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The purpose of this study was to examine the effects of object self-stimulation on the task-interrupting self-stimulatory behavior and prevocational work responses of a 13-year-old autistic boy. Using a multiple-baseline design across three diferent prevocational tasks, a systematic manipulation of object self-stimulation was associated with increases in correct rates and decreases in task-interrupting self-stimulatory behaviors. An analysis of these data indicates that self-stimulatory behavior may be shaped to facilitate performance proficiencies. Social validation information suggests that favorable generalized responding had occurred. On the basis of findings from this study, future research needs are discussed.  相似文献   
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Metabolic fate of 125I-labeled batroxobin in rats and dogs   总被引:1,自引:0,他引:1  
125I-Labeled batroxobin was prepared and following its intravenous and subcutaneous administrations to rats and dogs, the blood radioactivity was determined. In the both species following the intravenous injections, the decrease in radioactivity was biexponential. Following subcutaneous administration, radioactivity became maximal at 6h and decreased in a manner similar to that of the beta-phase of the intravenous injection. The blood concentration of fibrinogen in dogs was also determined. After the intravenous injection, fibrinogen became undetectable 1h later, and appeared again in the blood at 24h. After the subcutaneous injection, the decrease was not so rapid. Fibrinogen resumed its original levels at 7 day after the administration in both the routes. Radioactivity after the both injections was excreted generally in the urine in about the same amounts. The total urinary and fecal excretions in rats and dogs were 80 and 95%, respectively. The distribution of radioactivity in the tissues was examined by counting technique and whole-body autoradiography. Radioactivity predominantly accumulated in the thyroid and stomach and could also be found in the kidneys and liver in fair amounts. The distribution patterns of radioactivity for both the routes of administrations and also for male and pregnant rats were basically the same. In fetus rats, a slight distribution was noted. From the results of gel filtration chromatography and trichloroacetic acid fractionation, [125I] batroxobin was metabolized soon after the administration to afford low molecular substances such as 125I-ion in the plasma and urine.  相似文献   
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Exfoliative toxin D (ETD) was identified recently as a new exfoliative toxin serotype. Like other exfoliative toxins, ETD induces intra-epidermal cleavage through the granular layer of the epidermis of neonatal mice. The distribution of ETD production was investigated in Staphylococcus aureus isolates from infected and colonised patients in France. The etd gene was found in 55 (10.5%) of 522 isolates tested. Isolates responsible for bullous impetigo and generalised staphylococcal scalded skin syndrome did not harbour etd, but etd was significantly more frequent in isolates causing cutaneous abscesses and furuncles. Most etd- and Panton-Valentine leukocidin-positive strains belonged to the clone of community-acquired methicillin-resistant S. aureus spreading currently throughout France.  相似文献   
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The pharmacokinetics of pipecuronium bromide was studied in 9 male patients (ASA class 1-2, 20-65 years of age). Following a single intravenous dose of pipecuronium 0.08 mg.kg-1, plasma levels were measured by capillary gas chromatography. Plasma concentration-time curves were evaluated by fitting the data to a bi-exponential equation. The pharmacokinetic parameters of pipecuronium were compared with those of pancuronium (0.08 mg.kg-1) and vecuronium (0.08 mg.kg-1) previously obtained under the same anesthesia (66% N2O, 33% O2 and 1% halothane). With pipecuronium, following pharmacokinetic parameters were obtained; distribution half-life; T1/2 alpha = 3.9 +/- 0.7 min (mean +/- SEM), elimination half-life; T1/2 beta = 102 +/- 12 min, volume of the central compartment; V1 = 95 +/- 13 ml.kg-1, volume of distribution at steady state; Vdss = 264 +/- 41 ml.kg-1, clearance; Cl = 1.8 +/- 0.2 ml.min-1.kg-1. Microconstants of two-compartment open models (k12, k21, k10) were also calculated. Using Mann-Whitney's U-test, these parameters of pipecuronium were compared with those of pancuronium (n = 3) and vecuronium (n = 4). V1 and Vdss of pipecuronium were significantly larger than those of pancuronium (V1; 38 +/- 12 ml.kg-1 and Vdss; 120 +/- 4 ml.kg-1) (both P less than 0.10). Reflecting the larger central volume of pipecuronium, pipecuronium tended to have a larger clearance than that of pancuroniumu (Cl; 1.1 +/- 0.2 ml.min-1.kg-1).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
6.
Over the past year, many reports have been published on a variety of clinical manifestations related to antiphospholipid antibodies. The low prevalence of anticardiolipin antibodies with the rare occurrence of thrombosis and a low rate of fetal loss in studies in Malaysia and China showed a potential role for local factors. A study of cross-reactive idiotype of the anticardiolipin antibody suggested that anticardiolipin antibodies are derived from a set of natural autoreactive clones. Regarding the pathogenic role of the antiphospholipid antibody, evidence has been presented that the epitopes formed between cardiolipin and beta 2 glycoprotein I are the targets of the antiphospholipid antibody. Complement activation, abnormalities of natural anticoagulants such as protein S deficiency, and genetic association with DR4, DR7, and DRw53 have also been studied.  相似文献   
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We report a metastatic pulmonary tumor resected by video-assisted thoracoscopic surgery. A 63-year-old female was found to have four nodules of hepatocellular carcinoma (HCC) in January 1991; after non-surgical treatment, the tumors had become necrotic. In June 1992, a new HCC nodule was found. After infusion chemotherapy, it became necrotic. In September 1993, a solitary lung tumor, 2.4 cm in diameter, appeared at the periphery of the right lung. Because the tumor was considered to be a metastatic HCC rather than a primary lung cancer, it was removed by thoracoscopic wedge resection. Although whether metastasectomy contributes to prolongation of survival is still controversial, thoracoscopic pulmonary resection may be indicated for solitary peripheral metastasis, if the primary HCC is well controlled by multidisciplinary treatment.  相似文献   
9.
The periarterial lymphoid sheath (PALS) in the rat spleen was studied by light, transmission, and scanning electron microscopy. The PALS was divided into three regions: the central region, peripheral region, and marginal zone bridging channel. In the central region, lymphocytes were easily washed away by perfusion. Large spaces were found between flat reticular cells or in large meshworks of stellate reticular cells; these may be deep lymphatic vessels. True lymphatic vessels were found in the central region near the hilus. In the marginal zone bridging channel, flat reticular cells surrounded the central artery in a circumferential pattern and formed channel-like spaces between the flat reticular cells. These spaces were connected with the meshwork of the red pulp reticular cells and may be a route for lymphocytes between the deep lymphatic vessels and the red pulp. In the peripheral region of the PALS, it was usually difficult to wash away free cells by perfusion, and free cells were found among the reticular cells. In places in the peripheral region, however, free cells were washed away. It is suggested that the lymph flow may start from the region surrounding the PALS, and that the peripheral region of the PALS may also be another route for lymphocyte migration.  相似文献   
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