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991.
H Ren RS Poston RH Hruban WA Baumgartner KL Baughman GM Hutchins 《Canadian Metallurgical Quarterly》1993,6(4):402-407
Several aspects of giant cell myocarditis remain controversial, including the natural history of the disease and the nature of the giant cells. We have observed three patients who had long survival with chronic active giant cell myocarditis. The first patient was a 59-yr-old female who had a 10-yr history of complete heart block which was found at autopsy to have been caused by giant cell myocarditis. The second patient is a 36-yr-old female who received a heart transplant 5 yr after a biopsy proven episode of active myocarditis, and examination of the explanted heart revealed giant cell myocarditis. The third patient was a 41-yr-old male who received a heart transplant 2 yr after developing progressive heart failure, and the explanted heart had giant cell myocarditis. On immunohistochemical study of the three hearts, the giant cells stained with the macrophage markers lysozyme and KP-1 (CD-68). Staining of the same cells with desmin and actin was focally positive in a punctate pattern, correlating with the ultrastructural presence of myofibrils within giant cell phagolysosomes. The associated lymphocytic infiltrate stained primarily for the T-cell markers CD-3, CD-45RO, and CD-43 whereas only a few of the lymphocytes stained with the B-cell marker CD-20. The long histories of cardiac dysfunction in the three patients show that giant cell myocarditis may have a protracted course. The morphologic studies show that the giant cells are of histiocytic origin but can contain phagocytosed components of myocytes, observations that may account for the controversy surrounding the nature of the giant cells in giant cell myocarditis. 相似文献
992.
The enzyme aspartate aminotransferase (AAT) currently is used to identify Anopheles quadriannulatus Theobald, the animal-biting, nonmalaria vector species of the Anopheles gambiae complex. Samples of An. quadriannulatus from South Africa and An. gambiae Giles s.str. from the island of Grand Comoros and the People's Republic of Congo have shown variation in electromorph frequencies that indicate that AAT has five alleles. The three slowest alleles are found in An. quadriannulatus and the three fastest in An. gambiae, An. arabiensis Patton and An. merus D?nitz. One of these is common to both An. quadriannulatus and An. gambiae. This overlap indicates a potential misidentification of 0.3% of unknown females with a further 2.1% being unidentifiable. However, all of the specimens in the overlap area were classified correctly using octanol dehydrogenase (ODH). Variation at the ODH locus in An. quadriannulatus is recorded for the first time, with four of 157 specimens being heterozygous for the fast allele. The probability of both AAT and ODH giving an incorrect or indecisive identification is 0.0005. The slowest AAT alleles were present in samples from a single locality, indicating the lack of gene flow between subpopulations of An. quadriannulatus in close geographic proximity in the Shingwedzi area, South Africa. A modified method for multiple gel casting is given. 相似文献
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995.
I Bruck SA Antoniuk FB da Cunha RT Gon?alves GI Hamamoto RH Scola LC Werneck 《Canadian Metallurgical Quarterly》1996,54(4):683-686
We describe a lumbosacral plexus neuropathy case in childhood in which detailed investigation, including electromyography and magnetic resonance imaging, was normal. Muscle biopsy showed mild denervation. No underlying condition was detected. The patient presented with pain, weakness and light atrophy in left lower limb, reduced reflex at the ankle, loss of the quadriceps reflex and paresthesy in involved limb. Recovery after one year was almost complete, with persistent slight weakness and atrophy. 相似文献
996.
Although a limited number of drugs make up the mainstay of treatment of endometriosis, many alternative medications have been used in an attempt to improve efficacy. Some have been rigorously evaluated and are of proven benefit, while others show promise in preliminary trials or in animal models. Proper methods of evaluating medical therapy and outcomes are essential. This chapter provides a review of new medical therapies for the treatment of endometriosis and their evaluation. 相似文献
997.
To optimize the performance of off-road bicycle suspension systems, a dynamic model of the bicycle/rider system would be useful. This paper takes a major step toward this goal by developing a dynamic system model of the cyclist. To develop the cyclist model, a series of four vibrational tests utilizing random inputs was conducted on seven experienced off-road cyclists. This allowed the transfer functions for the arms and legs to be determined. To reproduce the essential features (i.e., resonance peaks) of the experimental transfer functions, the system model included elements representing the visceral mass along with the arms and legs. Through simulations, the frequency responses of the system model of the rider in each of the four tests were computed. Optimal stiffness and damping parameter values for each subject were determined by minimizing the difference between the experimental and simulation results. Good agreement between experimental and simulation results indicates that modeling the rider as a lumped parameter system with linear springs and dampers is possible. 相似文献
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999.
Recent interest in case management by elementary and secondary schools has arisen out of a growing recognition that schools alone are not prepared to address the myriad of health, education, and social service needs of a large number of students, particularly children living in poverty. Boys and girls entering classrooms hungry, sick, homeless, or otherwise distracted are not ready to learn. Improving readiness to learn is a major agenda among educators. Case management is one approach many schools are beginning to use to collaboratively engage parents, community service agencies, the private sector, and communities at large in pursuit of the goal. A promising school-based case management model has been developed and successfully field tested by the University of Washington. The model operationally defines case management, delineates a delivery structure, and includes an evaluation design. Results from a five-year study sponsored by the U. S. Department of Education are encouraging. Although several challenges persist, the future for school case management use is optimistic. Several enhanced variations of the Center for the Study and Teaching of At-Risk Students (C-STARS) case management model are now being demonstrated across the country. 相似文献
1000.
Selective serotonin reuptake inhibitors are useful in the treatment of posttraumatic stress disorder (PTSD), but have a number of side-effects which limit their acceptability. A newer serotonergic compound, nefazodone, has a different side-effect profile, thus making it a potentially promising compound to study. Seventeen private practice patients with PTSD were treated with nefazodone up to 600 mg/day for a maximum total treatment period of 12 weeks. All subjects were civilians, and were monitored for efficacy and side-effects at weeks 1, 2, 4, 6, 8 and 12. Nefazodone was associated with statistically significant improvement in mean scores on all six rating scales used to assess change from baseline in PTSD symptoms. Additionally, statistically significant improvement from baseline were seen for the intrusive, avoidant/numbing, and hyperarousal clusters on a global PTSD scale. Early improvements in nightmares and general sleep disturbance were observed. Overall, there was a 43% response rate at endpoint, or 60% in treatment completers, by observer rating. Side-effects (assessed on the Medication Effects Scale) were generally benign. Nefazodone was associated with clinical improvement in this population, and now needs to be studied in double-blind, placebo controlled, protocols. 相似文献