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81.
There is a deficit of literature regarding the association between nickel allergy–induced symptoms and implanted devices. This report describes a case of nickel allergy causing debilitating migraine-like symptoms, failing to resolve with medical therapy, requiring surgical removal of the device and repair of the defect.  相似文献   
82.
Inactivating mutations in human ecto-nucleotide pyrophosphatase/phosphodiesterase-1 (ENPP1) may result in early-onset osteoporosis (EOOP) in haploinsufficiency and autosomal recessive hypophosphatemic rickets (ARHR2) in homozygous deficiency. ARHR2 patients are frequently treated with phosphate supplementation to ameliorate the rachitic phenotype, but elevating plasma phosphorus concentrations in ARHR2 patients may increase the risk of ectopic calcification without increasing bone mass. To assess the risks and efficacy of conventional ARHR2 therapy, we performed comprehensive evaluations of ARHR2 patients at two academic medical centers and compared their skeletal and renal phenotypes with ENPP1-deficient Enpp1asj/asj mice on an acceleration diet containing high phosphate treated with recombinant murine Enpp1-Fc. ARHR2 patients treated with conventional therapy demonstrated improvements in rickets, but all adults and one adolescent analyzed continued to exhibit low bone mineral density (BMD). In addition, conventional therapy was associated with the development of medullary nephrocalcinosis in half of the treated patients. Similar to Enpp1asj/asj mice on normal chow and to patients with mono- and biallelic ENPP1 mutations, 5-week-old Enpp1asj/asj mice on the high-phosphate diet exhibited lower trabecular bone mass, reduced cortical bone mass, and greater bone fragility. Treating the Enpp1asj/asj mice with recombinant Enpp1-Fc protein between weeks 2 and 5 normalized trabecular bone mass, normalized or improved bone biomechanical properties, and prevented the development of nephrocalcinosis and renal failure. The data suggest that conventional ARHR2 therapy does not address low BMD inherent in ENPP1 deficiency, and that ENPP1 enzyme replacement may be effective for correcting low bone mass in ARHR2 patients without increasing the risk of nephrocalcinosis. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
83.
Notfall + Rettungsmedizin - In den letzten Jahren hat sich die mechanische Thrombektomie mit Stent-Retrievern als wichtiger Bestandteil der Behandlung des ischämischen Schlaganfalls etabliert....  相似文献   
84.
85.
The article presents a cost-benefit analysis of amniocentesis for detection of chromosomal anomalies based on data (1985/87) collected in the Marseille area. In this geographic area, it is possible to confront, in an exhaustive manner, pregnant women's access to amniocentesis and incidence of fetal anomalies due to chromosomal aberrations. Results show that prenatal diagnosis is highly cost-beneficial, the average cost of one "avoided" case of Down's syndrome being lower than the lifelong costs of care for such a child. However, the study emphasizes that the cost-benefit ratio is highly sensitive to the implicit value society affects to the loss of "normal" fetuses through spontaneous abortions provoked by amniocentesis and because of terminations of pregnancy following diagnosis of minor fetal anomalies. The study also shows that lowering maternal age limit for access to free-of-charge amniocentesis from the current 38 years of age to 35 would have been cost-beneficial. Such lowering of the maternal age limit is discussed and compared with other indications which might be used for systematic access to amniocentesis.  相似文献   
86.
Summary A pharmacokinetic study of randomised crossover design was carried out in which eight patients with recurrent stage pTa or pT1 transitional cell carcinoma of the bladder were given thio TEPA (30 mg) in distilled water or in 10% (v/v) Tween 80 (30 ml) intravesically for 2 h, followed 3 months later by the alternative treatment. Thio TEPA and its primary metabolite, TEPA, were measured in plasma and urine using a sensitive and specific chromatographic assay. Large differences between patients were observed in the proportion of thio TEPA absorbed, ranging from 20%–78%. Peak plasma levels of thio TEPA were observed within 1 h of intravesical administration. By 2 h after administration the plasma levels of TEPA were similar to those of thio TEPA and, in contrast to those of the parent compound, remained at a similar level over the next 4 h. The rate of absorption of thio TEPA was not influenced by Tween 80, but it did cause statistically significant increases in mean peak plasma levels (from 101 to 154 ng/ml) and mean AUC values (from 0.376 to 0.496 g h per ml) and a decrease in the mean half-life (from 1.83 to 1.25 h). To obtain plasma levels similar to those achieved after instillation with thio TEPA alone, the dose should be reduced with Tween 80.  相似文献   
87.
88.
The present report describes a novel rhythmically active brainstem slice preparation that generates respiratory activity spontaneously in both mice and rats of varying maturational states. The brainstems of neonatal (0–4 days) and mature (3–8 weeks) mice and rats were isolated and a 600- to 750-m thick slice cut to include the dorsomedial and the ventrolateral regions of the complete rostro-caudal extent of the medulla. This plane of section we have termed tilted-sagittal. Rhythmically discharging neurones were recorded extracellularly from both the dorsal and ventral regions of the slice. The recording sites of these neurones were found in the hypoglossal motonucleus (XII) and in areas of the ventrolateral medulla that includes the ventral respiratory group (VRG) region. Histological examination revealed the preservation of neuronal structures important for cardiorespiratory regulation and reflex control including the nucleus of the solitary tract as well as the nucleus ambiguus. In addition, pontine structures including the A5 region were also preserved. Rhythmic activity was found only in slices where the ambiguual column was preserved in its entirety. The mean frequency of discharge of XII neurones was 20 and 10 bursts per minute in neonates and mature rodents respectively. In preparations of mature animals we demonstrate that this frequency increased significantly (P<0.05) by either raising temperature from 29°C to 38°C (54%), elevating extracellular potassium concentration from 4 to 7.5 mM (52%), blocking potassium channels (20%) or decreasing pH from 7.4 to 7.0 (18%). The burst duration to frequency ratio of XII and VRG rhythmic neurones was similar and therefore indicative of a common brainstem oscillator. Consistent with this finding was that rhythmic activity in the VRG persisted despite removal of the dorsomedial region of the slice. In contrast, rhythmic XII neurones became tonic following mechanical disconnection of the VRG.  相似文献   
89.
Methods of assessing occupational exposure to diesel exhaust were evaluated in a railroad work environment. The American Conference of Governmental Industrial Hygienists (ACGIH)-recommended elemental carbon and respirable combustible dust methods of sampling and analysis for assessing diesel exhaust were included in the study. A total of 215 personal and area samples were collected using both size-selective (nylon cyclone and Marple) and non-size-selective samplers. The results demonstrate that the elemental carbon method is suitable for the railroad environment and the respirable combustible dust method is not. All elemental carbon concentrations measured were below the proposed ACGIH Threshold Limit Value (TLV) of 0.15 mg/m3. The concentrations of oxides of nitrogen (nitric oxide and nitrogen dioxide) were also found to be below their respective TLVs. There is no correlation between elemental carbon or respirable combustible dust and the oxides of nitrogen. The elemental carbon as fraction of total carbon is about 13 percent, except for onboard locomotives where it is about 24 percent. Comparison of elemental carbon and respirable combustible dust measurements showed consistent relationships for most sampling locations, with respirable combustible dust concentrations 12 to 53 times higher than the elemental carbon levels.  相似文献   
90.
Secretory breast carcinoma is a rare tumor originally described in children and adolescent women with a characteristic morphology and a controversial choice of treatment. We report an additional case of a 4-year-old girl with a breast tumor diagnosed as a secretory carcinoma without involvement of the axillary lymph nodes. The therapy consisted of simple mastectomy and low axillary dissection. She presented with a local recurrence near the surgical scar 8 months later, and a wide elliptical excision of the scar and underlying tissue was performed with subsequent radiotherapy of the surgical bed. This tumor has a relatively benign behavior and rarely metastasizes. A literature review revealed only 22 cases of breast carcinoma in childhood and adolescence. ▪  相似文献   
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