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11.
We performed transurethral resections of the prostate in 100 patients under local anesthesia supplemented when appropriate by intravenous medication. In the first part of the study (40 patients) local anesthesia was infiltrated into the prostate transurethrally only, while in the second part (60 patients) infiltration was performed transurethrally and perineally. Prostate sizes ranged from 5 to 50 gm., and pain control was excellent in the majority of the patients, especially when perineal infiltration was added to the procedure. Of the patients 98 per cent said they would do it again, no patient required conversion to general anesthesia and there were no significant complications relating to the anesthesia. Local anesthesia with intravenous supplementation can be performed successfully in the majority of the patients with small to moderately sized prostate glands. 相似文献
12.
Neuropathogenesis of Chimeric Simian/Human Immunodeficiency Virus infection In Pig-tailed and Rhesus Macaques 总被引:2,自引:0,他引:2
Ravi Raghavan Edward B Stephens Sanjay V Joag Istvan Adany David M Pinson Zhuang Li Fenglan Jia Manisha Sahni Chunyang Wang Kevin Leung Larry Foresman Opendra Narayan 《Brain pathology (Zurich, Switzerland)》1997,7(3):851-861
We recently reported that a chimeric simian/human immunodeficiency virus (SHIVKU-1 ) developed in our laboratory caused progressive depletion of CD4+ T lymphocytes and AIDS within 6 months of inoculation into pig-tailed macaques (M.nemestrina). None of the pig-tailed macaques showed productive SHIV infection in the central nervous system (CNS). In this report, we show that by further passage of the pathogenic virus in rhesus macaques [M. mulatta], we have derived a new strain of SHIV (SHIVKU-2 ) that has caused AIDS and productive CNS infection in 3 of 5 rhesus macaques infected with the virus. Productive replication of SHIV in the CNS was clearly shown by high infectivity titers and p27 protein levels in brain homogenates, and in 2 of the 3 rhesus macaques this was associated with disseminated, nodular, demyelinating lesions, including focal multinucleated giant cell reaction, largely confined to the white matter. These findings were reminiscent of HIV-1 associated neurological disease, and our immunohistochemical and in situ hybridization data indicated that the neuropathological lesions were associated with the presence of SHIV-specific viral antigens and nucleic acid respectively. However, the concomitant reactivation of opportunistic infections in these macaques suggested that such pathogens may have influenced the replication of SHIV in the CNS, or modified the neuropathological sequelae of SHIV infection in the rhesus species, but not in pig-tailed macaques. Our findings in the two species of macaques highlight the complexities of lentiviral neuropathogenesis, the precise mechanisms of which are still elusive. 相似文献
13.
Finite-element models of the human head 总被引:9,自引:0,他引:9
L. Voo PhD S. Kumaresan F. A. Pintar N. Yoganandan A. Sances Jr. 《Medical & biological engineering & computing》1996,34(5):375-381
A review is presented of the existing finite-element (FE) models for the biomechanics of human head injury. Finite element
analysis can be an important tool in describing the injury biomechanics of the human head. Complex geometric and material
properties pose challenges to FE modelling. Various assumptions and simplifications are made in model development that require
experimental validation. More recent models incorporate anatomic details with higher precision. The cervical vertebral column
and spinal cord are included. Model results have been more qualitative than quantitative owing to the lack of adequate experimental
validation. Advances include transient stress distribution in the brain tissue, frequency responses, effects of boundary conditions,
pressure release mechanism of the foramen magnum and the spinal cord, verification of rotation and cavitation theories of
brain injury, and protective effects of helmets. These theoretical results provide a basic understanding of the internal biomechanical
responses of the head under various dynamic loading conditions. Basic experimental research is still needed to determine more
accurate material properties and injury tolerance criteria, so that FE models can fully exercise their analytical and predictive
power for the study and prevention of human head injury. 相似文献
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Murine neurotropic retrovirus spongiform polioencephalomyelopathy: acceleration of disease by virus inoculum concentration. 总被引:4,自引:1,他引:4
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A 10-fold reduction in the incubation period of murine neurotropic retrovirus spongiform polioencephalomyelopathy was effected by a 1,000-fold concentration of the cloned virus inoculum. 相似文献
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M. M. Engelgau K. M. Narayan L. S. Geiss T. J. Thompson G. L. Beckles L. Lopez T. Hartwell W. Visscher L. Liburd 《Journal of the National Medical Association》1998,90(10):605-613
Project DIRECT (Diabetes Interventions Reaching and Educating Communities Together) is the first comprehensive community diabetes demonstration project in the United States in an African-American community. This article describes its intervention components and evaluation design. The development and implementation of Project DIRECT has included the community since the project''s beginning. Interventions are targeted in three areas: health promotion (improving diet and physical activity levels), outreach (improving diabetes awareness, detection of undiagnosed diabetes, and ensuring that persons with diabetes who are not receiving continuing diabetes care are integrated into the health-care system), and diabetes care (improving self-care, increasing access, and improving the quality of diabetes preventive care received within the health-care system). Evaluation will be internal (conducted by Project DIRECT staff to assess process outcomes in persons directly exposed to each specific intervention) and external (review of outcomes to assess the impact of the multi-intervention program at the level of the entire community). Because diabetes exacts a disproportionate toll among African Americans, the findings from this project should aid in developing strategies to lessen the burden of this disorder, particularly among minority populations. 相似文献
19.
Kumar S Ferrari R Narayan Y Vieira ER 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,167(3):345-351
The purpose of this study was to determine the response of the cervical muscles to increasing low-velocity, whiplash-type
lateral impacts when the occupant is seated out of the recommended driving position (neutral posture). Twenty healthy volunteers
were subjected to left lateral impacts of 4.1, 7.7, 10.5, and 13.7 m/s2 acceleration, with their trunk flexed by 45° and laterally flexed to the right and left also by 45° at the time of impact.
Bilateral electromyograms of the sternocleidomastoids, trapezii, and splenii capitis were recorded. Under these conditions
of trunk-flexed postures, in a left lateral impact, muscle responses were of generally low magnitude with the trunk flexed
to either the left or right. Even at the highest acceleration of 13.7 m/s2, all muscles generated less than 37% of their known maximal voluntary contraction electromyogram. Also, in these left lateral
impacts, the right splenius capitis showed a greater EMG response than the left splenius capitis regardless of whether the
subject was flexed to the right or left at the time of impact. The right splenius capitis (the one contralateral to the left
lateral impact direction) was more active than its counterpart. Compared to what is known for EMG responses with an occupant
in the neutral posture, the right sternocleidomastoid (usually the most active muscle in a left lateral collision) was significantly
less-active with trunk flexion than with neutral posture conditions (P<0.01). In the absence of bodily impact, the flexed trunk posture does not produce a biomechanical response that would increase
the likelihood of cervical muscle injury in low velocity lateral impacts, and may lessen the risk of injury for some muscles. 相似文献
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