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71.
72.
子宫肌瘤与性激素及细胞凋亡的关系 总被引:2,自引:0,他引:2
1对象和方法 1.1对象随机抽取2001-10/2002-09我科住院行子宫全切术的34例子宫肌瘤患者,其中卵泡期18例,黄体期16例,年龄35~45岁. 术后均经病理证实,在手术前3 mo均未接受过激素治疗,肌瘤大小为3~8 cm3. 自肌瘤瘤体及瘤旁肌层组织各取材1份作配对比较. 瘤体为实验组,肌层为对照组. 鼠抗人ER, PR, PRL-R, Bcl-2 mAb及链霉菌抗生物素蛋白-过氧化物酶(SP)免疫组化试剂盒,均购自福州迈新生物技术开发公司. 相似文献
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74.
Familial corticosteroid-binding globulin deficiency due to a novel null mutation: association with fatigue and relative hypotension 总被引:9,自引:0,他引:9
Torpy DJ Bachmann AW Grice JE Fitzgerald SP Phillips PJ Whitworth JA Jackson RV 《The Journal of clinical endocrinology and metabolism》2001,86(8):3692-3700
Corticosteroid-binding globulin is a 383-amino acid glycoprotein that serves a hormone transport role and may have functions related to the stress response and inflammation. We describe a 39-member Italian-Australian family with a novel complete loss of function (null) mutation of the corticosteroid-binding globulin gene. A second, previously described, mutation (Lyon) segregated independently in the same kindred. The novel exon 2 mutation led to a premature termination codon corresponding to residue -12 of the procorticosteroid-binding globulin molecule (c.121G-->A). Among 32 family members there were 3 null homozygotes, 19 null heterozygotes, 2 compound heterozygotes, 3 Lyon heterozygotes, and 5 individuals without corticosteroid-binding globulin mutations. Plasma immunoreactive corticosteroid-binding globulin was undetectable in null homozygotes, and mean corticosteroid-binding globulin levels were reduced by approximately 50% at 18.7 +/- 1.3 microg/ml (reference range, 30-52 microg/ml) in null heterozygotes. Morning total plasma cortisol levels were less than 1.8 microg/dl in homozygotes and were positively correlated to the plasma corticosteroid-binding globulin level in heterozygotes. Homozygotes and heterozygote null mutation subjects had a high prevalence of hypotension and fatigue. Among 19 adults with the null mutation, the systolic blood pressure z-score was 12.1 +/- 3.5; 11 of 19 subjects (54%) had a systolic blood pressure below the third percentile. The mean diastolic blood pressure z-score was 18.1 +/- 3.4; 8 of 19 subjects (42%) had a diastolic blood pressure z-score below 10. Idiopathic chronic fatigue was present in 12 of 14 adult null heterozygote subjects (86%) and in 2 of 3 null homozygotes. Five cases met the Centers for Disease Control criteria for chronic fatigue syndrome. Fatigue questionnaires revealed scores of 25.1 +/- 2.5 in 18 adults with the mutation vs. 4.2 +/- 1.5 in 23 healthy controls (P < 0.0001). Compound heterozygosity for both mutations resulted in plasma cortisol levels comparable to those in null homozygotes. Abnormal corticosteroid-binding globulin concentrations or binding affinity may lead to the misdiagnosis of isolated ACTH deficiency. The mechanism of the association between fatigue and relative hypotension is not established by these studies. As idiopathic fatigue disorders are associated with relatively low plasma cortisol, abnormalities of corticosteroid-binding globulin may be pathogenic. 相似文献
75.
Perkins SN; Hursting SD; Haines DC; James SJ; Miller BJ; Phang JM 《Carcinogenesis》1997,18(5):989-994
Transgenic mice with both alleles of the p53 tumor suppressor gene product
'knocked out' by gene targeting are susceptible to early development of
tumors, chiefly lymphomas and sarcomas. Compared with the control group,
administration of dehydroepiandrosterone (DHEA) at 0.3% of the diet to male
p53-deficient mice extended their lifespan by delaying death due to
neoplasms (from 105 to 166 days on study, P = 0.002), primarily by
suppressing lymphoblastic lymphoma (from 45 to 6% of neoplastic deaths, P =
0.010). Treatment with a synthetic DHEA analog,
16alpha-fluoro-5-androsten-17-one (compound 8354), at 0.15% of the diet
also increased lifespan, to 140 days for mice that developed tumors (P =
0.037). The effects of these steroids on lifespan and tumor development did
not appear to be strongly related to inhibition of food consumption and
weight gain, in that a group pair-fed with control diet to the reduced food
consumption of the DHEA-treated group developed and died of the same types
of neoplasms at the same rate as the controls fed ad libitum. The
chemopreventive effect of these steroids has been proposed to be due to
suppression of DNA synthesis by inhibition of glucose 6-phosphate
dehydrogenase, the rate-limiting enzyme of the pentose phosphate pathway.
Although DHEA and its analog are strong non- competitive inhibitors of this
enzyme in vitro, treatment with DHEA did not deplete cellular nucleotide
pools in the liver, as would have been predicted. The chemopreventive
effect of DHEA in this model may be due to steroid-induced thymic atrophy
and suppression of T cell lymphoma, permitting these mice to survive long
enough to develop tumors with longer latency.
相似文献
76.
77.
Templeton AW; Johnson JA; Anderson WH; Cook LT; Dwyer SJ d; Preston DF; Lee KR; Rosenthal SJ; Batnitzky S; Levine E 《Radiology》1984,151(2):527-528
The increasing use of digitally formatted imaging systems requires high-quality interactive gray-scale computer raster graphics systems for the management, display, and analog film recording of digital image and alphanumeric information. These systems are a combination of computer hardware and software and implement a set of graphics protocols. This paper describes a set of interactive graphics protocols that has been developed for clinical use. 相似文献
78.
In a patient with primary hyperparathyroidism an attempt was made to ablate a middle mediastinal parathyroid gland by forceful staining with radiographic contrast material. The gland was stained on two separate occasions, two weeks apart. Both times the serum calcium level temporarily fell to the normal range but reverted to abnormal levels. The patient ultimately required surgery for correction of hypercalcemia. The mechanism of staining and possible reasons for failure as well as potential complications are discussed. 相似文献
79.
Activity that appears to be analogous to human suppression burst activity was produced and studied in 11 cats. Three distinct types of activity were identified and arbitrarily labeled as types A, B, and C. Each showed a regular pattern of appearance and disappearance, as well as differential susceptibility to block by barbiturate. Type A was rhythmic activity resembling barbiturate spindles appearing in the early and late stages of a suppression burst episode. It was especially prominent after pentobarbital. Type B activity generally resembled ongoing background activity, except that it was periodically interrupted by brief periods of EEG suppression. Type C activity, brief pleomorphic spike bursts, dominated the EEG and was seen best against a virtually isoelectric recording. It was most resistant to suppression by barbiturate and disappeared from the spontaneous EEG. We suggest that suppression burst as ordinarily conceived is not a single EEG entity but has a substructure which deserves further study. 相似文献
80.