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1.
First described in 1955 in New Jersey, epizootic haemorrhagic disease (EHD) causes a severe clinical disease in wild and domestic ruminants worldwide. Epizootic haemorrhagic disease outbreaks occur in deer populations each year from summer to late autumn. The etiological agent is EHD virus (EHDV) which is a double‐stranded segmented icosahedral RNA virus. EHD virus utilizes point mutations and reassortment strategies to maintain viral fitness during infection. In 2018, EHDV serotype 2 was predominantly detected in deer in Illinois. Whole genome sequencing was conducted for two 2018 EHDV2 isolates (IL41747 and IL42218) and the sequence analyses indicated that IL42218 was a reassortant between different serotypes whereas IL41747 was a genetically stable strain. Our data suggest that multiple strains contribute to outbreaks each year.  相似文献   
2.
Intravascular papillary endothelial hyperplasia (IPEH) is an unusual vascular lesion of proliferating endothelial cells. It is more frequently seen in the extremities, particularly in the fingers. Oral IPEH has been reported with the common sites being lip, tongue, and buccal mucosa. In this article, we present a case of oral IPEH of the floor of the mouth, an unusual location, presenting in a 9-month-old male. The histogenesis, histologic features, and ultrastructural features are also reviewed. A misdiagnosis of angiosarcoma can be made in a case of IPEH due to similar histopathologic features. It is imperative to rule out this error by an elaborate histopathologic evaluation ofthese lesions.  相似文献   
3.
BACKGROUND: Habitual arecanut chewing is associated with Oral Submucous Fibrosis (OSF). High copper content in arecanut plays a vital role in pathogenesis of OSF. This study evaluates the copper-staining pattern of buccal epithelial cells in oral cytological smears of non-chewers, chewers, and OSF. MATERIALS & METHODS: Alcohol fixed buccal epithelial smears of 10 histopathologically confirmed cases of OSF, 10 chewers without lesion, and 5 nonchewers were stained with modified Rhodamine technique and studied under the light microscope. Buccal epithelial smears of non-chewers dipped in copper sulphate solution were used as known positive for copper. RESULT: Copper appeared as shades of palered within the cytoplasm of chewers and did not show any stain in non-chewers. Intense red stain was seen in OSF smears as dark granules within the cytoplasm. CONCLUSION: Intense staining of copper in OSF buccal smears, than in the chewers supports the role of copper in the pathogenesis of OSF.  相似文献   
4.
During radiotherapy treatment planning, the margins given to the clinical target volume to form the planning target volume accounts for internal motion and set-up error. Most margin formulas assume that the underlying distributions are independent and normal. Clinical data suggests that the set-up error probability density function (pdf) can be considered to have an approximately normal distribution. However, there is evidence that internal motion does not have a normal distribution. Thus, in general, a convolution of the two pdfs should be performed to determine the total geometric error. The goals of this article were to (1) determine if the internal motion pdf due to respiration can be characterized using a normal distribution, and (2) if not, determine if the total geometric uncertainty for combining internal motion and set-up error can be characterized by a normal distribution. Sixty fluoroscopy diaphragm motion data sets were obtained using three breathing training types: free breathing, audio instruction, and visual feedback. Diaphragm motion was used as a surrogate for liver and lung cancer motion. The data were analyzed with normality tests in the following groups: (1) single motion measurements, (2) combined motion measurements for each patient, and (3) combined motion measurements for all patients. Following this analysis, the diaphragm motion pdfs were convolved with a set-up error pdf, and the standard deviation of the set-up error pdf at which the total geometric error pdf became normal was determined. At set-up error standard deviation values of at least 0.27 and 0.1 cm for free breathing, 0.57 and 0.42 cm for audio instruction, and 0.55 and 0 cm for visual feedback, for single motion measurements and combined motion measurements for each patient, respectively, total geometric error pdfs became approximately normal. When the motion measurements for all the patients were combined, diaphragm motion pdfs were approximately normal for all feedback types. Therefore, for treatment planning purposes in the absence of individual patient measurements, the diaphragm motion pdf can be considered an approximately normal distribution. However, care should be taken when determining a margin based on individual patients measurements as the total geometric error will, in general, not be normally distributed.  相似文献   
5.
On the use of EPID-based implanted marker tracking for 4D radiotherapy   总被引:2,自引:0,他引:2  
Four-dimensional (4D) radiotherapy delivery to dynamically moving tumors requires a real-time signal of the tumor position as a function of time so that the radiation beam can continuously track the tumor during the respiration cycle. The aim of this study was to develop and evaluate an electronic portal imaging device (EPID)-based marker-tracking system that can be used for real-time tumor targeting, or 4D radiotherapy. Three gold cylinders, 3 mm in length and 1 mm in diameter, were implanted in a dynamic lung phantom. The phantom range of motion was 4 cm with a 3-s "breathing" period. EPID image acquisition parameters were modified, allowing image acquisition in 0.1 s. Images of the stationary and moving phantom were acquired. Software was developed to segment automatically the marker positions from the EPID images. Images acquired in 0.1 s displayed higher noise and a lower signal-noise ratio than those obtained using regular (> 1 s) acquisition settings. However, the markers were still clearly visible on the 0.1-s images. The motion of the phantom blurred the images of the markers and further reduced the signal-noise ratio, though they could still be successfully segmented from the images in 10-30 ms of computation time. The positions of gold markers placed in the lung phantom were detected successfully, even for phantom velocities substantially higher than those observed for typical lung tumors. This study shows that using EPID-based marker tracking for 4D radiotherapy is feasible, however, changes in linear accelerator technology and EPID-based image acquisition as well as patient studies are required before this method can be implemented clinically.  相似文献   
6.
Aeromonas spp. and their association with human diarrheal disease.   总被引:9,自引:1,他引:9       下载免费PDF全文
Between January 1988 and December 1989 Aeromonas species were isolated from 45 (1.8%) of 2,480 patients with acute gastroenteritis. No other bacterial enteric pathogens were found in any of these 45 patients. Of the 45 Aeromonas isolates, 35 strains (77.8%) were Aeromonas hydrophila, 7 (15.5%) were Aeromonas sobria, and 3 (6.7%) were Aeromonas caviae. Most of the patients were under 5 years of age. No bacterial enteric pathogens, including Aeromonas species, were isolated from 512 age- and sex-matched control subjects. Examination of the Aeromonas isolates for exotoxin production (enterotoxin and hemolysin) indicated that all strains, irrespective of species, were enterotoxin positive (rabbit ileal loop model) and hemolysin positive (rabbit erythrocyte model). These results suggest that Aeromonas species are potential enteric pathogens in our geographical region.  相似文献   
7.
The aim of this work was to quantify the ability to predict intrafraction diaphragm motion from an external respiration signal during a course of radiotherapy. The data obtained included diaphragm motion traces from 63 fluoroscopic lung procedures for 5 patients, acquired simultaneously with respiratory motion signals (an infrared camera-based system was used to track abdominal wall motion). During these sessions, the patients were asked to breathe either (i) without instruction, (ii) with audio prompting, or (iii) using visual feedback. A statistical general linear model was formulated to describe the relationship between the respiration signal and diaphragm motion over all sessions and for all breathing training types. The model parameters derived from the first session for each patient were then used to predict the diaphragm motion for subsequent sessions based on the respiration signal. Quantification of the difference between the predicted and actual motion during each session determined our ability to predict diaphragm motion during a course of radiotherapy. This measure of diaphragm motion was also used to estimate clinical target volume (CTV) to planning target volume (PTV) margins for conventional, gated, and proposed four-dimensional (4D) radiotherapy. Results from statistical analysis indicated a strong linear relationship between the respiration signal and diaphragm motion (p<0.001) over all sessions, irrespective of session number (p=0.98) and breathing training type (p=0.19). Using model parameters obtained from the first session, diaphragm motion was predicted in subsequent sessions to within 0.1 cm (1 sigma) for gated and 4D radiotherapy. Assuming a 0.4 cm setup error, superior-inferior CTV-PTV margins of 1.1 cm for conventional radiotherapy could be reduced to 0.8 cm for gated and 4D radiotherapy. The diaphragm motion is strongly correlated with the respiration signal obtained from the abdominal wall. This correlation can be used to predict diaphragm motion, based on the respiration signal, to within 0.1 cm (1 sigma) over a course of radiotherapy.  相似文献   
8.
Maternal and Child Health Journal - National studies report that birth center care is associated with reduced racial and ethnic disparities and reduced experiences of mistreatment. In the US, there...  相似文献   
9.

Aim:

To compare the efficacy and safety of oral transmucosal fentanyl citrate (OTFC) and oral morphine in Indian patients with breakthrough episodes of cancer pain.

Materials and Methods:

In this randomized, open label, active controlled, clinical study, total 186 patients who regularly experienced 1-4 episodes of breakthrough cancer pain (BTCP) daily, over the persistent pain controlled by taking oral morphine 60 mg/day or its equivalent were randomized to receive either OTFC 200 mcg or oral morphine 10 mg for the treatment of BTCP for 3 days. Improvement in pain as determined by numerical rating scale (NRS) at 5, 15, 30, and 60 minutes of drug administration and percentage of BTCP episodes showing reduction in pain intensity by >33% at 15 minutes were primary efficacy endpoints. Secondary efficacy endpoints were requirement for rescue analgesia and global assessment by physician and patient. Data of both treatment groups were analysed by appropriate statistical test using software, STATISTICA, version 11.

Results:

Patients treated with OTFC experienced significantly greater improvement in pain intensity of breakthrough episodes compared to those treated with oral morphine at all assessment time points (P < 0.0001). 56% of breakthrough pain episodes treated with OTFC showed a greater than 33% reduction in pain intensity from baseline at 15 minutes compared to 39% episodes treated with oral morphine (P < 0.0001). Patient''s and physician''s global assessment favoured OTFC than oral morphine (P < 0.0001). Requirement of rescue analgesia in both the study groups was similar (P > 0.05). Both study drugs were well tolerated.

Conclusions:

OTFC was found to provide faster onset of analgesic effect than immediate release oral morphine in management of breakthrough cancer pain.  相似文献   
10.
Multiple idiopathic cervical resorption is an uncommon condition, the etiology of which remains unknown. The case of a 36-year-old woman with idiopathic resorption in the cervical areas of multiple teeth is presented. Her medical history was noncontributory, but her dental history was valuable in reaching a diagnosis. Hematologic and endocrinal investigations were unremarkable, but a computed tomography scan revealed relevant information. The progression of the lesion and involvement of multiple teeth without any pattern or chronology are challenges faced when diagnosing and treating this condition.  相似文献   
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