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51.
核医学影像设备的发展与临床应用 总被引:3,自引:3,他引:0
γ相机和SPECT只能进行常规单光子显像,PET和双探头SPECT符合显像系统既能进行单光子显像,又能进行正电子符合显像,PET/CT系统的出现不仅提供高质量的衰减校正图像,保证了正电子显像校正数据的可靠性,而且能进行同机图像融合,提高了影像定位诊断的准确性。本文简要介绍了核医学影像设备发展历程,PET和PET/CT的原理以及在临床的应用。 相似文献
52.
The purpose of this investigation was to evaluate the effect on healing of fast and slow absorbable Tisseel in combination with periodontal flap surgery. Mucoperiosteal flaps were raised on the buccal aspect of maxillary premolars and mandibular premolars and first molars in 4 beagle dogs. The underlying buccal, interproximal and inter-radicular bone was then removed to a level of approximately 5 mm apically to the original bone crest and half way into the interdental spaces and bifurcations. The exposed root surfaces were curetted in order to remove the periodontal ligament tissue, and a notch was made in the root surface at the base of the defects. On the control teeth, the flaps were sutured immediately after creation of the defects, while on the test teeth, a layer of fast (group I) or slow (group II) absorbable Tisseel was applied between the curetted roots and the subsurface of the flaps prior to suturing. Postoperatively, the teeth were brushed 2 x weekly. The dogs were sacrificed after 4 months. Histological analysis revealed that the amounts of new attachment and bone regrowth were similar in the test and control groups, although the results tended to be most favorable for the group of teeth treated with fast absorbable Tisseel (Group I). 相似文献
53.
目的探讨黄芪丹参复方成分提高胎盘血供的分子机制,为临床有效防治胎盘血供不足所致妊娠并发症提供思路。方法提取分离黄芪、丹参复方成分,运用NOS(一氧化氮合酶)阻滞剂L-精氨酸甲酯(L—NAME)建立一氧化氮合成阻滞大鼠模型,ELISA法检测妊娠18d大鼠血浆IL-1、IL-10水平。以及胎盘超微形态学变化,大鼠血压、尿蛋白变化,以及仔鼠重、肝重、脑重、胎盘重等。结果一氧化氮合成阻滞模型组IL-1含量明显高于空白组(P〈0.01),经黄芪丹参注射液治疗后,血浆IL-1水平比模型组降低(P〈0.05);模型组IL-10含量较空白组低(P〈0.01),中药组血浆IL-10水平高于模型组(P〈0.05);胎盘形态学、血压、尿蛋白以及仔重、仔肝重、脑重等均有显著差异(P〈0.05,P〈0.01)。结论黄芪丹参复方成分可能对妊娠早期母-胎界面免疫平衡具有调控作用,通过促进局部生理抑制性免疫反应增强和杀伤、排斥免疫反应减弱,从而有利于母胎循环构建,维持胎盘血液供应。 相似文献
54.
THE PHYSIOLOGY OF PRE-ECLAMPSIA 总被引:2,自引:0,他引:2
Mark A. Brown 《Clinical and experimental pharmacology & physiology》1995,22(11):781-791
1. Pre-eclampsia is a multisystem disorder of human pregnancy with a genetic predisposition. It occurs more commonly in first pregnancies and primarily affects maternal renal, cerebral, hepatic and clotting functions while elevating blood pressure. The foetus is affected through placental insufficiency arising from abnormal ‘placentation’, that is, failure of adequate trophoblast invasion of maternal vasculature, and possibly from abnormal autacoid production. 2. Pre-eclampsia is caused by the placenta; delivery of the placenta is the only known cure. Its manifestations are considered secondary to organ hypoperfusion which arises as a result of vasoconstriction, intravascular coagulation and reduced maternal blood volume. 3. Current hypotheses propose that pre-eclampsia is due to widespread maternal endothelial cell damage, perhaps secondary to a cytotoxic factor released by the placenta. This hypothesis has gained wide acceptance, but scientific evidence is lacking. 4. Defining the abnormal balance of vasoactive factors in pre-eclampsia has proved a difficult task. There is enhanced pressor reactivity to infused angiotensin 11 (AII) despite reduced plasma concentrations of AII, renin and aldosterone. Prostacylclin production appears reduced, and the balance of thromboxane/prostacyclin favours vasoconstriction and platelet aggregation. There is no convincing evidence for enhanced endothelin or reduced nitric oxide production. Plasma concentrations of atrial natriuretic peptide are paradoxically elevated in the face of plasma volume contraction. An intriguing observation, which remains unexplained, is why some vascular beds are affected predominantly in one patient (eg. hepatic ischaemia) while another has a similar degree of hypertension but involvement of a different organ system (eg. renal insufficiency yet normal liver function). 5. Volume homeostasis is disturbed with redistribution of intravascular volume to the interstitial fluid space due to increased capillary permeability and in some cases reduced plasma oncotic pressure. This redistribution is not always clinically apparent as peripheral oedema. Whether this change in volume is compensated for by venoconstriction and maintenance of adequate cardiac output is undetermined. 6. Improved understanding of the pathophysiology of pre-eclampsia is necessary to allow better clinical management of this serious disorder. 相似文献
55.
Objective: To investigate a possible role of apoptosis in the pathophysiologic mechanisms of PIH ( pregnancy-induced hypertension syndrome). Methods: In this study, placental samples were obtained from 16 uncomplicated third-trimester pregnancies and from 16 cases of PIH. We used light microscopy, electron microscopy to identify apoptosis. Light microscopy was used to quantify their incidence of apoptosis. Electron microscopy was used to confirm the occurrence of apoptosis. Results: Apoptosis has been conclusively demonstrated within human third-trimester placental tissue. Medians and interquartile ranges of normal placenta (n = 16) was 0. 12% (0. 08% -0. 19% ) ; Medians and interquartile ranges of PIH group (n = 16) was 0. 37% (0. 15% -0.49% ). Compared to normal placentas, the incidence of apoptosis was higher in placentas from gestations complicated by PIH ( P < 0. 05 , T'-test). Conclusion: Placental apoptosis increases significantly in PIH, and it may play a role in the pathophysiologic mechanisms 相似文献
56.
中西医结合治疗慢性盆腔炎100例疗效观察 总被引:2,自引:1,他引:1
目的:采用中西医结合治疗慢性盆腔炎,减少复发,提高治愈率。方法:对我院门诊患者100例采用胎盘组织液肌注,金钢藤胶囊口服,并用我院自制中药妇炎肠疗液灌肠。结果:临床显效40例,有效56例,无效4例,总有效率96%。结论:中西医结合治疗慢性盆腔炎疗效满意,是目前治疗慢性盆腔炎的最好方法。 相似文献
57.
STEEN M. JENSEN ADRIAN PIETERSEN XU CHEN 《Pacing and clinical electrophysiology : PACE》1998,21(2):476-477
Routinely the active can ICD is placed in the left side pectoral position, which theoretically gives optimal conditions for a low defibrillation threshold. Some patients, bowever, demand a right pectoral position, which possibly could result in a bigger defibrillation threshold. A right pectoral position was used in 3 of 85 active can ICDs implanted in our institution from 1994. the DFT was 12 J in two and 18 f in one patient. Thus, right pectoral implantation is feasible and offers an alternative approach in selected patients. 相似文献
58.
一氧化氮与胚胎异常发育的相关性研究 总被引:3,自引:0,他引:3
为了解开一氧化氮(NO)是否与畸胎发生有关这一谜团和进一步阐明砷致畸作用机理,本实验应用诱生型NO合成酶(iNOS)组织化学、扫描电镜(SEM)及体内致畸试验等方法研究了砷对小鼠卵黄囊胎盘(YSP)和胚胎发育的影响。结果表明YSP细胞iNOS表达与砷浓度之间存在明显的剂量—反应关系(P<0.05);SEM观察可见YSP内皮层和间皮层细胞受损;光镜下可见YSP变小、萎缩和微血管分化不良;随着染毒剂量的升高,畸胎率和死胎率亦逐步增加,最高分别达到56.8%和24.7%;畸胎的主要表现是神经管未闭,心包积液和体位异常等。研究结果率先提示过量NO与畸胎发生及致畸机理关系密切;推荐在致畸研究中iNOS可作为一种有效的生物标志物。 相似文献
59.
E. Alsat PhD J. Guibourdenche PhD D. Luton MD F. Frankenne PhD D. Evain-Brion MD PhD 《American journal of obstetrics and gynecology》1997,177(6):1526-1534
Placental growth hormone is the product of the GH-V gene specifically expressed in the syncytiotrophoblast layer of the human placenta. Placental growth hormone differs from pituitary growth hormone by 13 amino acids. It has high somatogenic and low lactogenic activities. Assays by specific monoclonal antibodies reveal that in the maternal circulation from 15 to 20 weeks up to term placental growth hormone gradually replaces pituitary growth hormone, which becomes undetectable. It is secreted by the placenta in a nonpulsatile manner. This continuous secretion appears to have important implications for physiologic adjustment to gestation and especially in the control of maternal insulin-like growth factor-I levels. Placental growth hormone secretion is inhibited by glucose in vitro and in vivo and is significantly decreased in the maternal circulation in pregnancies with intrauterine growth restriction. Placental growth hormone does not appear to have a direct effect on fetal growth because this hormone is not detectable in the fetal circulation. However, the physiologic role might also include a direct influence on placental development through an autocrine or paracrine mechanism, as suggested by the presence of specific growth hormone receptors in this tissue.(Am J Obstet Gynecol 1997;177:1526-34.) 相似文献
60.
A prospective and controlled study of training after surgery for lumbar disc herniation (LDH). The objective was to determine
the effect of early neuromuscular customized training after LDH surgery. No consensus exists on the type and timing of physical
rehabilitation after LDH surgery. Patients aged 15–50 years, disc prolapse at L4–L5 or L5–S1. Before surgery, at 6 weeks,
4, and 12 months postoperatively, the following evaluations were performed: low back pain and leg pain estimated on a visual
analog scale, disability according to the Roland–Morris questionnaire (RMQ) and disability rating index (DRI). Clinical examination,
including the SLR test, was performed using a single blind method. Consumption of analgesics was registered. Twenty-five patients
started neuromuscular customized training 2 weeks after surgery (early training group=ETG). Thirty-one patients formed a control
group (CG) and started traditional training after 6 weeks. There was no significant difference in pain and disability between
the two training groups before surgery. Median preoperative leg pain was 63 mm in ETG and 70 mm in the CG. Preoperative median
disability according to RMQ was 14 in the ETG and 14.5 in the CG. Disability according to DRI (33/56 patients) was 5.3 in
the ETG vs. 4.6 in the CG. At 6 weeks, 4 months, and 12 months, pain was significantly reduced in both groups, to the same
extent. Disability scores were lower in the ETG at all follow-ups, and after 12 months, the difference was significant (RMQ
P=.034, DRI P=.015). The results of the present study show early neuromuscular customized training to have a superior effect on disability,
with a significant difference compared to traditional training at a follow-up 12 months after surgery. No adverse effects
of the early training were seen. A prospective, randomized study with a larger patient sample is warranted to ultimately demonstrate
that early training as described is beneficial for patients undergoing LDH surgery. 相似文献