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91.
Fifty-two case-hardened, severely self-abusive and aggressive autistic and retarded students, living in six different community residences, were trained to exit their residences, without the presence or assistance of staff, when a fire alarm sounded at night. On a pretest, prior to an 11-week period of intensive environmental and behavioral interventions, only 25% of the students exited within 2 1/2 minutes and independent of staff assistance. At posttest, 100% exited successfully, in a mean evacuation time of 60 seconds. The study was conducted at the Behavior Research Institute (BRI).  相似文献   
92.
Endogenous prostacyclin (PGI2; epoprostenol) is a potent endothelium-derived pulmonary vasodilator. However, the effects of exogenous PGI2 on isolated arteries could be either relaxant or contractile, depending on the species and organ studied. The present study investigated the distal pathways involved in the PGI2-induced contraction in rat intrapulmonary artery (PA) and relaxation in lamb PA. When vessels were precontracted with 30 mM K+, PGI2 (1 microM) induced relaxation in lamb PA but caused contraction in rat PA. Use of 30 mM K+, phenylephrine, serotonin, angiotensin II, or hypoxia to precontract the vessels did not alter the contractile effect of PGI2 in rat PA. Nevertheless, PGI2 produced a mild relaxation in rat PA precontracted by U-46619, a thromboxane A2 (TxA2)-receptor agonist, whereas the TxA2-receptor blocker SQ-29548 (0.1-0.5 microM) abolished the contractile response in rat PA. These data suggest that PGI2-induced contraction is mediated by activation of TxA2 receptors. The PGI2-induced modest relaxation in rat PA, which was only observed when TxA2 receptors were blocked by SQ-29548, suggests that the PGI2-mediated vasorelaxant pathway is diminished in these vessels. Simultaneous application of forskolin, an adenylate cyclase activator, and rolipram, a phosphodiesterase inhibitor, caused similar relaxation in both rat and lamb PA. This suggests that the adenosine 3',5'-cyclic monophosphate-dependent relaxing pathway is intact in rat PA and is comparable to that in lamb PA. On the basis of these data, we conclude that the pathways responsible for the paradoxical effects of PGI2 on rat and lamb PA are located upstream of the adenosine 3',5'-cyclic monophosphate-dependent relaxing pathway and that a paucity of PGI2 receptors in rat PA may be responsible.  相似文献   
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The rate of nosocomial respiratory syncytial virus (RSV) infection was measured in a large pediatric hospital using an incidence density method. The at-risk days for nosocomial RSV were summed during a defined winter period in which there were 54 admissions with community-acquired RSV infection giving a rate of 2.9 cases per 1,000 at-risk days (95% confidence interval, 0.3-5.4 per 1,000).  相似文献   
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Only 19 cases of metastases at the cannula insertion site after laparoscopy for gynecological malignancy have been reported in the literature. One case has been diagnosed with cervical squamous cell carcinoma, whereas the others have been diagnosed with ovarian cancer and borderline ovarian tumor. We present a novel case of laparoscopy-site abdominal wall metastasis from endometrial cancer after laparoscopic-assisted vaginal hysterectomy (LAVH). The 56-year-old female patient exhibited metastases of an abdominal wall trocar site and a perineal site after undergoing LAVH and laparoscopic-assisted (LA) bilateral pelvic lymph node sampling as well as LA para-aortic lymph node sampling for treating endometrial carcinoma, surgical staging IIIC, G3. The interval between the surgical extirpation of endometrial carcinoma and diagnosis of the tumor recurrence was 6 months, suggesting that overmanipulation of the diseased organ during laparoscopic surgery may have resulted in tumor spillage, intraperitoneal dissemination, and wound contamination. Although this procedure has been proven beneficial to patients with benign disease or early-stage gynecologic malignancies, laparoscopic-assisted vaginal hysterectomy may not be efficacious to eradicate advanced gynecological malignancy.  相似文献   
97.
Acute, monophasic experimental allergic encephalomyelitis (EAE) in the Lewis rat shows pathological similarities to the human disease multiple sclerosis (MS). Rats that recover from EAE are essentially resistant to disease reinduction, unlike MS in which relapses are frequently associated with common bacterial and viral infections. As macrophage-derived interleukin (IL)-12 is a critical component of innate resistance to bacterial infection and appears to directly activate encephalitogenic T cells in vivo, the ability of this cytokine to reinduce paralysis in EAE was examined. Paralytic disease was exacerbated by intraperitoneal IL-12 administration and could be reinduced up to 1 week after recovery from the primary clinical episode. Concomitant with worsening of initial clinical signs and relapse was an increase in the ratio of macrophages to T cells in brain stem perivascular cuffs and the expression of inducible nitric oxide synthase in cells with both macrophage and microglial morphology. These findings suggest that IL-12 may contribute to macrophage-mediated disease exacerbation and relapse in patients with MS.  相似文献   
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28 isolates of canine parvovirus type-2 (CPV-2) were obtained from dogs with hemorrhagic gastroenteritis in Italy. The antigenic structure of CPV-2 isolates was characterized, using four discriminating monoclonal antibodies. In addition, four vaccinal strains were examined. Similar to reports from Australia and the United Kingdom, a much higher prevalence of CPV-2a (25/28 isolates) was observed than the other variant type, CPV-2b (3/28 isolates). DNA fragments (2.2 kbp) of representative strains of CPV-2, CPV-2a and CPV-2b were amplified by the polymerase chain reaction (PCR) and the products were digested by the restriction enzymes (RE) RsaI, HpaII, HindIII and PvuII. The RvaI enzyme allows the differentiation of CPV-2 from CPV-2a and CPV-2b.  相似文献   
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