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71.
自1992年3月至1994年5月,对中原地区4个省20多个县(市)近200个单位33555名20~75岁的已婚妇女,进行妇科疾病发生情况与年龄、职业、文化、月经、孕产等五种因素关系的调查分析。在33555名妇女中,患病者22370人,总患病率为66.67%,查出妇科疾病42种,计76974例次。结果证明:以25~35岁年龄组发病率最高,其中以内生殖器炎症为主;职业以经商者发病率高,特别是性病患者高于其他职业者二倍以上;文化程度以小学、初中者发病率高,尤其宫颈炎更明显;月经情况:随着经前期紧张综合征的加重,更年期综合征发病率增高;孕产次数越多,患病率越高。本次调查未发现宫颈癌,进一步证明我国对妇女保健工作的关心和重视。 相似文献
72.
宫颈粘液过氧化物酶在月经周期中的变化规律 总被引:3,自引:1,他引:2
本文对29例月经周期正常妇女的宫颈粘液过氧化物酶进行了30个周期的研究。在月经周期不同时间测定宫颈粘液过氧化物酶(CMPx)活性及血清促黄体生成素(LH)、雌二醇(E_2)和孕酮(P)。结果表明:在排卵前三天酶活性明显下降,至排卵后一天开始上升。卵泡期,酶活性与E_2呈负相关(r=-0.67);黄体期,酶活性与P呈正相关(r=0.79)。本研究提示:1.CMPx在排卵周期具有特定的变化规律,其变化受体内激素水平影响,可作为预告排卵的指标。2.如简化测定方法,可为自然避孕提供新途径。 相似文献
73.
Antithrombotic effect of beta,beta''-monochloromethylene diadenosine 5'',5"''-P1,P4-tetraphosphate. 下载免费PDF全文
B K Kim P Zamecnik G Taylor M J Guo G M Blackburn 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(22):11056-11058
The feasibility of using beta,beta'-monochloromethylene diadenosine 5',5"'-P1,P4-tetraphosphate (AppCHCl-ppA) as an antithrombotic agent was studied in a rabbit intracarotid cannula thrombosis model previously shown to be sensitive to antiplatelet agents. This analogue, having a P-C-P bridge in place of a P-O-P internucleoside linkage, has been found resistant to phosphodiesterase activity. Rabbits were infused with the dinucleotide at a dose of 50 mg per kg over a 2-hr period, at a controlled rate by pump. A 1-cm length of polyethylene cannula (1 mm i.d.) was tied into the carotid artery. Animals were stable under general anesthesia during the entire period of the experiment. In the control group, 16 of 20 animals formed clots, an incidence of 80%, whereas in the test animals, 6 of the 20 formed clots (30% incidence, P < 0.05). After preincubation of whole blood with 50 microM AppCHClppA at 37 degrees C for up to 3 hr, a consistent suppression of ADP-induced platelet aggregation was observed. The present study suggests that AppCHClppA may be useful as an antithrombotic agent in certain clinical situations, such as hemodialysis, arteriovenous shunts, and introduction of artificial heart valves. It may also possibly prevent extension of recent clots. The toxicity and metabolism of AppCHClppA have, however, yet to be explored. 相似文献
74.
75.
Preparation and characterization of porous beta-tricalcium phosphate/collagen composites with an integrated structure 总被引:11,自引:0,他引:11
Porous beta-tricalcium phosphate (TCP)/collagen composites with different beta-TCP/collagen weight ratio were prepared. The influences of the preparation conditions on the microstructure of porous composite and the joint status of beta-TCP particles with collagen fibrils were characterized by X-ray diffractometer, scanning electron microscopy and transmission electron microscopy. The results showed: (1) an acid treatment could effectively disassemble collagen fibrils; (2) in the resulting porous composites, beta-TCP particles homogenously existed on the skeleton of the collagen fibril network and bonded tightly to both the fibrils and themselves. The tight bonding formation could be due to the reaction between Ca ions in the particles and carboxyl groups in collagen polypeptide chains and due to the reprecipitation of partially dissolved beta-TCP during synthesis. The tight bonding between beta-TCP particles and collagen fibrils in the composites demonstrated an integrated structure, which was reproducible when beta-TCP/collagen ratio ranged from 2 to 4. Such integrated structure would make significant contributions in reliably tailoring properties of the porous composites by varying beta-TCP content. In addition, the porous composites had large porosity (approximately 95%) and appropriate pore size (approximately 100 microm), showed no negative impact in cytotoxicity assay and complete bone tissue regeneration after 12 weeks in animal test. 相似文献
76.
Kazuhiko Yasuml Rong-Jun Guo Hiroyuki Hanai Hajime Arai Eizo Kaneko Hiroyuki Konno Selichi Takenoshita Koichi Hagiwara Haruhiko Sugimura 《Pathology international》1998,48(2):134-137
A new mutation in the serine-threonine klnase domain of the transforming growth factor β type II receptor (TGFpRII) was found in a case of diffuse, B cell non-Hodgkin's lymphoma of the stomach. A mfssense mutation (ACA to GCA, Thr to Ala) was detected In exon 5, and a wild type allele was also present. This Is the first naturally occurring mutation in the klnase domain of this gene identified in human primary lymphoma. The replication error at three loci was negative, and the poly A tract of exon 3, which is frequently a target of mismatch repair genes, was intact. Malignant lymphoma of B cell origin in the stomach Is an addition to an expanding catalogue of tumors with TGFβRII alterations, and the biological sequelae of the change in the functional domain and the clinical characteristics of the patient in this study are intriguing. 相似文献
77.
78.
缺血性脑血管疾病是一个非常复杂的病理生理过程 ,是多种机制共同作用的结果。本文从针刺对实验性脑缺血在脑组织形态学改变、血液流变学、脑微循环等方面的研究进展作一综述。 相似文献
79.
应用免疫细胞化学(ICC)和放射免疫分析(RIA)方法观察了大鼠4、25Gy~(60)Coγ射线照射后24,48和,72h空肠亮脑啡肽(L-ENK)样免疫反应性神经的分布和L-ENK含量的变化。结果:4Gy照射后24h以及25Gy照射后24,48和72h光镜下见空肠L-ENK样免疫反应性神经的分布密度稍有增加,4Gy照射后24h以及25Gy照射后24,48和72h空肠L-ENK含量分别为29.81±0.84pg/mg,34.96±4.38pg/mg,40.71±3.62pg/mg和38.93±2.31pg/mg,与正常对照组(18.26±1.95pg/mg)相比明显升高(P<9.01)。 相似文献
80.
Yin C Ying L Zhang PC Zhuo RX Kang ET Leong KW Mao HQ 《Journal of biomedical materials research. Part A》2003,67(4):1093-1104
Galactosylated surface is an attractive substrate for hepatocyte culture because of the specific interaction between the galactose ligand and the asialoglycoprotein receptor on hepatocytes. In this study, we described a scheme to achieve high density of immobilized galactose ligands on polyethylene terephthalate (PET) surface by first surface-grafting polyacrylic acid on plasma-pretreated PET film under UV irradiation, followed by conjugation of a galactose derivative (1-O-(6'-aminohexyl)-D-galactopyranoside) to the grafted polyacrylic acid chains. A high galactose density of 513 nmol/cm(2) on the PET surface was used in this study to investigate the behavior of cultured hepatocyte. This engineered substrate showed high affinity to fluorescein isothiocyanate-lectin binding. Primary rat hepatocytes, when seeded at a density of 2 x 10(5) cells/cm(2), attached to the galactosylated PET substrate at a similar efficiency compared with collagen-coated substrate. The hepatocytes spontaneously formed aggregates 1 day after cell seeding and showed better maintenance of albumin secretion and urea synthesis functions than those cultured on collagen-coated surface. 相似文献