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351.
This study aimed to assess the magnetic resonance (MRI) features of the superior cervical ganglion (SCG) and to track changes to it induced using radiotherapy across a long-term follow-up. In total, 75 patients who underwent radiotherapy for head and neck malignancies and who were studied with MRI were recruited from two centers. MRI was performed before and after radiotherapy, with a median long-term follow-up of 4.5 years. Baseline SCG features were assessed. Changes in axial cross-sectional area, T2-normalized signal, and apparent diffusion coefficient (ADC) (the latter available in about half of the patients) were analyzed. Repeated measures analysis of variance with Bonferroni’s correction was used to analyze changes in the aforementioned parameters (significance level 0.05). Out of a potential 149 SCGs, 136 were visible at baseline MRI. A variable spatial relationship with the internal carotid artery was found. SCGs showed the “black dot” sign in almost all of the patients. ADC was higher in SCGs than in regional lymph nodes. Cross-sectional area, normalized T2, and ADC increased in the period up to 1 year after radiotherapy and then remained stable in subsequent longer-term follow-up. The SCG has unusual features that allow differentiation from the regional lymph nodes. Changes in morphology and signal after radiotherapy must be taken into account by radiologists to avoid misdiagnosis as recurrent nodal disease. Changes induced using radiotherapy are stable in long-term follow-up and are thus likely attributed to other factors (such as Schwann cell hypertrophy/proliferation) rather than edema.  相似文献   
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Tiong JD  Pakiam JG  Wray S 《Endocrinology》2004,145(8):3608-3612
GnRH-1 is a decapeptide hormone that regulates gonadal maturation and fertility. In brain, GnRH-1 is secreted by neurons residing mainly in the preoptic/hypothalamic area. These neurons arise from cells in the nasal placode during embryonic development. GnRH-1 mRNA and peptide in the nonhypothalamic region have been described, suggesting other functions of GnRH-1. This paper describes for the first time the expression of GnRH-1 in developing incisors in mice. At embryonic day (E) 12.5, GnRH-1 mRNA and peptide were localized in cells in oral and dental epithelia. At postnatal day (P) 6, before incisor eruption, GnRH-1 was expressed in cells in dental epithelial-derived structures that include the papillary layer, outer dental epithelium, stellate reticulum, stratum intermedium, and enamel-secreting ameloblast cell layer. GnRH-1 expression correlated with cell maturity, becoming stronger in cells farther away from the proliferative zone. From E12.5 through P6, GnRH-1 expression was not detected in neural crest-derived dental mesenchyme or in mesenchyme-derived structures that include dental papilla, dental follicle, and dentin-secreting odontoblast. In addition, GnRH-1 expression was not detected in molars, indicating that expression of GnRH-1 is differentially regulated in incisor vs. molars, with only the former exhibiting continuous growth in this species. In homozygous hypogonadal mice at P1, GnRH-1 peptide expression was not detected, yet incisors were present. However, morphological changes in cells between dental follicle and ameloblast cell layer were noted. Taken together, our results indicate that GnRH-1 expression, although not essential for initiation and formation of incisors, may be important in maturation and/or maintenance of these placodally derived structures.  相似文献   
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The objectives of this study are to compare steady-state trough (Cmin,ss) and peak (Cmax,ss) concentrations of rivaroxaban between Asians and Caucasians and to evaluate the relationship between rivaroxaban concentrations and prothrombin time/international normalized ratio (PT/INR). Recruited patients were advised on the time to take rivaroxaban. Cmin,ss and PT/INR were taken when patients arrived. Cmax,ss and PT/INR were drawn between 2 and 4 h later after the patient took rivaroxaban with food. Thirty patients were included in the analyses: 57% (n?=?17) males and 43% (n?=?13) females, 77% (n?=?23) on 20 mg and 23% (n?=?7) on 15 mg. Median PTtrough and PTpeak are moderately correlated with Cmin,ss (r2?=?0.43) and Cmax,ss (r2?=?0.49), respectively. Patients on 15 mg have lower Cmin,ss and Cmax,ss versus Caucasians [12 ng/ml vs. 57 ng/ml (Cmin,ss); 87 ng/ml vs. 229 ng/ml (Cmax,ss), p?<?0.01 for both]. Patients on 20 mg also have lower Cmin,ss and Cmax,ss versus Caucasians [14 ng/ml vs. 44 ng/ml (Cmin,ss); 101 ng/ml vs. 249 ng/ml (Cmax,ss), p?<?0.01 for both]. Subgroup analysis shows patients with BMI?≥?30 have lower Cmax,ss than patients with BMI?<?30 [80.47 ng/ml vs. 124 (p?=?0.014)]. Cmin,ss and Cmax,ss were lower in Singaporeans than Caucasians. This may have an impact on the effectiveness of rivaroxaban in Singaporeans. Patients with higher BMI may not benefit similarly as patients with lower BMI. Lastly, the Dade Innovin reagent’s measure of PT/INR is not sensitive towards changes in rivaroxaban concentrations.  相似文献   
356.

Background

The LMA Supreme? (SLMA) is a single-use supraglottic device that provides a good seal for positive pressure ventilation. It has a double aperture design that facilitates the introduction of an orogastric tube to aspirate gastric contents. This observational study evaluated the role of the SLMA in parturients undergoing Cesarean delivery under general anesthesia.

Methods

Non-obese parturients with at least four hours of fasting and antacid prophylaxis scheduled for uncomplicated Cesarean delivery were recruited from June 2009 through May 2010 at the Quanzhou Women??s and Children??s Hospital, China. We recorded the number of SLMA insertion attempts, the time to effective ventilation, the incidence of aspiration, and other anesthetic and obstetric outcomes. Postoperatively, we noted the presence of blood on the SLMA, postoperative sore throat, and patient satisfaction. Analysis included comparison of results between parturients having elective and urgent Cesarean delivery.

Results

We recruited 700 parturients (576 elective, 124 urgent). Mean (standard deviation) body mass index was 25.6 (2.5) kg·m?2. All SLMA insertions were successful, with 686 (98%) inserted on first attempt and a time to effective airway of 19.5 (3.9) sec. We maintained ventilation and oxygenation in all parturients with a good seal and there was no evidence of aspiration. Eighteen parturients (2.6%) had blood on the SLMA upon removal, 24 (3.4%) had sore throat, and patient satisfaction was 85 (7)%. These results were similar in elective and urgent cases.

Conclusions

In a carefully selected group of parturients, the SLMA is a useful alternative to tracheal intubation for Cesarean delivery, providing effective ventilation and a low incidence of side effects or complications.  相似文献   
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358.
A 3.5-week-old male neonate who developed an upper and lower respiratory tract rhinovirus infection that was temporally associated with the development of severe pulmonary hypertension is described. Rhinovirus has not previously been associated with pulmonary hypertension. This child developed severe pulmonary hypertension with right ventricular failure, requiring mechanical ventilation, nitric oxide inhalation and, eventually, extracorporeal membrane oxygenation.  相似文献   
359.
We performed three cases of donor bladder trigone facilitated transplantation using pediatric en bloc kidneys into adult recipients. The donors were aged 11, 21, and 23 months; two of the donors were male, and the other was a female. In each case, the donor bladder was removed and the trigone was fashioned into a patch that contained both ureters, which was attached to the recipient anterior bladder wall. The recipients of the two male donor transplants healed and have normal voiding with no evidence of vesico-ureteral reflux. At 14 and 12 months, they have a creatinine of 1.2 and 1.0 mg/dL. The recipient of the female donor transplant developed a pelvic abscess, which necessitated reconstruction of the donor ureters and patch. She is now nine months with a creatinine of 1.2 mg/dL and voiding well. The use of the donor bladder trigone to facilitate pediatric en bloc transplantation can be carried out safely using the male donor urinary tract. However, the use of a female donor for this procedure may be a special circumstance requiring increased attention to sterilize the small donor introitus and avoiding devascularization of the bladder trigone that is adherent to the anterior vaginal wall.  相似文献   
360.
Missense mutations in the 3' end of the p63 gene are associated with either RHS (Rapp-Hodgkin syndrome) or AEC (Ankyloblepharon Ectodermal defects Cleft lip/palate) syndrome. These mutations give rise to mutant p63alpha protein isoforms with dominant effects towards their wild-type counterparts. Here we report four RHS/AEC-like patients with mutations (p.Gln9fsX23, p.Gln11X, p.Gln16X), that introduce premature termination codons in the N-terminal part of the p63 protein. These mutations appear to be incompatible with the current paradigms of dominant-negative/gain-of-function outcomes for other p63 mutations. Moreover it is difficult to envisage how the remaining small N-terminal polypeptide contributes to a dominant disease mechanism. Primary keratinocytes from a patient containing the p.Gln11X mutation revealed a normal and aberrant p63-related protein that was just slightly smaller than the wild-type p63. We show that the smaller p63 protein is produced by translation re-initiation at the next downstream methionine, causing truncation of a non-canonical transactivation domain in the DeltaN-specific isoforms. Interestingly, this new DeltaDeltaNp63 isoform is also present in the wild-type keratinocytes albeit in small amounts compared with the p.Gln11X patient. These data establish that the p.Gln11X-mutation does not represent a null-allele leading to haploinsufficiency, but instead gives rise to a truncated DeltaNp63 protein with dominant effects. Given the nature of other RHS/AEC-like syndrome mutations, we conclude that these mutations affect only the DeltaNp63alpha isoform and that this disruption is fundamental to explaining the clinical characteristics of these particular ectodermal dysplasia syndromes.  相似文献   
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