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排序方式: 共有1170条查询结果,搜索用时 15 毫秒
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CA von Arnim R Spoelgen ID Peltan M Deng S Courchesne M Koker T Matsui H Kowa SF Lichtenthaler MC Irizarry BT Hyman 《The Journal of neuroscience》2006,26(39):9913-9922
The beta-amyloid (Abeta) precursor protein (APP) is cleaved sequentially by beta-site of APP-cleaving enzyme (BACE) and gamma-secretase to release the Abeta peptides that accumulate in plaques in Alzheimer's disease (AD). GGA1, a member of the Golgi-localized gamma-ear-containing ARF-binding (GGA) protein family, interacts with BACE and influences its subcellular distribution. We now report that overexpression of GGA1 in cells increased the APP C-terminal fragment resulting from beta-cleavage but surprisingly reduced Abeta. GGA1 confined APP to the Golgi, in which fluorescence resonance energy transfer analyses suggest that the proteins come into close proximity. GGA1 blunted only APP but not notch intracellular domain release. These results suggest that GGA1 prevented APP beta-cleavage products from becoming substrates for gamma-secretase. Direct binding of GGA1 to BACE was not required for these effects, but the integrity of the GAT (GGA1 and TOM) domain of GGA1 was. GGA1 may act as a specific spatial switch influencing APP trafficking and processing, so that APP-GGA1 interactions may have pathophysiological relevance in AD. 相似文献
3.
A rare case of congenital lumbar hernia associated with carpus equina varus is described in a week old baby. The treatment is described with limited review of the literature. 相似文献
4.
应用放射配体结合法证实大鼠胸腺内存在降黑素特异结合部位,该结合位点可以满足特异结合部位的基本条件:1.低结合容量;2.高亲和力;3.可饱和性;4.可逆性;5.对降黑素高度特异性。此外,该特异结合位点具昼夜节律;亚细胞分布的研究表明以细胞核含量最高,线粒体次之,并具有年龄依赖性降低,以出生时最高。 相似文献
5.
Kung FT; Chen WJ; Chou HH; Ko SF; Chang SY 《Human reproduction (Oxford, England)》1997,12(8):1649-1653
We report a rare case of early-stage endometrial adenocarcinoma in a 22
year old nullipara with polycystic ovaries undergoing conservative
treatment. Pretreatment evaluation including tumour grade, depth of
myometrial invasion, tumour size, hormone receptor status and flow
cytometric analysis indicated a favourable prognosis. The patient underwent
repeat endometrial curettage and a 6 month period of therapy with megestrol
acetate and tamoxifen. A combination contraceptive pill was then prescribed
to ensure withdrawal of the menstrual cycle thereafter. Now, 1 year after
the last curettage, there is no evidence of disease. During the treatment
period, hysteroscopy allowed for a more precise approach in panoramically
examining the tumour nest in the endometrial cavity, and the subsequent
endometrial response to hormone therapy. Laparoscopy using bulldog clamps
applied to the isthmic portion of the Fallopian tubes prevented i.p. spread
of endometrial tissue from retrograde regurgitation during hysteroscopy.
Laparoscopic ovarian electrocautery resulted in the reduction of abnormal
hypervascularization on the surface of polycystic ovaries postoperatively
but caused a peri-ovarian adhesion complication. It is interesting that
this case posed a unique opportunity to demonstrate the tumour regression
under the assistance of laparoscopy and hysteroscopy.
相似文献
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Subashini Onichandran Thulasi Kumar Yvonne A. L. Lim Nongyao Sawangjaroen Hemah Andiappan Cristina C. Salibay Tan Tian Chye Init Ithoi Julieta Z. Dungca Wan Y. W. Sulaiman Lau Yee Ling Veeranoot Nissapatorn 《Parasitology research》2013,112(12):4185-4191
The objective of this study was to assess the physico-chemical parameters and waterborne parasites in selected recreational lakes from Malaysia. Samples were collected from seven stations of Recreational Lake A (RL-A) and six stations of Recreational Lake B (RL-B). The samples were processed to detect the presence of Giardia spp. and Cryptosporidium spp. using immunomagnetic separation kit, helminth eggs or ova by bright field microscopy and Acanthamoeba spp. by cultivation in non-nutrient agar. Chemical parameters such as ammonia, chlorine, fluoride, nitrate and nitrite and physical parameters such as dissolved oxygen, electrical conductivity, pH, salinity, temperature and total dissolved solid were also measured. Both lakes were freshwater with salinity ranging from 0.05 to 0.09 ppt. Most stations of these lakes were contaminated with Cryptosporidium spp., Giardia spp., Ascaris spp. and hookworm. Schistosoma spp. was found in RL-B only, while Acanthamoeba spp. was found in all stations. Of all sampling sites, station 5 of RL-B is the most contaminated. Linear regression and correlation analysis revealed that Giardia spp. and Schistosoma spp. showed a significant negative correlation with turbidity (p?<?0.01). Based on the preliminary data obtained, it is clearly shown that there is a necessity to implement the detection of waterborne parasites and physico-chemical analysis in Malaysia. Future work on heavy metals (chromium, copper, mercury and zinc) is recommended to enhance the overall water quality monitoring and to take appropriate safety measures to ensure maintenance of good water standards. 相似文献
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Although some bariatric guidelines reserve pre-operative trans-abdominal ultrasonography screening for symptomatic patients and those with elevated liver enzymes, there has yet to exist a general consensus regarding this issue. Some centers still employ its use as a vital step in the workup of the bariatric patient. This study aims to observe the prevalent findings on routine pre-operative trans-abdominal ultrasonography when used as a screening tool prior to laparoscopic sleeve gastrectomy (LSG). All patients undergoing LSG were screened pre-operatively with trans-abdominal ultrasonography. A retrospective study was done of the pre-operative ultrasonography results of patients who underwent LSG at Amiri Hospital from 2008 to 2012. A total of 747 patients were included in the study, with a median age of 36 (15–68). Five hundred ninety (79.0 %) patients were females while 157 (21.0 %) were males, with an overall median body mass index (BMI) of 45 (30–90). Two hundred forty patients (32.1 %) had normal pre-operative ultrasonography results, 83 (11.1 %) were found to have gallstones, 427 (57.2 %) had fatty liver, and 55 (7.4 %) had other pathologies. There was no statistically significant association between BMI and gallstones (p?=?0.545) and BMI and fatty liver (p?=?0.418). Trans-abdominal ultrasonography screening prior to LSG revealed a wide range of findings but does not add significant information to the pre-operative workup of patients undergoing the procedure and should be reserved for indicated patients. 相似文献
10.
Pierre Robin sequence (PRS) describes a small mandible with retrognathia, an elevated and posteriorly positioned tongue, and an associated U-shaped cleft palate. The retracted tongue may obstruct the airway leading to respiratory failure, with failure to thrive and adverse neurodevelopmental outcomes if not addressed. If the airway obstruction cannot be overcome with conservative measures, there are non-surgical and surgical options. A nasopharyngeal prong (NPP) is a non-surgical, temporary treatment that avoids the complications inherent in an operation, especially given the natural history of mandibular growth and improved airway obstruction in PRS. Although the use of a prong requires training, support, and follow up, it effectively bypasses the obstruction in the majority of children with PRS, and allows the child to outgrow the airway obstruction until the prong is no longer required. On average, the prong can be removed between 6 and 12 months of age. 相似文献