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51.
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   
52.
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   
53.
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   
54.

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   
55.
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   
56.
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   
57.
58.
目的:观察脊髓损伤后不同时间移植真皮多能干细胞对大鼠运动功能修复的影响。方法:实验于2006-06/2007-03在第三军医大学生理学教研室完成。①实验材料:实验动物2~4月龄SPF级SD大鼠,体质量(210±40)g,雌雄不限,由第三军医大学实验动物中心提供。真皮多能干细胞为第三军医大学防原医学系从SD大鼠真皮中提取和分离。②实验方法:将42只SD大鼠在L4水平制成脊髓全横断损伤模型。将动物随机分为对照组(n=6)、真皮多能干细胞移植组(n=36)。真皮多能干细胞移植组又分为6个时间点:损伤后1,4,7,10,14,21d移植组,每组6只。各移植组于伤处移植大鼠真皮多能干细胞,而对照组于损伤后7d注射等量磷酸盐缓冲液。③实验评估:分别于移植后1d、1周、4周、8周、12周对各组大鼠进行动物行为学和脊髓诱发电位检测。结果:42只实验大鼠均进入结果分析,无脱落。①动物行为学评分:4周以后各组动物行为学评分比较差异有显著性意义(P<0.05),移植组明显高于对照组(P<0.05),各移植组间比较,以损伤后7,10d移植组动物行为学评分改善最显著。②各组大鼠脊髓诱发电位检查:体感诱发电位和运动诱发电位潜伏期和波幅值于移植后8,12周后明显高于对照组(P<0.05),各移植组间比较,以损伤后7,10d移植组体感诱发电位和运动诱发电位潜伏期和波幅值改善最显著。结论:脊髓损伤后7~14d进行真皮多能干细胞移植可明显改善大鼠后肢的运动功能。  相似文献   
59.
李全  沈旭  邵华武  谢毓元 《药学学报》1995,30(6):471-475
Seventeen compounds having the structure of 2,3-diacetoxy-1,4-bis(3′,5′- dioxo-N4′-substituted piperazinyl methyl)benzene were designed and synthesized based on chelation hypothesis. Their antitumor activities on P388 cells,Hep cells and SGC 7901 cells in vitro were tested. Preliminary results showed that compound 4e has potent antitumor effect against P388 cells and.Hep cells in vitro.  相似文献   
60.
血红素氧合酶-1在器官移植中的保护作用   总被引:4,自引:2,他引:2  
血红素氧合酶(heme oxygenase,HO)是体内唯一一种催化血红素分解代谢的限速酶,他可以氧化降解血红素,将其分解为一氧化碳、自由铁和胆绿素.血红素氧合酶-1(HO-1)是唯一可以被诱导的血红素氧合酶,近年来大量的研究发现HO-1具有抗炎、抗凋亡、抗增生反应等多种保护作用.HO-1不仅可以在机体生理状态下发挥作用,更为重要的是他可以在机体非正常状态包括应激状态下被诱导,被认为是在细胞受损时维持其氧化和抗氧化动态平衡的关键因素.本文就HO-1在器官移植研究领域的细胞保护作用作如下综述.  相似文献   
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