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211.
One hundred infants with intracranial tumors symptomatic during the 1st year of life were studied. They differed from older children in having a higher percentage of supratentorial tumors and in the fact that 90% of the tumors were of neuroectodermal origin. Vomiting, alteration of psychomotor development, and macrocrania were the most common presenting features. The "diencephalic syndrome" was seen in 5 infants, and subarachnoid hemorrhage due to tumor was diagnosed in 4. Computed tomography as the primary investigation is increasing the number of neoplasms diagnosed in this age group, although review of the skull roentgenograms in the series disclosed an abnormality in 92%. Eighty of the tumors were verified, 68 by a cranial operation and the rest at autopsy. Of the verified neoplasms, 20% were medulloblastomas, 12.5% were choroid plexus papillomas, and 10% were cerebellar astrocytomas. The cumulative average survival was 27 months but, for those who underwent a tumor operation, the average survival was 37 months. The operative mortality was 30%. Thirty-nine patients were irradiated, and this subset had a 5-year survival rate of 43%. The morbidity was high irrespective of radiotherapy; 60% of those who survived 1 year were moderately or severely disabled. Those infants receiving more than 5000 rads of whole brain radiation tended to have greater deficits in the long term. When analyzed separately, patients treated after 1970 had greatly improved mortality and morbidity rates.  相似文献   
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The beta-adrenoceptor antagonist Timolol Maleate (0.5%) was employed topically to determine whether the resting (or "tonic") position of accommodation is a consequence of steady-state equilibrium between parasympathetic and sympathetic innervation of the ciliary muscle. Ten subjects were used, eight men and two women, with an age range of 19-37 (mean = 23.2). All subjects wore an optimum refractive correction giving visual acuities of 20/20 or better. Darkroom measurements of tonic accommodation (TA), tonic vergence (TV), and pupil diameter were determined with a Badal laser optometer , a nonius alignment device and infra-red photography, respectively. Far and near points of accommodation and oculo-motor balance tests were determined by standard optometric techniques and intraocular pressure (IOP) was measured by applanation tonometry. Both TA (mean = 1.66 D) and TV (mean = 2.10 deg) assumed intermediate resting positions in the absence of visual stimulation. A double-blind protocol between Timolol and Saline demonstrated a mean myopic shift in TA of +0.85 D over 40 min with Timolol. All other experimental parameters, apart from IOP, were unaffected by Timolol. It is concluded that sympathetic innervation to the ciliary muscle plays a significant role in determining the TA position and that this innervation is mediated by inhibitory beta adrenoceptors.  相似文献   
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We developed an assay that detects minus-strand RNA as a surrogate for actively replicating severe acute respiratory syndrome coronavirus 2. We detected minus-strand RNA in 41 persons with coronavirus disease up to 30 days after symptom onset. This assay might inform clinical decision-making about patient infectiousness.  相似文献   
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IntroductionReoperative parathyroidectomy for persistent and recurrent primary hyperparathyroidism is dependent on radiology. This study aimed to compare outcomes in reoperative parathyroidectomy at a single centre using a combination of traditional and newer imaging studies.Materials and methodsRetrospective case note review of all reoperative parathyroidectomies for persistent and recurrent primary hyperparathyroidism over five years (June 2014 to June 2019; group A). Imaging modalities used and their positive predictive value, complications and cure rates were compared with a published dataset spanning the preceding nine years (group B).ResultsFrom over 2000 parathyroidectomies, 147 were reoperations (101 in group A and 46 in group B). Age and sex ratios were similar (56 vs 62 years; 77% vs 72% female). Ultrasound use remains high and shows better positive predictive value (76% vs 57 %). 99mTc-sestamibi use has declined (79% vs 91%) but the positive predictive value has improved (74% vs 53%). 4DCT use has almost doubled (61% vs 37%) with better positive predictive value (88% vs 75%). 18F-fluorocholine positron emission tomography-computed tomography and ultrasound-guided fine-needle aspiration for parathyroid hormone are novel modalities only available for group A. Both carried a positive predictive value of 100%. Venous sampling with or without angiography use has decreased (35% vs 39%) but maintains a high positive predictive value (86% vs 91%). Cure rates were similar (96% vs 100%). Group A had 5% permanent hypoparathyroidism, 1% permanent vocal cord palsy and 1% haematoma requiring reoperation. No complications for group B.ConclusionOptimal imaging is key to good cure rates in reoperative parathyroidectomy. High-quality, non-interventional imaging techniques have produced a shift in the preoperative algorithm without compromising outcomes.  相似文献   
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BackgroundPrior studies have demonstrated declines in androgen levels in men with cancer and patients undergoing anesthesia and surgery. In this study, we hypothesized that decreased serum androgen levels are prevalent in male patients undergoing radical cystectomy (RC) for bladder cancer and that it persists in the postoperative period. We characterized perioperative androgen hormonal profiles and examined for associated changes indicative of sarcopenia on computed tomography scans in men undergoing RC.MethodsWe implemented a prospective observational trial in men with newly diagnosed non-metastatic bladder cancer undergoing RC. Baseline pre-operative total testosterone (TT), free testosterone (FT), and luteinizing hormone (LH) were obtained on morning lab draws with 30 days of surgery. TT and FT were then repeated on postoperative days (POD) 2, 3, 30, and 90. The threshold for normal TT was defined as >300 ng/dl, consistent with the AUA Guidelines for Evaluation and Management of Testosterone Deficiency. We evaluated postoperative changes in weight and psoas muscle cross-sectional area using computed tomography scans to assess for sarcopenic changes.ResultsUnivariable statistical analysis was performed. 25 patients were enrolled. The mean patient age was 68.9 years. The mean pre-operative TT was 308 ng/dl, and 12/23 (52.5%) patients had low testosterone. Mean TT onPOD 2 and 3 were 166 ng/dl and 161 ng/dl, respectively (range 24–345). 19/20 (95%) of men who had morning lab draws had decreased TT. The mean TT at 30 days was 253 ng/dl with 37.5% of men having low TT. Mean TT at 90 days was 306 ng/dl. The mean FT levels were 43 ng/dl, 29.25 ng/dl, 28.2 ng/dl, 40.89 ng/dl, and 42.62 ng/dl at baseline, POD 2, POD 3, POD 30, and POD 90, respectively. Mean LH at baseline was 9.9 IU/L. Average weight loss at 30- and 90- days postop was -4.29 and -4.38 kilograms, respectively. Weight loss was persistent with only 3/23 (13%) returning to their presurgery weight by 90 days. Despite significant declines in weight and perioperative TT, no significant differences in psoas muscle cross-sectional area were observed (net change -92 mm2, P= 0.13)ConclusionsPerioperative disruption of androgen levels is prevalent in men undergoing RC. Our trial demonstrates a pre-op, immediate postop, 30- and 90-day postoperative prevalence of low TT of 52%, 95%, 63%, and 37.5%, respectively. Significant changes in baseline weight were noted, although no significant changes in psoas muscle cross-sectional area were observed, limiting conclusions regarding a link between changes in androgens and sarcopenia in this setting.  相似文献   
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