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71.
M. A. Karalexi N. Dessypris A. Skalkidou S. -I Biniaris-Georgallis Ε. Ι. Kalogirou T. P. Thomopoulos E. Herlenius L. G. Spector D. Loutradis G. P. Chrousos E. Th. Petridou 《Cancer causes & control : CCC》2017,28(6):599-624
Purpose
History of fetal loss including miscarriage and stillbirth has been inconsistently associated with childhood (0–14 years) leukemia in subsequent offspring. A quantitative synthesis of the inconclusive literature by leukemia subtype was therefore conducted.Methods
Eligible studies (N?=?32) were identified through the screening of over 3500 publications. Random-effects meta-analyses were conducted on the association of miscarriage/stillbirth history with overall (AL; 18,868 cases/35,685 controls), acute lymphoblastic (ALL; 16,150 cases/38,655 controls), and myeloid (AML; 3042 cases/32,997 controls) leukemia. Sensitivity and subgroup analyses by age and ALL subtype, as well as meta-regression were undertaken.Results
Fetal loss history was associated with increased AL risk [Odds Ratio (OR) 1.10, 95% Confidence Intervals (CI) 1.04–1.18]. The positive association was seen for ALL (OR 1.12, 95%CI 1.05–1.19) and for AML (OR 1.13, 95%CI 0.91–1.41); for the latter the OR increased in sensitivity analyses. Notably, stillbirth history was significantly linked to ALL risk (OR 1.33, 95%CI 1.02–1.74), but not AML. By contrast, the association of ALL and AML with previous miscarriage reached marginal significance. The association of miscarriage history was strongest in infant ALL (OR 2.34, 95%CI 1.19–4.60).Conclusions
In this meta-analysis involving >50,000 children, we found noteworthy associations by indices of fetal loss, age at diagnosis, and leukemia type; namely, of stillbirth with ALL and miscarriage history with infant ALL. Elucidation of plausible underlying mechanisms may provide insight into leukemia pathogenesis and indicate monitoring interventions prior to and during pregnancy.72.
W D Travis R I Linnoila M G Tsokos C L Hitchcock G B Cutler L Nieman G Chrousos H Pass J Doppman 《The American journal of surgical pathology》1991,15(6):529-553
Based on our review of 35 cases and the literature, we found the spectrum of pulmonary neuroendocrine (NE) tumors to be too broad to fit into the traditional three-category classification scheme of typical carcinoid (TC), atypical carcinoid (AC), and small-cell lung carcinoma (SCLC). We found that a spectrum of high- and low-grade tumors exist between TC and SCLC and that in the past many of these tumors have been called AC. We chose to adhere to Arrigoni's definition of AC, as his original criteria characterized a low-grade tumor. For the higher grade non-small-cell tumors (NSCLC), we propose a fourth category of large-cell neuroendocrine carcinoma (LCNEC), which is characterized by: (a) light microscopic NE appearance; (b) cells of large size, polygonal shape, low nuclear-cytoplasmic ratio (N:C), coarse nuclear chromatin, and frequent nucleoli; (c) high mitotic rate [greater than 10/10 high-power fields (HPF)] and frequent necrosis; and (d) NE features by immunohistochemistry (IHC) or electron microscopy (EM). Thus, after deciding that a pulmonary NE tumor is high grade, the major diagnostic issue is separation of LCNEC from SCLC. This distinction is based not only on cell size, but on a variety of morphologic features. We studied 20 TC, six AC, five LCNEC, and four SCLC and characterized the clinical, light microscopic, EM, IHC, and flow cytometric features of each type of tumor. We did not find any advantage to IHC, EM, or flow cytometry over light microscopy in the subclassification or prediction of prognosis; however, these methods were useful in characterizing these four types of pulmonary NE tumors and in demonstrating their NE properties. LCNEC must be distinguished from a fifth category pulmonary NE tumor: NSCLC with NE features in which NE differentiation is not evident by light microscopy and must be demonstrated by EM or IHC. Although the prognosis of LCNEC appears to be intermediate between AC and SCLC, larger numbers of patients will be needed to demonstrate significant differences in survival. 相似文献
73.
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Suppression of hypothalamic-pituitary-adrenal axis responsiveness to stress in a rat model of acute cholestasis. 下载免费PDF全文
M G Swain V Patchev J Vergalla G Chrousos E A Jones 《The Journal of clinical investigation》1993,91(5):1903-1908
Cholestatic patients undergoing surgery have increased mortality and demonstrate clinical features suggestive of adrenal insufficiency. To examine whether cholestasis influences the status of the hypothalamic-pituitary-adrenal axis, we evaluated rats with acute cholestasis caused by bile duct resection (BDR) and sham-operated and unoperated controls. Basal unstressed plasma concentrations of ACTH and corticosterone were similar in BDR and sham-operated and unoperated control rats. However, exposure of BDR rats to saturated ether vapor resulted in significantly less ACTH and corticosterone release in plasma than in the control animals. To understand the mechanism(s) of decreased HPA axis responsiveness to ether stress in cholestasis, we administered corticotropin-releasing factor (CRF) and measured hypothalamic content, mRNA levels and in vitro secretion of CRF and arginine vasopressin (AVP), the two principal secretagogues of ACTH. In BDR animals, ACTH responses to CRF were decreased and hypothalamic content of CRF and CRF mRNA expression in the paraventricular nucleus were decreased by 25 and 37%, respectively. Furthermore, CRF release from hypothalamic explants of BDR rats was 23% less than that of controls. In contrast to CRF, hypothalamic content of AVP was 35% higher, AVP mRNA in the paraventricular nucleus was increased by 6.6-fold, and hypothalamic explant release of AVP was 24% higher in BDR rats than in control animals. Pituitary ACTH contents were similar in BDR and sham resected rats, but higher than unoperated controls. These findings demonstrate that acute cholestasis in the rat is associated with suppression of hypothalamic-pituitary-adrenal axis responsiveness to stress and demonstrate a dissociation between mechanisms of ACTH regulation mediated by CRF and AVP. 相似文献
75.
本文用高效液相色谱分离、液闪测定放射性的方法,测定了兔口服炔诺酮肟(NETO)和炔诺酮(NET)的血浓,并比较了二者的药代动力学参数。结果表明:二者吸收迅速,从血中的消除均呈快慢两个时相。NETO在兔体内一部分迅速转变为NET,另一部分则以原药形式存在,24 h内NETO与其代谢产物NET在血清中的浓度大致各占一半。兔口服NETO与NET后,血浓—时间曲线符合二室模型,NETO的达峰时间比NET短,二者有显著差异(P<0.05),其它动力学参数无明显差异(P>0.05)。 相似文献
76.
Cerebrospinal fluid corticotropin-releasing hormone in depression: relationship to noradrenergic function 总被引:2,自引:0,他引:2
We investigated the neurotransmitter regulation of corticotropin-releasing hormone (CRH). Among 21 depressed patients cerebrospinal fluid (CSF) levels of CRH significantly correlated with urinary outputs of norepinephrine and its major metabolites, and there were trends for significant correlations with both CSF and plasma levels of norepinephrine. These results suggest that CRH may be associated with the dysregulation of the norepinephrine system that is found in desperation. 相似文献
77.
78.
79.
Flexible tantalum stents implanted in aortas and iliac arteries: effects in normal canines 总被引:2,自引:0,他引:2
Barth KH; Virmani R; Strecker EP; Savin MA; Lindisch D; Matsumoto AH; Teitelbaum GP 《Radiology》1990,175(1):91-96
Vascular endoprostheses made of knitted tantalum wire and expanded over angioplasty balloons were placed into aortas or iliac arteries of 14 normal dogs. Twelve stents were placed into the infrarenal abdominal aorta and two stents in the left common iliac arteries by the left carotid artery approach. To firmly expand the stent against the vascular wall, nominal stent sizes 0.5-1.0 mm larger than the measured arterial diameter were required. Arteriography performed at specified follow-up intervals showed no evidence of thrombi or emboli; all side branches (lumbar arteries) covered by the stents remained patent. Vascular diameter decreased minimally at 8 and 26 weeks, associated with histopathologic evidence of neointimal buildup. This buildup was highest at 8 weeks (mean, 313 microns) and was slightly less at 26 weeks (mean, 223 microns). Almost complete coverage by endothelium was seen as early as 3 weeks. It is concluded that the flexible tantalum wire stents are well tolerated by the arterial wall and become quickly endothelialized. No excessive neointimal buildup was observed during the 6-month study. 相似文献
80.
The corticotropin-releasing hormone stimulation test in patients with panic disorder 总被引:4,自引:0,他引:4
P P Roy-Byrne T W Uhde R M Post W Gallucci G P Chrousos P W Gold 《The American journal of psychiatry》1986,143(7):896-899
Eight patients with panic disorder had significantly lower ACTH and cortisol responses to corticotropin-releasing hormone and a significantly lower ratio of ACTH to cortisol response than 30 normal control subjects. These responses resemble those previously reported for depressed patients except that they occurred in the face of significantly elevated basal cortisol and ACTH levels. These results suggest that patients with panic disorder have an element of chronic hypercortisolemia, like depressed patients, but also a more acute perturbation in ACTH secretion, not previously seen in depressed patients. 相似文献