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排序方式: 共有6296条查询结果,搜索用时 31 毫秒
51.
Primm BJ Perez L Dennis GC Benjamin L Clark W Keough K Leak WD Payne R Smith D Sullivan LW;National Medical Association 《Journal of the National Medical Association》2004,96(9):1152-1161
ISSUE: Inadequate pain management is a serious public health problem that affects a wide cross-section of Americans. Patients are often denied sufficient medication, because physicians lack training and fear scrutiny from federal and state regulatory agencies. In addition, even the state-financed system of care, Medicaid, has been increasingly denying payment for the best treatment for pain management. These factors are complicated by physician bias about various subgroups and poor physician-patient communication. Comprehensive patient assessment plays a crucial role in determining appropriate treatment and identifying potential abuse problems. Physicians must routinely document medications analgesic effects and screen for potential ill effects and drug abuse. OBJECTIVE: To examine the prevalence of the undertreatment of pain, particularly among African Americans, and to recommend relevant proactive policy and practice changes to aid in eliminating this health problem. CONSENSUS PROCESS: In July 2002, the NMA convened the "Managing Pain: The Challenge in Underserved Populations: Appropriate Use versus Abuse and Diversion" Consensus Meeting in Washington, DC. The country's most renowned experts in the area of pain management and substance abuse reviewed substantial information regarding pain management and substance abuse including the following: --A draft summary paper on pain management and substance abuse that served as briefing material for consensus members; --Annotated bibliographies; --Articles on pain management and substance abuse; and --Key presentations on pain management and substance abuse. 相似文献
52.
Margaret A. MacNeil Stephen G. Lomber Bertram R. Payne 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,113(1):24-32
We investigated the constancy and variability in the numbers of thalamic and cortical neurons projecting to cat middle suprasylvian
(MS) visual cortex. Retrograde pathway tracers were injected at a single anatomically and physiologically defined locus in
MS cortex. Counts of labeled neurons showed that the visual thalamic projections to MS cortex consistently arose from a fixed
set of nuclei in relatively constant proportions. In contrast, counts of cortical neurons revealed that transcortical inputs
to MS cortex were much more variable. This differential variability may be linked to the developmental program, which affords
greater influence of experiential factors on cortical pathway development than on thalamocortical pathway development. These
results have implications for the development of models of cerebral connectivity that include measures of pathway variability.
Received: 29 March 1996 / Accepted: 3 September 1996 相似文献
53.
Claire M. Payne Raymond B. Nagle Samuel H. Paplanus Anna R. Graham Martin M. Berman 《Ultrastructural pathology》1986,10(6):539-552
Immunohistochemical and ultrastructural findings in two cases of fibrolamellar carcinoma of the liver and two cases of hepatocellular carcinoma of the common histologic type are described. Ultrastructural examination of both cases of fibrolamellar carcinoma revealed the presence of neurosecretory (NS) granules which were sparse in some cells and abundant in others. Many of the tumor cells had a distinct oncocytic appearance with abundant mitochondria. A portion of the glutaraldehyde-fixed neoplasm was processed for the uranaffin reaction (an ultrastructural cytochemical stain specific for the NS granules of neuroendocrine tissue). Abundant uranaffin-positive granules were found in the neoplastic cells of both cases of fibrolamellar carcinoma, whereas no uranaffin-positive granules were found in hepatocellular carcinoma of the common histologic type. There was no statistical difference in the mean diameter of the uranaffin-positive granules measured from both cases. Immunohisto-chemistry revealed the presence of neuron-specific enolase (NSE) and serotonin in one of the two cases of fibrolamellar carcinoma and no NSE staining in two cases of hepatocellular carcinoma of the common histologic type. These findings suggest that some liver tumors presenting histologically as fibrolamellar carcinoma may be neuroendocrine in nature. 相似文献
54.
Mnemonic coding system for clinical data entry into laboratory computers: its effect on quality and efficiency. 下载免费PDF全文
I R Bailey K B Page R G Jones R B Payne A J Little 《Journal of clinical pathology》1991,44(12):1018-1021
A simplified coding method for entering the clinical details found on pathology request cards was developed. The method uses a basic four letter code, derived from the initial character of the first four words in a clinical detail, being expanded to four characters with letters from the final word if the number of words is less than four. Rules were devised to cope with common medical terminology. In excess of 90% of clinical details on request cards are readily input by clerical staff using our coding system, and 8% of clinical details are used intelligently by the computer in scheduling further tests or automatically commenting on results. A carefully designed coding system such as the one outlined above could greatly facilitate input of clinical detail without the penalty of reduced throughput. 相似文献
55.
56.
Telfer JF; Thomson AJ; Cameron IT; Greer IA; Norman JE 《Human reproduction (Oxford, England)》1997,12(10):2306-2312
Superoxide, an agent which attenuates the half-life of nitric oxide, is
metabolized and synthesized by superoxide dismutase (SOD) and xanthine
oxidase, respectively. Over the last few years much work has focused on the
role of nitric oxide in human parturition. The aim of this study was to
determine whether the onset of human parturition is associated with a
change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD),
manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the
uterus. Samples of myometrium, placenta, decidua and fetal membranes were
obtained from women before and after the onset of labour at term.
Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine
oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like
immunoreactivity was detected in syncytiotrophoblast cells, villous stromal
cells and endothelial cells of blood vessels in the placenta. In the
myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial
cells and to some vascular smooth muscle cells. In the fetal membranes we
observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion,
extravillous trophoblast and decidua. There was no difference in SOD enzyme
activity or staining intensity for SOD between different cell types before
and during labour. Xanthine oxidase immunoreactivity was identified in each
of the tissues examined and again there was no difference in immunostaining
in tissues obtained from women delivered before or after the onset of
labour. These results show that the pregnant uterus is capable of both
synthesizing and degrading superoxide and suggest that superoxide dismutase
and xanthine oxidase may play a role in the maintenance of uterine
quiescence during pregnancy, but not in the initiation of parturition.
相似文献
57.
58.
The polypeptide composition of vaccinia-infected cell membranes and rifampicin bodies 总被引:1,自引:0,他引:1
The protein and glycoprotein composition of a sucrose gradient fraction from vaccinia infected cells treated with rifampicin was studied. This particulate fraction contained cytoplasmic membranes and pleomorphic membranous structures. The glycoproteins (89, 42 and 20-23 kDa, respectively) were identified as the same glycoproteins that are found in plasma membranes of infected cells and the envelope of extracellular enveloped vaccinia (EEV). These glycoproteins could be solubilized by 0.1% NP-40. The Golgi membrane associated 41K acylated vaccinia protein was also NP-40 soluble. In contrast, most particulate fraction proteins (125, 100, 86, 65, 41, 39, 31, 27, 25, 14 and 12.5 kDa) with the exception of the 33 and 29 kDa proteins remained essentially insoluble after NP-40 treatment. The 86 and 65 kDa proteins are the rifampicin inhibited precursors to INV core proteins while the 33 and 29 kDa proteins are INV surface proteins. Twelve proteins behaved like their respective comigrating INV proteins when extracted with NP-40 and 2ME. Electron microscopy showed that a centrifuged sediment from NP-40 treated cells contained pleomorphic protein containing membranous structures that we have called rifampicin bodies. We conclude that (1) the major glycoproteins found in the particulate fraction from sucrose gradients are vaccinia glycoproteins residing in cytoplasmic membranes while (2) the major non-glycosylated proteins are components of the rifampicin bodies and that (3) the rifampicin bodies represent an intermediate in the morphogenetic process leading to mature INV. 相似文献
59.
Lomber SG Payne BR Hilgetag CC Rushmore J 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,142(4):463-474
A contralateral hemineglect of the visual field can be induced by unilateral cooling deactivation of posterior middle suprasylvian (pMS) sulcal cortex of the posterior parietal region, and this neglect can be reversed by additional cooling deactivation of pMS cortex in the opposite hemisphere. The purpose of the present study was to test whether an enduring hemianopia induced by removal of all contiguous visual cortical areas of one hemisphere could be reversed by local cooling of pMS cortex in the opposite hemisphere. Two cats sustained large unilateral ablations of the contiguous visual areas, and cooling loops were placed in the pMS sulcus, and in contact with adjacent area 7 or posterior ectosylvian (PE) cortex of the opposite hemisphere. In both instances cooling of pMS cortex, but neither area 7 nor PE, restored a virtually normal level of orienting performance to stimuli presented anywhere in the previously hemianopic field. The reversal was highly sensitive to the extent of cooling deactivation. In a third cat, cooling deactivation of the superficial layers of the contralateral superior colliculus also restored orienting performance to a cortical ablation-induced hemianopia. This reversal was graded from center-to-periphery in a temperature-dependent manner. Neither the cortical ablation nor any of the cooling deactivations had any impact on an auditory detection and orienting task. The deactivations were localized and confirmed by reduced uptake of radiolabeled 2-deoxyglucose to be limited to the immediate vicinity of each cooling loop. The results are discussed in terms of excitation and disinhibition of visual circuits. 相似文献
60.
The sciatic nerve was crushed in the right hindlimb in newborn (3-8 h old) rats. Two to four months later, electromyographic activity was recorded from both the control and reinnervated ankle extensor muscles soleus or lateral gastrocnemius and from the ankle flexor muscle tibialis anterior. Tonic postural activity was present in the extensor muscles on both sides during quiet stance. The control flexor muscles were usually silent in this situation, but the reinnervated flexors exhibited abnormal sustained activity. During locomotion, the control extensors were activated during the stance phase and their mean burst made up 61.5% of the step cycle. The control tibialis anterior muscle fired only during the swing phase, with the burst lasting 18.1% of the step cycle. In the reinnervated extensor muscles, the mean burst duration was decreased (46% of the cycle) but the basic locomotor pattern was not impaired. The reinnervated tibialis muscle, however, was activated abnormally, with one appropriate flexor burst during the swing phase and an "extensor-like" burst during the stance phase of the step. Reflex responses to stretch were weak or absent on the operated side. Histological examination showed that the reinnervated soleus and tibialis muscles were almost devoid of muscle spindles. The motor unit mean firing rates in the reinnervated soleus (22 imp/s) and lateral gastrocnemius (45 imp/s) matched those of the control muscles (25 and 42 imp/s, respectively). In contrast to the phasic, high-frequency firing (52-80 imp/s) in the control tibialis, the reinnervated tibialis motor units fired at significantly lower rates (22-56 imp/s).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献