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Endothelin is a peptide reported to be one of the most potent vasoconstrictors known. Presumably, endothelin could play a role in the physiological regulation of blood pressure in healthy or hypertensive people. We have studied a normal restriction fragment length polymorphism (RFLP) at the endothelin-I (EDN1) locus detected with the restriction enzyme TaqI. In three different series comprising 166, 120 and 207 unrelated individuals, we found no evidence for association between genotype in this polymorphism and level of systolic or diastolic blood pressure. In two series of 156 and 117 monozygotic (MZ) twin pairs, respectively, there was no difference between genotypes in within-pair variation in systolic or diastolic blood pressure. Thus neither "level gene" nor "variability gene" effects of normal genes at the EDN1 locus could be detected with the polymorphism analyzed, in healthy population samples.  相似文献   
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血清CA125检测在子宫内膜癌中的价值   总被引:3,自引:0,他引:3  
目的探讨血清CA125在子宫内膜癌中的价值.方法选取1992年3月~2002年3月在北京大学第一附属医院、北京大学人民医院住院经手术治疗的子宫内膜癌患者141例,术前及随访中用放射免疫法测定血清CA125水平,CA125≥35 U/ml 为阳性结果.对其中14例行子宫内膜癌组织CA125免疫组化方法检测.收集患者的临床病理资料,分析CA125与这些资料的关系以及复发患者复发前后CA125变化.结果 CA125免疫组化检测14例均呈阳性,阳性细胞着色率与血清CA125之间无明显相关.141例患者术前血清CA125阳性32例(22.7%), Ⅰ、Ⅱ、Ⅲ和Ⅳ期患者血清CA125阳性(阳性率)分别为11例(12.1%)、6例(31.6%)、12例(46.2%)和3例(60.0%). 血清CA125阳性率随子宫内膜癌期别的增加而升高.深肌层浸润、宫颈受累、附件转移、腹腔洗液细胞学阳性、盆腔淋巴结转移及宫内肿瘤病灶≥2 cm者,血清CA125阳性率增加.随访中13例复发,其中9例术前血清CA125>35 U/ml者复发时均伴血清CA125水平升高,而另4例术前血清CA125正常者,复发后血清CA125水平仍正常.结论子宫内膜癌患者术前血清CA125的测量有助于了解肿瘤的侵犯范围.术前血清CA125水平异常的子宫内膜癌患者,术后定期复查血清CA125水平,将有助于子宫内膜癌病情的监测.  相似文献   
65.
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Abstract: New analogues of deltorphin I (DT I), in which the Phe residue in position 3, and the Val residue in position 5 or 6 are replaced with respective amphiphilic α‐hydroxymethylamino acid residues (HmAA), were synthesized and tested for receptor affinity and selectivity to μ and δ opioid receptors. The analogue with (R)‐HmPhe at position 3 lost receptor selectivity, as a result of a partial decrease of affinity to δ and a significant increase of affinity to μ receptors. In contrast, an analogue with (S)‐HmPhe in the same position, was very potent and more specific to δ receptors than parent DT I. The analogue with (R)‐HmVal at position 5 expressed higher δ affinity and selectivity than parent DT I. The analogue with other possible isomer (S)‐HmVal was less selective for δ opioid receptors, as a result of decreasing affinity to δ and increasing affinity to μ receptors. The analogues with (R)‐ or (S)‐HmVal in position 6 expressed equally low receptor affinity and selectivity. The data obtained support a previously proposed model of active conformation of deltorphins.  相似文献   
67.
Serum CA125 concentrations measured before and during chemotherapy may provide additional information for prognostic assessment of patients with epithelial ovarian cancer (EOC), and enable discrimination between patients who are likely to benefit from further therapy and those who will not. Medical records of 40 patients with advanced EOC, treated at the Department of Obstetrics and Gynecology of the University Hospital Nijmegen between July 1984 and April 1993, were examined. All patients had primary cytoreductive surgery followed by platinum-based chemotherapy. Serum samples were obtained before surgery and during chemotherapy. Follow-up information and patient and tumor characteristics were abstracted from medical records until December 1, 1994. By using multivariate Cox proportional hazards models for disease-free and overall survival it was evaluated whether outcome prediction was improved by inclusion of serum CA125 quantitations.
  Only FIGO stage and extent of residual tumor were significant independent prognostic factors before the start of chemotherapy. When such regression models were constructed after subsequent courses of chemotherapy, serum CA125 measurements conducted after each of the first three chemotherapy courses improved the prediction of disease-free survival. Prediction of overall survival was improved by inclusion of serum CA125 measurements after courses 1–6. Inclusion of serum CA125 measurements during chemotherapy improved prognostic assessment of patients with advanced EOC.  相似文献   
68.
Two distinct hereditary defects, vitamin D-dependent rickets type I (VDDR I) and type II (VDDR II), have been recognized in vitamin D metabolism. VDDR I is suggested to be a deficiency of the renal 25-hydroxyvitamin D (25(OH)D)-1α-hydroxylase. Muscle weakness and rickets are the prominent clinical findings. A normal physiologic dose of 1α-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 is sufficient to maintain remission of rickets in this disorder. VDDR II consists of a spectrum of intracellular vitamin D receptor (VDR) defects and is characterized by the early onset of severe rickets and associated alopecia. This can be attributed to mutations in the VDR gene. Massive doses of vitamin D analogs and calcium supplementation is usually required for the treatment; however, the response to therapy is sometimes variable.  相似文献   
69.
黄连种子胚后熟期间的生理生化变化及激素的影响   总被引:7,自引:0,他引:7  
黄连种子需要在低温条件下才能解除休眠。本文对黄连种子层积在室外和冰箱两种条件下,种胚后熟过程中的淀粉酶活性及DNA、蛋白质的变化规律作了测定,并对ABA处理后种子的生理生化变化作了研究。  相似文献   
70.
Background Changes in interstitial collagen in human oral cancer have not yet been fully studied. We examined the relationship between the degree of interstitial collagen deposition at the invading edge of the tumor, and the clinical and pathologic findings in oral squamous cell carcinoma. We also investigated the therapeutic implication of the changes in distribution patterns of collagen deposition by comparing biopsy specimens and surgical specimens. Methods Immunohistochemical staining was performed by the streptavidin-biotin method using antibody against human type I collagen for visualizing interstitial collagen in 50 biopsy and 45 surgical specimens. Results Carcinomas with scanty interstitial collagen in biopsy specimens tended to have highly malignant characteristics. Large carcinomas with scanty deposition both in biopsy and surgical specimens were likely to have positive resection margins in spite of radical surgery. Conclusion Immunostaining patterns for type I collagen of oral squamous cell carcinomas can provide information of importance in determining safe resection margins.  相似文献   
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