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Klinefelter's syndrome is a disorder of gonadal development and typically reveals a 47,XXY karyotype although mosaic forms also occur. Azoospermia is a common feature, but severe oligozoospermia and fertility have been reported. In this study, we have used intracytoplasmic sperm injection (ICSI) to achieve a live twin birth using spermatozoa from a 47,XXY man who has occasional spermatozoa present in the ejaculate. Spermatozoa were obtained from multiple ejaculates and frozen prior to commencing IVF treatment. Nine good quality embryos developed from the injection of 13 oocytes. All nine embryos were frozen. The initial transfer of two frozen-thawed embryos was unsuccessful. In the following cycle, the transfer of two additional frozen-thawed embryos resulted in the delivery of normal, healthy male and female twins. Five embryos remain frozen. It has generally been thought that the germ cells of 47,XXY men are unable to proceed through meiosis. Any spermatozoa produced have been assumed to come from a normal germ cell and therefore likely to have a normal karyotype. However, recent evidence suggests that meiosis of 47,XXY germ cells may be possible. Whether spermatozoa in these men arise from meiosis of 47,XXY germ cells, or from germ cells which have attained a normal karyotype by loss of an X chromosome, is unclear. Any risks in using spermatozoa from these patients have not yet been established. Patients need to be advised accordingly, and preimplantation or prenatal diagnosis should be considered. A cautious approach to the treatment of these patients is therefore warranted.   相似文献   
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Of all patients in a hospital environment, trauma patients may be particularly at risk for developing (device‐related) pressure ulcers (PUs), because of their traumatic injuries, immobility, and exposure to immobilizing and medical devices. Studies on device‐related PUs are scarce. With this study, the incidence and characteristics of PUs and the proportion of PUs that are related to devices in adult trauma patients with suspected spinal injury were described. From January–December 2013, 254 trauma patients were visited every 2 days for skin assessment. The overall incidence of PUs was 28·3% (n = 72/254 patients). The incidence of device‐related PUs was 20·1% (n = 51), and 13% (n = 33) developed solely device‐related PUs. We observed 145 PUs in total of which 60·7% were related to devices (88/145). Device‐related PUs were detected 16 different locations on the front and back of the body. These results show that the incidence of PUs and the proportion of device‐related PUs is very high in trauma patients.  相似文献   
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血清骨唾液酸蛋白的生物变异性研究   总被引:3,自引:0,他引:3       下载免费PDF全文
目的 骨唾液酸蛋白(Bone sialoprotein,简称BSP)是由成骨细胞分泌的一种非胶原蛋白质,反映骨转换和骨形成的指标。最近研究认为:血清BSP浓度可反映破骨细胞活性和骨吸收过程,也可能是一个骨吸收指标。本实验测定了血清BSP在人体内的生物变异性。方法 采用RIA 法测定了290例不同性别和年龄的正常人血清BSP的正常值,血清BSP的天-天变异性及24 h 生物周期。 结果 在儿童组血清BSP正常水平明显高于成人组,其最高值在新生儿期和青春期。绝经后妇女其血清浓度比绝经前妇女水平明显升高(P< 0.05)。血清BSP在每天同一时间的波动范围在 7.3% 至17.7% (平均11.7% )。24 h 内有一个明显的生物周期性变化,表现为峰值在凌晨4~8 时,然后逐渐下降直到午后14时为最低。其生物周期的最大波幅为±20% ,(平均血浓度为10.5 ng/m l)。结论 血清BSP反映了骨转换的生理变化与年龄有明显相关性,其血清水平24 h 内有一个明显的生物周期,而天与天之间变异性较小。  相似文献   
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Background  

Although pulsed electromagnetic field (PEMF) stimulation may be clinically beneficial during fracture healing and for a wide range of bone disorders, there is still debate on its working mechanism. Mesenchymal stem cells are likely mediators facilitating the observed clinical effects of PEMF. Here, we performed in vitro experiments to investigate the effect of PEMF stimulation on human bone marrow-derived stromal cell (BMSC) metabolism and, specifically, whether PEMF can stimulate their osteogenic differentiation.  相似文献   
57.
陆金春等[1]所著的"中国118家实验室精液分析状况的调查"一文主要回顾了当前在中国采用的精液分析方法.  相似文献   
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AIM:To investigate the 10-year results of treating low rectal cancer by a single surgeon in one institution.METHODS:From Oct 1998 to Feb 2009,we prospectively followed a total of 62 patients with cT2-4 low rectal cancer with lower tumor margins measuring at 3 to 6 cm above the anal verge.All patients received neoadjuvant chemoradiation(CRT) for 6 wk.Among them,85% of the patients received 225 mg/m2/d 5-fluorouracil using a portable infusion pump.The whole pelvis received a total dose of 45 Gy of irradiation in 25 fractions over 5 wk.The interval from CRT completion to surgical intervention was planned to be approximately 6-8 wk.Total mesorectal excision(TME) and routine defunctioning stoma construction were performed by one surgeon.The distal resection margin,circumferential resection margin,tumor regression grade(TRG) and other parameters were recorded.We used TRG to evaluate the tumor response after neoadjuvant CRT.We evaluated anal function outcomes using the Memorial Sloan-Kettering Cancer Center anal function scores after closure of the defunctioning stoma.RESULTS:The median distance from the lower margin of rectal cancer to the anal verge was 5 cm:6 cm in 9 patients,5 cm in 32 patients,4 cm in 10 patients,and 3 cm in 11 patients.Before receiving neoadjuvant CRT,45 patients(72.6%) had a cT3-4 tumor,and 21(33.9%) patients had a cN1-2 lymph node status.After CRT,30 patients(48.4%) had a greater than 50% clinical reduction in tumor size.The final pathology reports revealed that 33 patients(53.2%) had a ypT3-4 tumor and 12(19.4%) patients had ypN1-2 lymph node involvement.All patients completed the entire course of neoadjuvant CRT.Most patients developed only Grade 1-2 toxicities during CRT.Thirteen patients(21%) achieved a pathologic complete response.Few post-operative complications occurred.Nearly 90% of the defunctioning stomas were closed within 6 mo.The local recurrence rate was 3.2%.Pathologic lymph node involvement was the only prognostic factor predicting disease recurrence(36.5% vs 76.5%,P = 0.006).Ne  相似文献   
59.
Renal cell carcinoma (RCC) is the most common neoplasm of the kidney. Increasing evidence suggests that microRNAs are dysregulated in RCC and are important factors in RCC pathogenesis. miR-21 is a known oncogene with tumor-promoting effects in many types of cancer. In this study, we analyzed miR-21 in 121 cases of healthy kidney and different RCC subtypes, including clear cell (ccRCC), papillary (pRCC), chromophobe (chRCC), and oncocytoma. Total RNA was extracted, and the expression of miR-21 was measured with real-time quantitative RT-PCR using miR-21-specific probes. The expression of miR-21 was significantly up-regulated in RCC compared with healthy kidney. There was a significant difference in the expression levels between RCC subtypes, with the highest levels of expression in ccRCC and pRCC subtypes. miR-21 expression distinguished ccRCC and pRCC from chRCC and oncocytoma with 90% specificity (95% CI, 63.9% to 98.1%) and 83% sensitivity (95% CI, 53.5% to 97.6%). Significantly higher miR-21 levels were associated with higher stage and grade. Patients who were miR-21 positive had statistically significant shorter disease-free and overall survival rates. Thus, miR-21 is up-regulated in RCC, and its expression levels can be used as a diagnostic marker to distinguish ccRCC and pRCC from chRCC and oncocytoma. Moreover, it has potential as a prognostic marker in RCC, although it is not independent of tumor stage and grade.  相似文献   
60.
用乙酰葡萄糖异硫氰酸酯(GITC)作柱前手性衍生化试剂,以反相高效液相色谱法成功地拆分了地佐西平对映异构体。在此基础上建立了地佐西平对映异构体纯度和血药浓度测定方法。已用于测定右旋地佐西平的光学纯度和小鼠血药浓度。  相似文献   
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