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Chlamydia trachomatis is currently the most common sexually transmitted disease in the United States. The prevalence in pregnant women ranges between 2% and 47%. It is well known that C trachomatis can be transmitted from the genital tract of an infected mother to her newborn infant, causing conjunctivitis or pneumonia or both, along with their longstanding complications. A review of the literature failed to show, however, conclusive evidence of transmission of infection to the newborn infant when the infant was born by cesarean section with intact amniotic membranes. We present a case of a young black woman with a history of chlamydia cervicitis during pregnancy whose infant was delivered by cesarean section because of failure to progress. She gave birth to a healthy term infant who developed ophthalmia neonatorum on the 3rd day of life. Examinations of conjunctival scrapings with direct fluorescent staining (chlamydia MicroTrak) performed on the 1st and 3rd day of life were positive. The initial test was performed because of the maternal history. The infant was mildly symptomatic at the time the study was repeated for confirmation. Our findings strongly suggest the possibility of either transmembrane or transplacental route of infection in the pathogenesis of neonatal chlamydia infection. Further study is needed to confirm this possibility.  相似文献   
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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   
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Anterior cervical discectomy and fusion (ACDF) may be considered to be the gold standard for treatment of symptomatic degenerative disc disease within the cervical spine. However, fusion of the segment may result in progressive degeneration of the adjacent segments. Therefore, dynamic stabilization procedures have been introduced. Among these, artificial disc replacement by disc prosthesis seems to be promising. However, to be so, segmental motion must be preserved. This, again, is very difficult to judge and has not yet been proven. The aim of the current study was to first analyse the segmental motion following artificial disc replacement using a disc prosthesis. A second aim was to compare both segmental motion as well as clinical result to the current gold standard (ACDF). This is a prospective controlled study. Twenty-five patients with cervical disc herniation were enrolled and assigned to either study group (receiving a disc prosthesis) or control group (receiving ACDF, using a cage with bone graft and an anterior plate.) Radiostereometric analysis was used to quantify intervertebral motion immediately as well as 3, 6, 12 and 24 weeks postoperatively. Further, clinical results were judged using visual analogue scale and neuro-examination. Cervical spine segmental motion decreased over time in the presence of disc prosthesis or ACDF. However, the loss of segmental motion is significantly higher in the ACDF group, when looked at 3, 6, 12 and 24 weeks after surgery. We observed significant pain reduction in neck and arm postoperatively, without significant difference between both groups (P > 0.05). Cervical spine disc prosthesis preserves cervical spine segmental motion within the first 6 months after surgery. The clinical results are the same when compared to the early results following ACDF.  相似文献   
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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   
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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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BackgroundThe NCCN guidelines recommend active surveillance (AS) as an option for the initial management of cT1a 0-2 cm renal lesions. However, data about comparison between renal cell carcinoma (RCC) 0-2 cm vs. 2.1-4 cm are scarce.MethodsWithin the Surveillance, Epidemiology, and End Results database (2002–2016), 46,630 T1a NanyMany stage patients treated with nephrectomy were identified. Data were tabulated according to histological subtype, tumor grade (low [LG] vs. high [HG]), as well as age category and gender. Additionally, rates of synchronous metastases were quantified.ResultsOverall, 69.3 vs. 74.1% clear cell, 21.4 vs. 17.6% papillary, 6.9 vs. 6.8% chromophobe, 2.0 vs. 1.1% sarcomatoid dedifferentiation, 0.2 vs. 0.2% collecting duct histological subtype were identified for respectively 0-2 cm and 2.1-4 cm RCCs. In both groups, advanced age was associated with higher rate of HG clear cell and HG papillary histological subtype. In 0-2 cm vs. 2.1-4 cm RCCs, 13.8% vs. 20.2% individuals operated on harbored HG tumors and were more prevalent in males. Lower synchronous metastases rates were recorded in 0-2 cm RCC and ranged from 0 in respectively multilocular cystic to 0.9% in HG papillary histological subtype. The highest synchronous metastases rates were recorded in sarcomatoid dedifferentiation histological subtype (13.8% and 9.7%) in both groups.ConclusionsRelative to 2.1-4 cm RCCs, 0-2 cm RCCs harbored lower rates of HG tumors, lower rates of aggressive variant histology and lower rates of synchronous metastases. The indications and demographics of patients selected for AS may be expanded in the future to include younger and healthier patients.  相似文献   
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