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991.
The primary advances in speech and audio signal processing that contributed to the maturing of multimedia applications are discussed in the areas of speech and audio signal compression, speech synthesis, acoustic processing and echo control, and network echo cancellation 相似文献
992.
OBJECTIVE: To identify the influence of the increased level of serum cholyglycine (CG) on lipid metabolism and hemorrheology in patients with intrahepatic cholestasis during pregnancy (ICP). METHODS: The concentrations of serum CG, total cholesterol (CH), triglycerides (TG), high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C), high shear and low shear of blood specific viscosity (HS and LS), plasma specific viscosity (PV) and hematocrit (HCT) were measured in 68 cases of primiparas with single pregnancy and 30 healthy nonpregnant women respectively. The group of ICP was composed of 35 cases with CG > 6 mumol/L, the group of normal pregnancy, 33 cases with CG < 6 mumol/L. RESULTS: The means of CG and the lipidic parameters in the two pregnant groups were significantly higher than those in the non-pregnancy group (P < 0.02-0.001) except the means of HDL-C between the groups of ICP and non-pregnancy. The levels of LDL-C, LDL-C/HDL-C, LS, PV and HCT in the ICP were significantly higher than those in the normal pregnancy group (P < 0.02-0.001). CONCLUSIONS: There are significant changes of lipid metabolism and hemorrheology in patients with ICP. However, these changes could be corrected after pregnancy termination, when the level of serum CG returned to normal. The results suggest that the pathophysiologic changes of ICP are associated with increased level of serum CG. 相似文献
993.
994.
PURPOSE: To report a patient with acute retinal pigment epitheliitis examined less than 24 hours after onset of symptoms. METHOD: One day after the onset of blurred vision in her left eye, a 33-year-old woman had a best-corrected visual acuity of LE, 20/60 -2. The left eye had classic uniform golden-colored nodules in a honeycomb pattern in the foveal retinal pigment epithelium. Intravenous fundus fluorescein angiography disclosed staining of the foveal pigment epithelium. RESULTS: One month after initial examination, visual acuity was LE, 20/20, and fine subfoveal pigmentary clumping was present. CONCLUSION: The pigmentary maculopathy of acute retinal pigment epitheliitis may be nonspecific, resulting from more than one type of primary foveal inflammation. 相似文献
995.
Children with autism and children with Down's syndrome watched the following enactment. A protagonist put one item in location A and another in location B and then left the scene. Subsequently, the items were swapped the other way round. Finally, the protagonist (who remained ignorant of the swap) requested the item in A. The observing child participant was asked to judge (1) which item the protagonist wanted and (2) which item the protagonist put in A. Unlike children with Down's syndrome, those with autism made more errors in judging that the speaker wanted the item in B than in judging that the item the speaker put in A is now in B; children with autism wrongly tended to interpret utterances literally, and they did this significantly more frequently than children with Down's syndrome. We conclude that children with autism have a difficulty making nonliteral interpretations that cannot be explained as (1) a realist bias, (2) an inability to inhibit a prepotent response, and (3) a failure to keep track of the exchange of items. 相似文献
996.
JM Bach H Otto GT Nepom G Jung H Cohen J Timsit C Boitard PM van Endert 《Canadian Metallurgical Quarterly》1997,10(4):375-386
Tissue composition and the distribution of body mass are described for four genera of East African Bovidae (Madoqua, Gazella, Damaliscus, Hippotragus) with supporting data from four others (Neotragus, Oryx, Tragelaphus, Connochaetes). These species are high in muscle mass, an adaptation convergent with other high-speed terrestrial cursors, bounders, and saltators. The segments below the elbow/cubitus and knee/stifle/genu joints in small bovids are both lighter in percent of total body mass (8.6% TBM) and less heavily muscled (10-15% of total limb musculature) than those segments in macaques (13.6% TBM, 20-25% of the limb musculature). Bovid species differ from one another in the regional distribution of muscle mass. Madoqua kirkii (4-5 kg) concentrates muscle in the lumbar extensors and hindlimbs; large species such as Damaliscus doreas (50-60 kg) and Hippotragus niger (160-220 kg) distribute it more evenly between the lumbar and cervical regions and between the hindlimbs and forelimbs. Gazella dorcas (10-20 kg) is quantitatively intermediate in those characteristics. The redistribution of muscle mass with increasing size correlates with the loss of axial bending of the vertebral column: in small, hindlimb dominant, 'dorsomobile' species such as Madoqua sagittal mobility increases stride length through 'extended' suspension; in large 'dorsostable' species such as Damaliscus and Hippotragus the vertebral column resists bending, consequently abbreviating or omitting this non-contact phase of the gait cycle. Locomotor adaptation as it is reflected in size, shape, and musculoskeletal structure is the key to habitat choice, dietary specialization, social structure, and male agonistic behavior and, therefore, central to the fabric of behavioral ecology. 相似文献
997.
K Peris MT Onorati G Keller F Magrini P Donati L Muscardin H H?fler S Chimenti 《Canadian Metallurgical Quarterly》1997,137(3):356-360
OBJECTIVE: Thoracic injury remains a major source of morbidity and mortality in urban trauma centers. With the advent and increasing expertise in video assisted thoracic surgery, this modality has become an attractive alternative in the management of patients with thoracic injury. This report will review our experience with video assisted thoracic surgery at a level I trauma center and attempt to further delineate the indications for and timing of thoracoscopy in thoracic trauma. METHODS: We identified 16 patients who had undergone video assisted thoracic surgery following chest trauma between July 1991 and June 1994. There were 15 penetrating and one blunt trauma. All 16 patients were initially treated with tube thoracostomy. From 0-20 days post-injury, video assisted thoracic surgery was attempted with either diagnostic or therapeutic intentions. RESULTS: Twelve of the 16 patients (75%) had successful thoracoscopy. Three patients had diaphragmatic injury excluded and nine patients had successful evacuation of clotted hemothoraces. Evacuation of clotted hemothorax up to 7 days post-injury was safe and easily accomplished. Four patients (25%) had unsuccessful thoracoscopy and were converted to standard thoracotomy; failure was attributed to either suboptimal single lung ventilation or severe pleural inflammatory reaction. The only death in the entire group occurred 10 days after a thoracotomy for retained hemothorax. The median post-operative hospital stay following successful video assisted thoracic surgery was 3.5 days. CONCLUSIONS: Video assisted thoracic surgery can be utilized as an effective and safe method for the initial diagnostic evaluation and surgical management of stable patients with penetrating thoracic trauma. 相似文献
998.
Paraquat (1,1'-dimethyl-4,4'-dipyridylium) is an herbicide associated with both accidental and intentional ingestion, leading to severe and often fatal toxicity. Prognosis is largely dependent on the amount of paraquat absorbed. Rapid identification of the symptoms of paraquat toxicity (burns or ulceration at the site of ingestion or injection, acute respiratory distress, and renal failure) can facilitate early treatment intervention to limit absorption. We report a case of a 71-year-old man with a suicidal ingestion of paraquat 2 days prior to presentation. Serum paraquat levels, time elapsed since ingestion, and clinical symptoms all indicated poor prognosis. The patient developed severe respiratory distress and progressive renal failure, and died 6 days after admission to the hospital. 相似文献
999.
The chronic Pseudomonas aeruginosa lung infection in cystic fibrosis (CF) is characterized by a pronounced antibody response and microcolonies surrounded by numerous polymorphonuclear neutrophils (PMN). Poor prognosis is correlated with a high antibody response to P. aeruginosa antigens. An animal model of this infection was established in two strains of mice: C3H/HeN and BALB/c, generally known as Th1 and Th2 responders, respectively, which were challenged with alginate-embedded P. aeruginosa. Mortality was significantly lower in C3H/HeN compared to BALB/c mice (p < 0.025). P. aeruginosa was cleared more efficiently in C3H/HeN mice and significantly more C3H/HeN mice showed normal lung histopathology (p < 0.02), and we found significantly fewer microabscesses in C3H/HeN mice than in BALB/c mice (p < 0.005). In supernatants from P. aeruginosa antigen and concanavalin A-stimulated spleen cells from the two strains of mice, the interferon-(IFN-) gamma levels were higher, whereas IL-4 levels were lower in C3H/HeN mice than in BALB/c mice. The implications of these findings for CF patients with chronic P. aeruginosa lung infection are discussed. 相似文献
1000.
A new technique is introduced to construct generic morphological operators quickly and automatically using input-output pairs of images as training samples. This process can be modelled as generalised PAC (probably approximately correct) learning. A new representation for morphological operators, much more efficient than the traditional one, is also proposed 相似文献