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91.
目的:研究一种新的导管法测定肺循环血流量。方法:分离右侧颈外静脉,将塑料导管自右侧颈外静脉插入,经上腔静脉、右心房和右心室插入肺动脉。用上海产SJ—42型四导生理记录仪记录生理参数。结果:肺循环血流量可按公式QP=MPAP·△QMPAP-MPAP计算,式中△Q是每分钟自肺循环流入容量测定计的血量,算得的QP=29.62±3.73ml/min,在大鼠的肺循环血流量正常范围之内。结论:该方法精确而且操作简便  相似文献   
92.
AIM: To determine current clinical practice in the radiological diagnosis of acute pulmonary embolism and assess the use of spiral volumetric computed tomography. METHOD: A survey of 327 acute hospitals including cardiothoracic and orthopaedic tertiary referral centres was undertaken to assess current utilization of lung scintigraphy, spiral computed tomography and pulmonary angiography in the investigation of suspected pulmonary embolism. Responses were received from 215/327 (66%) centres. RESULTS: Lung scintigraphy was provided by 208 hospitals (144 on-site and 64 off-site). Spiral CT services were provided by 111 (52%) hospitals (on- or off-site), 142 (66%) units had access to angiographic facilities. Sixty-three centres out of 215 (29%) offered both on-site lung scintigraphy and spiral CT while only 41/215 (19%) hospitals were able to undertake all three tests on-site. On average, 501 perfusion (Q) or ventilation-perfusion (V/Q) scintigrams were performed per hospital per year with 26 spiral CT studies and just 4.6 pulmonary angiograms. CONCLUSION: These data suggest that lung scintigraphy is frequently the only imaging test in patients other than chest radiography, despite the large number of indeterminate results reported in most series.  相似文献   
93.
Respiratory diseases are a major cause of morbidity and mortality in developing countries. Recurrent respiratory infections in children pose a great challenge to the pediatrician where he has to exercise his clinical acumen and methodical, approach, for correct diagnosis and treatment. It is a fact that children should suffer 7 to 8 upper respiratory infections per year until they are 5 years of age when their immune status reaches adult level. In this situation, it is essential to find out whether the frequencies are abnormal. Whenever a child has the following, problems, then only it needs to be investigated.—(a) repeated bacterial pneumonias; (b) a child less than 3 months old having repeated respiratory infections; (c) a child of 9 months old without a history of exposure infections; (d) infections, complicating into bronchiectasis and; (e) in a child where there is no history of allergy or asthma. Once the problem is established as a true recurrent respiratory infection, the clinician should pose questions—whether it is chronic, acute or recurrent, to find out the site of pathology, seriousness of the problem, response to previous medications, to establish the possible diagnosis which fall into six categories—congenital anamolies, aspiration syndrome, genital disorders, immunological, diseases, immune deficiency disorders and allergic diseases. The author discusses quoting some examples for various categories avoiding non pulmonary causes for recurrent respiratory infections in children.  相似文献   
94.
A method for quantifying mitral and tricuspid regurgitant volume that utilizes a measure of jet orifice velocity U(0) - m/sec), a distal centerline velocity (U(m) - m/sec), and the intervening distance (X - cm) was recently developed; where jet flow rate (Q(cal) - L/min) is calculated as Q(cal) = (U(m)X)(2)/(26.46U(o)). This method, however, modeled the regurgitant jet as a free jet, whereas many atrial jets are counterflowing jets because of jet opposing intra-atrial flow fields (counterflows). This study concentrated on the feasibility of using the free jet quantification equation in the atrium where ambient flow fields may alter jet centerline velocities and reduce the accuracy of jet flow rate calculations. A 4-cm wide chamber was used to pump counterflows of 0, 4, and 22 cm/sec against jets of 2.3, 4.8, and 6.4 m/sec originating from a 2-mm diameter orifice. For each counterflow-jet combination, jet centerline velocities were measured using laser Doppler anemometry. For free jets (no counterflow), flow rate was calculated with 98% mean accuracy. For all jets in counterflow, the calculation was less accurate as: (i) the ratio of jet orifice velocity to counterflow velocity decreased (U(o)/U(c), where U(c) is counterflow velocity), i.e., the counterflow was relatively more intense, and (ii) centerline measurements were made further from the orifice. But although counterflow lowered jet centerline velocities beneath free jet values, it did so only significantly in the jet's distal portion (X/D > 16, i.e., >16 orifice diameters from the origin of the jet). Thus, the initial portion (X/D < 16) of a jet in counterflow behaved essentially as a free jet. As a result, even in significant counterflow, jet flow rate was calculated with >93% accuracy and >85% for jets typical of mitral and tricuspid regurgitation, respectively. Counterflow lowers jet centerline velocities beneath equivalent free jet values. This effect, however, is most significant in the distal portion of the jet. Therefore, regurgitant jets, although not classically free because of systolic atrial inflow or jet-induced intra-atrial swirling flows, will decay in their initial portions as free jets and thus are candidates for quantification with the centerline technique. (ECHOCARDIOGRAPHY, Volume 13, July 1996)  相似文献   
95.
我院1985年1月至1989年10月收治的378例次肺心病急发期合并多脏器功能损害(Msof)156例41.2%,死亡53例(34.0%)。其中单脏器损害最多是肺脑91例(58.3%),病死率最高是DIC,5例均死亡,其次是上消化道出血死亡21例(72.4%)、循环衰竭死亡11例(57.8%)。本文提示:肺部感染、严重低氧血症、CO_2潴留为发病基础,同时,对并发MSOF的发病机理,影响预后的因素进行了讨论,井提出了降低病死率的几个关键性问题。  相似文献   
96.
Systemic and pulmonary venous anomalies are frequently encountered either as isolated lesions or as a significant component of a more complex lesion in the newborn infant with congenital heart disease. Two-dimensional echocardiography and Doppler techniques (conventional and color flow) have become the primary diagnostic imaging modality in this setting. Precise pre-operative definition of these variable venous connection and drainage patterns is critical as the required surgical procedure may solely be based on exact understanding of the veins' anatomy and physiology. On the systemic venous site, anomalies of superior and inferior venae cavae, innominate vein, and coronary sinus can be equally well imaged with either echocardiography or angiography. However, on the pulmonary venous site, echocardiography and Doppler techniques including color flow mapping are superior to angiography for precise definition of the connection and drainage sites of the individual pulmonary veins.  相似文献   
97.
Administration of the nephrotoxic agent, bichloride of mercury (HgCl2), to BALB/c mice bearing subcapsular renal tumor transplants induced early preferential necrosis of the tumor cells compared with mercury-treated normal kidney tubular cells and untreated control tumors. The principle is established that a selective proximal tubular poison is also toxic for a tumor of the same cellular origin.  相似文献   
98.
超声心动图对儿童完全性肺静脉异位引流诊断价值的探讨   总被引:2,自引:0,他引:2  
目的 旨在评价超声心动图对完全性肺静脉异位引流 (TAPVD)的诊断价值。方法 对 1987年 9月至2 0 0 2年 11月收治的TAPVD患儿 70例进行分析。均有完整的临床及超声心动图资料 ,其中 35例施行了手术治疗。结果  70例TAPVD的解剖分型为 :心内型 5 2例、心上型 16例、心下型 2例 ,未发现混合型。 35例施行手术 ,32例与术前超声心动图的诊断一致 ;3例与超声心动图诊断不完全一致 ,其超声心动图诊断分别为 :三房心伴继发孔房缺、左房隔膜伴继发孔房缺、原发孔房缺伴卵圆孔未闭 ,而手术结果均显示为心内型TAPVD伴继发孔房缺。结论 超声心动图检查是诊断TAPVD重要且准确的方法 ,并能确定其分型 ,提供精确的解剖及血流动力学资料。在应用超声心动图诊断TAPVD时 ,应注意与三房心、左房隔膜等疾病进行鉴别。  相似文献   
99.
目的 探讨Ⅰb—Ⅱb期手术治疗的宫颈腺癌卵巢转移的高危因素 ,并分析预后因素。方法 回顾性研究 32例Ⅰb—Ⅱb期手术治疗的宫颈腺癌的临床病理特点 ,应用 χ2 检验及logistic回归分析探讨 4例卵巢转移的高危因素 ;应用Kaplan -Meier法及Cox回归模型分析预后因素。结果 单因素分析提示卵巢转移的高危因素是临床分期和盆腔淋巴结转移 ,但多因素分析没有发现有统计学意义的危险因素。Cox回归提示肿瘤大小和盆腔淋巴结转移是独立预后因素。结论 对于有高危因素的宫颈腺癌 ,术中保留卵巢需要慎重。  相似文献   
100.
AIM: To evaluate the anti-inflammatory effect of methoxyphenamine compound (MC) on chronic obstructive pulmonary disease (COPD) in rats by measurement of proinflammatory cytokines, total and differential white cell counts (WCC) of bronchroalveolar lavage fluid (BALF). METHODS: Adult rat model of COPD (COPD group) was induced by intratracheal instillation of lipopolysaccharides and exposure to cigarette smoke. Treatment groups received different dosage of MC (3, 9, and 27 mg daily, MC group) or prednisone (0.25 mg daily, P group) respectively. Tumor necrosis factor alpha (TNF-α), interleukin 1beta (IL-113), interleukin-6 (IL-6), transforming growth factor β (TGF-β) of BALF were determined by ELISA. Total and differential WCC were performed after Giemsa staining. RESULTS: The levels of TNF-α, IL-1β, IL-6, TGF-β, total and differential WCC in BALF of MC groups were significantly decreased than that of COPD group (P<0.01), and there was no significant difference among MC groups. There was no significa  相似文献   
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