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51.
对60例输卵管结扎术后近段闭塞(间质部及峡部)妇女采用改良输卵管子宫角植入术,并对部分病例切除的近段输卵管标本进行病理形态学观察。病理检查发现:①输卵管慢性炎症;②输卵管子宫内膜异位症;③管腔内增生的纤维组织填塞。术后随访50例(83.33%),输卵管通畅46例(92%),宫内妊娠29例(58%),校正妊娠率为63.04%,宫外孕1例,表明宫角植入术用于此类结扎术后输卵管近段闭塞病例的复通有较好疗效。对此术式的关键点及术后宫内妊娠率与绝育年限、年龄、术后输卵管长度的关系作了分析。  相似文献   
52.
6 mandibles were radiographically examined bilaterally to visualise the mandibular canal. 5 imaging techniques were used: periapical radiography, panoramic radiography, hypocycloidal tomography, spiral tomography and computed tomography (CT). Panoramic radiographs were obtained with 2 different X-ray machines. The CT-examinations comprised direct images and standard reconstructions based on axial slices. The specimens were subsequently sectioned for contact radiography. The visibility of the mandibular canal was estimated by 3 observers at special reference points on all radiographs and classified as clearly visible, questionable visibility or not visible. The contact radiographs served as the "gold standard". The inter-observer and the intra-observer agreement were assessed by calculating the overall agreement and the x value. Direct coronal computed tomography, as well as spiral and hypocycloidal tomography, gave better visualisation of the mandibular canal than periapical and panoramic radiography.  相似文献   
53.
BackgroundPatellofemoral joint cartilage defects are difficult to treat due to their unique thickness and topography.PurposeTo report the postoperative outcomes of patients age 21 and younger treated with particulated juvenile allograft cartilage (PJAC) for full-thickness cartilaginous defects of the patellofemoral joint. The primary aim was to report surgical outcomes and complication rates, as well as return to sport activity. A secondary aim was to provide objective scores of defect restoration by magnetic resonance imaging (MRI) assessment.MethodsA retrospective review of all PJAC cases conducted between 2012 and 2019 at a single tertiary care urban musculoskeletal institution was conducted. Patients 21 years old or younger with minimum clinical follow up of 1 year and postoperative MRI at a minimum of 6 months were included. Cartilage restoration by MRI was independently assessed using the International Cartilage Repair Society’s (ICRS) standardized system.ResultsThirty four patients, 36 knees, were included, with mean age 16.1 ± 3.1 years old. Return to sport rate among patients who participated in a sport preoperatively was 100%. On independent MRI assessment, two thirds of defects achieved an overall grade of normal or nearly normal, while 28 patients (78%) had majority defect fill. Primary graft failure occurred in two cases and one patient experienced a surgical complication.ConclusionRestoration of patellofemoral chondral defects in young patients with particulated juvenile allograft results in satisfactory short-term outcomes and postoperative MRI appearance, along with high rates of return to sport and low rate of complications and graft failure.What is known about the subject: Patellofemoral joint cartilage defects are difficult to treat due to their unique thickness and topography. Several cartilage restoration techniques are available, but these rarely achieve the same mechanical properties as native hyaline cartilage. PJAC is a cell-based technique that has demonstrated promise since its introduction in 2007.What this study adds to existing knowledge: This series of patients adds the largest single cohort of pediatric and adolescent patients who receive PJAC for defects of the patellofemoral joint. Surgeons treating patients in this age group should be aware of every technique, and their respective outcomes.  相似文献   
54.
A novel sutureless vascular connecting system, an assembly with a delivery rod, an introducing sheath, and a connecting device, was developed for easy implantation of small-caliber vascular grafts less than 2 mm in internal diameter. A microporous stainless tube (length 2 mm, external diameter 1.6 mm, wall thickness 65 µm, pore diameter 400 µm, pore-to-pore distance 500 µm) was designed to serve as a connecting device. The feasibility of the system was tested using two types of preliminary animal experiments. One animal model consisted of graft implantation into the rat abdominal aorta (1.5 mm in diameter). The connecting device was inserted into the proximal and distal ends of the aorta through the introducing sheath by pushing the delivery rod with the connecting device placed over it. Subsequently, the aortic segments were inserted into both ends of model grafts made of segmented polyurethane (1.8 mm in internal diameter) and were fixed with banding silk threads from the exterior. The procedure was completed within 20 min without requiring specialized microsurgery techniques. Blood leakage and obstruction did not occur. The second model consisted of an end-to-end anastomosis between rabbit common carotid arteries (2 mm in diameter), which was performed within several minutes of blood flow interruption. Scanning electron microscopy demonstrated that the luminal surface of the device was fully covered with endothelial cells (ECs) after 1 week as a result of transluminal ingrowth of native ECs through the micropores in the device. This endothelialization may prevent early thrombus-induced occlusion. This simple and “easy-to-learn” technique will promote the development of small-caliber arterial grafts, and furthermore, it may have potential for clinical application.  相似文献   
55.
BACKGROUND: Withholding gonadotrophin administration and postponing HCG injection, termed coasting, has been suggested as a treatment modality in cases of impending ovarian hyperstimulation syndrome (OHSS). It presents an opportunity to reduce the risk of OHSS and salvage the treatment, without apparent compromise to outcome. However, the duration of the coasting period, which would maintain the advantage without reducing conception rate, has not been fully established. In this retrospective study, we attempted to define the optimal interval of coasting in patients at risk of developing OHSS. METHODS: Patients were grouped according to the number of days elapsed between cessation of gonadotrophins and administration of HCG. Overall, out of 207 patients (mean age 30.76 +/- 0.33 years) coasting lasted 1 day in 39 cycles (18.8%), 2 days in 61 cycles (29.4%), 3 days in 49 cycles (23.6%) and > or = 4 days in the remaining 58 cycles (28.5%). RESULTS: There was no difference between the groups in patients' age, serum estradiol concentrations at the time of HCG administration, oocyte maturity, fertilization and embryo cleavage rates. However, patients in whom coasting lasted > or = 4 days had significantly reduced implantation (10.5%) and pregnancy (26.7%) rates compared with patients with a shorter coasting interval (ranges 18.4-27.9 and 41-55.7% respectively; P < 0.05). CONCLUSION: Coasting for >3 days appears to reduce implantation and pregnancy rates while in-vitro oocyte and embryo quality do not appear to be affected. We suggest that in patients who need coasting for >3 days, cryopreservation of embryos should be considered.  相似文献   
56.
温勇  刘斌 《解剖科学进展》1998,4(4):346-349
应用FITC标记的L3T4及Ly2单克隆抗体,及流式细胞计细胞分选,对小鼠妊娠期间脾脏T淋巴细胞亚群进行检测。结果表明,妊娠早期小鼠脾脏CD8+淋巴细胞比例减少,在着床时尤为明显。提示脾脏T淋巴细胞数量和功能变化,参与维持正常妊娠,尤其是参与着床。  相似文献   
57.
目的:通过研究细胞因子对FN表达的调节,探讨FN在围着床期子宫内膜表达的调节机理。方法:给孕早期小鼠注射不同的细胞因子,收集子宫内膜。分别用Immuno-blot法及RT-PCR法测定子宫内膜FN蛋白和nRNA的水平。结果:LIF低、高剂量组的FNmRNA和蛋白水平都比对照组高,统计分析差异有显著性(P<0.05,P<0.01),IL-1和IL-1ra各组FN水平与对照组比无显著差异。结论:LIF在转录和转录后水平上调早期子宫内膜FN的表达,LIF参与着床与调节粘附分子的表达有关。IL-1系统则不影响子宫内膜FN的合成。  相似文献   
58.
氧离子注入增强人工关节软骨材料-UHMWPE的耐磨性   总被引:10,自引:0,他引:10  
用高能离子注入机对超高分子量聚乙烯 (U HMWPE)进行了 O+注入改性 ,注入能量为 4 5 0 ke V和 10 0ke V,剂量分别为 1× 10 1 5/cm2 ,5× 10 1 5/cm2和 1× 10 1 6 /cm2。以 Si3N4 球为上销样 ,UHMWPE为下盘样组成摩擦副 ,在销盘摩擦试验机上评价它们在干摩擦和蒸馏水润滑条件下的磨损性能。结果表明 ,几种注入工艺均增强了UHMWPE的耐磨性 ,但提高了其摩擦系数 ,其中以能量为 4 5 0 Ke V,剂量为 5× 10 1 5/cm2的注入样品耐磨性最好。未注入 U HMWPE的磨损主要表现为黏着、塑性变形和犁沟 ,注入 U HMWPE的磨损主要为表面硬化层疲劳裂纹的萌生、扩展、剥落及磨粒磨损  相似文献   
59.
BACKGROUND: In this prospective randomized blinded clinical trial, we examined gene expression profiles of the human endometrium during the early and mid-luteal phases of the natural cycle. METHODS: An endometrial biopsy was performed on day 16 (LH +3) or on day 21 (LH +8), followed by RNA extraction and microarray analysis using an Affymetrix HG-U95A microchip. Data analysis was carried out using pairwise multiple group comparison with the significance analysis of microarrays (SAM) software. RESULTS: With a false discovery rate of 0, the analysis revealed that 107 genes were significantly and differently expressed (> or =2-fold) during the early versus the mid-luteal phase of the cycle. Forty-five of these genes have not been previously linked to endometrial receptivity. Validation of the microarray data was accomplished using semiquantitative RT-PCR. We demonstrated the presence of estrogen and progesterone response elements (ERE and PRE) by analysis of the 5'-flanking regions of a subset of differentially regulated genes. CONCLUSIONS: Using a strict bioinformatics approach of microarray data, we demonstrated significant changes in candidate genes during the transition of the early to the mid-luteal phase of the human endometrium that may have functional significance for the opening and maintenance of the window of implantation.  相似文献   
60.
BACKGROUND: Integrins are thought to play a vital role in implantation. Three integrins in particular (alpha(4)beta(1), alpha(v)beta(3) and alpha(1)beta(1)) are all present during the implantation window. Defects in their expression have been linked to tubal disease, unexplained infertility and endometriosis. Hence, a reduced endometrial integrin expression would be expected in women attending for IVF due to these causes of infertility when compared with those with male factor infertility attending for ICSI. METHODS: Women attending for IVF (n = 25) and ICSI (n = 25) treatment were recruited, and timed endometrial biopsies were taken during the 'implantation window' (cycle day 20-24). A group of fertile women (n = 15) attending for sterilization was used as controls. RESULTS: There was no significant difference in integrin expression between patients undergoing IVF or ICSI. Neither did these groups differ from the control group. CONCLUSIONS: The endometrium in patients undergoing ICSI treatment is sometimes thought to be more receptive, as the infertility might be due to a male factor. This study shows that there is no significant difference in integrin expression between patients attending for IVF or ICSI and the control group. These data add to the increasing uncertainty about the clinical value of assessing the endometrium with only one marker, in this case integrins.  相似文献   
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