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21.
Listeners with sensorineural hearing loss (SNHL) struggle to understand speech, especially in noise, despite audibility compensation. These real-world suprathreshold deficits are hypothesized to arise from degraded frequency tuning and reduced temporal-coding precision; however, peripheral neurophysiological studies testing these hypotheses have been largely limited to in-quiet artificial vowels. Here, we measured single auditory-nerve-fiber responses to a connected speech sentence in noise from anesthetized male chinchillas with normal hearing (NH) or noise-induced hearing loss (NIHL). Our results demonstrated that temporal precision was not degraded following acoustic trauma, and furthermore that sharpness of cochlear frequency tuning was not the major factor affecting impaired peripheral coding of connected speech in noise. Rather, the loss of cochlear tonotopy, a hallmark of NH, contributed the most to both consonant-coding and vowel-coding degradations. Because distorted tonotopy varies in degree across etiologies (e.g., noise exposure, age), these results have important implications for understanding and treating individual differences in speech perception for people suffering from SNHL.SIGNIFICANCE STATEMENT Difficulty understanding speech in noise is the primary complaint in audiology clinics and can leave people with sensorineural hearing loss (SNHL) suffering from communication difficulties that affect their professional, social, and family lives, as well as their mental health. We measured single-neuron responses from a preclinical SNHL animal model to characterize salient neural-coding deficits for naturally spoken speech in noise. We found the major mechanism affecting neural coding was not a commonly assumed factor, but rather a disruption of tonotopicity, the systematic mapping of acoustic frequency to cochlear place that is a hallmark of normal hearing. Because the degree of distorted tonotopy varies across hearing-loss etiologies, these results have important implications for precision audiology approaches to diagnosis and treatment of SNHL.  相似文献   
22.
Introduction Coronary artery bypass grafting (CABG) associated with Endarterectomy is a high risk procedure. After the first report of coronary endarterectomy by Bailey et al in 1951, the preference for this surgical procedure was decreased due to increased morbidity and mortality In patients with total or subtotal large coronary artery obstructions in which there is no possibility to receive a conduit as graft for myocardial revascularisation, endarterectomy remains the procedure of choice. This study was designed to study early and midterm results of off pump coronary artery endarterectomy. Methods Of 172 Consecutive Off Pump CABG done at our institution from Jan 2003 to July 2005, 22 patients underwent supplementary coronary endarterectomy. 16 patients had chronic stable angina 4 had unstable angina two required emergency CABG with endarterectomy following perioperative infarction. The mean ejection fraction was 29.2±4.3 and all of the patients were in New York Heart Association (NYHA) III or IV. All patients were planned for complete total arterial revascularisation using Left Internal Mammary Artery (LIMA). Right Internal Mammary Artery (RIMA), Radial composite “Y” graft, Two patients operated for periop infarct received vein graft. In 16 patients closed endarterectomy was done in five patients double endarterectomy in single vessel was done to chase the plaque distally, in one patient open left anterior descending (LAD) endarterectomy with vein patch reconstruction was performed. Results There were no deaths. None of the procedures were converted to on pump operation. All endarterectomies and bypasses were performed on Beating Heart, all patients were completely revascularised. Peri operative cardiac enzymes studied showed no significant rise in the Creatinine Phoshpokinase (CPK)-Creatinine Phosphokinase myocardial Band (CPK-MB). The mean postoperative Ejection Fraction (EF) was 36.7%±7.2% which was significantly higher than the Preoperative one (p<.05). At the end of four months to one and half year 22 patients were in NYHA class I to II and all were angina free in canadian cardiovascular society class.f Conclusions Coronary End Arterectomy without cardiopulmonary bypass can be performed in patients who are expected to benefit from complete revascularisation. It can be performed with closed as well as open method. However to achieve complete endarterectomy by closed technique in some patients it is essential to chase the plaque. Early and mid term results are encouraging.  相似文献   
23.
Background  In 1991, Delaitre reported the first laparoscopic splenectomy (LS). Since then LS has become the procedure of choice to treat hematological diseases requiring splenectomy. The Eastern province of Saudi Arabia is known to have a high incidence of hemoglobinopathies including sickle cell disease (SCD), which is known to be associated with complications necessitating splenectomy and/or cholecystectomy. This report describes our experience with LS and/or laparoscopic cholecystectomy (LC) for children with SCD. Patients and methods  The medical records of all children with SCD who had LS and/or LC were retrospectively reviewed for age, sex, indication for splenectomy, operative time, hospital stay, and post-operative complications. The results were compared to a similar group of children with SCD who had open splenectomy (OS) and/or open cholecystectomy (OC). Results  Over a period of 3.5 years (January 2005 and June 2008), a total of 45 children had LS with or without LC, 30 (66.7%) of them had SCD. Their age ranged from 2 to 12 years (mean 7 years). There were 16 males and 14 females. In all, LS was done because of recurrent splenic sequestration crisis except one who had a large spleen with multiple infarcts that was causing abdominal pain. The operative time ranged from 1.5 to 9 h (mean 2.75 h). Their hospital stay ranged from 3 to 9 days (mean 4.5 days). There was no mortality. Two patients (6.7%) required conversion to OS due to a large-sized spleen and severe adhesions in one and uncontrolled intra-operative bleeding in the other. The results were compared to a group of 120 children with SCD who had OS only (88) and OS with OC (32). From 1994 to 2006, a total of 55 children had LC only, 47 (26 M:21 F) of them (85.5%) had SCD. Their age ranged from 4 to 15 years (mean 11.4 years). The indications for cholecystectomy were: biliary dyspepsia (20), biliary colic (35), acute cholecystitis (5), obstructive jaundice (5), asymptomatic (6), and biliary pancreatitis (1). There was no mortality, but one (2.1%) required conversion to OC because of severe adhesions and another underwent postoperative exploration because of bleeding from an accessory cystic artery. The results were compared to a similar group of 27 children with SCD who underwent OC. Conclusions  With good peri-operative management, LS is feasible and safe in children with SCD and can be done concomitantly with cholecystectomy. Currently, it requires more operative time than the open approach. This is specially so for children with SCD who are known to have a large spleen with severe adhesions. It is, however, superior to OS with regard to duration of hospital stay, cosmetic appearance, post-operative complications, and post-operative recovery. LC is also safe in children with SCD. When compared with OC, it is associated with less post-operative complications, a shorter hospital stay, better cosmetic appearance and a faster recovery.  相似文献   
24.
Peste des petits ruminants (PPR) is an economically important disease of small ruminants with a rapidly expanding geographical distribution. Peste des petits ruminants virus may manifest in a variety of ways with disease ranging from acute to subclinical. We investigated the exposure of large ruminants to PPRV in areas where the virus is endemic in the small ruminant population by assessing the serological status of groups of animals. This study focused on the Punjab province of Pakistan as an area where the virus is endemic and where mixed farming practices occur enabling close interactions between small and large ruminant populations. An overall PPR seropositivity was detected in 10.0% of cattle and 14.16% of buffaloes. Following an assessment of serological profiles in large ruminants within different age groups, a maximum seroprevalence was observed in cattle (17.5%) and buffaloes (22.5%) over 2 years of age indicating the potential utility of sampling large ruminant populations for PPR serosurveillance. The large ruminants sampled between one and two years of age had similar levels of seropositivity within populations with 11.2% and 16.2% of animals being seropositive, respectively. Current PPR vaccination strategies do not enable the differentiation between infected and vaccinated small ruminants, and as such, the serological surveillance of sheep and goats is of little value. When considering eradication programmes for PPRV, this factor is of great significance. However, where large and small ruminants are farmed together, serological surveillance of large ruminants may provide a snapshot of virus infection within populations where mild disease is present or where small ruminants are regularly vaccinated.  相似文献   
25.
Rosai Dorfman disease or sinus histiocytosis is a rare, idiopathic, benign and self-limiting histiocytic proliferative disorder, usually seen in younger patients. It most commonly involves the cervical lymph nodes, with a predominant infiltration of sinusoidal histiocytes and classically presents with massive cervical lymhadenopathy. Extranodal disease occurs in about 43% of cases and produces different signs and symptoms depending upon its location. We report a case of this disorder in 22-year-old male with initial isolated involvement of bilateral nasal cavity and paranasal sinuses with subsequent involvement of cervical lymph nodes and skin. The clinical presentation, histologic characterstics, radiographic findings and treatment of the disease are discussed.  相似文献   
26.
Three cases of thanatophoric dwarfism are reported from Libya during a period of 16 months showing an incidence of 1:5600 total births. Polyhydramnios was associated with all the three cases and maternal diabetes in one. No known pattern of inheritance was found. One was stillborn and other two died within 30 minutes of birth. The detailed diagnostic features and differential diagnosis is described along with a brief review of literature.  相似文献   
27.
A strain of Clostridium botulinum type E has been isolated from soil samples of Gwalior, India. The isolated strain shows curved vegetative cells with oval, bulging, and terminal spores. The production of toxin was detected by immunodiffusion test, symptomatic death of mice and mouse protection assay with trivalent antitoxin (A+B+E). The culture supernatant gave 10(3) MLD (minimum lethal dose) per ml without any protease treatment. Group specific and serotype specific primers amplified the DNA fragments of 260 bp and 445 bp, respectively, indicating Clostridium botulinum type 'E.'  相似文献   
28.
29.
OBJECTIVE: To determine the extent to which physical status at birth is associated with neonatal mortality and the causes of mortality vis-a-vis size at birth and gestational age. METHOD: 11,223 consecutive live births completing 26 weeks of gestation and weighing > or = 500 gm were included in the study. Birth weight and chest circumference were recorded as per WHO guidelines. Gestational age was calculated on the basis of L.M.P. and the new Ballard's score. Deaths occurring in the hospital within 28 days were recorded. Percentile values of gestational age specific birth weights were calculated separately for singletons and multiple births. Percentage of SGA was calculated with reference to WHO recommended values. Birth weight-gestational age-specific mortality rates were calculated at 2 wk and 500 gm intervals. RESULT: Low-birth-weight babies constituted 39.8% of the total, much in excess of WHO recommended figure of 15%. 76% deaths occurred among LBW babies and 56.2% among preterms. Mortality showed remarkable decline as the birth weight increased to 2,000 gm. The lowest mortality was among singletons weighing 2,500-3,000 gm and of 38-40 weeks gestation. Prevalence of SGA at 40 and 42 weeks were 73.7% and 83.6% respectively. But, if SGA babies not categorised as LBW were excluded, the values came down to 32% and 36% respectively. 36% of all deaths occurred during the first 24 hrs of birth; asphyxia and related causes contributing to 50% of it. CONCLUSION: Cut-off value of 2,000 gm instead of 2,500 gm for birth weight may be preferable in countries where most LBW babies are SGAs. Simultaneously, deaths in non-LBW babies due to perinatal causes contribute sgnificantly to total neonatal mortality and need due attention through sensitising obstetricians in essential newbom care and timely Intervention.  相似文献   
30.
First described as a pleural neoplasm, the solitary fibrous tumor (fibrous mesothelioma) has been reported in a number of extrapulmonary sites, including the Head-Neck region. In the Head-Neck region, it has been described in the sinonasal tract, epiglottis, parapharyngeal, retropharyngeal spaces, parotid and infratemporal fossa. We present the second case of solitary fibrous tumor of infratemporal fossa described in world literature. A complete excision was achieved by transmaxillary approach.  相似文献   
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