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71.
Removal of extensive central skull base and paranasal sinus tumors is a significant challenge that is often hampered by limited access and exposure. The safety and efficacy of the Le Fort I osteotomy approach to the skull base have been well established. The purpose of this article is to describe the use of Le fort-1I osteotomy as an access procedure to reach tumors in the nasopharyngeal region in a young patient. The large mass which he presented within the nasopharyngeal region, later diagnosed to be juvenile nasopharyngeal angiofibroma, posed a challenge for surgical access.  相似文献   
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Background and objective: Recently, there has been interest in the sensation of irritation that precedes the motor act of coughing, which has been termed the urge‐to‐cough (UTC). The aim of this study was to perform the largest evaluation to date of the UTC threshold (Cu) in a healthy population. The specific aims were to investigate the relationship between Cu and cough reflex sensitivity, to evaluate gender differences in the UTC and to assess the reproducibility of measurements of Cu. Methods: Standard capsaicin cough challenge methodology was employed to measure cough reflex sensitivity in 100 healthy adult non‐smokers (50 females) with the additional measurement of Cu. A subgroup of 40 subjects (20 males) underwent repeat cough challenges after 1 week to examine the reproducibility of the measurements. Results: All 100 subjects demonstrated motor cough in response to capsaicin. Twenty‐one subjects (10 females) did not show a discernible Cu, as the motor cough event preceded a UTC sensation unaccompanied by cough. Although cough reflex sensitivity, as measured by the concentration of capsaicin inducing five or more coughs (C5), was enhanced in women, there was no gender difference in Cu. Similar to standard cough reflex sensitivity measurements, the measurement of Cu was highly reproducible. Conclusions: These results demonstrate that the UTC threshold can be effectively and reproducibly measured using a modification of standard cough challenge methodology. Given its clinical significance as a prevalent symptom, UTC, as measured by Cu, represents an additional relevant end point for studies investigating the effects of pharmacological and other interventions in cough and cough reflex sensitivity.  相似文献   
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Laboratory diagnostics are a core component of any pneumonia etiology study. Recent advances in diagnostic technology have introduced newer methods that have greatly improved the ability to identify respiratory pathogens. However, determining the microbial etiology of pneumonia remains a challenge, especially in children. This is largely because of the inconsistent use of assays between studies, difficulties in specimen collection, and problems in interpreting the presence of pathogens as being causally related to the pneumonia event. The laboratory testing strategy for the Pneumonia Etiology Research for Child Health (PERCH) study aims to incorporate a broad range of diagnostic testing that will be standardized across the 7 participating sites. We describe the current status of laboratory diagnostics for pneumonia and the PERCH approach for specimen testing. Pneumonia diagnostics are evolving, and it is also a priority of PERCH to collect and archive specimens for future testing by promising diagnostic methods that are currently under development.  相似文献   
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A heterostructure of WS2/WO3·H2O has been prepared by partial oxidation of WS2 nanosheets by exposing bulk WS2 micron powder to ultrasonic waves in a bath sonicator. The as-prepared nanomaterial was used as a sensing film in an interdigitated electrode-based gas detecting device. The device was found to be specific towards ammonia gas among a group oxidizing and reducing gases. In particular, a response of as high as 11.36–254.66% was recorded for ammonia concentrations of 50 ppb to 2 ppm with excellent repeatability and reproducibility at room temperature. The response time and recovery time of the device was found to be a few tens of seconds suggesting its practicability. A plausible mechanism based on different active sites present in the receptor film is proposed and a logical reason behind its specificity towards ammonia gas is also inferred based on the Lewis acidic centers on the nano-surfaces. Overall, this proposed nanomaterial has very high potential for practical use as a room temperature ammonia sensor.

A tungsten sulfide/tungstite heterostructure is prepared via a modified liquid exfoliation technique. A chemiresistive sensor based on this nanomaterial demonstrates excellent sensitivity and selectivity towards ammonia gas even at room temperature.  相似文献   
78.
The anesthetic implications of Joubert syndrome in an infant who required cardiac surgery using cardiopulmonary bypass (CPB) is presented. Children with Joubert syndrome present with central apnea due to malformations in the midbrain and cerebellum. These patients have a marked sensitivity to opioids. The use of dexmedetomidine along with remifentanil was effective in this case.  相似文献   
79.

Background

Infection with Plasmodium vivax, a common human parasite, is occasionally recognized to cause severe organ dysfunction similar to P. falciparum infection. Acute kidney injury (AKI) in malaria is attributed to acute tubular necrosis; thrombotic microangiopathy is not described.

Methods

This observational study includes patients referred to a tertiary care center in North India during June to September 2011 with severe AKI, anemia, and thrombocytopenia following vivax malaria. Renal biopsies were processed by light, immunofluorescence, and electron microscopy.

Results

Nine patients (including 5 children) had persistent AKI with thrombocytopenia and variable anemia following the diagnosis of malaria. Based on peripheral smear, eight patients were diagnosed with vivax malaria and had received antimalarial therapy prior to referral; a laboratory diagnosis of P. vivax infection was made for one patient at this center. Renal histology in all cases showed features of thrombotic microangiopathy, including fibrin thrombi, subendothelial widening, and mesangiolysis, along with variable tubulointerstitial nephritis and acute tubular or cortical necrosis. Ultrastructural examination confirmed endothelial injury and subendothelial widening. All patients required hemodialysis, and six were dialysis dependent at four weeks. Delayed presentation to the hospital (P = 0.019), hemolysis on peripheral smear (P = 0.083), and prolonged oligoanuria (P = 0.036) were associated with dialysis dependence.

Conclusion

The association of anemia, thrombocytopenia, and renal histological evidence of thrombotic microangiopathy with vivax malaria is novel, and suggests the presence of severe endothelial injury. Further studies are necessary to confirm the association and examine the factors associated with its occurrence.  相似文献   
80.
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