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91.
Viral infections have already been implicated with otitis media and sudden sensorineural hearing loss. However, the pathophysiology of COVID-19 as it relates to otologic disorders is not well-defined. With the spread of SARS-CoV-2, it is important to evaluate its colonization of middle ear mucosa. Middle ear and nasal tissue samples for quantitative RT-PCR and histologic evaluations were obtained from post-mortem COVID-19 patients and non-diseased control patients. Here we present evidence that SARS-CoV-2 colonizes the middle ear epithelium and co-localizes with the primary viral receptor, angiotensin-converting enzyme 2 (ACE2). Both middle ear and nasal epithelial cells show relatively high expression of ACE2, required for SARS-CoV-2 entry. The epithelial cell adhesion molecule (EpCAM) was use as a biomarker of epithelia. Furthermore, we found that the viral load in the middle ear is lower than that present in the nasal cavity.  相似文献   
92.
Patients with drug-resistant epilepsy (DRE) rarely achieve seizure freedom with medical therapy alone. Despite being safe and effective for select patients with DRE, epilepsy surgery remains heavily underutilized. Multiple studies have indicated that the overall rates of surgery in patients with DRE have stagnated in recent years and may be decreasing, even when hospitalizations for epilepsy-related problems are on the rise. Ultimately, many patients with DRE who might otherwise benefit from surgery continue to have intractable seizures, lacking access to the full spectrum of available treatment options. In this article, we review the various factors accounting for the persistent underutilization of epilepsy surgery and uncover several key themes, including the persistent knowledge gap among physicians in identifying potential surgical candidates, lack of coordinated patient care, patient misconceptions of surgery, and socioeconomic disparities impeding access to care. Moreover, factors such as the cost and complexity of the preoperative evaluation, a lack of federal resource allocation for the research of surgical therapies for epilepsy, and difficulties recruiting patients to clinical trials all contribute to this multifaceted dilemma.  相似文献   
93.
94.
BACKGROUND: No information exists in the literature regarding the factors affecting the blood flow towards the endometrial and subendometrial regions during IVF treatment. METHODS: We examined the effect of women's age, their smoking habits, their type of infertility (i.e. primary or secondary) and parity, causes of infertility and serum estradiol (E2) concentration on endometrial and subendometrial blood flows as measured by a three-dimensional (3D) power Doppler ultrasound during IVF treatment. All patients received a standard long protocol of ovarian stimulation and serum E2 concentration was determined on the day of hCG. 3D ultrasound examination with power Doppler was performed on the day of oocyte collection to determine vascularization index (VI), flow index (FI) and vascularization flow index (VFI) of endometrial and subendometrial regions. RESULTS: The age of women, their smoking habits, their types of infertility and parity and causes of infertility had no effect on the endometrial and subendometrial 3D power Doppler flow indices. There was a negative correlation between serum E(2) concentration and endometrial FI (r = -0.109; P = 0.006). CONCLUSIONS: Endometrial blood flow in IVF treatment was negatively affected by serum E2 concentration only.  相似文献   
95.
Background  Similar to other99mTc-based infarct-avid agents,99mTc-glucarate localizes in myocardial infarcts. Whether severely ischemic viable myocytes sequester99mTc-glucarate is uncertain. To assess the infarct specificity, in vitro and in vivo studies were performed. Methods and Results  H9C2 embryonic rat cardiocytes cultured under normoxia (N) or hypoxia (H) for 24 hours in 7.5 μCi99mTc-glucarate were compared with necrotic cardiocytes. Mean H/N ratio (3.0±0.004, mean±SD) was significantly less than that of the necrotic/N ratio (39.9±6.5,p<0.01). Reperfused myocardial infarction (MI) in 4 dogs confirmed by201Tl, (0.5 to 1.0 mCi) scintigraphy were imaged serially, with simultaneously injected mixture of99mTc-glucarate and111In-antimyosin Fab. Infarcts were detected scintigraphically within 4 to 10 minutes with99mTc-glucarate.111In-antimyosin required more than 1 hour. Myocardial distribution at 5 hours showed a direct correlation between99mTc-glucarate and111In-antimyosin uptake (r=0.99,p<0.0001). Both99mTc-glucarate (r=−0.777,p<0.0001) and111In-antimyosin (r=−0.775,p<0.0001) were inversely related to201Tl distribution. Conclusions  The near perfect correlation between99mTc-glucarate and111In-antimyosin uptake (r=0.99) in reperfused canine MI and the insignificant glucarate uptake by viable cardiocytes in vitro attest to the avidity of99mTc-glucarate for the necrotic myocardium and favor its use as a specific early marker of myocyte necrosis in acute MI. Supported in part by SBIR grant 1R43-HL54410-01 and Molecular Targeting Technology, Inc.  相似文献   
96.
We herein report a rare case of extraosseous calcifying epithelial odontogenic tumor with local aggressive behavior. CT and MR imaging showed the distinctive appearances of this histologic entity. We briefly discuss the radiologic features of calcifying epithelial odontogenic tumor and the relevant literature.  相似文献   
97.
ObjectiveTo evaluate the performance of the StatStrip? glucose meter from Nova Biomedical for use in complex tertiary care facilities.MethodsPerformance evaluation was conducted in 6 clinical locations involving nurse end-users. Imprecision (CV) < 5% was considered acceptable. Ten substances were examined for potential analytical interferences at two levels and 3 glucose concentrations. Inaccuracy was determined by 386 paired glucose differences between glucose meter and laboratory reference analyses. Acceptability was based on CSLI/ISO15197 criteria. Potential clinical impact was classified under a 5-level severity scheme.ResultsImprecision varied from CV 2.4 to 4.9%. Significant interference was observed only for free hemoglobin at 10 g/L. 97% of paired glucose meter-laboratory differences met CSLI/ISO15197 criteria. All discrepant results had low severity scores.ConclusionThe StatStrip? glucose meter demonstrated acceptable imprecision and inaccuracy, and was relatively free from common interferences. It should be a good candidate for general use in complex tertiary care facilities.  相似文献   
98.
Glucose-6-phosphate dehydrogenase (G6PD)-deficient subjects are susceptible to chemical-induced oxidative haemolysis. Little is known concerning the haemolytic properties of Chinese herbal medicine on G6PD-deficient subjects. Our objective was to investigate the pro-oxidative effect of 18 commonly used Chinese herbal medicine (CHM) on human G6PD-deficient red blood cells. G6PD-deficient (n=10) and normal (n=10) whole blood samples were incubated with water extracts of CHM. The resulting levels of reduced glutathione (GSH) and methaemoglobin (MetHb) were determined by biochemical assays. Rhizoma Coptidis significantly reduced GSH level by 48.9+/-5.4% (at 1 mg/mL) in the G6PD-deficient erythrocytes (P<0.001) compared with the respective control group without challenge. Similar dose-dependent responses were observed at higher concentrations of Cortex Moutan, Radix Rehmanniae, Radix Bupleuri, Rhizoma Polygoni Cuspidati and Flos Chimonanthi (P<0.01, 5-10 mg/mL). In addition, the levels of MetHb were elevated significantly when challenged with Rhizoma Coptidis (2.8 fold at 5 mg/mL) and Cortex Moutan (3.4 fold at 10 mg/mL). This is the first report on the pro-oxidative action of CHM on G6PD-deficient blood samples in vitro as demonstrated by the decrease of GSH and increase of MetHb. G6PD-deficient subjects should restrain from excessive consumption of these pro-oxidative herbs.  相似文献   
99.
The "absolute safety" of bromocriptine as a drug of choice in suppression of lactation is questioned. Two cases of cerebrovascular events after the use of bromocriptine for lactation suppression are presented, and the available, pertinent literature is reviewed.  相似文献   
100.
BACKGROUND AND PURPOSE: Nicotinamide protects against brain damage in ischemia-reperfusion. However, the dosage and time of treatment require clarification. It is also not clear if nicotinamide can protect against both necrosis and apoptosis. METHODS: Dose-response and time-effect studies were designed. Transient focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) for 90 min. Different doses of nicotinamide were injected upon reperfusion. In time-effect studies, 500 mg/kg nicotinamide was administered at different times after the onset of reperfusion. Neurological finding scores were recorded. Infarct volumes were measured. RESULTS: In contrast to controls, neurological deficit scores and infarct volumes were greatly reduced by treatment with nicotinamide. The ED(50) of nicotinamide was 239+/-79 mg/kg (P=.95). It was found that nicotinamide injected during the first 6 h of reperfusion could effectively inhibit the development of brain damage. The optimal dose of nicotinamide was 500 mg/kg and gave a maximal response. CONCLUSIONS: Poly(ADP-ribose) polymerase (PARP) plays a key role in DNA repair in stroke. Excessive PARP activity consumes NAD leading to energy depletion and neuronal damage. As an inhibitor of PARP, nicotinamide promotes the supply of energy. The results suggest that early application of nicotinamide at a suitable dosage significantly ameliorates necrotic and apoptotic brain injury after focal ischemia-reperfusion.  相似文献   
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