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991.
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   
992.
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   
993.
A clinical study was conducted to compare the analgesic effect of clonidine with those of sumatriptan and their mixture and their effects on hemodynamics. 40 patients undergoing elective total hysterectomy were randomly divided into 4 groups in terms of the epidurally administered drugs with 10 patients in each group (group C1: clonidine 150 micrograms, group C2: clonidine 75 micrograms, group S: sumatriptan 6 mg and group S + C: clonidine 75 micrograms + sumatriptan 3 mg). MAP, HR, SpO2, VT VAS, VRS and ePDT were measured in the initial 4 h. The demographic data and the doses of intraoperative local anesthetics among the 4 groups were not statistically different. It was found that no significant difference in the pre- and postadministration values of HR, SpO2 and VT. A obvious reduction of MAP appeared in the groups of C1 and C2, but in the other groups the hemodynamical parameters were stable. The groups of C1, C2 and S + C showed significant increase in VAS and VRS, along with increase of ePDT when compared with the pre-drug level. There was no obvious alteration in group S after the drug administration. It was concluded that (1) single use of sumatriptan is ineffective in the dose given in this study; (2) small dose (150 micrograms and 75 micrograms) of clonidine has epidurally analgesic effects; (3) combined use of sumatriptan and clonidine is an acceptable way in epidural analgesia, in terms of its analgesic effect and hemodynamic changes.  相似文献   
994.
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   
995.
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   
996.
The targeting of karyophilic proteins to nuclear pores is mediated via the formation of a nuclear pore-targeting complex, through the interaction of nuclear localization signal (NLS) with its NLS receptor. Recently, a novel human protein, Qip1, was identified from a yeast two-hybrid system with DNA helicase Q1. This study demonstrates that Qip1 is a novel third class of NLS receptor that efficiently recognizes the NLS of the helicase Q1. Moreover, the data obtained in this study show that the specific interaction between Qip1 and the NLS of the helicase Q1 requires its upstream sequence of the minimal essential NLS. By using purified recombinant proteins alone in the digitonin-permeabilized cell-free transport system, it was demonstrated that the two known human NLS receptors, Rch1 and NPI-1, are able to transport all the tested NLS substrates into the nucleus, while Qip1 most efficiently transports the helicase Q1-NLS substrates, which contain its upstream sequence in so far as we have examined the system. Furthermore, in HeLa cell crude cytosol, it was found that endogenous Rch1 binds to all the tested NLS substrates, while the binding of endogenous NPI-1 is restricted to only some NLSs, despite the fact that NPI-1 itself shows binding activity to a variety of NLSs. These results indicate that at least three structurally and functionally distinct NLS receptors exist in the human single cell population, and suggest that the nuclear import of karyophilic proteins may be controlled in a complex manner at the NLS recognition step by the existence of a variety of NLS receptors with various specificities to each NLS.  相似文献   
997.
We report 34 cases of tsutsugamushi disease seen from 1989 to 1993 at Yagi Clinic, northern Osumi, Kagoshima Prefecture. Nineteen patients (55.9%) showed the highest antibody titers against the Kawasaki strain Orientia tsutsugamushi (Ot) and 13 (38.2%) against the Kuroki strain Ot. It is suggested that two antigenic types (Kawasaki and Kuroki) of Ot were distributed in Kagoshima Prefecture, and the Kawasaki type Ot more or less dominates Kuroki type Ot. There was no difference in clinical features between the two groups of patients.  相似文献   
998.
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   
999.
Kim  H.Y. 《Electronics letters》1997,33(4):286-287
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   
1000.
Most of the previous treatments of semiconductor lasers subject to optical feedback from a phase-conjugate mirror (PCM) have assumed that the PCM responds instantaneously. Furthermore, the mechanism responsible for phase conjugation does not usually enter into the analysis. In this paper, we derive the time-dependent reflectivity of a PCM created through nondegenerate four-wave mixing in a Kerr-type nonlinear medium. The resulting laser dynamics are compared with the case of the ideal PCM, as a function of the external-cavity length, the PCM reflectivity, and the PCM interaction depth. The PCM with a significant interaction depth tends to suppress otherwise chaotic output and produces pulses whose repetition rate is tunable by varying PCM reflectivity. At high feedback levels, it stabilizes the laser output. We use the circle-map formalism to explain our numerical results  相似文献   
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