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1.
本文报告了不同剂量X线所致Leydig细胞对hCG反应性的变化。幼年雄性大鼠睾丸的Leydig细胞经预培养24小时后,分别接受25,50,75,100,250mGy小剂量的X线照射(剂量率为12.5mGy/分)以及0.5,1.0,2.0,4.0,8.0Gy大剂量X线照射(剂量率0.51Gy/分)。然后加入浓度为0.025或0.05i.u./ml的hCG,继续培养48小时,观察Leydig细胞对hCG反应性的变化。结果表明,小剂量辐射在25,50mGy组引起Leydig细胞对0.05i.u./ml hCG的反应性增高,而在各小剂量组对0.025i.u./ml hCG的反应性无明显变化。大剂量辐射Leydig细胞在各剂量组对0.025和0.05i.u/ml hCG的反应性均降低,此种降低有照射剂量依赖性。对上述变化的可能机制进行了讨论。  相似文献   

2.
小鼠^60Co—γ射线照射后空肠组织中NO和cGMP含量变化   总被引:1,自引:0,他引:1  
目的和方法:选用BALB/c小鼠,采用一氧化氮荧光分光光度法和放射免疫测定法,对不同剂量60Co-γ射线(8Gy、12Gy、14Gy)照射后的小鼠和8Gy照射后不同时间(分别为24h、48h、72h)小鼠空肠组织中NO-2和cGMP含量进行了测定。结果:8Gyγ射线全身照射后,小鼠空肠组织中NO-2含量增加,照后48h含量最高,cGMP含量在照后24h最高,48h降至接近对照水平,在48h处,cGMP含量与照射剂量呈依赖性正相关。  相似文献   

3.
本实验采用图象分析系统(TAS)对~(60)C_0-γ射线8Gy全身一次照射后1、3、6、9、12天小鼠腹腔巨噬细胞内酸性磷酸酶(AcPase),三磷酸腺苷酶(ATPase)和脱氧核糖核酸(DNA)的含量进行定量观察。发现照射后巨噬细胞内AcPase、ATPase和DNA含量均下降,AcPase和ATPase含量在照后第6天下降明显,DNA含量在照后第3天下降最严重,以后均有程度不回的恢复。  相似文献   

4.
本实验共分二部分进行。第一部分,观察柴胡注射液解热效应,第二部分,观察柴胡注射液解热时对脑脊液cAMP含量变化的影响。用家兔内生致热原复制发热模型,剂量(1×10~6 cells/ml)0.5ml/kg。目前认为:cAMP是一种重要的中枢性发热介质,脑脊液中cAMP含量与发热效应呈正相关。本研究结果表明,柴胡注射液(250mg/kg)对内生致热原性发热有明显抑制作用;同时,脑脊液中cAMP含量也明显低于发热对照组。作者推论:柴胡注射液可能通过某些环节减少体温调节中枢神经元cAMP合成和释放,从而抑制发热效应。  相似文献   

5.
目的:探讨20 Gyγ射线不同分割模式头部照射对小鼠学习记忆的影响.方法:48只成年雄性C57BL/6小鼠随机分为对照组(control)、20 Gy单次照射组(20 Gy)、大分割照射组(5 Gy×4 d)和常规分割照射组(2 Gy×10 d),各照射组小鼠均头部接受γ射线照射,总剂量为20 Gy.照后4周采用Mor...  相似文献   

6.
目的:探讨60Co-γ射线(Gy)全脑照射后对小鼠血脑屏障通透性和室管膜下区神经干细胞增殖的影响。方法:112只健康小鼠随机分成0 Gy组(对照组),5 Gy照射组(小剂量照射组),15 Gy照射组(中等剂量照射组)和30 Gy照射组(大剂量照射组),每组28只。各组随机取出7只分别于照射后1周和4周测定各组小鼠脑组织伊文思蓝的含量,7只观察室管膜下区的BrdU+细胞形态和数量。结果:(1)照射后1周,15 Gy组和30Gy组脑组织伊文思蓝含量明显升高(P<0.05),室管膜下区的BrdU+细胞数明显降低(P<0.05);(2)照射后4周,15 Gy剂量照射组脑组织伊文思蓝含量和室管膜下区的BrdU+细胞数均恢复到对照组水平(P>0.05),而30Gy剂量照射组脑组织伊文思蓝含量仍明显升高(P<0.05),BrdU+细胞数也未见恢复(P<0.05)。结论:全脑照射后血脑屏障破坏可能对室管膜下区的细胞增殖有进一步抑制作用。  相似文献   

7.
宫颈癌调强放疗和三维适形放疗剂量对比研究   总被引:5,自引:0,他引:5  
目的:研究宫颈癌调强放疗(IMRT)和三维适形放疗(3D-CRT)时靶区及其周围正常组织受照剂量的差异.材料方法:用拓能公司生产的WiMRT三维适形调强放疗计划系统分别进行6~9个照射角度的3D-CRT和IMRT计划设计,肿瘤量45Gy,计算出正常组织和靶区的剂量—体积直方图以及所需照射的总跳数.用Siemens生产的Primart电子直线加速器(X射线能量6MV,MLC叶片29对)实施放疗计划,测量出10 cm×10cm射野外漏射线和散射线剂量率,估算放疗时正常组织所受辐射剂量随距离的变化关系.结果:照射野数和照射角度一致,IMRT时膀胱、直肠、阴道所受平均剂量分别只有3D-CRT时的19.5%(29.3/150.3)、64.5%(538.0/833.0)和61.0%(1553.6/2546.3),靶区平均受照剂量略高于3D-CRT.IMRT病人正常组织所受散射线和漏射线剂量约为3D-CRT病人的1.5倍.结论:宫颈癌IMRT剂量分布优于3D-CRT.  相似文献   

8.
本研究用静脉注射内毒素复制家兔双相热模型,观察双相热各期颈动脉血浆和脑脊液cAMP含量的变化及其与体温变化的关系,结果如下:1.内毒素非热限剂量一次静脉注射引起典型双相热。脑脊液cAMP含量在两个热相高峰期相应出现两个上升波,间歇期体温下降时,脑脊液cAMP含量相应降低,退热后恢复正常。血浆cAMP含量仅在第一热相增高。2.相关检验表明,脑脊液cAMP含量与体温变化呈显著正相关。血浆cAMP含量仅在第一热相与脑脊液cAMP含量相关。以上结果与内生致热原双相热相似,提示内毒素可能主要通过内生致热原以某种方式影响体温调节中枢cAMP的变化,导致双相热型的出现  相似文献   

9.
家兔侧脑室内注射纯化内生致冷原(endogenous cryogen,EC)引起直肠温度下降和耳皮肤温度上升,其反应与静脉注射的情况相似,但直肠温度降低更加迅速,所用剂量仅为静脉注射达到同样效应时的1/80。静脉注射EC降温反应过程中,体温下降至最低点时脑脊液cAMP浓度显著下降,而cGMP浓度没有显著改变,血浆cAMP和cGMP浓度均显著升高;体温回升至正常水平时脑脊液、血浆cAMP和cGMP浓度均与对照组无显著差异。本实验结果提示:(1)EC的主要作用部位可能是中枢神经系统;(2)cAMP可能参与EC降温反应的中枢机制。  相似文献   

10.
目的:通过X-射线体外全身照射BALB/c小鼠建立小鼠辐射损伤模型,检测放射线对小鼠脾组织、单核巨噬细胞及T、B淋巴细胞损伤的剂量范围,探索放射线剂量与组织损伤程度之间的量效关系。方法:采用9种不同剂量的X-射线体外全身照射BALB/c小鼠,于照射后1d、60d、120d取腹腔细胞做大吞噬实验;分离脾细胞,MTT法检测T细胞增殖活性,同时取脾脏组织切片、HE染色,检测组织损伤程度;照射后120d取小鼠脾细胞用流式细胞仪检测T、B细胞数量百分比。结果:不同剂量X-射线照射的小鼠其大吞噬细胞的吞噬指数及T细胞的增殖指数之间均存在差异,且与放射剂量呈负相关性。FCM检测结果显示0.1Gy及以上剂量组与正常对照组相比较,小鼠T、B淋巴细胞数量减少(P<0.05)。0.25Gy和0.5Gy组T、B淋巴细胞数量明显高于除0.05Gy以外的其余各照射组,但是仍低于正常组(P<0.05)。脾组织切片显示,照射后1d 0.1Gy以上照射组脾脏炎性细胞浸润;60d后,4.0Gy和8.0Gy组脾脏明显萎缩、巨噬细胞增生、瘤样变,其余组损伤不明显;120d后8.0Gy组脾脏萎缩、红白髓分界不清,白髓损伤尤为严重,其余组不明显。结论:0.1Gy以上X-射线体外全身照射可引起小鼠免疫功能及组织损伤,且损伤程度与放射性强度呈剂量依赖性。  相似文献   

11.
分子成像能以非侵入性的方式重现活体细胞的生理功能和生物学过程,提高疾病的早期和特异性诊断水平。纳米颗粒/材料具有物理性质可控性高、易于表面修饰、血液循环时间长和可功能化等优点,在疾病诊断与治疗中显示出巨大潜力。但如何阐明纳米材料多功能间的内在联系、解决其代谢及安全性等关键机制难题、实现纳米颗粒/材料多功能性到临床多功能...  相似文献   

12.
Circulating monocytes comprise functionally distinct regular (CD14bright+) and mature (CD141low+) cells. Cell surface receptors were determined by three colour flow cytometry in 8 healthy control subjects. Compared to regular monocytes, mature monocytes had lower levels of the high affinity Fcy receptor 1 (CD64), complement receptor 3 (CDllb), CD45RO and higher levels for HLA-DR, LFA-1 (CD11a/CD18), interleukin-2 receptor (CD25), CD45RA and the Fc receptor 3 (CD16). Both regular and mature monocytes were measured before and up to three hours after four different types of exercise (Ex) in endurance trained athletes (n=9-16). Immediately after anaerobic exercise of I min with a maximal lactate concentration (lamax) of I2.3 (SD I.4) mmol · l–1 and exhaustive exercise of 24 (SD 8) min with a maximal lactate concentration (lamax) of 7.4 (SD 2.6) mmol· l–1 mature monocytes increased more than regular monocytes. Exhaustive endurance exercise of 87 (SD 21) min [lamax 3.7 (SD I.0)] led to a similar increase of regular and mature monocytes. 15–33 min after a 100km run regular monocytes increased significantly, whereas mature monocytes decreased. Up to three hours after the end of all exercises mature monocytes fell below pre-exercise values. In conclusion, duration and intensity of exercise alter distinct maturation stages of monocytes differently. It is probable that the avidity of adhesion molecules like LFA-1 to their endothelial ligands is increased to enable the firm attachment to the endothelium.  相似文献   

13.

OBJECTIVES:

Declines in cognition and mobility are frequently observed in the elderly, and it has been suggested that the appearance of gait disorders in older individuals may constitute a marker of cognitive decline that precedes significant findings in functional performance screening tests. This study sought to evaluate the relationship between functional capacities and gait and balance in an elderly community monitored by the Preventive and Integrated Care Unit of the Hospital Adventista Silvestre in Rio de Janeiro, RJ, Brazil.

METHODS:

Elderly individuals (193 females and 90 males) were submitted to a broad geriatric evaluation, which included the following tests: 1) a performance-oriented mobility assessment (POMA) to evaluate gait; 2) a mini-mental state examination (MMSE); 3) the use of Katz and Lawton scales to assess functional capacity; 4) the application of the geriatric depression scale (GDS); and 5) a mini-nutritional assessment (MNA) scale.

RESULTS:

Reductions in MMSE, Katz and Lawton scores were associated with reductions in POMA scores, and we also observed that significant reductions in POMA scores were present in persons for whom the MMSE and Katz scores did not clearly indicate cognitive dysfunction. We also demonstrated that a decline in the scores obtained with the GDS and MNA scales was associated with a decline in the POMA scores.

CONCLUSIONS:

Considering that significant alterations in the POMA scores were observed prior to the identification of significant alterations in cognitive capacity using either the MMSE or the Katz systems, a prospective study seems warranted to assess the predictive capacity of POMA scores regarding the associated decline in functional capacity.  相似文献   

14.
Context: GnRH immunity can reduce the expression of pituitary GnRH levels, and cause the changes in reproductive behaviors. It is unclear whether triptorelin (TRI) and cetrorelix (CET) immunity influences uterine development and expression of follicle-stimulating hormone receptor (FSHR), luteinizing hormone receptor (LHR), and estradiol receptor 1 (ERS1) in the uterus.

Objective: The study investigated the effects of active immunity of GnRH agonist and antagonist on uterine development, microstructures, expression of hormone receptors mRNAs, and proteins in uteri.

Materials and methods: One hundred and five mice were assigned into CET, TRI, and control groups (CG). Mice in CET-1, CET-2, and CET-3 (n?=?15) were subcutaneously injected with 10, 20, and 40?μg CET antigens for seven days, respectively. Mice in TRI-1, TRI-2, and TRI-3 were injected with 10, 20, and 40?μg TRI antigens for seven days, respectively. The qPCR and Western blot were implemented to determine expressions of ESR1, LHR and FSHR mRNAs, and proteins.

Results: Compared with CG, the uterine weights of CET-1, CET-2, and CET-3 increased by 42.86, 62.86, and 10.00% on day 35 (p?p?p?p?p?Conclusions: CET immunity promoted the uterine development, improved EET and UWT, and also promoted the expressions of ESR1 and FSHR protein levels. It lessened the LHR protein levels. TRI immunity blocked EET and UWT, inhibited uterine growth and development. The efficacy of CET immunity was more obvious than TRI.  相似文献   

15.
16.
国际韧带和肌腱研讨会(The International Symposium on Ligaments and Tendons,ISI&T)于2000年在美国佛罗里达州奥兰多市首次召开。研讨会的宗旨是引起对韧带和肌腱研究的重视,并为生物工程师、生物学家、临床医师提供一个可以分享、评论、讨论韧带和肌腱最新研究成果的论坛。从2000年起,国际韧带和肌腱研讨会已经开展了15届;每届研讨会上涌现了大量令人振奋的关于当前韧带和肌腱研究热点和未来挑战的讨论。多年来,韧带和肌腱领域内的研究数量大幅增加,研究质量不断提升。为纪念《医用生物力学》杂志创刊30周年,本文总结过去30年里韧带和肌腱研究的主要进展,包括组织力学、力学生物学、损伤与治愈机制、组织修复和再生。  相似文献   

17.
Cytochemical reactions of blood leucocytes and thrombocytes from six species of fish, rainbow trout (Onchorhynchus mykiss), coho salmon (Onchorhynchus kisutch), white sturgeon (Acipenser transmontanus), goldfish (Carassius auratus), striped bass (Morone saxatulis), and channel catfish (Ictalurus punctatus) were determined. Because the staining reactions were generally similar to the reactions found in mammalian leucocytes with similar morphological features, it is reasonable to classify fish leucocytes using the same terminology as is used for mammalian leucocytes. However, in some species leucocytes with features similar to mammalian eosinophils or basophils were not found. In goldfish leucocytes were found that had segmented nuclei and unstained, moderately refractile cytoplasmic granules. These cells were classified as segmented, granular leucocytes. Although these cells do not appear similar to any mammalian or avian leucocyte, the pattern of positive cytoplasmic alkaline phosphatase staining and negative granular staining is similar to that of equine eosinophils.  相似文献   

18.
对113例男性乳腺发育症进行临床病理分析。同时检测其中30例乳腺组织中雌激素受体和孕激素受体分布情况,结果发现两者阳性率分别为80.0%和83.33%。结合文献讨论了男性乳腺发育症的发生与高血清激素浓度及乳腺组织高受体水平的关系。  相似文献   

19.
20.
Phaeochromocytoma and paraganglioma (PHEO/PGL) are rare tumours with an estimated annual incidence of 3 per million. Advances in molecular understanding have led to the recognition that at least 30–40% arise in the setting of hereditary disease. Germline mutations in the succinate dehydrogenase genes SDHA, SDHB, SDHC, SDHD and SDHAF2 are the most prevalent of the more than 19 hereditary genetic abnormalities which have been reported. It is therefore recommended that, depending on local resources and availability, at least some degree of genetic testing should be offered to all PHEO/PGL patients, including those with clinically sporadic disease. It is now accepted that that all PHEO/PGL have some metastatic potential; therefore, concepts of benign and malignant PHEO/PGL have no meaning and have been replaced by a risk stratification approach. Although there is broad acceptance that certain features, including high proliferative activity, invasive growth, increased cellularity, large tumour nests and comedonecrosis, are associated with an increased risk of metastasis, it remains difficult to predict the clinical behaviour of individual tumours and no single risk stratification scheme is endorsed or in widespread use. In this review, we provide an update on advances in the pathology and genetics of PHEO/PGL with an emphasis on the changes introduced in the WHO 2017 classification of endocrine neoplasia relevant to practising surgical pathologists.  相似文献   

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