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1.
2.
对地方性氟病病区胎儿肾上腺皮质细胞进行超微结构体视学研究。结果显示:病区胎儿肾上腺皮质细胞核比表面和核平均体积缩小,细胞平均截面积和平均体积缩小;线粒体肿胀,平均周长和平均体积增大;粗面内质网体密度缩小。结果表明:机体过量氟对胎儿肾上腺皮质细胞超微结构有损伤作用。  相似文献   
3.
This article reviews the anatomical and functional evidence for ascending pathways from specific brain regions to the PVN and SON which could influence AVP release. The majority of evidence favours the main projection being from a region in the caudal VLM which may coincide with the noradrenergic neurons of the A1 cell group. However, the transmitter(s) involved have yet to be identified, and whether the pathway is excitatory and/or inhibitory remains to be fully resolved.Anatomical and functional evidence is reviewed for descending projections from the SON and PVN to specific brain regions involved in cardiovascular control, and their possible involvement in baroreflex mechanisms is discussed. However, there is little unequivocal evidence that AVP is the main neurotransmitter utilized by descending projections from PVN to NTS and DMX. While, in some situations, circulating endogenous AVP exerts cardiovascular effects, details of its putative influences on baroreflex mechanisms are lacking.  相似文献   
4.
CT导向下经皮射频消融术治疗肾上腺恶性肿瘤   总被引:4,自引:0,他引:4  
目的对29例肾上腺肿瘤患者行射频消融(RFA)治疗,研究其近期局部治疗效果、不良反应和副作用。方法肾上腺肿瘤患者共29例,病灶总数31个,其中直径≤2.0cm的病灶共5个,2.1-4.0cm者18个,4.1-6.0cm者5个,≥6.1cm者3个,经RFA治疗1个月后行螺旋CT双期增强扫描评价肿瘤治疗效果。结果上述病灶经消融治疗后达到完全坏死者分别为5个、18个、3个、2个。患者无严重并发症出现。结论RFA治疗安全可靠,副作用小,是治疗肾上腺恶性肿瘤的有效方法之一。  相似文献   
5.
Objective To investigate a novel method of adrenocotical cells transplantation. Methods Adrenal glands of neonate rats were dissociated into adrenal cortical cells. Cells were cultured in self-made collagen type Ⅰ gel for one week, and then transplanted under the renal capsule of bilateral adrenalectomy mate rats. Blood samples were collected per week after surgery. Animals were sacrificed at the 8th week, and histological characteristics of the allografts, proliferation of transplanted cells, CYP11B1 and CYP11B2 expression as well as plasma aldosterone and corticosterone were observed. Results There were totally 15 rats receiving collagen gel transplantation, and 12 survived 8 weeks post-operation. The plasma cortocosterone level in collagen gel transplantation group was significantly higher than in adrenocortical cell transplantation group, and reached the normal level from 6th to 8th week, but the change in plasma aldosterone level in collagen gel transplantation group was similar to that of adrenocortical cell transplantation group. The adrenocortical cells cultured in gel grew well, and had a high proliferation rate. 95% of them were fasciculata cells which expressed CYP11B1, and the rest were glomerulosa cells which expressed CYP11B2. No inflammatory cell infiltration was observed. Conclusion The proliferation and function of adrenocortical cells could be promoted when they were cultured in collagen gel.  相似文献   
6.
后腹腔镜治疗肾上腺肿瘤35例临床分析   总被引:15,自引:9,他引:6  
目的总结后腹腔镜技术治疗肾上腺肿瘤的临床经验.方法采用后腹腔镜切除肾上腺肿瘤35例,男12例,女23例.年龄25岁~72岁,平均49.8岁.左侧15例,右侧20例.其中嗜铬细胞瘤5例,原发性醛固酮增多症10,柯兴氏病2例,神经节细胞瘤2例,无功能性腺瘤16例.腰部取3个套管针穿刺入路,用自制的水囊扩张器扩张后腹腔,用超声刀将肿瘤切除.结果 35例手术均成功,无中转开放手术病例.术中出血量10~500 ml,平均74 ml.病人均未输血.手术时间45~200 min,平均90 min.结论后腹腔镜手术切除肾上腺肿瘤手术效果确切,手术时间短,术中出血少,损伤小,术后恢复快,可以替代绝大多数肾上腺肿瘤开放手术.  相似文献   
7.
The distribution of methionine-enkephalin-Arg6-Gly7-Leu8, a unique peptide derived from proenkephalin A in the rat brainstem, was studied immunocytochemically by using a highly specific antiserum to this octapeptide sequence. Immunoreactive perikarya with various shapes and sizes were detected in many regions of the rat brainstem. Dense accumulation of immunoreactive perikarya and fibers was seen in the nuclei associated with special sensory and visceral functions, such as the interpeduncular nucleus, the parabrachial nucleus, the nucleus of the solitary tract, and the nucleus of the spinal tract of the trigeminal nerve. Clusters of methionine-enkephalin-Arg6-Gly7-Leu8-like immunoreactive perikarya and fibers were observed in certain areas considered to play a role in nociception and analgesia, such as the central gray of the midbrain central gray and the raphe magnus nucleus. Some methionine-enkephalin-Arg6-Gly7-Leu8-like immunoreactive perikarya were distributed in the lateral reticular nucleus, the nucleus of the solitary tract, and the raphe magnus nucleus, where monoaminergic neurons were also detected. In addition to the previously reported enkephalinergic cells, we found many methionine-enkephalin-Arg6-Gly7-Leu8 containing neurons; the rostral and caudal linear nucleus of raphe, the median raphe nucleus, entire length of the raphe magnus nucleus, the medial longitudinal fasciculus, the cuneate nucleus, the external cuneate nucleus, the gracile nucleus, and the area postrema. The wide distribution of this octapeptide-like immunoreactivity reflected neurons expressing the preproenkephalin A gene distributed more widely than previously reported and that innervated many regions.  相似文献   
8.
王曙  郭旭明 《上海医学》1997,20(7):377-379
应用一次法口服4mg/kg的米非司酮(RU486)观察17例单纯性肥胖和7例疑似库欣组的病人服药前后的反应,并与10例正常人以及29例库欣综合征病人进行比较,发现库欣综合征病人服药以后,血F24小时尿F及血ACTH均无显著性变化(P〉0.05),而其他三组各指标均升高(P〈0.01)。并得出鉴别库欣综合征与非库欣综合征的标准为:血F增加的百分比为30%24小时尿F增加百分比为18%,ACTH增加百  相似文献   
9.
急性中风中脏腑证型与垂体-肾上腺轴激素关系的研究   总被引:6,自引:0,他引:6  
目的 :探讨急性中风中脏腑证型与垂体—肾上腺轴激素的促肾上腺皮质激素 (ACTH)、皮质醇 (CS)的关系。方法 :对 78例中脏腑患者进行辨证分型 ,同时利用放射免疫分析 (RIA)法测定血中 ACTH、CS含量 ,按证型分为四组 ,对比不同证型间 ACTH、CS的水平 ,并与健康人组 (60例 )作对照。结果 :ACTH、CS含量水平比较 :1四种证型的 ACTH、CS均比正常健康人组高 (P <0 .0 0 1 ) ;2四种证型间比较有明显差异 (P<0 .0 1 ) ,从高到低为 :痰热内闭心窍证 >风火上扰清窍证 >痰湿蒙塞心神证 >元气败脱、心神散乱证。结论 :ACTH、CS含量水平可作为判别中脏腑不同证型间的微观指标  相似文献   
10.
1. Nitric oxide (NO) has been implicated as an important controller in the short- and long-term regulation of arterial pressure. Studies performed in our laboratory have demonstrated that chronic intravenous administration of the NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) selectively decreases renal medullary blood flow, causes sodium and water retention and leads to hypertension. 2. To determine the importance of the renal medullary effects in this model of hypertension, further studies were conducted to examine the influence of selective stimulation or inhibition of renal medullary NO on whole kidney function and cardiovascular homeostasis. With the use of a unique catheter to directly infuse into the renal medullary interstitial space, stimulation (bradykinin or acetylcholine) or inhibition (L-NAME) of renal medullary NO selectively increased or decreased renal medullary blood flow. 3. The changes in medullary flow in these experiments were associated with parallel changes in sodium and water excretion independent of alterations in renal cortical blood flow or glomerular filtration rate. 4. Studies were then undertaken to examine the long-term effects of selective NO inhibition in the renal medulla on cardiovascular homeostasis. Chronic infusion of L-NAME directly into the renal medullary interstitial space of uninephrectomized Sprague-Dawley rats led to a selective decrease in renal medullary blood flow that was sustained throughout the 5 day L-NAME infusion period. The decrease in medullary blood flow was associated with retention of sodium and the development of hypertension and the effects were reversible. 5. The data reviewed indicate that NO in the renal medulla has a powerful influence on fluid and electrolyte homeostasis and the control of blood pressure.  相似文献   
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