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31.
32.
L. Abrahamsson  H. Hackl 《Maturitas》1981,3(3-4):225-234
53 patients from a mainly climacteric population were treated monthly with 200 mg dehydro-epiandrosterone (DHEA) oenanthate or with 1 ampoule Gynodian-Depot®. Pronounced adiposity was present in 15 of these cases. Hormonal variables were determined before the treatment and during the depot effect of the preparations in order to study the principle which supports the oestrogenic influence and any weight-reducing influence under administration of DHEA. The elimination of lowpolar oestrogens increased considerably in 4 out of 13 post-menopausal cases treated with DHEA. This effect is probably indirect and presupposes intact ovaries. The incorporation of exogenous DHEA into the excretion of 17-ketosteroids and of 17-ketogenic steroids, such as those of androsterone + aethiocholanolone, depends on the size of the initial pool inasmuch as it is higher in small initial pools than in saturated pools - the size of the pool being age-dependent.

An average weight loss of >1 kg/mth was observed under DHEA treatment in 7 out 15 adipose cases. In comparison to the other 8 adipose cases, these 7 were younger and therefore also displayed higher values for 17-ketosteroids and their individual fractions. These circumstances appeared to explain why the administration of DHEA resulted in higher levels of free plasma DHEA which, in contrast to the cases without loss of weight, also resulted in an increase of renal DHEA-sulphate clearance. It was concluded from the findings that this is the explanation for the catabolic effect of exogenous DHEA.

Post-menopausally increased FSH and LH fractions were markedly suppressed in about half of the determinations after Gynodian-Depot administration, the findings indicating that DHEA is probably involved in suppression of the LH fraction.  相似文献   

33.
本文采用体外建立抗原—抗体—补体反应体系的试验方法,通过测定该反应体系的血小板~(51)Cr 释放量来进一步探讨特发性血小板减少紫癜(ITP)患儿血小板的破坏机制。结果45例ITP 惠儿其血小板~(51)Cr 释放量与正常值比较明显增高(P<0.01),急慢性之问无显著差异性。45例患儿中有31例血小板~(51)Cr释放量高出正常值上限。同时观察ITP 患儿血清对血小板超微形态和结构的影响,发现血小板表面有圆钝伪足形成,血小板聚集,血小板脱颗粒和空泡性变。正常儿血清对血小板超微形态和结构无明显影响。作者认为,ITP 患儿的血小板相关抗体,能介导血管内血小板的溶解与破坏,其既影响血小板数量,又改变血小板的结构,二者都是导致该病出血的重要原因。  相似文献   
34.
本文对81例乙型肝炎病人的肝活检组织进行了电镜观察,发现HBsAg的阳性率达93.8%。电镜下,HBsAg细丝不仅有一般的管状细丝型,还有分枝管型和管泡型,而且CAH病人肝组织不易找到HBsAg丝(易见者仅9%),CPH,CLH则多数(79.5%)为易见及可见,二者有高度显著性差异(P<0.01)。  相似文献   
35.
本文用磷酸盐Giemsa法观察了小剂量X射线照射对人离体外周血淋巴细胞SCE的影响。其结果照射组各剂量点均不明显地高于对照组,证实了SCE对电离辐射不敏感,说明染色体结构畸变和SCE的发生是彼此独立的两个不同事件。  相似文献   
36.
目的 探讨电子直线加速器照射对细胞周期及细胞凋亡的影响。方法 采用直线加速器对NIH 3T3细胞进行照射,观察细胞周期及细胞凋亡的改变情况;同时测定损伤前后p53蛋白的表达情况。结果 照射后细胞凋亡数增加,p53蛋白表达量上升。结论 电子直线加速器照射损伤可诱导细胞凋亡。  相似文献   
37.
Steven L. Bressler   《Brain research》1987,409(2):294-301
The major projection pathway of the olfactory bulb is by way of the lateral olfactory tract (LOT) to the olfactory cortex. Oscillatory bursts of extracellular potential appear during inspiration in both bulb and cortex. Based on anatomical and physiological considerations, a model was proposed, consisting of a bulbar transmitter, a conduction line representing axons in the LOT, and a cortical receiver. The model predicted the relation between phase and frequency of bulbar and cortical burst pairs, based on the expectation that the bulb drives the cortex. Experimental phase-frequency plots were computed from bursts of 9 bulbocortical electrode site pairs from each of 10 rabbits. For each site pair, the model predicted the expected range of the joint variation of phase and frequency, using the known distance between the bulbar and cortical sites. The model was highly successful (greater than 95% prediction accuracy) for one quarter of the total number of site pairs examined. The wide range of variation for the rest of the data suggested that higher order interactions are responsible for the phase relation between bulb and cortex. Convergence of input, independence of the cortical generator, cortical feedback to the bulb and synchronization by an outside source are all discussed as possible contributors to this variation.  相似文献   
38.
荷包环扎式结直肠吻合保肛术治疗低位直肠癌*   总被引:1,自引:1,他引:0  
目的 :评价荷包环扎式结直肠吻合保肛术治疗低位直肠癌的价值。方法 :对低位直肠癌采用荷包环扎结直肠吻合保肛术治疗 2 3例 (A组 ) ,采用Miles手术治疗 2 6例 (B组 )。结果 :A组术后 1、3年生存率分别为 10 0 % (2 3/ 2 3) ,95 7% (2 2 / 2 3) ,术后无局部复发病例 ;排便功能优 16例 (6 9 6 % ) ,良 7例 (30 4 % )。B组术后 1、3年生存率分别为 10 0 % (2 6 / 2 6 ) ,96 2 % (2 5 /2 6 ) ,术后局部复发率 3 8% (1/ 2 6 )。两组术后 1、3年生存率 ,局部复发率经统计检验 ,均无显著差异 (P值均 >0 0 5 )。术后并发症 :A组无吻合口瘘及吻合口狭窄发生 ,盆腔感染 1例。B组 :切口感染 1例 ,人工肛门狭窄 1例。结论 :采用螺纹支架管荷包环扎结直肠吻合保肛术治疗低位直肠癌既能达到根治目的 ,又有保留肛门的良好排便功能 ,且并发症少 ,操作简便易行 ,不用特殊器械 ,值得推广应用  相似文献   
39.
Background  Surgical procedures enhance production of pro- and anti-inflammatory cytokines and angiogenic factors that play a pivotal role in the immunological response to surgical trauma and take part in the pathogenesis of tumor growth and adhesions formation. The purpose of the study was to access the influence of low-pressure CO2 pneumoperitoneum on the inflammatory and angiogenic responses during the postoperative period after laparoscopy. Methods  The study group consisted of 40 patients, operated on due to cholelithiasis using standard-pressure (n = 20) and low-pressure (n = 20) CO2 pneumoperitoneum. Serum concentration of interleukin (IL)-6, IL-8, IL-10, vascular endothelial growth factor (VEGF)-A, and endostatin were measured before and at 6, 24, and 48 h after surgery with commercially available enzyme-linked immunosorbent assay (ELISA). Results  Concentrations of IL-6 increased significantly after the operations in both groups. No differences were observed between the groups in regards to IL-6, IL-8, and IL-10 levels. Concentrations of VEGF-A measured at 6 and 48 h were significantly lower in patients who underwent laparoscopies performed with low-pressure pneumoperitoneum. No significant variations were observed in endostatin serum concentration. Concentrations of the studied parameters were not influenced by duration of surgery or by age, gender, or body mass index (BMI) of the patients. Conclusions  The results obtained in our study do not show any significant differences between studied operative procedures with regards to systemic inflammatory response. Changes in the concentrations of VEGF-A and endostatin observed in the studied population may suggest this technique is more favorable with regards to angiogenesis process intensity, along with all its consequences and implications.  相似文献   
40.
The human prostatic urethra has been investigated by means of scanning electron microscopy. On the posterior wall of the urethra, the seminal colliculus with the orifices of the ejaculatory ducts is clearly detectable. The upper portion of the prostatic urethra shows a typical transitional epithelium with large superficial cells of a ruffled appearance. In the lower portion of the organ (underneath the openings of the ejaculatory ducts), the apical pattern of the cells varies considerably. Four main aspects are recognizable: apices provided with microvilli, dome-shaped apices with an almost smooth surface, large apices with labyrinthic microplicae and ciliated apices. Also, apices showing intermediate characteristics can be noted. The functional significance of the morphological patterns as well as the possibility of a transition among the various types of surface structures are discussed.  相似文献   
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