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956.
As a synthetic polypeptide water-soluble poly(l-glutamic acid) (PLGA) was designed to fabricate scaffolds for cartilage tissue engineering. Chitosan (CHI) has been employed as a physical cross-linking component in the construction of scaffolds. PLGA/CHI scaffolds act as sponges with a swelling ratio of 760 ± 45% (mass%), showing promising biocompatibility and biodegradation. Autologous adipose-derived stem cells (ASCs) were expanded and seeded on PLGA/CHI scaffolds, ASC/scaffold constructs were then subjected to chondrogenic induction in vitro for 2 weeks. The results showed that PLGA/CHI scaffolds could effectively support ASC adherence, proliferation and chondrogenic differentiation. The ASCs/scaffold constructs were then transplanted to repair full thickness articular cartilage defects (4 mm in diameter, to the depth of subchondral bone) created in rabbit femur trochlea. Histological observations found that articular defects were covered with newly formed cartilage 6 weeks post-implantation. After 12 weeks the regenerated cartilage had integrated well with the surrounding native cartilage and subchondral bone. Toluidine blue and immunohistochemical staining confirmed similar accumulation of glycosaminoglycans and type II collagen in engineered cartilage as in native cartilage 12 weeks post-implantation. The result was further supported by quantitative analysis of extracellular matrix deposition. The compressive modulus of the engineered cartilage increased significantly from 30% of that of normal cartilage at 6 weeks to 83% at 12 weeks. Cyto-nanoindentation also showed analogous biomechanical behavior of the engineered cartilage to that of native cartilage. The results of the present study thus demonstrate the potentiality of PLGA/CHI scaffolds in cartilage tissue engineering.  相似文献   
957.
The purpose of this study was to identify the spectrum of cytological diagnoses and evaluate the diagnostic effectiveness of fine needle aspiration cytology (FNA) in patients less than 20 years old. The subjects were selected by retrospectively reviewing records from 1999 to 2009. Selected patients less than 20 years old underwent FNA. Cytological and histological slides of samples from the subjects were reviewed. Our study included a total of 909 subjects with a mean age of 14.6 years. The majority of the FNA samples were taken from lymph nodes (n = 448, 49.3%), with the remaining aspirates obtained from the thyroid gland (n = 247, 27.2%), soft tissues of head and neck masses (n = 106, 11.7%), salivary glands (n = 75, 8.3%), breasts (n = 18, 1.9%), skins (n = 9, 1.0%) and soft tissues of extremity (n = 6, 0.7%). The majority (87.6%, n = 796) of the FNA samples were categorized as ‘benign’, with the remaining designated as ‘atypical lesion’ (n = 18, 2.0%), ‘malignant’ (n = 24, 2.6%), or ‘inadequate specimen’ (n = 71, 7.8%). FNA accuracy was 92% for diagnosing cancer. Specificity and sensitivity were 99% and 63%, respectively. Our study first revealed that FNA has a high specificity for diagnosing cancer in various anatomical locations in young patients and can be confidently used as an effective tool for diagnosing malignancies in young individuals with a clinically suspicious lesion.  相似文献   
958.
目的:研究成人大骨节病髋关节病变的影像学特点,并与骨关节炎患者进行对比。方法:对四川省壤塘县112例(224髋)确诊为成人大骨节病的患者进行髋关节摄片,观察髋关节髋臼侧、股骨侧有无影像学改变,测量髋关节Sharp角、CE角、髋臼指数、头转子间距离、头颈指数和颈干角,并将测量结果与我院40例(80髋)原发性骨关节炎患者进行对比分析。结果:224髋中有22髋(9.8%)出现髋部异常改变,主要表现为髋臼软骨下骨硬化或囊变、股骨头形态不规则伴密度异常、颈干角变小。112例患者Sharp角平均37.92°、CE角平均30.26°、髋臼指数平均43.86、头转子间距离平均1.69cm、头颈指数平均1.80、颈干角平均121.8°。与骨关节炎患者相比,大骨节病组患者颈干角较小,其组间差异有统计学意义(P〈0.05),但均在正常范围内;其余测量指标两组比较均无统计学差异。结论:成人大骨节病部分患者髋关节在影像学方面具有异常改变,主要表现为髋臼软骨下骨硬化或囊变、股骨头形态不规则伴密度异常、颈干角变小。上述影像学改变与骨关节炎患者相比无明显特异性。  相似文献   
959.
This is a pilot study analysing association of chemokine gene polymorphisms (CXCL1, rs3117604; CXCL2, rs3806792; CCL2, rs2857656 and rs3760396; CCL5, rs2107538) in Korean patients with ischemic stroke (IS) (= 120) and age‐matched controls (= 267). The CXCL1 gene and particularly T allele of rs3117604 was associated with IS.  相似文献   
960.

Background/Aims

Quantification of the hepatitis B surface antigen (HBsAg) is increasingly used to determine the treatment response in patients with chronic hepatitis B (CHB). However, there are limited data about the clinical implications of Quantification of HBsAg long-term nucleoside analogue treatment for CHB. We investigated the clinical correlation between HBsAg level and clinical course in patients with CHB who are treated long-term with nucleoside analogues.

Methods

Patients with CHB who started lamivudine or entecavir monotherapy before June 2007 were enrolled. HBsAg was quantified at baseline, at 6 months, and at 1, 2, 3, 4, and 5 years of treatment. We compared data between the groups according to the presence or absence of a virological response (VR) and resistance.

Results

Forty-eight patients were analyzed. There was no definite reduction in HBsAg level during the early period of treatment; differences in HBsAg levels between baseline and each time point were significant only at 5 years (P=0.028). In a subgroup analysis, this difference was significant only in non-resistant patients at 5 years (P=0.041).

Conclusions

There was no definite decrease in the HBsAg level during the early period of nucleoside analogue treatment, with long-term treatment being required to observe a significant reduction.  相似文献   
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