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41.
Color Doppler ultrasound (US) with point-spectral analysis was performed on eight patients with postbiopsy renal transplant arteriovenous fistulas. Waveform analysis of the supplying artery documented decreased resistive indices in all cases and increased flow velocities in seven. The peak-systolic flow velocity in the arteries supplying the fistulas ranged from 55 to 180 cm/sec (mean, 92 cm/sec), while the range in normal arteries was 20-52 cm/sec (mean, 32 cm/sec). The resistive indices of the arteries supplying the fistulas ranged from 0.31 to 0.50 (mean, 0.45), while the resistive indices of the normal arteries ranged from 0.60 to 0.92 (mean, 0.74). Arterialization of the venous waveform from the draining vein was also documented in all cases. In six cases, the increased flow velocities resulted in increased color saturation toward white in the supplying artery (n = 2) or in both the artery and the draining vein (n = 4), which was detectable on the realtime image. In six cases, flow turbulence resulted in localized tissue vibration, which appeared as random color assignment in extravascular renal parenchyma adjacent to the fistula. Knowledge of these imaging and Doppler characteristics should aid in the identification of renal transplant arteriovenous fistulas with color Doppler US.  相似文献   
42.
43.
Guit  GL; Shaw  PC; Ehrlich  J; Kroon  HM; Oudkerk  M 《Radiology》1985,154(2):305-306
A case of mixed connective tissue disease (MCTD) is presented in which mediastinal lymphadenopathy was the most prominent radiological finding detected by plain chest radiographs and computed tomography. Pulmonary arterial hypertension, which is a rare and often fatal complication of MCTD, also developed in this patient.  相似文献   
44.
香菇多糖的免疫调节作用   总被引:26,自引:0,他引:26  
研究香菇多糖(LTN)的免疫调节作用。结果表明,LTN1及5mg·kg-1·d-1×6,ip可促进正常小鼠由ConA(2.5mg·kg-1)刺激的脾脏T淋巴细胞增殖反应。1,5及10mg·kg-1·d-1×8或5,ip能分别纠正由环磷酰胺(Cy,200mg·kg-1和80mg·kg-1,ip)诱导的免疫亢进或低下状态。此外,LTN(1,5和10mg·kg-1·d-1×6,ip),促使小鼠胸腺L3T4+(Th)和Lyt2+(Ts)细胞数减少,外周脾脏L3T4+和Lyt2+细胞数增加,腹腔巨噬细胞释出肿瘤坏死因子(TNF)也明显增加。这些作用均以LTN5mg·kg-1·d-1作用最佳。提示LTN可能通过影响T细胞及其亚型,促进TNF活性调节机体的免疫功能。  相似文献   
45.
1. The subfornical organ, median preoptic nucleus and the organum vasculosum of the lamina terminalis (OVLT) are a series of structures situated in the anterior wall of the third ventricle and form the lamina terminalis. The OVLT and ventral part of the median preoptic nucleus are part of a region known as the anteroventral third ventricle region.
2. Data from many laboratories, using techniques ranging from lesions, electrophysiology, neuropharmacology, Fos expression, immunohistochemistry and receptor localization, indicate that the tissue in the lamina terminalis plays a major role in many aspects of body fluid and electrolyte balance.
3. The subfornical organ and OVLT lack the blood-brain barrier and detect alterations in plasma tonicity and the concentrations of circulating hormones such as angiotensin II and possibly atrial natriuretic peptide and relaxin.
4. This information is then integrated within the lamina terminalis (probably in the median preoptic nucleus) with neural signals from other brain regions. The neural output from the lamina terminalis is distributed to a number of effector sites including the paraventricular (both parvo- and magno-cellular parts) and supraoptic nuclei and influences vasopressin secretion, water drinking, salt intake, renin secretion, renal sodium excretion and cardiovascular regulation.  相似文献   
46.
用Harris冠脉结扎法诱发的心律失常狗研究常咯啉药代动力学-药效动力学。7只狗按83.33μg·kg-1·min-1静脉滴注60min,在给药期间和停药后不同时间记录ECG及测定血药浓度。C-T数据用药代程序计算药代参数;药效数据用药代-药效同步分析模型计算药效动力学参数,K10, T1/2,Vd,Cl分别为0.0087min-1,78.03min,40.55ml·kg-1和0.421ml·kg-1·min-1;KeOCe(50)分别为0.0048min-1和2.01μg·ml-1.  相似文献   
47.
  • 1 Autoradiographic binding studies have shown that the AT1 receptor is the predominant angiotensin II (AngII) receptor subtype in the central nervous system (CNS). Major sites of AT1 receptors are the lamina terminalis, hypothalamic paraventricular nucleus, the lateral parabrachial nucleus, rostral and caudal ventrolateral medulla, nucleus of the solitary tract and the intermediolateral cell column of the thoraco-lumbar spinal cord.
  • 2 While there are differences between species, AT2 receptors are found mainly in the cerebellum, inferior olive and locus coeruleus of the rat.
  • 3 Circulating AngII acts on AT1 receptors in the subfornical organ and organum vasculosum of the lamina terminalis (OVLT) to stimulate neurons that may have a role in initiating water drinking.
  • 4 Centrally administered AngII may act on AT1 receptors in the median preoptic nucleus and elsewhere to induce drinking, sodium appetite, a sympathetic vasoconstrictor response and vasopressin secretion.
  • 5 Recent evidence shows that centrally administered AT1 antagonists inhibit dipsogenic, natriuretic, pressor and vasopressin secretory responses to intracerebroventricular infusion of hypertonic saline. This suggests that an angiotensinergic neural pathway has a role in osmoregulatory responses.
  • 6 Central angiotensinergic pathways which include neural inputs to the rostral ventrolateral medulla may use AT1 receptors and play a role in the function of sympathetic pathways maintaining arterial pressure.
  相似文献   
48.
用Harris冠脉结扎法诱发的心律失常狗研究常咯啉药代动力学-药效动力学。7只狗按83.33μg·kg ̄(-1)·min ̄(-1)静脉滴注60min,在给药期间和停药后不同时间记录ECG及测定血药浓度。C-T数据用药代程序计算药代参数;药效数据用药代-药效同步分析模型计算药效动力学参数,K10,T1/2,Vd,Cl分别为0.0087min ̄(-1),78.03min,40.55ml·kg ̄(-1)和0.421ml·kg ̄(-1)·min ̄(-1);Ke0和Ce(50)分别为0.0048min ̄(-1)和2.01μg·ml ̄(-1).  相似文献   
49.
    
BACKGROUND: Splenectomy and pericardial devasculariza-tion (SPD) is an effective treatment of upper gastrointestinal bleeding and hypersplenism in cirrhotic patients with portal hypertension. Indocyanine green retention at 15 minutes (ICGR15) was reported to offer better sensitivity and speciifc-ity than the Child-Pugh classiifcation in hepatectomy, but few reports describe ICGR15 in SPD. The present study was to evaluate the prognostic value of ICGR15 for cirrhotic patients with portal hypertension who underwent SPD.
METHODS: From January 2012 to January 2015, 43 patients with portal hypertension and hypersplenism caused by liver cirrhosis were admitted in our center and received SPD. The ICGR15, Child-Pugh classiifcation, model for end-stage liver disease (MELD) score, and perioperative characteristics were analyzed retrospectively.
RESULTS: Preoperative liver function assessment revealed that 34 patients were Child-Pugh class A with ICGR15 of 13.6%-43.0% and MELD score of 7-20; 8 patients were class B with ICGR15 of 22.8%-40.7% and MELD score of 7-17; 1 patient was class C with ICGR15 of 39.7% and MELD score of 22. The optimal ICGR15 threshold for liver function com-pensation was 31.2%, which offered a sensitivity of 68.4% and a speciifcity of 70.8%. Univariate analysis showed preopera-tive ICGR15, MELD score, surgical procedure, intraoperative blood loss, and autologous blood transfusion were signiifcant-ly different between postoperative liver function compensated and decompensated groups. Multivariate regression analysis revealed that ICGR15 was an independent risk factor of post-operative liver function recovery (P=0.020).
CONCLUSIONS: ICGR15 has outperformed the Child-Pugh classiifcation for assessing liver function in cirrhotic patients with portal hypertension. ICGR15 may be a suitable prognos-tic indicator for cirrhotic patients after SPD.  相似文献   
50.
Adrenal glands in patients with congenital renal anomalies: CT appearance   总被引:1,自引:0,他引:1  
Kenney  PJ; Robbins  GL; Ellis  DA; Spirt  BA 《Radiology》1985,155(1):181-182
The CT appearance of the adrenal glands was investigated in 30 patients with congenital renal anomalies (17 cases of unilateral renal agenesis, 11 of inferior ectopy, and 2 of crossed fused ectopy). The ipsilateral adrenal was clearly identified in 83% of these patients; in all of them, the adrenal was a paraspinal disk-shaped organ, which appeared linear on CT. Conversely, the adrenals retained their normal shape in a control group of 20 patients with acquired renal atrophy or prior simple nephrectomy.  相似文献   
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