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21.
Deoxycholic acid (DA) caused a dose-related release of histamine (HR) from mast cells of rat peritoneum (RPMC) and mucosal cells of guinea pig rectocolon (RCMC). In both cell populations, DA-induced HR was: (1) accompared by a parallel release of lactate dehydrogenase (LDH), (2) not affected by metabolic inhibitors, (3) dependent on time of incubation, temperature and pH, and affected by Ca++ concentration in RPMC but not in RCMC. DA-induced HR from RCMC may be involved in certain functional disorders of the colon.  相似文献   
22.
BACKGROUND: Masseteric muscle hypertrophy is an uncommon dition represented as a swelling of the masseter muscle. Recent reports have demonstrated the successful use of botulinum in the treatment of masseteric hypertrophy. OBJECTIVE: This study was a prospective trial to evaluate the effectiveness of botulinum toxin type A (Botox) in the treatment of masseteric muscle hypertrophy according to doses of 10, 20, and 30 U. MATERIALS AND METHODS: Twenty-two patients were referred to the dermatologic clinic for the management of masseteric muscle hypertrophy. Ultrasonographic measurements of the thickness of the masseter muscle were performed, and clinical photographs were taken before treatment and 1, 2, 3, 4, 6, and 9 months after the treatment. RESULTS. The median values of percentage reduction of muscle mass were 10.3%, 16.5%, 23.7%, 24.7%, 21.6%, 16.5% in the 10 U group; 11.9%, 18.8%, 24.8%, 27.7%, 26.7%, and 21.8% in the 20 U group; and 12.0%, 19.4%, 25.0%, 27.8%, 37.8%, and 24.1% in the 30 U group. CONCLUSION. The adequate dose of botulinum toxin type A for treatment of masseteric muscle hypertrophy should be above 20 U. The effect of botulinum toxin type A is maintained for at least 9 months as the treatment of masseteric muscle hypertrophy.  相似文献   
23.
The effects of lentinan on peripheral blood mononuclear cell (PBMC) expression of IL-2 receptor in patients with chronic hepatitis B in vitro and in vivo were studied. The expression percentage of IL-2 receptor in 44 patients with chronic hepatitis before treatment was 36.74 +/- 7.74, which was lower than healthy subjects, and was 48.92 +/- 3.79 after 2 months treatment of lentinan, which was approximated the normal control. PBMC from 30 patients with chronic hepatitis B were cultured in vitro with or without lentinan. The percentage of expression IL-2 receptor was 12.81 +/- 2.62 without lentinan and was 35.70 +/- 4.87 in the presence of lentinan. The concentration of lentinan stimulating expression of IL-2 receptor was between 0.2 to 200 g.ml-1. The results suggest that lentinan stimulates expression of IL-2 receptor on PBMC, which is associated with the therapeutic effectiveness of lentinan treatment.  相似文献   
24.
白内障超声乳化吸出及囊袋内人工晶体植入术   总被引:1,自引:0,他引:1  
为观察和评价超声乳化白内障吸出术的临床效果、特点、并发病及防治措施,对41 眼白内障施行超声乳化吸出术及小切口(6mm)囊袋内人工晶体植入术,并以同期的白内障患者41眼行现代囊外摘除及后房型人工晶体植入做对照。结果:术后6个月,视力≥1.0者占43.9%>0.8者占70.7≥0.5者占92.7%,均明显高于对照组(P<0.001),术后平均散光为1.04±0.81,1,低于对照组(P<0.01)。白内障超声乳化吸出并囊袋内人工晶体植入术的复明效果优于囊外摘除并后房型人工晶体植入术。  相似文献   
25.
脐血CD34~+细胞体外短期培养扩增研究   总被引:2,自引:0,他引:2       下载免费PDF全文
为寻找更有效的体外扩增脐血CD34 + 细胞的造血细胞因子组合 ,采集健康产妇脐带血 ,用免疫磁珠法分选CD34 + 细胞。采用SCF、FLT3 L、TPO和IL 34种具有早期作用的细胞因子的不同组合进行脐血CD34 + 细胞短期无血清液体培养 ,观察培养前后有核细胞、CD34 + 细胞、CD34 + /CD38- 细胞、CFU GEMM、CFU GM和BFU E数量的变化。结果在 3种不同的细胞因子组合中 ,同时应用SCF、FLT3 L、TPO和IL 34种细胞因子培养 7d的扩增效果最好。突出的发现是在这种条件下CD34 + /CD38- 细胞亚群达到平均 1 97.9倍的扩增效果。提示 :SCF、FLT3 L、TPO和IL 34种细胞因子是脐血CD34 + 细胞体外扩增理想的细胞因子组合  相似文献   
26.
556例遗传咨询病例细胞遗传学分析   总被引:1,自引:0,他引:1  
目的 :分析染色体异常与临床疾病的关系。方法 :应用细胞培养染色体分析技术对 5 5 6例遗传咨询病例进行细胞遗传学检查。结果 :发现 47例染色体结构或数目异常 ,占受检人数的 8.4% ,其中常染色体异常 39例 ,性染色体异常 8例。此外检出 46例 ,XY女性反转综合征 2例。结论 :反复自然流产和不孕不育夫妇及怀疑 Down综合征者应进行染色体检查  相似文献   
27.
OBJECTIVE: To evaluate the short-term therapeutic effect of percutaneous transluminal coronary angioplasty (PTCA) with stent implantation in the treatment of myocardial infarction with severe pump failure. METHODS: The clinical data of 73 patients receiving PTCA and stent implantation for myocardial infarction with severity pump failure were analyzed and grouped according the occurrence of complications, degree of the vascular lesions and the complexity of the surgical procedures. Preoperative and postoperative ventricular ejection fractions (LVEF) were compared in each case. RESULTS: The degree of vascular lesions and surgical complexity were not shown to relate to the occurrence of the complications. Except in cases complicated by chronic renal dysfunction, significant improvement was achieved in the patients 7 d after the operation (P<0.05), regardless of different degrees of vascular lesions and surgical complexity. CONCLUSION: PTCA with stent implantation is effective to improve the short-term cardiac function of patients with myocardial infarction and severe pump failure.  相似文献   
28.
本文观察了硝酸钚溶液经腹腔一次注入大鼠体内,不同时间后胸腺淋巴细胞超徽结构损伤效应与修复规律.早期可见淋巴细胞质膜及内膜系统的变化,以后出现核损伤,注后20天损伤最严重。以小淋巴细胞的损伤更明显。注后1月细胞损伤有所减轻,6个月基本恢复正常。  相似文献   
29.
OBJECTIVE: The aim of this study was to evaluate the usefulness of measurement of the angle between bilateral renal pelves on axial views in the prenatal ultrasonographic diagnosis of horseshoe kidney. METHODS: We retrospectively measured the renal pelvic angle in 19 fetuses with horseshoe and 20 fetuses with normal kidneys in the second and third trimesters. Renal pelvic angle was defined as the angle between the long axis of the renal pelves on the axial view of the abdomen. We compared the renal pelvic angles of horseshoe and normal kidneys with unpaired t-test. Taking 140 degrees as a cut-off value, we calculated the sensitivity, specificity and accuracy of pelvic angle measurement for the prenatal diagnosis of horseshoe kidney. RESULTS: The mean pelvic angles in the fetuses with horseshoe kidney were 116 degrees and 110 degrees in the second and third trimester, respectively. In the normal fetuses, the equivalent angles were 172 degrees and 161 degrees. The difference between the two groups was statistically significant (P < 0.01). Using 140 degrees as the discriminating criterion, the sensitivity, specificity and accuracy of renal pelvic angle measurement for the prenatal diagnosis of horseshoe kidney were all 100%. Fifteen of 19 fetuses with horseshoe kidney had no other abnormality. Four (21%) fetuses had severe complex abnormalities which were associated with trisomy 18 in three cases. CONCLUSION: Observation and measurement of the renal pelvic angle is a simple and useful method in the prenatal diagnosis of the horseshoe kidney.  相似文献   
30.
Use of bioactive cationic peptides as gene carriers is limited by instability of their DNA complexes in vivo and by the loss of their biological activity due to undesired interactions of their bioactive parts with the DNA. To overcome the two major limitations, biodegradable high-molecular-weight form of TAT peptide (POLYTAT) sensitive to cellular redox-potential gradients was synthesized in this study by oxidative polycondensation. Physicochemical and transfection properties of DNA polyplexes based on POLYTAT were investigated and compared with polyplexes based on TAT polymer prepared by in situ template-assisted polymerization. Physicochemical properties of TAT-based polyplexes were affected by the molecular weight and method of polymerization of the TAT peptide. All TAT-based DNA polyplexes exhibited reduced cytotoxicity when compared with control polyethylenimine (PEI) polyplexes. Polyplexes based on both high-molecular-weight TAT polypeptides exhibited increased transfection efficiency compared to control TAT peptide but lower than that of PEI polyplexes. The evidence shows that transfection activity of TAT-based polyplexes is strongly dependent on the presence of chloroquine and therefore suggests that TAT polyplexes are internalized by an endocytosis. Overall, high-molecular-weight reducible polycations based on bioactive peptides has the potential as versatile carriers of nucleic acids that display low cytotoxicity and can prove to be especially beneficial in cases that require surface presentation of membrane-active or cell-specific targeting peptides.  相似文献   
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