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排序方式: 共有1309条查询结果,搜索用时 15 毫秒
1.
巴戟天枯萎病对寄主显微构造及成分的影响   总被引:5,自引:3,他引:2  
枯萎病能显著影响巴戟天肉质根的显微构造,并显著影响巴戟天营养器官B,Mn等元素的转运以及根、茎的β-谷甾醇含量,使肉质根总糖含量下降5.42%~15.29%。  相似文献   
2.
大鼠下丘脑弓状核的形态计量研究   总被引:1,自引:1,他引:0  
为了探讨急性癫痫弓状核形态改变与可复性,我们采用光、电镜技术和形态计量方法对下丘脑弓状核进行了形态定量研究。结果显示:弓状核切面面积为317500±6460um2,神经元胞体和胞核的等效直径分别为12.94±0.34um和8.54±0.43um,暗细胞内线粒体、粗面内质网、高尔基复合体、溶酶体、游离核相体和分泌颗粒的面积分数分别是5.87±1.98%、3.53±0.25%、0.81±0.49%、2.13±0.42%、10.53±0.46%和0.86±0.35%,其面数密度(单位面积为30um2)分别为15.68±1.14um-2、21.29±3.52um-2、10.20±0.42um-2、5.62±067um-2、101.35±7.55um-2和5.22±0.77um-2.本文还对弓状核的形态结构、神经元类型及其功能进行了讨论。  相似文献   
3.
康廷国  高志 《中成药》1992,14(10):13-15
对定坤丹(蜜丸)进行了显微鉴定研究,将29种组成药物全部检出,对各组成药物的显微鉴别特征作了简明描述,并附显微特征图。  相似文献   
4.
The electron microscopic autoradiographic tracing method has been used to examine the morphology and postsynaptic relationships of five projections (retina, cortical area 17, superior colliculus (tectal), parabigeminal nucleus, and pretectum) to the dorsal lateral geniculate nucleus of the greater bush baby galago crassicaudatus. Retinal terminals have been examined in the contralaterally innervated layer of each of the three matched pairs [parvi-(X-cell), magno- (Y--cell), and koniocellular (small, W-cell)] of geniculate layers. These terminals are large and contain pale mitochondria and round vesicles (RLPs). RLPs are presynaptic to juxtasomatic regions of parvi-and magnocellular neurons. In contrast, RLPs innervate more distal regions of konicellular neurons. Labeled cortical, tectal, and parabigeminal terminals are relatively small and contain round vesicles na dark mitochondria. Cortical terminals in each of the three representative layers are presynaptic to small diameter dendrites. No convergence of cortical and retinal terminals has been seen in any layer. Labeled tectal and parabigminal terminals are found primarily in the koniocellular layers, but the latter are also seen in all other layers. Tectal and parabigeminal terminals have been observed converging with retinal terminals on dendrites of some koniocellular neurons. Labeled pretectogeniculate terminals contain densely packed pleomorphic vesicles, dark mitochondria, and a dark cytoplasmic matric. These terminals, which are present in each of the representative layers, are presynaptic to conventional dendrites and profiles containing loosely despersed pleomorphic vesicles and a pale cytoplasmic matrix. © 1994 Wiley-Liss, Inc.  相似文献   
5.
6.
Background Itraconazole is an orally active antifungal lipophilic drug with high affinity for sebum and keratinocytes. Aim The aim of the study was to investigate the routes of percutaneous egression and the sites of cutaneous action/storage of 3H-labelled itraconazole in an experimental animal model. Material and methods Hartley guinea pigs were dosed orally by gavage for 2 consecutive days at 10 mg/kg/day 3H-itraconazole dissolved in polyethylene glycol 200. At various time points after the second gavage, small full-thickness samples of dorsal skin were excised and processed using dry-apposing autoradiography. Results Our research revealed an accumulation of silver grains over the epidermis and its appendages (hair follicle and sebaceous gland), the dermal fat tissue and the hypodermal muscle tissue on tissue sections at 6, 24 and 48 h time intervals, whereas at the remaining time points (96, 168 and 336 h) the silver grain density was markedly decreased to background level. Discussion The present histological distribution data support the current method of oral treatment with itraconazole as the treatment schedule of choice to eradicate infective organisms residing in the deeper skin layers.  相似文献   
7.
本文解剖观察了30只手共150个手指的腱纽内动脉和神经。进入肌腱的动脉和神经都是手指两侧的指掌侧固有动脉和指掌侧固有神经的分支,它们穿过腱纤维鞘裂孔进入腱纽,然后再分支到屈指肌腱。动脉和神经在进入腱纽的起始处有脂肪团,可作为寻找腱纽内动脉与神经的标志。至拇指腱纽的动脉和神经是在第一指骨底至第一指骨头之间进入腱鞘,其它的指一般一个手指有四组动脉、两组神经分别进入每个手指的四型腱纽,而进入腱鞘的位置分别在:一指底,一指中间1/3与远侧1/3的交接处,二指底,二指头。其中Ⅱ、Ⅳ型的动脉有神经伴行。  相似文献   
8.
显微定量法测定中成药中猪牙皂的含量   总被引:2,自引:0,他引:2  
目的 :制定猪牙皂在脐风散与惊风散中的显微定量标准。方法 :用显微定量法 ,以猪牙皂特有的石细胞为显微特征物 ,对脐风散与惊风散中的猪牙皂进行测定。结果 :猪牙皂含量与每毫克特征数呈显著的线性正相关 ,回归方程为 y =61 .42 x -1 .1 0× 1 0 - 3(γ=1 .0 0 ,α=0 .0 5 )。结论 :显微定量法测定脐风散与惊风散中猪牙皂的含量是可行的 ,结果可靠  相似文献   
9.
Tranexamic acid has been advocated for patients with severe bleeding tendency due to thrombocytopenia not responding to platelet transfusions. Macroscopic haematuria is a well-known contraindication for its use in such patients. We present three clinical cases with microscopic haematuria, in whom tranexamic acid caused problems of clot formation in the urinary tract, indicating that microscopic haematuria should also be considered as a contraindication for tranexamic acid.  相似文献   
10.
BACKGROUND: We examined the incidence and natural history of simple renal cysts found by ultrasonography (US) in patients referred for asymptomatic microscopic hematuria. METHODS: Among the 906 patients aged 18-78 years, 743 patients who had undergone US were included in the present study. The natural history of simple renal cysts was investigated in 55 patients who underwent periodical US examinations for more than 3 years. RESULTS: The incidence of simple renal cysts was 4.3% for ages 29 years or younger, 15.3% for ages 30-39, 21.8% for ages 40-49, 23.3% for ages 50-59 and 32.6% for ages 60 years or older; thus the incidence increased in older age groups (P = 0.0005 for men, P = 0.0020 for women). Men tended to have a higher incidence than women. The degree of hematuria did not influence the incidence of renal cysts (P = 0.9044). The annual growth rate of the mean maximum diameter was 4.2% during a 3-year follow-up period in 55 patients and 5.1% during a 6-year follow-up in 31 patients. CONCLUSION: Since the diameter of a renal cyst may increase by 5% annually, the diameter of the cyst may increase by 1.6 times in 10 years. The scheduling of follow-up examinations depends on the size at the time of disclosure, the effects on calyceal systems, or the suspicion of a concurrent malignant disease. However, the most simple renal cysts may be followed-up at an interval of more than 10 years, once a diagnosis has been established.  相似文献   
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