H. pylori infection. These observations raise the question as to whether H. pylori infection might have a role in otitis media with effusion (OME) in children. The objectives of this research were to evaluate the incidence and possible role of H. pylori in the pathogenesis of OME in children and to evaluate the clarithromycin-resistant strains. Molecular assessment was done to evaluate the culture results vs. molecular study. A total of 60 children, who were prone to ventilation tube insertion, adenoidectomy and/or tonsillectomy were included in the study. The control group consisted of 40 children who underwent adenoidectomy and/or tonsillectomy without the history of OME. Samples of the middle ear fluid and mucosa, adenoid tissue, tonsillar tissue and gastric lavage were cultured and underwent polymerase chain reaction (PCR) analysis then were assembled by using QIAxcel System as capillary electrophoresis for H. pylori detection. There was significant difference between the results of cultures and PCR (P < 0.05). Middle ear fluid culture was positive for H. pylori in 40% of the patients vs. 56.7% PCR results while middle ear mucosa culture was positive in 20% vs. 26.7% PCR results. Gastric lavage culture was positive in 46.6% of the patients and PCR was positive in 63.3% of the patients. Adenoid culture and PCR were positive in 56.3% for each, while tonsil culture was positive in 70% and PCR was positive in 90%. H. pylori presence in the gastric lavage, the tonsillar and adenoid tissues by culture and PCR was significantly more frequent in the study group compared to the control group. The minimum inhibitory concentration (MIC) values of clarithromycin-resistant isolates ranged from 1.5 to 8 μg/ml. This study showed the presence of H. pylori in around 50% of the patients with OME. PCR revealed its sensitivity than culture techniques. The incidence of clarithromycin resistance was found to be high among the isolates (39.6%).  相似文献   
9.
目的:使用光谱域光学相干断层成像(SD-OCT)技术研究中心性浆液性脉络膜视网膜病变(CSCR)3mo后脉络膜厚度的变化。方法:前瞻性研究。共纳入60眼,20眼(平均年龄:33.65±5.24岁)典型急性单侧中心性浆液性脉络膜视网膜病变以及对侧正常眼,20眼为健康对照组。进行荧光素血管造影和OCT检查。测量中心凹下脉络膜厚度(SFCT),黄斑中心凹视网膜厚度(CMT),到中央凹和视网膜下液1000μm处颞部和鼻部。结果:在三个不同的位置,三组间的SFCT差异有统计学意义。中心性浆液性脉络膜视网膜病变眼中心凹下脉络膜厚度(372.40±34.39μm)在基线和随访3mo后均显著大于对侧正常眼(302.10±8.9μm)和对照组眼(279.80±14.49μm)。CSCR眼平均CMT为317±141.86μm,并且SFCT与CMT呈显著正相关。结论:不同部位脉络膜厚度的增加,以及被称为“厚脉络膜”的过度扩张和高渗透血管,似乎在包括中心性浆液性脉络膜视网膜病变在内的广泛疾病中起着重要作用。  相似文献   
10.

Aim/Background

How the gubernaculum guides the testis into the scrotum remains controversial, with various proposals from passive inversion to active growth. We aimed to determine if the gubernaculum contains an area of active proliferation, such as a “progress zone” in a growing embryonic limb bud, using a fluorescent cell membrane marker, 1,1′-didodecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate [DiIC12(3)], to trace cell migration, and 5-bromodeoxyuridine (BUDR) (a thymidine analogue) as a mitotic marker.

Methods

Gubernacula were collected from neonatal male rats (n = 42, day 1-2, Sprague-Dawley) and cultured with calcitonin gene-related peptide (CGRP; 714 nmol/L). 1,1′-didodecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate-coated glass beads (diameter, 150-212 μm) were placed next to the bulb for the first 3 hours. Gubernacula were cultured for 3, 18, and 24 hours, then frozen sections cut and examined by confocal microscopy (wavelength, 549 nm). In a second experiment, pups not exposed to exogenous CGRP (n = 53, day 0, Sprague-Dawley) were injected intraperitoneally with BUDR (50 mg/kg of body weight); gubernacula were collected at 2, 48, 72, and 96 hours postinjection (PI), sectioned, and stained using immunohistochemistry to count the number of BUDR-positive cells per 100 cells (labeling index) in the bulb, cremaster, cord, and epididymis.

Results

After 24 hours' culture with CGRP, the bulb showed an oval region (diameter, 300 μm) of high fluorescence, and the cremaster region showed elongated cells migrating out of the bulb. When cultured without CGRP, the same oval region contained no fluorescence. In vivo BUDR labeling index increased in all areas until 48 hours postinjection and then decreased most rapidly in the bulb (P < .05), in the presence of endogenous CGRP from the genitofemoral nerve.

Conclusions

The rat gubernaculum contains a putative progress zone, such as in a growing limb bud, in the presence of CGRP. Cells migrate out of this zone to form cremaster muscle. We hypothesize that proliferation in the bulb elongates the gubernaculum, whereas proliferation of cremaster cells would increase gubernacular diameter. This brings to “life” the gubernaculum as an actively growing organ in contrast to the inert ligament connecting the testis to the scrotum portrayed in most anatomy textbooks.  相似文献   
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