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51.
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   
52.
Peripheral deafferentation of the rodent olfactory bulb results in loss of dopamine content, tyrosine hydroxylase activity and immunocytochemical staining for tyrosine hydroxylase in juxtaglomerular dopamine neurons. Reinnervation of the bulb by afferent neurons results in the return of all parameters to control levels suggesting that the dopamine neurons did not degenerate but that the expression of tyrosine hydroxylase enzyme was transneuronally regulated in a static population of juxtaglomerular cells. To evaluate this possibility, we determined the activity and immunocytochemical localization of the second enzyme in the dopamine biosynthetic pathway, DOPA decar?ylase. At a time when tyrosine hydroxylase activity was reduced to 25% of control values, DOPA decar?ylase activity in the lesioned bulb was maintained at about 65% of that in the unlesioned bulb. Immunocytochemical staining with antibodies to both enzymes, performed sequentially in the same sections, demonstrated that in the unlesioned bulb tyrosine hydroxylase and DOPA decar?ylase are co-localized in the same population of juxtaglomerular neurons. Similar results were obtained in adjacent sections each stained with one of the two antibodies. In contrast, in the deafferented bulb, about three times as many neurons were stained with DOPA decar?ylase as with tyrosine hydroxylase antibodies. The DOPA decar?ylase activity measurements and immunocytochemistry argue for the continued presence, in the lesioned olfactory bulb, of a population of tyrosine hydroxylase deficient dopamine neurons.The data suggest that olfactory receptor cell innervation transneuronally regulates the expression of tyrosine hydroxylase by mechanisms separate from those controlling the levels of DOPA decar?ylase.  相似文献   
53.
应用显微分光光度计测定15例鼻咽癌19处癌旁病变的上皮细胞核DNA含量并与浸润癌相比较。中、重度异型增生上皮细胞核DI及超过2.5c细胞的百分数处于单纯增生+轻度异型增生与浸润癌之间,3组DI及超过2.5c细胞的百分数差异显著。中、重度异型增生以非整倍体为主,其细胞核DNA含量组方图相似于浸润癌。从细胞核DNA含量角度来看,中、重度异型增生是重要的癌前病变。  相似文献   
54.
A developmentally immature sleep pattern has been identified in infants with a recent history of an unexplained life-threatening episode of sleep apnoea who are considered at risk for SIDS. In these infants there is a persistence of Sleep Onset REM Periods (SOREMPS) after prolonged wakefulness when compared to controls matched for age, sex, birthweight and race. This sleep characteristic has not been previously reported.  相似文献   
55.
An immunohistochemical study was made of cathepsin-D protein expression in each of the three main types of uterine cervical carcinoma (squamous carcinoma, adenosquamous carcinoma and adenocarcinoma) with particular reference to lymph node status and prognosis. Of the 61 cases, 54.1% showed cytoplasmic staining in more than 2.5% of tumour cells counted. Cathepsin-D expression was significantly higher in adenocarcinoma (mean -3.128) than in squamous carcinoma and adenosquamous carcinoma (mean –3.709,P=0.047 using logit transformation). Cathepsin-D had no prognostic value in any of the three tumour types. No relationship was found between cathepsin-D staining and lymph node status and there was no advantage in adding cathepsin-D values to lymph node status. These results suggest that immunostaining for cathepsin-D protein expression is unlikely to be of use as a prognostic marker.  相似文献   
56.
基于线性调频信号的高帧率超声成像系统   总被引:5,自引:0,他引:5  
基于有限衍射波束的高帧率超声成像系统能实现快速成像,但由于仅通过一次发射事件成像,信噪比较低,本研究针对该问题提出一种改进方案。它采用合成孔径雷达中所使用的线性调频信号作为激励信号,在接收端则利用线性调频信号的脉冲压缩比等于信号的时间带宽积的特征,将接收信号通过匹配滤波器处理。结果表明该方案不仅能显著提高成像系统的信噪比,改善重构图像的质量,增加成像深度,而且不损失分辨率。  相似文献   
57.
Summary: The chromatographic analysis of hydrophilic copolymers is complicated due to the fact that in most cases aqueous eluents must be used. In aqueous eluents different polar and ionic effects may disturb the selective interactions between the macromolecules and the stationary phase making it impossible to separate such copolymers with regard to chemical composition. Therefore, 2D chromatography combining a separation according to composition with a separation according to molar mass has been applied mostly to polymers that are soluble in organic solvents. The present contribution describes experimental approaches to analyze such hydrophilic copolymers by 2D‐chromatography. For a model polymer system resulting from the copolymerization of methacrylic acid and a poly(ethylene glycol) macromonomer, it is shown that different analytical techniques including SEC, LC‐CC, MALDI‐TOF MS and 2D chromatography can be used to analyze the different parameters of molecular heterogeneity of such copolymers.

2D separation of poly(MPEG‐MM 2), 1st dimension: LC‐CC, 2nd dimension: SEC.  相似文献   

58.
Objective To study on adsorption effect of cadusafos and atropine sulfate by hemoperfusion.Method Hemoperfusions were performed for sheep blood samples with cadusafos and atropineby through imitated extracorporeal closed circulating perfusion apparatus.Residual cadusafos was determined by gas chromatography and residual atropine was determined by high performance liquid chromatography.Result Dose of adsorption agent was 0.5,1.0 and 1.5 g,respectively.Two hours after hemoperfusion with membrane coated activated charcoal,clearance rate of cadusafos in 3 groups all exceeded 90%.and clearance rate of atropine sulfate was 61.9%,84.9%,88.9%,respectively.One and a half hours after hemoperfusion with HA230 absorption resin,clearance rate of eadusafos in 3 groups all exceeded 90%,and clearance rate of atropine sulfate was 88.0%,97.2%,98.4%,respectively.Three hours after hemoperfusion with membrane coated activated charcoal,The concentration ratio of cadusafos and atropine sulfate in blood promoted to 10.1 times,and the ratio was 6.7 times after hemoperfusion with HA230 absorption resin.Conclusion It suggested that cadusafos were mostly removed from blood after 1.5~2.0hours hemoperfusion with membrane activated charcoal or HA230 absorption resin.The concentration ratio of cadusafos and atropine sulfate in blood will increased after hemoperfusion.  相似文献   
59.
Long-Evans hooded rats were tested for emotionality and observed by pairs in an open field for 6 consecutive days. Postoperative observations indicated that both emotionality and social cohesiveness were dramatically altered by ventromedial and anterolateral hypothalamic lesions. Tegmental, interpeduncular and habenular lesions were shown to have no effect on these behaviors. Alterations in behavior observed following hypothalamic ablations were related to septal and amygdaloid effects, and the possibility of separate projection systems for emotionality and social cohesiveness was discussed.  相似文献   
60.
Summary Experiments were performed on rats to determine whether primary afferents from the upper cervical region terminate directly on Spinothalamic and propriospinal neurones. The central terminations of primary afferents from the upper cervical region were identified by diffusely filling their axons with horseradish peroxidase. Spinothalamic neurones or propriospinal neurones were identified in the same experimental animals by using retrograde transport of wheat germ agglutinin conjugated to horseradish peroxidase. Approximately 3–11 % of Spinothalamic cells in laminae 4–6 of spinal segments C2–4 received apparent synaptic contacts from primary afferents on the soma or primary dendrites. Approximately 18–36% of propriospinal neurones with axons descending to lower thoracic or lumbar levels received apparent synaptic contacts on the soma or primary dendrites. These data provide anatomical evidence that Spinothalamic and long propriospinal neurones in the upper cervical cord are excited directly by primary afferents. The data also help to clarify the neural circuitry underlying somatic sensation and reflex movements evoked by neck receptors.  相似文献   
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