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991.
Perception of complex sound is a process carried out in everyday life situations and contributes in the way one perceives reality. Attempting to explain sound perception and how it affects human beings is complicated. Physics of simple sound can be described as a function of frequency, amplitude and phase. Psychology of sound, also termed psychoacoustics, has its own distinct elements of pitch, intensity and tibre. An interconnection exists between physics and psychology of hearing.  相似文献   
992.
Prevalence of GJB2 mutations in prelingual deafness in the Greek population   总被引:6,自引:0,他引:6  
OBJECTIVE: Mutations in the gene encoding the gap junction protein connexin 26 (GJB2) have been shown as a major contributor to prelingual, sensorineural, nonsyndromic, recessive deafness. One specific mutation, 35delG, has accounted for the majority of the mutations detected in the GJB2 gene in Caucasian populations. The aim of our study was to determine the prevalence and spectrum of GJB2 mutations in prelingual deafness in the Greek population. METHODS: In a collaboration with the major referral centers for childhood deafness in Greece, patients were examined by an extensive questionnaire to exclude syndromic forms and environmental causes of deafness and by allele-specific polymerase chain reaction (PCR) for the detection of the 35delG mutation. Patients heterozygous for the 35delG mutation were further analyzed by direct genomic sequencing of the coding region of the GJB2 gene. RESULTS: The 35delG mutation was found in 42.2% of the chromosomes in 45 familial cases of prelingual, nonsyndromic deafness (18 homozygotes and 2 heterozygotes) and in 30.6% of the chromosomes in 165 sporadic cases (45 homozygotes and 11 heterozygotes). Direct genomic sequencing in heterozygous patients revealed the L90P (2 alleles), W24X (2 alleles), R184P (2 alleles), and 291insA (1 allele) mutations. CONCLUSION: Mutations in the GJB2 gene are responsible for about one third of prelingual, sensorineural, nonsyndromic deafness in the Greek population, and allele-specific PCR is an easy screening method for the common 35delG mutation.  相似文献   
993.
Osteopenia and osteoporosis are currently receiving particular attention as late effects of therapy in survivors of childhood acute lymphoblastic leukemia (ALL). The aim of this study was to evaluate abnormalities in bone mass and mineral homeostasis in children with ALL after induction therapy (during consolidation treatment). Lumbar spine (L2-L4) bone mineral density (BMD, g/cm(2)) was measured by dual energy X-ray absorptiometry in 20 children with ALL, a median of 25.9 months postdiagnosis and results were expressed as z-scores relative to healthy Caucasian children (controls). Serum levels of intact parathyroid hormone (iPTH), alkaline phosphatase (ALP), calcium, phosphate, and magnesium were also analyzed. In addition, the body mass indexes (kg/cm(2)) of patients and controls were calculated. Results were compared with those of 40 healthy controls. Among the 20 children with ALL (12 boys and 8 girls), 12 presented z-scores < 1 SD (normal) and 8 were osteopenic (z-score between 1 and 2.5 SD). In addition, children with ALL had reduced lumbar BMDs (z-score -0.817) in comparison to healthy controls (z-score -0.353) (p = .04). Moreover, alkaline phosphatase and intact parathyroid hormone values were significantly increased compared to controls values. The data demonstrate that bone metabolism in children with ALL during consolidation therapy is disturbed, resulting in a reduced BMD and z-score with respect to healthy controls. Since a reduced BMD predisposes to osteopenia and osteoporosis, specific attention and therapeutic interventions should be considered.  相似文献   
994.
PROBLEM: The aim of this study was to investigate the effect of valacyclovir treatment on natural killer (NK) cell concentration in the peripheral blood of infertile women. METHOD OF STUDY: Peripheral blood NK cell concentration of 104 non-pregnant women with a history of infertility was determined by flow cytometry. The controls were 14 fertile non-pregnant women. A cohort of 42 out of 104 women--whose NK cell levels were 175/microL or higher--was prospectively studied for the presence of HSV-1, 2, VZV, cytomegalovirus, HHV-6, HHV-7 and HHV-8 DNA in the peripheral blood and was orally administered valacyclovir (open label study). RESULTS: Herpes virus DNA was detected in 64.3% of the 42 women examined. Prior to valacyclovir treatment mean NK cell concentration in herpes-negative group was statistically higher from control group but lower from herpes positive group (P = 0.0007, ANOVA). Following valacyclovir treatment the mean NK cell concentration was statistically decreased in all studied women (P = 0.000453), in herpes-negative (P = 0.01622) and in herpes positive group (P = 0.0056). Sufficient decrease was observed in 31 (73.8%) of 42 women who received the drug. CONCLUSIONS: Valacyclovir treatment is associated with a decrease of NK cell levels in most of the women with a history of infertility.  相似文献   
995.
We report a case of a 55-yr-old man with malignant melanoma of scrotum. He was referred to our Hospital with a complaint of gradual focal enlargement of the scrotum in a period of 3 yr. On physical examination, a pigmented, poorly marginated mass, with central necrosis was observed. A fine-needle aspiration (FNA) of the lesion was performed. Cytological examination revealed highly cellular smears, containing malignant cells, dispersed or arranged in loose aggregates. Cellular morphology and characteristics were identical to those of malignant melanoma arising elsewhere in the skin. The immunocytochemical study revealed positivity of neoplastic cells for anti-melanoma monoclonal antibody (HMB-45) antigen. Histological confirmation finally was provided after wide excision of the lesion. We emphasize the difficulties in differential diagnosis considerations and diagnostic pitfalls of scrotal lesions.  相似文献   
996.
997.
Selective clinical management of anterior abdominal stab wounds   总被引:3,自引:0,他引:3  
BACKGROUND: The optimal management of clinically stable patients with anterior abdominal stab wounds (AASWs) is debated. We implemented a protocol of serial clinical assessments to determine the need for laparotomy. The purpose of this study was to determine whether the approach is safe and effective. METHODS: Records of patients sustaining AASWs from 1999 to 2003 were reviewed. RESULTS: Seventy-seven patients sustained AASWs. Twenty-five were taken directly to the operating room because of hypotension (5), evisceration (7), or peritonitis (15). Seventeen patients had diagnostic peritoneal lavage (DPL) for associated thoracoabdominal wounds and 5 had local wound exploration (LWE) off protocol. The remaining 30 patients were managed with serial clinical assessments and were discharged uneventfully. CONCLUSION: Patients sustaining AASWs who present without hypotension, evisceration, or peritonitis may be managed safely under a protocol of serial clinical evaluations. This approach should be compared with LWE/DPL in a prospective, randomized multicenter trial.  相似文献   
998.
999.
OBJECTIVE: Postoperative neurologic deficits after thoracic aortic reconstruction vary widely. Our previous study showed that delayed ischemic preconditioning could prevent spinal cord injury caused by occlusion of the descending thoracic aorta in pigs. We investigated early ischemic preconditioning in the same model. METHODS: Twenty-eight pigs were divided into 4 groups: group 1 (n = 6) underwent a sham operation, group 2 (n = 6) underwent aortic occlusion for 20 minutes, group 3 (n = 8) underwent aortic occlusion for 35 minutes, and group 4 (n = 8) underwent aortic occlusion for 20 minutes and underwent aortic occlusion 80 minutes later without hypotension for 35 minutes. Aortic occlusion was accomplished by using 2 balloon occlusion catheters placed fluoroscopically at T6 to T8 above the diaphragm and at the aortic bifurcation. Neurologic evaluation was performed by an independent observer according to the Tarlov scale (0-4). The lower thoracic and lumbar spinal cords were harvested at 120 hours and examined histologically with hematoxylin-and-eosin stain. Histologic results (number of neurons and grade of inflammation) were scored (0-4) and were similarly analyzed. Statistical analysis was by means of the Kruskal-Wallis test. RESULTS: Group 4 had a better neurologic outcome at 24, 48, and 120 hours in comparison with group 3 (P <.001). The histologic changes were proportional to the neurologic test scores, with the more severe and extensive gray matter damage in animals of group 3 (number of neurons, P <.001; grade of inflammation, P <.001). CONCLUSION: Early ischemic preconditioning without hypotension protects against spinal cord injury after aortic occlusion, as confirmed by using the Tarlov score and histopathology.  相似文献   
1000.
The standard CHOP regimen may cure 30-40% of patients with advanced aggressive non-Hodgkin's lymphoma (ANHL). Mitoxantrone is an anthracenedione, which is active in NHL and its toxicity profile may be more favorable than doxorubicin with respect to alopecia, mucositis and cardiotoxicity. This study was designed to compare the effectiveness of an escalated dose of mitoxantrone with that of standard doxorubicin, used in the CHOP regimen in patients with ANHL. One hundred and forty three eligible patients with ANHL were randomized to receive 6 cycles of either CHOP (n = 71) or intensified CNOP (iCNOP) (n = 72), with mitoxantrone 20 mg/m2, i.v., d.1 instead of doxorubicin. Complete responders (CR) were again randomized either to receive interferon-alpha (IFN-alpha) maintenance (3 MU t.i.w., s.c.) or not. The CR rate was 70 vs. 76% for iCNOP and CHOP (p = 0.45), and the overall response rate was 81 vs. 83%, respectively (p = 0.71). The 5-year failure free survival (FFS) was 48 and 50% in the iCNOP and CHOP arm, respectively (p = 0.45), and the 5-year overall survival (OS) was 61 vs. 64% (p = 0.56). IFN-alpha did not prolong relapse free survival (p = 0.91). iCNOP produced less alopecia (p = 0.001) but more febrile episodes (p = 0.04) than CHOP, while requiring more frequent G-CSF support (p = 0.01). Two cases of acute myelogenous leukemia (AML) were recorded, both in the iCNOP arm (p = 0.14). In conclusion, iCNOP was equally effective to CHOP in patients with ANHL, producing more leukopenia and febrile episodes, but less alopecia. The development of two cases of secondary AML in th e iCNOP arm is of concern.  相似文献   
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