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131.
Choi SW  Roh KY  Chung KW  Kim MR 《Maturitas》2000,35(1):65-69
OBJECTIVES: This study was performed to determine whether skin pigmentation is darkened after hormone replacement therapy (HRT). METHODS: The color of hyperpigmentary lesions and control sites before and after 1, 2, and 3 months of HRT was measured. RESULTS: All of the three tested sites showed no significant pigment alteration in 3 months of follow up after starting HRT (P>0.05). Age, duration of menopause, and sex hormone levels did not correlate with pigmentation level. CONCLUSIONS: Pigmentation changes after HRT are not significantly associated with the treatment. This finding suggests that low-dose estrogen replacement therapy does not induce pigmentation changes alone and that differences in individual susceptibility and end organ responsiveness or other multiple factors in addition to the sex hormone may be responsible for the development and darkening of hyperpigmentary lesions.  相似文献   
132.
A pectoralis quartus muscle and an unusual axillary arch were found on the left side of a female cadaver. The axillary arch was a musculoaponeurotic complex continuous with the iliacal fibers of the latissimus dorsi. The muscular part, together with the tendon of pectoralis major, inserted into the lateral lip of the bicipital groove of the humerus, whereas the aponeurotic part was formed by a fibrous band that extended deep to the pectoralis major to insert into the coracoid process between the attachments of the coracobrachialis and pectoralis minor. The pectoralis quartus originated from the rectus sheath, and joined the inferior medial border of the fibrous band of the axillary arch, at the lateral edge of the pectoralis major. The axillary arch muscle crossed anteriorly the axillary vessels and the brachial plexus. The clinical importance of these muscles is reviewed.  相似文献   
133.
We have used gene expression profiling approaches to identify new molecular targets in various models of lung injury and human lung diseases. Among the many genes that are significantly induced in these studies, cysteine-rich61 (Cyr61) consistently ranks as one of the most significant genes. Here, we use the well-established model of hyperoxia to better understand the function of Cyr61 in acute lung injury. Cyr61, a stress-related immediate-early response gene, has known diverse functions involving angiogenesis, tumorigenesis, and wound repair. It belongs to the newly discovered "CCN" family containing six growth and regulatory factors. We showed that hyperoxia induces Cyr61 expression in a variety of pulmonary cells and in lung tissue in vivo. Loss of function studies, by suppressing Cyr61 expression by siRNA, accelerated lung epithelial cell death after hyperoxia. Gain of function studies, by overexpressing Cyr61, significantly conferred increased resistance to hyperoxia-induced cell death. Moreover, cells overexpressing Cyr61 induce Akt activation. Inhibition of Akt by siRNA abrogated the protective effects of Cyr61-overexpressing cells in response to hyperoxia. Taken together, our data demonstrate that Cyr61 expression provides cytoprotection in hyperoxia-induced pulmonary epithelial cell death and that this effect was in part mediated via the Akt signaling pathway.  相似文献   
134.
To better understand the pathophysiological role of Src protein, a non-receptor protein tyrosine kinase of 60kDa, in the ischemic brain, we investigated the time course and regional distribution of active Src expression by using a specific antibody against Tyr416 phosphorylated Src (phospho-Src) in the rat hippocampus after transient forebrain ischemia. In the hippocampus of the control animals, active Src expression was too low to be detected by immunolabeling. Beginning 4h after reperfusion, active Src expression became evident and, after 1 day, had increased preferentially in the CA field of the hippocampus proper and the dentate gyrus. By day 3, active Src expression markedly increased in the pyramidal cell layer of CA1 and the dentate hilar region in temporal correlation with neuronal cell death occurring in these areas, where cells typical of phagocytic microglia showed phospho-Src immunoreactivity. Double-labeling experiments revealed that cells expressing active Src were microglia that stained for biotinylated lectin derived from Griffonia simplicifolia (GSI-B4). Active Src expression began to decline at day 7 and returned to the basal level by day 14 after reperfusion. These results demonstrate increased phosphorylation of Src in activated microglia of the post-ischemic hippocampus, indicating that Src signaling may be involved in the microglial reaction to an ischemic insult.  相似文献   
135.
136.
Interleukin 15 (IL-15) is an important regulatory cytokine in cellular immunity. In vitro replacement of IL-15 has been shown to enhance immunity in Human immunodeficiency virus type 1 (HIV-1) infected lymphocytes. We evaluated the effect of IL-15 on the survival of peripheral blood mononuclear cells of HIV patients by examining in vitro lymphocyte apoptosis, and correlated the process with Bcl-2 and Fas gene regulation. Peripheral blood mononuclear cells (PBMC) from 21 HIV-infected adults and 24 HIV-seronegative healthy individuals were isolated and cultured to determine the effect of escalating doses of IL-15 (0, 1, 10, 100, 1000 ng/mL) on apoptosis. Lymphocyte proliferation assay with (3H) TdR was measured and Bcl-2 and Fas gene regulation was observed. The results were as follows: 1) IL-15 reduced culture induced lymphocyte apoptosis in HIV patients in a dose dependent manner, and reached a plateau level at a concentration of 100 ng/ml; 2) IL-15 significantly reduced the level of apoptosis after 3 days (14%) and 5 days (15%) of culture in HIV patients, while no difference was observed in HIV (-) donors; 3) The percentage of viable cells among the total number of lymphocytes was significantly enhanced by 25% in HIV patients with IL-15; 4) Bcl-2 expression was decreased in HIV patients (53.9 +/- 12.3%) compared to HIV (-) donors (93.0 +/- 3.7%), and IL-15 increased Bcl-2 expression by 21.2 +/- 5.2% in HIV patients; 5) Fas expression was increased in HIV patients (70.2 +/- 4.6%) compared to HIV (-) donors (32.4 +/- 4.3%), and IL-15 increased Fas expression by 8.4 +/- 1.2% in HIV (-) donors. Our findings indicate that IL-15 may influence immunologic abnormalities in HIV infection, particularly its ability to prevent apoptosis of lymphocytes by suppressing the down-modulation of Bcl-2. This may provide an experimental basis for IL-15 immunotherapy.  相似文献   
137.
Radiologic findings of Mirizzi syndrome with emphasis on MRI   总被引:6,自引:0,他引:6  
We have reported a case of Mirizzi syndrome preoperatively diagnosed using MR cholangiopancreatography. MRCP and T2-weighted image using a single-shot fast spin-echo sequence accurately depicted all components of Mirizzi syndrome, including impacted stone in the neck of the gallbladder compressing the common hepatic duct and wall-thickening of the gallbladder without any evidence of malignancy. The combination of MRCP and T2-weighted image can be counted on to replace conventional modalities of diagnosing Mirizzi syndrome without any loss of diagnostic accuracy.  相似文献   
138.
The favorable effects of estrogen on cardiovascular diseases can be explained by several mechanisms such as changes in serum lipid profiles and thrombogenecity. Estrogen also affects the vascular tone, but there has been no report in which the effect of estrogen was tested comprehensively for several vasoactive substances, especially after long-term administration. Two weeks after bilateral ovariectomy in 8-week old female Sprague-Dawley rats, placebo or 17 beta-estradiol (E2) pellets (0.5 mg; released over 3 weeks) were implanted subcutaneously. Two weeks after pellet implantation, organ chamber experiments were performed using aortae. Compared with control, E2-treated vessels showed impaired endothelium-dependent relaxation to acetylcholine. E2 enhanced the contraction to norepinephrine and U46619 and had no effect on endothelin-1-induced contraction. In contrast, the contraction to angiotensin (AT)-II was inhibited by E2. Northern blot analysis for AT1 receptor expression using cultured aortic smooth muscle cells showed no difference between control and E2-treated cells, suggesting that AT1 receptor downregulation is not the likely mechanism. These results suggest that E2 affects the vascular tone variably according to vasoactive substances.  相似文献   
139.
Sohn JH  Kim DH  Choi NG  Park YE  Ro JY 《Histopathology》2000,37(6):555-560
AIMS: Apoptosis is mediated by apoptosis-specific genes, certain oncogenes and tumour suppressor genes. Caspase-3, a group of cystein proteases, is involved in the induction of apoptosis and has been considered to correlate with apoptosis. The aim of this study was to determine whether caspase-3 is expressed in prostatic carcinoma and benign prostatic hyperplasia, and correlated with the apoptosis. METHODS AND RESULTS: We studied the apoptotic index and caspase-3 immunoreactivity in 40 cases of benign nodular hyperplasia (BPH) and 40 cases of prostate carcinoma (PCA) by in-situ labelling and immunohistochemistry. The mean number of apoptotic bodies in cases with BPH was not significantly different from cases with PCA I (Gleason score 2-4), but samples from patients with PCA II (Gleason score 5-7) and PCA III (Gleason score 8-10) showed a significantly higher apoptotic number than cases with BPH. Positive staining for caspase-3 was seen in 42.5% (17/40) of the BPH, and 27.5% (11/40) of the PCA: PCA I was 41.7% (5/12), PCA II 14.3% (2/14) and PCA III was 28.6% (4/14). CONCLUSIONS: Based on our results, the number of apoptotic bodies was not correlated with the caspase-3 expression and there was no relationship between caspase-3 expression and Gleason score. However, the number of apoptotic bodies was significantly higher in cases with intermediate (Gleason score 5-7) and high-grade (Gleason score 8-10) PCAs than cases with BPH and low-grade PCAs (Gleason score 2-4).  相似文献   
140.
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