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1.
Andy KH Lim 《World journal of gastroenterology : WJG》2020,26(10):1020-1028
Rhabdomyolysis is a syndrome of skeletal muscle injury with release of cellular constituents such as potassium,phosphate,urate and intracellular proteins such as myoglobin into the circulation,which may cause complications including acute kidney injury,electrolyte disturbance and cardiac instability.Abnormal liver function tests are frequently observed in cases of severe rhabdomyolysis.Typically,there is an increase in serum aminotransferases,namely aspartate aminotransferase and alanine aminotransferase.This raises the question of liver injury and often triggers a pathway of investigation which may lead to a liver biopsy.However,muscle can also be a source of the increased aminotransferase activity.This review discusses the dilemma of finding abnormal liver function tests in the setting of muscle injury and the potential implications of such an association.It delves into some of the clinical and experimental evidence for correlating muscle injury to raised aminotransferases,and discusses pathophysiological mechanisms such as oxidative stress which may cause actual liver injury.Serum aminotransferases lack tissue specificity to allow clinicians to distinguish primary liver injury from muscle injury.This review also explores potential approaches to improve the accuracy of our diagnostic tools,so that excessive or unnecessary liver investigations can be avoided. 相似文献
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3.
王伏虎 《南京医科大学学报(英文版)》2002,16(2):49-64
Stroke is a debilitating disease that affects millions each year.While in many cases cerebral ischemic in jury can be limited by effectivw resuscitation or thrombolytic treatment,the injured neurons wither in a process known as delayed neuronal death(DND).Mounting evidence indicates that DND is not simply necrosis played out in slow motion but apoptosis is triggered.Of particular interest are two groups of signal proteins that participate in apoptosis-cyclin dependent kinases(CDKs) and p53-among a myriad of signaling events after an ischemic insult.Recent investigations have shown that CDKs,a family of enzymes initially known for their role in cell cycle regulation,are activated in injured neurons in DND.As for p53,new reports suggest that its up-regulation may represent a failed attempt to rescue in jured neurons,although its up-regulation was previously considered an indication of apoptosis.These observations thus rekindle an old quest to identify new neuroprotective targets to minimize the stroke damage.In this review,the author will examine the evidence that indicates the participation of CDKs and p53 in DND and then introduce pre-clinical data to explore CDK inhibition as a potential neuroprotective target.Finally,using CDK inhibition as an example,this paper will discuss the pertinent criteria for a viable neuroprotective strategy for ischemic in jury. 相似文献
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5.
Frank L Cole Laura L Kuensting Susan Maclean Cynthia Abel Joyce Mickanin Patty Brueske Mary Ellen Wilson Maureen Rehwaldt 《Journal of emergency nursing》2002,28(5):414-419
INTRODUCTION: Very little is known about clinical nurse specialists and nurse practitioners (advance practice nurses [APNs]) who practice in emergency care settings. The Advanced Practice Committee of the ENA sought to determine a profile of these individuals. METHODS: Surveys were distributed to all registrants at 2 ENA conferences and posted on the ENA Web site. This survey asked 17 questions concerning the demographic characteristics of the APN respondents (eg, education, experience, certification, state recognition, and practice area). The survey was completed by 166 APNs. RESULTS: APNs had considerable experience as ED registered nurses before becoming an APN. They obtained their APN education at the master's degree or post-master's degree level. State recognition was required for 89.2% of the APNs. The majority of APNs (61.4%) obtained their certification through the American Nurses Credentialing Center. Nurse practitioners were predominantly family nurse practitioners (43%), and clinical nurse specialists were either critical care clinical nurse specialists (8.9%) or had other certifications (5.9%). APNs provided services in both the main emergency department and the fast track (45.7%) and were relatively new to their role as an APN. DISCUSSION: Consistent with current educational and certification requirements, the vast majority of APNs held a master's degree. Although relatively new to their role as APNs in emergency care, they were nonetheless very experienced as ED registered nurses. The majority of APNs were certified, even though that is not required for practice in all states. Continued research is needed to identify the most effective utilization of APNs, document their contributions to patient care outcomes, and develop strategies to meet their educational and practice needs. 相似文献
6.
A model was developed which estimates the costs of osteoporosis risk evaluation and treatment, and the resulting savings in terms of reduced fracture frequency, for the adult female population of the United States. In the absence of treatment, the model predicts 1.44 million fractures will occur annually from non-violent causes. Treatment of all women beginning at age 50 with an agent that slows bone loss by 50% would reduce the number of these fractures by 0.59 million. Selective treatment of the 47% of women at the greatest fracture risk would reduce the number of fractures by 0.45 million, but would only cost 47% as much as treating all women. Additional data are required before the model can be used to evaluate specific treatment regimens. However, it appears that selective treatment of those at highest risk would yield the greatest benefit to cost ratio, if only benefits related to reduced fracture frequency are considered. 相似文献
7.
Effects of exercise training on men seropositive for the human immunodeficiency virus-1. 总被引:1,自引:0,他引:1
L W Rigsby R K Dishman A W Jackson G S Maclean P B Raven 《Medicine and science in sports and exercise》1992,24(1):6-12
We examined the effects of chronic exercise on fitness and immune status in Caucasian males (34.9 +/- 5.6 yr) diagnosed by Western blot as seropositive for the HIV-1 virus. The exercise regimen involved 12 wk of 1 h sessions 3 d.wk: 20 min of cycle exercise at 60-80% HRreserve was followed by 35 min of strength and flexibility training. After matching subjects on health status (modified Walter Reed criteria), subjects (N = 37) were randomly assigned to exercise or a counseling control condition. Changes in strength, responses to the YMCA cycle test, and serum lymphocytes were tested by MANOVA in a condition (exercise or counseling)-by-time (pretest, posttest) design with repeated measures on time. Results indicated significant (P less than 0.001) group-by-time interactions for strength (N.m) (chest press and leg extension) and for HR (beats.min-1) and total time (TT) on the cycle test at 150 W. Strength and TT increased and HR decreased in the exercise condition, while control subjects did not change. Total leukocyte, lymphocyte, CD4+, and CD8+ cell counts, and the CD4+/CD8+ ratio were statistically unchanged for each condition. We conclude that HIV-1+ men, including those symptomatic for AIDS-related complex, can experience significant increases in neuromuscular strength and cardiorespiratory fitness without changes in lymphocyte phenotypes or clinical diagnosis when the exercise regimen is prescribed and monitored in accordance with ACSM guidelines for healthy adults. 相似文献
8.
Androgen receptor YAC transgenic mice carrying CAG 45 alleles show trinucleotide repeat instability 总被引:1,自引:15,他引:1
La Spada AR; Peterson KR; Meadows SA; McClain ME; Jeng G; Chmelar RS; Haugen HA; Chen K; Singer MJ; Moore D; Trask BJ; Fischbeck KH; Clegg CH; McKnight GS 《Human molecular genetics》1998,7(6):959-967
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG
repeat expansion in the first exon of the androgen receptor (AR) gene.
Disease-associated alleles (37-66 CAGs) change in length when transmitted
from parents to offspring, with a significantly greater tendency to shift
size when inherited paternally. As transgenic mice carrying human AR cDNAs
with 45 and 66 CAG repeats do not display repeat instability, we attempted
to model trinucleotide repeat instability by generating transgenic mice
with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions
in their genomic context. Studies of independent lines of AR YAC transgenic
mice with CAG 45 alleles reveal intergenerational instability at an overall
rate of approximately 10%. We also find that the 45 CAG repeat tracts are
significantly more unstable with maternal transmission and as the
transmitting mother ages. Of all the CAG/CTG repeat transgenic mice
produced to date the AR YAC CAG 45 mice are unstable with the smallest
trinucleotide repeat mutations, suggesting that the length threshold for
repeat instability in the mouse may be lowered by including the appropriate
flanking human DNA sequences. By sequence-tagged site content analysis and
long range mapping we determined that one unstable transgenic line has
integrated an approximately 70 kb segment of the AR locus due to
fragmentation of the AR YAC. Identification of the cis - acting elements
that permit CAG tract instability and the trans -acting factors that
modulate repeat instability in the AR YAC CAG 45 mice may provide insights
into the molecular basis of trinucleotide repeat instability in humans.
相似文献
9.
Wilson R Moore J Jenkins C Miller H Maclean MA McInnes IB Walker JJ 《Human reproduction (Oxford, England)》2003,18(7):1529-1530
BACKGROUND: Immunological abnormalities have been found in pregnant women with a history of recurrent miscarriage. This study compared interleukin-2 receptor (IL-2R) levels in non-pregnant women with a history of recurrent miscarriage with those found in serum from a non-pregnant group with no such history. METHODS: Group 1 comprised 49 non-pregnant women with a history of recurrent miscarriage (at least three consecutive miscarriages). Group 2 comprised 22 non-pregnant women with no history of miscarriage. Serum IL-2R levels were measured in all patients. RESULTS: The results obtained showed that although all women were not pregnant at the time of sampling, IL-2R levels were significantly higher in women in Group 1 compared with those in Group 2 (1589 +/- 1289 versus 1082 +/- 823 pg/ml; P < 0.05). Follow-up data were available for 21 women from Group 1. The next pregnancy ended successfully for 14 of these women, while seven miscarried again. The IL-2R levels obtained pre-pregnancy were not significantly different between the two groups (1480 +/- 910 versus 1356 +/- 716 pg/ml). CONCLUSION: This study has shown that non-pregnant women with a history of recurrent miscarriage have raised IL-2R levels. These increased pre-pregnancy IL-2R levels did not necessarily predict miscarriage for the next pregnancy. 相似文献
10.
N E Morton D C Rao H Lang-Brown C J Maclean R D Bart R Lew 《Journal of medical genetics》1977,14(1):1-9
This reanalysis of a classic survey leads to inferences about design of genetic studies, resolution of heterogeneity, and the role of autosomal and sex-linked genes in mental retardation, which is no longer refractory to segregation analysis. By discriminating between sociofamilial and biological types we estimate that at least 351 autosomal loci can produce mental retardation, with an inbred load of 0.83 detrimental equivalents and a mutation rate of 0.008 per gamete, or less than 2.4 X 10(-5) per locus. The distribution of probands was estimated as: 7 per cent medical, 60 per cent sociofamilial, and 33 per cent biological. Simple genetic mechanisms account for virtually all the biological category. Within the sociofamilial group cultural inheritance and polygenes could not be resolved. 相似文献