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81.
N. Z. Klyueva D. B. Ryzhov S. V. Kulikov S. K. Churina 《Bulletin of experimental biology and medicine》1997,124(2):751-753
Injection of a synthetic analog of parathyroid hypertensive factor to WKY rats considerably increases and prolongs pressor
response to adrenaline. Synthetic analog injected after adrenaline induces a short-term (3–4 min) and potent (to 250%) rise
of arterial pressure. Each subsequent injection of the synthetic analog induces a less pronounced in the amplitude and duration
pressor response. The α-adrenoblocker phentolamine completely abolishes the effects of the parathyroid hypertensive factor
analog.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 8, pp. 148–150, August, 1997 相似文献
82.
Summary. Divers have worked at 500 m depth in the sea and have reached 700 m in simulated chamber dives. A prerequisite for this has been extensive physiological studies of the body's reactions to pressure and pressure changes. This paper reviews such physiological and pathophysiological studies with emphasis on recent developments. 相似文献
83.
(胡国栋)(李小明)(黄志程)(胡道予)TheSignificanceofAnatomicalVariationsofHepaticArteryandMultipleArterialSuppliesinEmbolizationofLiverTumors¥HU... 相似文献
84.
Paul F. Jaques Matthew A. Mauro Jeet Sandhu 《Cardiovascular and interventional radiology》1997,20(3):211-212
The hepatic falciform artery is an occasional terminal branch of the left or middle hepatic artery, and may provide an uncommon
but important collateral route when the principal visceral arteries are occluded. 相似文献
85.
S Lalith Talagala Frank Q Ye Patrick J Ledden Scott Chesnick 《Magnetic resonance in medicine》2004,52(1):131-140
A variety of continuous and pulsed arterial spin labeling (ASL) perfusion MRI techniques have been demonstrated in recent years. One of the reasons these methods are still not routinely used is the limited extent of the imaging region. Of the ASL methods proposed to date, continuous ASL (CASL) with a separate labeling coil is particularly attractive for whole-brain studies at high fields. This approach can provide an increased signal-to-noise ratio (SNR) in perfusion images because there are no magnetization transfer (MT) effects, and lessen concerns regarding RF power deposition at high field because it uses a local labeling coil. In this work, we demonstrate CASL whole-brain quantitative perfusion imaging at 3.0 T using a combination of strategies: 3D volume acquisition, background tissue signal suppression, and a separate labeling coil. The results show that this approach can be used to acquire perfusion images in all brain regions with good sensitivity. Further, it is shown that the method can be performed safely on humans without exceeding the current RF power deposition limits. The current method can be extended to higher fields, and further improved by the use of multiple receiver coils and parallel imaging techniques to reduce scan time or provide increased resolution. 相似文献
86.
Quantitative cerebral blood flow (CBF) values can be obtained from dynamic susceptibility contrast (DSC) MR perfusion studies using the standard singular value decomposition (sSVD) deconvolution algorithm. Reports in the literature from simulation and in vivo studies suggest that CBF estimates obtained using sSVD deconvolution depend on the arterial-tissue delay (ATD). By contrast, Fourier transform (FT) deconvolution produces CBF estimates that are independent of ATD. The diagnostic reliability of quantitative CBF measurements to define areas of normal tissue flow and tissue at risk is brought into doubt by such gross sensitivity to the specifics of the deconvolution approach. This variation of CBF values with ATD is shown to be an artifact associated with the current implementation of the sSVD deconvolution algorithm. A reformulated version of the SVD deconvolution algorithm (rSVD) is presented and compared to the standard SVD algorithm through simulation and patient case studies. 相似文献
87.
脊柱转移瘤的双介入治疗 总被引:1,自引:1,他引:0
经皮椎体成形术(PVP)已广泛用于脊柱溶骨性转移瘤的姑息治疗,止痛效果确切,经动脉化疗栓塞(TAE)可以抑制肿瘤生长,缩小肿瘤体积,缓解疼痛。联合应用PVP和TAE(双介入疗法)可增加止痛效果,控制肿瘤生长,增加骨稳定性,提高生活质量。本组收集行PVP4-TAE治疗脊柱转移瘤9例,结合文献初步评价其疗效。 相似文献
88.
腓动脉皮支逆行岛状皮瓣的解剖与应用改进 总被引:6,自引:0,他引:6
目的探讨腓动脉皮支逆行岛状皮瓣的解剖学基础及临床应用效果。方法采用新鲜及防腐尸体下肢共25肢,对腓动脉皮支进行解剖学观测。于2003年9月~2005年6月收治足跖趾关节处软组织缺损患者10例,男8例,女2例。年龄21~55岁。其中背侧6例,跖侧4例,缺损范围10cm×6cm~15cm×10cm。应用带有外踝上11.0±1.7cm腓动脉固定皮支的腓动脉皮支逆行岛状皮瓣修复,皮瓣范围11.0cm×6.5cm~16.0cm×11.0cm。供区6例直接减张缝合,4例行自体游离皮片覆盖。结果解剖学观测外踝上11.0±1.7cm自腓动脉发出一固定皮支,起始点直径1.45±0.12mm,入深筋膜点距腓肠神经营养血管皮瓣轴线15.70±1.20mm。10例患者术后皮瓣均成活,血运良好,无静脉回流障碍;供区愈合良好。术后获随访6~12个月,皮瓣外形良好,质地、色泽与周边相似,足功能恢复良好,两点辨别觉11~18mm。结论腓动脉皮支逆行岛状皮瓣经改进后血运好,逆转距离长,修复范围大,操作简便,为临床修复足中远端软组织缺损提供了一种新方法。 相似文献
89.
Amputation in elderly and high-risk vascular patients 总被引:1,自引:0,他引:1
Fifty-eight patients underwent lower limb amputation for arterial disease over a 30-month period. Mean age of the patients was 72 years. Cardiopulmonary and metabolic risk factors were present in the majority of the patients. Postoperative one-year and three-year mortality rates were 24, 40, and 76%, respectively. Contralateral amputation was required in one-third of the patients after a mean period of eight months. Only younger and healthier patients returned to a meaningful social life after appropriate prosthetic fitting. In view of the high mortality and morbidity rates, above-knee amputation seems a better choice than below-knee amputation in these elderly and high-risk patients. 相似文献
90.
Management of infected prosthetic arterial grafts remains a challenging clinical problem. Revascularization following removal of the infected arterial prosthesis is frequently necessary and usually achieved using remote extraanatomic bypasses. We present three cases where complete removal of the infected prosthesis was followed by autogenous reconstruction using reversed saphenous vein, endarterectomized segments of superficial femoral artery, or endarterectomy of the native occluded vessels. Eradication of the infection was seen in all three patients. The reconstructions have remained patent in the three patients with follow-up from four months to three years. Percutaneous balloon dilation was successful in the management of a distal limb stenosis in one patients. Autogenous vascular reconstruction following removal of infected prosthetic vascular grafts remains a viable alternative in the treatment of difficult, selected cases of infected arterial prosthesis. It is probably an underutilized alternative, when one considers that the surgical techniques employed are familiar to vascular surgeons. Cure of the infection and prepreservation of critical vascular beds can both be achieved with autogenous tissue, either in situ or from remote areas. Available percutaneous techniques may play an important role in maintaining durability of these reconstructions.Presented at the Annual Meeting of the Peripheral Vascular Surgery Society, New York, New York, June 17, 1989. 相似文献