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排序方式: 共有4799条查询结果,搜索用时 15 毫秒
91.
Angiotensin II type 1 receptor and ACTH receptor expression in human adrenocortical neoplasms 总被引:1,自引:0,他引:1
Schubert B Fassnacht M Beuschlein F Zenkert S Allolio B Reincke M 《Clinical endocrinology》2001,54(5):627-632
OBJECTIVE: Type 1 angiotensin II (Ang II) receptors transduce most of the known actions of Ang II, including steroidogenesis and trophic actions on the adrenal cortex. We investigated the type 1 Ang II receptor expression in adrenocortical tissues to define its regulation in adrenocortical neoplasms and to compare its expression with that of the ACTH receptor (ACTH-R). PATIENTS AND MEASUREMENTS: Poly A RNA was extracted from tumour tissue and electrophoresed through a 1.0% agarose gel, blotted and hybridized with alpha32P-CTP labelled PCR generated type 1 Ang II receptor cDNA probe. Receptor autoradiography was performed on slices from normal adrenals and tumour tissue by incubation with 125I-Sar1, Ile8-Ang II with and without pretreatment with cold Ang II or with the selective type 1 receptor antagonist losartan. RESULTS: Ang II type 1 receptor mRNA was high in cortisol producing (CPA; n = 5) and aldosterone producing (APA; n = 4) adenomas (normal adrenals 100 +/- 12% vs. 180 +/- 16% in CPA and 154 +/- 26% in APA, mean +/- SEM), but was low in nonfunctioning adenomas (NFA; n = 2; 2 +/- 1%). ACTH receptor mRNA followed a similar pattern (CPA 178 +/- 17, APA 196 +/- 30, NFA 0%, carcinomas 56 +/- 11%) with a good correlation between Ang II type 1 receptor and ACTH-R mRNA of r = 0.692, P = 0.0019. Receptor autoradiography in normal adrenals demonstrated Ang II type 1 receptors predominantly in the zona glomerulosa. In tumour tissue, mainly type 1 receptor expression was found confirming the Northern blot data. CONCLUSIONS: Angiotensin II type 1 receptor and ACTH receptor expression seems to be correlated with the functional status of adrenocortical tumours, suggesting regulation by similar factors. The predominant receptor expressed in adrenocortical tumours is the Angiotensin II type 1 receptor whereas type 2 receptor expression is minimal. 相似文献
92.
Douglas M. Simon John P. Cello Jorge Valenzuela Richard Levy Gordon Dickerson Richard Goodgame Michael Brown Kip Lyche W.Jeffrey Fessel James Grendell C.Mel Wilcox Nezam Afdhal Ronald Fogel Vonda Reeves-Darby John Stern Owen Smith Frank Graziano Douglas Pleakow Timothy Flanigan Timothy Schubert Mark Loveless Larry Eron Paul Basuk Maurizio Bonacini Jan Orenstein 《Gastroenterology》1995,108(6):1753-1760
Diarrhea is a significant problem in patients with acquired immunodeficiency syndrome (AIDS). The aim of this study was to determine octreotide effectiveness in refractory AIDS-associated diarrhea. In a 3-week protocol, 129 patients with a stool weight of >500 g/day despite standard antidiarrheal therapy were randomized to receive octreotide or placebo (3:2 ratio). Octreotide dose was increased 100 μg weekly to a maximum of 300 μg three times a day based on weekly 72-hour stool collections. Subsequently, patients received open-label octreotide at doses of up to 500 μg three times a day. A 30% decrease in stool weight defined response. After 3 weeks, 48% of octreotide- and 39% of placebo-treated patients had responded (P = 0.43). At 300 μg three times a day, 50% of octreotide- and 30.1% of placebo-treated patients responded (P = 0.12). At a baseline stool weight of 1000–2000 g/day, 57% of octreotide- and 25% of placebo-treated patients responded (P = 0.06). Response rates based on CD4 counts, diarrhea duration, body weight, human immunodeficiency virus risk factor, and presence or absence of pathogens showed no benefit of octreotide. Adverse events were more frequent in the octreotide-treated group. In the doses studied, octreotide was not more effective than placebo in patients with refractory AIDS-associated diarrhea. This lack of effectiveness may be attributable to inadequate sample size, doses, and duration of study treatment. 相似文献
93.
Felix Zwicker Benedict Swartman Falk Roeder Florian Sterzing Henrik Hauswald Christian Thieke Klaus-Josef Weber Peter E. Huber Kai Schubert Jürgen Debus Klaus Herfarth 《Journal of radiation research》2015,56(2):239-247
In radiotherapy, in vivo measurement of dose distribution within patients'' lymphocytes can be performed by detecting gamma-H2AX foci in lymphocyte nuclei. This method can help in determining the whole-body dose. Options for risk estimations for toxicities in normal tissue and for the incidence of secondary malignancy are still under debate. In this investigation, helical tomotherapy (TOMO) is compared with step-and-shoot IMRT (SSIMRT) of the prostate gland by measuring the dose distribution within patients'' lymphocytes. In this prospective study, blood was taken from 20 patients before and 10 min after their first irradiation fraction for each technique. The isolated leukocytes were fixed 2 h after radiation. DNA double-stranded breaks in lymphocyte nuclei were stained immunocytochemically using anti-gamma-H2AX antibodies. Gamma-H2AX foci distribution in lymphocytes was determined for each patient. Using a calibration line, dose distributions in patients'' lymphocytes were determined by studying the gamma-H2AX foci distribution, and these data were used to generate a cumulative dose–lymphocyte histogram (DLH). Measured in vivo (DLH), significantly fewer lymphocytes indicated low-dose exposure (<40% of the applied dose) during TOMO compared with SSIMRT. The dose exposure range, between 45 and 100%, was equal with both radiation techniques. The mean number of gamma-H2AX foci per lymphocyte was significantly lower in the TOMO group compared with the SSIMRT group. In radiotherapy of the prostate gland, TOMO generates a smaller fraction of patients'' lymphocytes with low-dose exposure relative to the whole body compared with SSIMRT. Differences in the constructional buildup of the different linear accelerator systems, e.g. the flattening filter, may be the cause thereof. The influence of these methods on the incidence of secondary malignancy should be investigated in further studies. 相似文献
94.
Left atrial thrombus two years after placement of a left atrial appendage closure device: Unexplored area of the Watchman 下载免费PDF全文
David H Yoo MD Brian Clark MD Daniel Nguyen MD Timm‐Michael Dickfeld MD PhD Andrew S Zohlman MD Libin Wang MD Vincent Y See MD 《Pacing and clinical electrophysiology : PACE》2018,41(7):870-871
A 72‐year‐old man who underwent a left atrial appendage (LAA) closure device 2 years ago presented with atrial flutter with rapid ventricular rate and was referred for cardioversion. Precardioversion transesophageal echocardiogram showed left atrial thrombus and therefore the procedure was aborted. Currently, there is no guideline on imaging surveillance or anticoagulation in patients with LAA closure device who develop intracardiac thrombus after the initial 6‐month surveillance period. 相似文献
95.
96.
Timm Harder Sebastian Maurer-Stroh Anne Pohlmann Elke Starick Detlef H?reth-B?ntgen Karin Albrecht Gunter Pannwitz Jens Teifke Vithiagaran Gunalan Raphael T.C. Lee Carola Sauter-Louis Timo Homeier Christoph Staubach Carola Wolf Günter Strebelow Dirk H?per Christian Grund Franz J. Conraths Thomas C. Mettenleiter Martin Beer 《Emerging infectious diseases》2015,21(5):860-863
Highly pathogenic avian influenza (H5N8) virus, like the recently described H5N8 strain from Korea, was detected in November 2014 in farmed turkeys and in a healthy common teal (Anas crecca) in northeastern Germany. Infected wild birds possibly introduced this virus. 相似文献
97.
Regulation of gastric somatostatin secretion in the mouse by luminal acidity: a local feedback mechanism 总被引:3,自引:0,他引:3
The present study was designed to determine whether somatostatin secretion induced by histamine or pentagastrin in the isolated luminally perfused mouse stomach was a direct effect of the secretagogues on gastric somatostatin cells or an indirect effect mediated by the increase in luminal acidity. Perfusion of the lumen with exogenous acid (80-480 nmol/min) caused an increase in somatostatin secretion in proportion to the increase in luminal acidity. The increase in somatostatin secretion was resistant to tetrodotoxin and attained maximal levels (61.6% +/- 8.7% above basal level) similar to those elicited by maximal doses of secretagogues. Conversely, neutralization of basal acid secretion with bicarbonate (20-160 nmol/min) caused a decrease in somatostatin secretion in proportion to the decrease in luminal acidity. Similarly, neutralization of the secretagogue-induced increments in acid secretion with bicarbonate or inhibition of the increments with cimetidine abolished the corresponding increments in somatostatin secretion. It is proposed that acid-induced release of somatostatin in proximity to parietal cells serves as a negative feedback mechanism restraining acid secretion. 相似文献
98.
Fluoroquinolones are known to penetrate well into the infectious foci such as lung mucosa, epithelial lining fluid and alveolar macrophages achieving higher target site concentrations than the corresponding serum levels. In order to integrate the in vitro antibacterial activity and pharmacokinetics of moxifloxacin and levofloxacin, their bactericidal efficacy was assessed by simulating human serum and lung tissue concentrations using Streptococcus pneumoniae, Staphylococcus aureus and Klebsiella pneumoniae as indicator organisms. The bacteria were exposed to fluctuating moxifloxacin and levofloxacin concentrations simulating the drug levels in serum, lung mucosa, epithelial lining fluid and alveolar macrophages. The following parameters were deduced from the kill curves: area under the bactericidal kill curve normalized to the initial inoculum (AUBKC norm), the time needed to reduce the inoculum by 3 log(10) titers, and the initial bactericidal activity. In general, all these three parameters were for all the bacterial isolates having been exposed to moxifloxacin concentration dependent. In contrast, beyond a levofloxacin concentration of optimal bactericidal effect, higher drug concentrations did not further augment the bactericidal activity of levofloxacin. These data demonstrate that not all fluoroquinolones share the same pharmacodynamic targets needed to maximize their antibacterial effect. 相似文献
99.
Talc in the liver is highly suggestive of intravenous drug abuse. We report three patients in whom finding talc or talc granuloma on liver biopsy led to the diagnosis of unsuspected i.v. drug abuse. There follows a discussion of the pathogenesis, laboratory and clinical features, and liver pathology of talc liver. 相似文献
100.
Decrease in Ornithine Decarboxylase Activity after Eradication of Helicobacter pylori 总被引:3,自引:0,他引:3
Khalid Alam M.D. Freda L. Arlow M.D. Chan K. Ma M.D. Timothy T. Schubert M.D. 《The American journal of gastroenterology》1994,89(6):888-893
Objective: Our aim was to determine whether gastric mucosal ODC activity is altered after successful eradication of HP. Recent reports have suggested that Helicobacter pylori (HP) infection of the stomach is associated with the development of gastric cancer. Gastrointestinal cancers usually do not arise de novo; a series of mucosal changes leading to neoplastic transformation and degrees of dysplasia are believed to precede the development of cancer. These conditions are associated with increased cellular proliferation. Ornithine decarboxylase (ODC) activity is induced by factors that stimulate cellular proliferation, and has been shown to be elevated in gastrointestinal neoplasia, including gastric cancer. Methods: Gastric antral and body biopsies were obtained from 17 HP-positive patients at endoscopy, for ODC activity and histology (including Warthin Starry stain) before and 4–6 wk after successful triple therapy. Results: Patients included 12 males and five females, with a mean age of 55 yr (27–73 yr). Mean ODC activity (in pmol CO2 /mg protein/h) was significantly decreased after eradication of HP, compared with pretreatment levels in antral (147 ± 26 vs . 80 ± 15) and body mucosa (76 ± 21 vs . 20 ± 5) ( p < 0.05). Conclusion: Successful eradication of HP decreases mucosal proliferative activity, as reflected by decreased ODC activity. We speculate that by decreasing mucosal proliferative activity, HP eradication may help decrease the subsequent risk of gastric cancer. 相似文献