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排序方式: 共有9452条查询结果,搜索用时 15 毫秒
1.
Familial risk and heritability of intellectual disability: a population-based cohort study in Sweden
2.
Erika Cecon Anna Ivanova Marine Luka Florence Gbahou Anne Friederich Jean‐Luc Guillaume Patrick Keller Klaus Knoch Raise Ahmad Philippe Delagrange Michele Solimena Ralf Jockers 《Journal of pineal research》2019,66(2)
Melatonin receptors play important roles in the regulation of circadian and seasonal rhythms, sleep, retinal functions, the immune system, depression, and type 2 diabetes development. Melatonin receptors are approved drug targets for insomnia, non‐24‐hour sleep‐wake disorders, and major depressive disorders. In mammals, two melatonin receptors (MTRs) exist, MT1 and MT2, belonging to the G protein‐coupled receptor (GPCR) superfamily. Similar to most other GPCRs, reliable antibodies recognizing melatonin receptors proved to be difficult to obtain. Here, we describe the development of the first monoclonal antibodies (mABs) for mouse MT1 and MT2. Purified antibodies were extensively characterized for specific reactivity with mouse, rat, and human MT1 and MT2 by Western blot, immunoprecipitation, immunofluorescence, and proximity ligation assay. Several mABs were specific for either mouse MT1 or MT2. None of the mABs cross‐reacted with rat MTRs, and some were able to react with human MTRs. The specificity of the selected mABs was validated by immunofluorescence microscopy in three established locations (retina, suprachiasmatic nuclei, pituitary gland) for MTR expression in mice using MTR‐KO mice as control. MT2 expression was not detected in mouse insulinoma MIN6 cells or pancreatic beta‐cells. Collectively, we report the first monoclonal antibodies recognizing recombinant and native mouse melatonin receptors that will be valuable tools for future studies. 相似文献
3.
K Erdmann M Barten 《Zeitschrift für die gesamte innere Medizin und ihre Grenzgebiete》1989,44(20):617-621
The carcinoma of the papilla occupies a special position among the periampullary carcinomas by its favourable prognosis. Responsible for this are the early appearance of symptoms due to the close neighbourhood to the common bile duct and the restriction of the metastasation to the first stage of lymphatic nodes in the majority of cases. Symptoms are jaundice, epigastric pain and decrease of weight. In the carcinoma of the papilla the duodenoscopy with biopsy and ERCP is the method of choice. The reliability of the biopsy is larger, when it is performed after an endoscopic sphincterotomy. For the delimitation of the carcinoma of the papilla against other causes can further be used the hypotensive duodenography, the abdominal computerd tomography, the sonography and the PTC. A curative treatment is possible only surgically. On account of the better long-term results the partial duodenopancreatectomy is to be preferred to the local exstirpation of the papilla. Endoscopic drainages of the biliary tract carried out preoperatively may reduce the lethality of operations. A palliative drainage of the biliary tract on the endoscopic or percutaneous transhepatic way as well as the endoscopic sphincterotomy may improve the patients' quality of life and prolong the survival time, when there are non-resectable tumours or a general inoperability. 相似文献
4.
Stephan Michael Erdmann Bernhardt Sachs Hans F Merk 《American Journal of Contact Dermatitis》2002,13(1):37-38
Phenylephrine is widely used as an ophthalmic drug. However, there are only very few reports on allergic contact dermatitis induced by phenylephrine. In addition, little is known on cross reactivity patterns between the sympathomimetics phenylephrine, epinephrine and ephedrine which share a similar chemical structure. We report on a man who developed allergic contact dermatitis to Neosynerphin POS eyedrops containing phenylephrine hydrochloride. Cross reactivity between phenylephrine, epinephrine and ephedrine was studied by patch testing. Patch tests were performed with the European standard, an ophthalmics and preservatives series, Neosynerphin POS eyedrops, phenylephrine hydrochloride 10% aq., epinephrine and ephedrine (both 1.0 % aq.). Test sites were read after 48, 72 and 168 hours according to the recommendations of the ICDRG. Neosynerphin POS and phenylephrine hydrochloride 10 % aq. gave positive reactions, whereas epinephrine and ephedrine tested negative. Although phenylephrine is an epinephrine analog delayed type hypersensitivity to phenylephrine did not result in cross reactivity with chemically related epinephrine and ephedrine. 相似文献
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Kerstin Schmidt Johannes Hoffend Annette Altmann Ludwig G Strauss Antonia Dimitrakopoulou-Strauss Britta Engelhardt Dirk Koczan J?rg Peter Thomas J Dengler Walter Mier Michael Eisenhut Uwe Haberkorn Ralf Kinscherf 《Journal of nuclear medicine》2006,47(3):543-551
Growth of malignant tumors is dependent on sufficient blood supply. Thus, inhibition of tumor angiogenesis is emerging as a promising target in the treatment of malignancies. Human angiostatin (hANG) is one of the most potent inhibitors of endothelial cell proliferation, angiogenesis, and tumor growth in vivo. However, its mechanisms operating in vivo are not well understood. METHODS: To obtain more information about functional changes in the angiogenic process, we established Morris hepatoma (MH3924A) cell lines expressing hANG (hANG-MH3924A). The effects of hANG expression on proliferation and apoptosis of human umbilical vein endothelial cells (HUVECs) were measured in coculture experiments in vitro. To evaluate changes in tumor perfusion and blood volume, H2 15O and 68Ga-DOTA-albumin (DOTA is 1,4,7,10-tetraazacyclododecane-N,N',N',N'-tetraacetic acid) were used for PET studies in vivo. Additionally, immunohistologic quantification of vascularization, apoptosis, and proliferation as well as gene array analyses were performed. RESULTS: Our in vitro experiments demonstrate reduced proliferation and increased apoptosis in HUVECs when being cocultured with hANG-MH3924A. In support, tumor growth of hANG-MH3924A is diminished by 95% in vivo. However, tumor perfusion and blood volume are increased in hANG-MH3924A corresponding to an increased microvessel density. Furthermore, hANG-transfected tumors show changes in expression of genes related to apoptosis, stress, signal transduction, and metabolism. CONCLUSION: hANG expression leads to inhibition of tumor growth, increased apoptosis, and changes in the expression of multiple genes involved in stress reactions, signal transduction, and apoptosis, which indicates a multifactorial reaction of tumors. An enhanced microvessel density is seen as part of these reactions and is associated with increased perfusion as measured by PET. 相似文献
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9.
I. Kaare Tesdal Werner Jaschke Mathias Bühler Ralf Adamus Thomas Filser Eggert Holm Max Georgi 《Cardiovascular and interventional radiology》1997,20(1):29-37
Purpose To evaluate prospectively our experience with transjugular intrahepatic portosystemic shunt (TIPS) using four different metallic
stents.
Methods Between November 1991 and April 1995, 57 patients (41 men and 16 women; age 35–72 years, mean 54 years) underwent the TIPS
procedure. Techniques for portal vein localization before and during TIPS were fluoroscopy, computed tomography (CT) studies,
wedged hepatic venography, arterial portography, and ultrasound. After predilation we deployed balloon-expandable (n=48) and self-expanding (n=45) metallic stents. Fifteen patients underwent variceal embolization. Initial follow-up angiograms (mean 6.9 months, range
3–24 months) were obtained in 39 of these patients.
Results Fifty-three patients (93%) had successful TIPS placement. The mean decrease in portal pressure was 42.7%. Besides fluoroscopy,
the most helpful techniques for portal vein localization were venography and CT. Residual stenosis (n=1) and late shortening (n=4) of Wallstents resulted in shunt dysfunction. The technical problems encountered with the Palmaz stent resulted from its
lack of flexibility. We combined balloon-expandable and self-expanding stents in 12 patients. The 30-day and late follow-up
(mean 11.9 months) percutaneous reintervention rates were 11.3% and 64.2%, respectively. There were no clinically significant
complications related to the TIPS insertions.
Conclusion An ideal stent does not exist for TIPS, and the authors recommend combining a Palmaz stent with a flexible self-expanding
stent. 相似文献
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