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排序方式: 共有2076条查询结果,搜索用时 15 毫秒
31.
J. McCabe C. Guevara J. Renfroe T. Fattahi S. Salman B. Steinberg 《International journal of oral and maxillofacial surgery》2018,47(4):465-469
The aim of this study was to quantitatively evaluate the efficacy of induced hypotensive anesthesia in decreasing facial soft tissue perfusion during orthognathic surgery using laser-assisted indocyanine green fluorescence angiography. This retrospective study involved the evaluation of 16 patients who underwent orthognathic surgery. Data collection included facial tissue perfusion of the bilateral cheeks and chin at normotension and with pharmacologically induced hypotensive anesthesia. There were statistically significant differences in the facial tissue perfusion at normal and depressed levels of blood pressure (P < 0.001). This study used an objective measure to demonstrate the long-standing belief that hypotensive anesthesia is efficacious in reducing tissue perfusion in the surgical field. The data suggest that pharmacologically depressing the level of mean arterial pressure by 18% may result in a 41–52% decrease in facial soft tissue perfusion. This study reports a novel method of quantitative analysis. 相似文献
32.
Yayun Liang Cynthia Besch-Williford Indira Benakanakere Philip E. Thorpe Salman M. Hyder 《Breast cancer research and treatment》2011,125(2):407-420
Breast cancer progression depends upon the elaboration of a vasculature sufficient for the nourishment of the developing tumor.
Breast tumor cells frequently contain a mutant form of p53 (mtp53), a protein which promotes their survival. The aim of this
study was to determine whether combination therapy targeting mtp53 and anionic phospholipids (AP) on tumor blood vessels might
be an effective therapeutic strategy for suppressing advanced breast cancer. We examined the therapeutic effects, singly,
or in combination, of p53 reactivation and induction of massive apoptosis (PRIMA-1), which reactivates mtp53 and induces tumor
cell apoptosis, and 2aG4, a monoclonal antibody that disrupts tumor vasculature by targeting AP on the surface of tumor endothelial
cells and causes antibody-dependent destruction of tumor blood vessels, leading to ischemia and tumor cell death. Xenografts
from two tumor cell lines containing mtp53, BT-474 and HCC-1428, were grown in nude mice to provide models of advanced breast
tumors. After treatment with PRIMA-1 and/or 2aG4, regressing tumors were analyzed for vascular endothelial growth factor (VEGF)
expression, blood vessel loss, and apoptotic markers. Individual drug treatment led to partial suppression of breast cancer
progression. In contrast, combined treatment with PRIMA-1 and 2aG4 was extremely effective in suppressing tumor growth in
both models and completely eradicated approximately 30% of tumors in the BT-474 model. Importantly, no toxic effects were
observed in any treatment group. Mechanistic studies determined that PRIMA-1 reactivated mtp53 and also exposed AP on the
surface of tumor cells as determined by enhanced 2aG4 binding. Combination treatment led to significant induction of tumor
cell apoptosis, loss of VEGF expression, as well as destruction of tumor blood vessels. Furthermore, combination treatment
severely disrupted tumor blood vessel perfusion in both tumor models. The observed in vitro PRIMA-1-induced exposure of tumor
epithelial cell AP might provide a target for 2aG4 and contribute to the increased effectiveness of such combination therapy
in vivo. We conclude that the combined targeting of mtp53 and the tumor vasculature is a novel effective strategy for combating
advanced breast tumors. 相似文献
33.
34.
BACKGROUND: Clinical observations indicate that patients with Alzheimer's disease show a greater susceptibility to infections. One possible explanation is that this predisposition is due to alterations in their immune system. OBJECTIVE: To investigate this assumption, pro- and anti-inflammatory cytokines, as well as the phagocytic activity and superoxide anion generation was examined in aged individuals with and without Alzheimer's disease. METHODS: The production of IL-1beta, IL-2, IL-6, TNFalpha and IL-10 by peripheral blood mononuclear cells from 12 patients with Alzheimer's disease was compared with that of 12 age-matched individuals without any signs of dementia and 12 middle-aged healthy volunteers who served as an additional control. The engulfing capacity of the phagocytic cells was detected by counting cells containing latex beads and the number of particles internalized by each individual cell. RESULTS: The secretion of IL-2 was markedly low in the demented patients, compared with both elderly and middle-aged subjects. IL-1beta and TNFalpha production was similar in the individuals of the 3 groups. The production of IL-6 and IL-10 was significantly lower when compared to that of the middle-aged, but did not differ between the elderly patients with and without dementia. The phagocytic function of both polymorphonuclear cells and monocytes was decreased in individuals of the elderly groups with a low number of engulfed latex particles by each individual polymorphonuclear cell. The production of superoxide anions was increased only by monocytes from the elderly groups. CONCLUSIONS: The results suggest that although the impaired immune function in patients with Alzheimer's disease is related to the aging process, the significant low IL-2 production in these patients may play a role in their increased susceptibility to infections. 相似文献
35.
Stanley Crankson Mohammed J Al Salman Khalid A Al Mane Abdullah A Al Zaben 《Tropical gastroenterology》2004,25(1):47-48
We report the case of a 7-month-old boy who presented with a history of vomiting since birth. A computed tomography study showed circumferential thickening of the lower oesophageal wall with enhancement of the mucosa. After a period of antireflux medication, the patient underwent simultaneous oesophageal dilatation and Nissen fundoplication. He is doing well at 2-year follow up. 相似文献
36.
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38.
Salman Haq M.D. Masi Khaja M.D. Jeffery J. Holt B.S. John Kassotis M.D. Eng. Sci. D. F.A.C.C. 《The International journal of angiology》2006,15(1):16-19
The QT dispersion (QTd) is a non-invasive means of identifying those patients at an increased risk of developing sudden cardiac death (SCD). Although
levofloxacin has a minimal effect on the QTc interval, isolated reports of QT prolongation, polymorphic ventricular tachycardia with a normal QT interval and TdP have
been reported. The purpose of this study was to examine the effect of intravenous levofloxacin on the QT interval and QTd. Of the 50 patients who were deemed candidates to receive intravenous levofloxacin, 29 met the eligibility criteria and were
enrolled in this study. A 12-lead ECG was performed before the initiation of levofloxacin (baseline), and on days 3 and 5.
The QTc
min, QTc
max and the QTd were calculated. Measurements where made by two independent observers blinded to the patients’ clinical status. The QTd increased significantly on days 3 and 5 following the initiation of therapy [QTd (baseline) 33.3 ± 20 ms, QTd (day 3) 64.4 ± 31.3 ms (p = 0.023), QTd (day 5) 66.8 ± 20.3 ms, (p = 0.008)]. The increase in the QTd was significantly longer in men than women. Although women had a shorter baseline QTd compared to men, this did not achieve statistical significance. Intravenous levofloxacin was found to significantly increase
the QTd, which was more pronounced in men compared to women. Its effect on the QTd may increase the risk of developing a potentially fatal ventricular arrhythmia. Therefore, care must be taken when prescribing
this medication to patients with a pre-existing risk of developing SCD. 相似文献
39.
40.
AbstractChronic critical limb ischemia (CLI) occurs when arterial perfusion is reduced below a threshold level that results in rest pain and/or tissue breakdown in the lower extremities. Importantly, it is associated with high cardiovascular morbidity and mortality. Without prompt revascularization, CLI may result in loss of a limb (i.e. amputation) and/or life. The goal of endovascular therapy is the re-establishment of pulsatile, straight-line flow to the distal extremity. Percutaneous transluminal angioplasty (PTA) has been shown to be effective and safe in the setting of CLI, with limb salvage rates that compare favorably with surgical procedures. Stents are indicated for failed PTA, while adjunctive therapies such as lasers, thermal angioplasty and atherectomy devices lack data demonstrating improved efficacy compared with conventional lower extremity interventions. In addition to successful revascularization, the institution of lifestyle changes, atherosclerotic risk factor modification, and pharmacologic therapies are indicated to reduce cardiovascular morbidity and mortality. 相似文献