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81.
Venous clots: evaluation with MR imaging 总被引:2,自引:0,他引:2
In vitro and in vivo studies were performed to determine the proton relaxation and imaging characteristics of static blood and acute and organized clot in canine jugular veins. In vivo, it was found that two inversion recovery sequences using a short inversion time (100 msec) demonstrated better differentiation of signal intensity of intravascular clot from surrounding soft tissues than did standard T1- and T2-weighted sequences. In vitro, quantitative measurements showed marked reduction of both T1 and T2 relaxation time of acute clot compared with stagnant blood. In addition, the T1 relaxation time, and to a lesser extent the T2 relaxation time, shortened as the clot aged, indicating a potential role for magnetic resonance imaging in determining the age of venous thrombi. 相似文献
82.
83.
Gary Michael Dobson MD CM Dr Brian F. Horan MB BS Neil Thomas Bradburn MB BS 《Journal of clinical monitoring and computing》1992,8(1):62-65
We describe a patient undergoing elective surgery for treatment of an abdominal aortic aneurysm in whom an abrupt change in the contour of the pulmonary artery pressure (PAP) trace indicated the development of an intermediate (20 mm Hg) V wave in the pulmonary artery wedge pressure (PAWP) trace. As the PAP trace is displayed continuously, attention to its contour may allow for early detection of changes to the underlying PAWP trace.FC Anaesth 相似文献
84.
Trichinella infection and clinical disease 总被引:1,自引:0,他引:1
Clausen MR; Meyer CN; Krantz T; Moser C; Gomme G; Kayser L; Albrectsen J; Kapel CM; Bygbjerg IC 《QJM : monthly journal of the Association of Physicians》1996,89(8):631-636
Trichinellosis is caused by ingestion of insufficiently cooked meat
contaminated with infective larvae of <it>Trichinella</it>
species. The clinical course is highly variable, ranging from no apparent
infection to severe and even fatal disease. We report two illustrative
cases of trichinellosis. Returning to Denmark a few days after having eaten
roasted pork in the Republic of Serbia, a female patient suffered from
severe vomiting, epigastric pain, diarrhoea, and later myalgia, generalized
oedema, and prostration. A biopsy showed heavy infestation with
<it>Trichinella spiralis</it>, 2000 larvae/g of muscle.
Life-threatening cardiopulmonary, renal and central nervous system
complications developed. The patient recovered after several months. Her
husband, who also ate the pork, did not have clinical symptoms, but an
increased eosinophil count and a single larva in a muscle biopsy confirmed
infection. The epidemiology, clinical manifestations, diagnosis, treatment
and prevention of trichinellosis are reviewed.
相似文献
85.
86.
Autoantibodies against bactericidal/permeability-increasing protein in patients with cystic fibrosis 总被引:5,自引:0,他引:5
Zhao MH; Jayne DR; Ardiles LG; Culley F; Hodson ME; Lockwood CM 《QJM : monthly journal of the Association of Physicians》1996,89(4):259-265
Cystic fibrosis (CF), a genetic disorder, is characterized by chronic
pulmonary infection/inflammation which leads to respiratory failure. The
presence of anti-neutrophil cytoplasmic autoantibodies (ANCA) has
previously been observed in the sera of patients with CF. In view of the
known relationship of ANCA with primary vasculitis and of their putative
pathogenetic role in these disorders, we studied the presence, specificity
and isotype of ANCA and their clinical associations in 66 adult CF
patients. None of the 66 CF samples had autoantibodies to the major ANCA
antigens, proteinase 3 or myeloperoxidase. However, 60/66 (91%) CF samples
contained IgG and 55/66 (83%) IgA, autoantibodies to
bactericidal/permeability increasing protein (BPI), a recently
characterized ANCA specificity. All the IgA anti-BPI-positive samples were
also IgG anti-BPI-positive. The autoantibody specificity was confirmed by
inhibition assay and immunoblotting of CF sera against a neutrophil granule
preparation. Furthermore, in this cross-sectional study, anti-BPI levels
were inversely correlated with the observed reductions in FEV1 and FVC (IgA
anti-BPI and FEV1: r = 0.508, <it>p</it> < 0.0001), and
both IgG and IgA anti-BPI levels were higher in CF patients with secondary
vasculitis (<it>n</it> = 6) than in those without
(<it>p</it> < 0.05). ANCA with specificity for BPI were
present in the majority of CF sera in this study and autoimmune processes
may be associated with the development of pulmonary injury in CF.
相似文献
87.
Kidney transplants in mice. An analysis of the immune status of mice bearing long-term, H-2 incompatible transplants 下载免费PDF全文
Kidney transplants between strains of mice which are incompatible at either the K or the D end of the H-2 complex usually function for prolonged periods supporting the lives of nephrectomized recipients. This occurs with no recipient treatment. With multiple H-2 and non-H-2 determined incompatibilities, transplants may be rejected but more slowly than skin grafts. In the strain combination studied most extensively in these experiments (B10.D2 to B6AF(1)) in which the incompatibility was confined to the K end of the H-2 region, about 70 percent of recipients survived for many weeks with normal blood urea nitrogen levels. Skin grafts between untreated members of these strains were rejected promptly (mean survival time of 13.5 +/- 1.1 days) as were kidney transplants to recipients of prior skin grafts. Donor strain skin grafts to recipients of kidney transplants after kidney transplantation enjoyed greatly prolonged survival whereas skin grafts from a third party (A.SW) were rejected normally. If kidney tissue was transferred in the form of free grafts without primary vascular union, it was rejected promptly leaving its recipient highly immunized. Cellular and humoral immunity to donor antigens declined over the first few weeks after transplantation, and the spleens of long-term recipients contained no “killer cells.” Recipient lymphoid cells could mount active graft versus host reactions to donor strain antigens on transfer to neonatal mice. Nevertheless, they were distinctly less able to respond specifically by the production of killer cells to donor strain antigens after sensitization in vitro. No evidence that this defect was associated with the presence of suppressor cells was forthcoming from several types of in vivo and in vitro tests. 相似文献
88.
白藜芦醇对动物离体心房收缩力和心率作用的种属差异性比较 总被引:1,自引:0,他引:1
目的:观察白藜芦醇对豚鼠、小鼠和家兔离体心肌收缩力和心率的影响。方法:实验于2005-08/2006-12在河北医科大学西校区实验中心完成。①实验分组:离体豚鼠、小鼠和家兔心肌各分为9组:空白对照组、溶剂对照组、递增累积浓度白藜芦醇组(浓度为10-6,3×10-6,10-5,3×10-5,10-4,3×10-4mol/L),白藜芦醇对照组(5×10-5mol/L),ATP敏感性钾通道阻断剂格列苯脲(5×10-5mol/L)预孵育 白藜芦醇组,钙激活钾通道阻断剂四乙胺(10-3mol/L)预孵育 白藜芦醇组,电压依赖性钾通道阻断剂4-氨基吡啶(10-3mol/L)预孵育 白藜芦醇组,内向整流钾通道阻断剂氯化钡(10-4mol/L)预孵育 白藜芦醇组,乙酰胆碱调节钾通道阻断剂阿托品(10-5mol/L)预孵育 白藜芦醇组。②实验方法:不同类型的钾通道阻断剂均预孵育15min后,分别加入白藜芦醇(终浓度为5×10-5mol/L),连续记录30min,与相应动物白藜芦醇对照组相比较。③评估指标:分析不同阻断剂与白藜芦醇联用对心房收缩力下降率及心率抑制率的影响。结果:①白藜芦醇可降低豚鼠和小鼠离体心肌收缩力和心率(P<0.05),并被ATP敏感性钾通道阻断剂格列苯脲和钙激活钾通道阻断剂四乙胺部分阻断。②白藜芦醇可降低家兔离体心肌心率,格列苯脲可阻断白藜芦醇的负性变时作用。③电压依赖性钾通道阻断剂4-氨基吡啶、内向整流钾通道阻断剂氯化钡、乙酰胆碱调节钾通道阻断剂阿托品均不能阻断白藜芦醇对3种不同动物离体心房收缩力和心率的作用(P>0.05)。结论:白藜芦醇可呈剂量依赖性减慢豚鼠、小鼠和家兔的心率,白藜芦醇可减弱豚鼠心肌收缩力,其作用是与开放ATP敏感性钾通道有关,而与电压依赖性钾通道、内向整流钾通道和乙酰胆碱调节钾通道无关。同时,钙激活钾通道也参与了白藜芦醇对豚鼠和小鼠离体心房收缩力和/或心率的抑制作用。白藜芦醇对离体心肌收缩力和心率的作用有种属差异性。 相似文献
89.
A randomized, controlled trial of intravenous clodronate in patients with metastatic bone disease and pain 总被引:7,自引:0,他引:7
D. Scott Ernst MD FRCP Penny Brasher PhD Neil Hagen MD FRCP Alexander H.G. Paterson MD FRCP R. Neil MacDonald CM MD FRCP FRCP Eduardo Bruera MD 《Journal of pain and symptom management》1997,13(6):319-326
To evaluate the effectiveness of intravenous clodronate in ameliorating refractory bone pain in patients with metastatic bone disease, 60 patients with established osseous metastases and persistent bone pain were randomized to receive either clodronate (600 mg or 1500 mg in 500 mL of normal saline) or 500 mL of saline as placebo. After 2 weeks, the patients were crossed over to receive the alternate treatment. After another 2 weeks, each patient and investigator made a blinded choice. Daily visual analogue scales (VAS) and analgesic diaries were recorded throughout the study period. Forty-six patients were evaluable (77%). A treatment × period interaction was identified in the VAS and daily morphine equivalent dose (DATED) scores. First period analysis of the VAS scores for general pain, pain at rest, and pain upon movement demonstrated an average reduction of 13, 14, and 24 mm, respectively, from baseline, but were not significantly different from changes following placebo. The average change in DMED was −6 .4 (SE = 2.9) following clodronate and was +24.6 (SE = 14.9) following placebo (p = 0.03). In the blinded choice of which agent resulted in improvement in pain, 26 (57%) patients chose clodronate, 12 (26%) chose placebo, and eight (17%) had no preference (p = 0. 0021). For the investigators who also made a blinded selection, clodronate was chosen in 30 (65%) patients, placebo in ten (22%) patients, and no difference was apparent in six (13%) (p < 0.0001). Intravenous clodronate appeared to have analgesic effect in patients with refractory bone pain due to metastatic bone disease. The optimal dose and duration of effect require further evaluation, particularly in patients with stable disease and persistent bone pain. 相似文献
90.
We studied clinical features potentially related to dysphagia and three
indices from a timed test of swallowing--average volume per swallow (ml),
average time (s) per swallow and swallowing capacity (ml/s)--in 181
screened healthy adults and 30 patients with motor neurone disease (MND).
In healthy adults, age, sex and height accounted for 44.3% and 55.6% of the
variance of log average volume per swallow and log swallowing capacity,
respectively. Symptoms and signs were more prevalent in the MND group and
were associated with reduced swallowing capacity and reduced average volume
per swallow; repeatability studies on these two indices in both groups
showed that the median difference between the mean of two recordings on
successive days and the mean of all recordings (6-15 over 3 days) was <
5% (maximum third quartile 12.8%, indices expressed as percent predicted
according to age and sex). Using this simple bedside test, swallowing
function can be quantified on a ratio scale and expressed as percent of
that predicted by age and sex; such information may improve the predictive
value of clinical assessment and provides a practical way of monitoring
change in patients with dysphagia.
相似文献