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排序方式: 共有1110条查询结果,搜索用时 31 毫秒
1.
During lower extremity amputation, the objective is to provide a functional residual limb that permits maximum patient mobility and independence. Preservation of length of the fore part of the foot using salvageable tissue from the amputated part in young patients prevents equines deformity and revision of amputation to a higher level. This can be achieved using tissue available from the amputated part. The spare part concept in reconstructive surgery should be integrated into the trauma algorithm to avoid additional donor site morbidity. Reported here is a young adult patient with crush injuries to both feet, which resulted in amputations. A fasciocutaneous flap raised from one extremity was used to facilitate transmetatarsal amputation stump length preservation of the other extremity.  相似文献   
2.
急性中风中脏腑证型与垂体-肾上腺轴激素关系的研究   总被引:6,自引:0,他引:6  
目的 :探讨急性中风中脏腑证型与垂体—肾上腺轴激素的促肾上腺皮质激素 (ACTH)、皮质醇 (CS)的关系。方法 :对 78例中脏腑患者进行辨证分型 ,同时利用放射免疫分析 (RIA)法测定血中 ACTH、CS含量 ,按证型分为四组 ,对比不同证型间 ACTH、CS的水平 ,并与健康人组 (60例 )作对照。结果 :ACTH、CS含量水平比较 :1四种证型的 ACTH、CS均比正常健康人组高 (P <0 .0 0 1 ) ;2四种证型间比较有明显差异 (P<0 .0 1 ) ,从高到低为 :痰热内闭心窍证 >风火上扰清窍证 >痰湿蒙塞心神证 >元气败脱、心神散乱证。结论 :ACTH、CS含量水平可作为判别中脏腑不同证型间的微观指标  相似文献   
3.
对四种同季不同产地采集的“三颗针”不同部位的四种生物碱进行了含量测定和分析,为该类药材的质量研究、生药采收、药厂选投料及开发应用等提供了科学依据。同时对该类资源的可持续利用也具有积极意义。  相似文献   
4.
肩肱皮瓣修复颈部瘢痕挛缩畸形疗效分析   总被引:1,自引:0,他引:1  
目的:探讨颈部瘢痕挛缩畸形的有效外科治疗手段。方法:采用瘢痕广泛松解、双侧或单侧肩肱皮瓣转移,同时用全厚皮片移植修复供瓣区创面。结果:本组21例中,17例手术一次性完成,4例分两次完成。不但改善了患者的上肢功能,还可进一步改善患者颈部的活动度。结论:瘢痕广泛松解、双侧或单侧肩肱皮瓣转移,同时用全厚皮片移植修复供瓣区创面是颈部瘢痕挛缩畸形的有效外科治疗手段。  相似文献   
5.
Summary In urethane anesthetized rats neuronal responses of the visual part of nucleus reticularis thalami (vTR) to light were compared with those during pairing light as a conditioned stimulus (CS) with the electrical stimulation of the rat's tail (US). The intensity of the US was adjusted to the minimum required to evoke a slight freezing behavior in the awake rat. The firing rate of most vTR neurons decreased in the period between light and US application (P < 0.01). Significant response modulations to light were observed in 39% of the units, in most of them they persisted over an extinction period of 15 min. In addition, neurons which were predominantly inhibited by conditioning sometimes changed from regular spiking to a burst pattern. The results support the hypothesis that conditioning related facilitation of geniculate neurons observed in previous experiments can be explained at least partly by disinhibition of geniculate units from vTR.  相似文献   
6.
[目的] 探索甘草地上部分活性部位对小鼠的急性毒性及大鼠的长期毒性,评价其安全性,为合理开发利用甘草地上部分资源以及临床应用提供可靠的理论依据。[方法] 甘草地上部分活性部位33.2 g/kg灌胃给予昆明种小鼠,24 h内两次(间隔5 h)经口灌胃给予受试物,持续观察14 d内小鼠的急性毒性反应;SD大鼠随机分为对照组和甘草地上部分低、中、高剂量组,按8.3、16.6、33.2 g/kg剂量连续灌胃甘草地上部分活性部位90 d,观察大鼠的一般状况,并分别于给药后45、90 d进行血液学指标检测与血清生化指标检测,给药后90 d进行大体解剖及病理学检查,观察甘草地上部分活性部位的长期毒性反应。[结果] 急性毒性实验中小鼠的一般状态、饮食、分泌物、排便未见异常,无小鼠死亡,肉眼尸检心、肝、脾等主要脏器组织未见明显异常;长期毒性实验中,各组大鼠与对照组比较,一般状况、血液学及血清生化指标未见明显差异;病理检查未见主要脏器组织形态学改变。[结论] 甘草地上部分活性部位无急性毒性和长期毒性,在治疗剂量范围内用药安全性高。  相似文献   
7.
Male wild (Cavia aperea) and domestic (C. porcellus) guinea pigs were tested in two-bottle choice tests for preferences between glucose solutions of different concentrations and de-ionized water. Wild males showed significant preferences for concentrations between 0.025 and 0.4 M glucose while domestic males preferred only the 0.2 M glucose solution to de-ionized water. C. aperea males also consumed significantly greater volumes of liquid per kg body wt.34 during the glucose tests than did the C. porcellus males. These comparative results contrast sharply with those obtained by other authors with wild and domestic Norway rats.  相似文献   
8.
M Ikeda  T Tanami  M Matsushita 《Neuroscience》1984,12(4):1243-1260
The distribution of cells of origin of ascending and descending internuclear connections in the trigeminal sensory nuclei was studied by the retrograde horseradish peroxidase technique in the cat. The termination of collaterals of these ascending axons was also studied by the anterograde transport of horseradish peroxidase. Following injections of horseradish peroxidase into the ventral part of the principal sensory nucleus and the adjacent reticular formation many small neurons were labeled ipsilaterally in the whole area of the caudal portion of the nucleus interpolaris and in laminae III and IV of the nucleus caudalis. Labeled neurons were also found in laminae I and V. Injections limited to either nucleus oralis, the ventral part of the principal sensory nucleus and the medial parabrachial nucleus labeled similar types of neurons in the above regions with a topographic relationship; neurons in the dorsal part of the nuclei caudalis and interpolaris project, dorsally, to rostral portions of the trigeminal sensory nuclei while those in the ventral part of the nuclei caudalis and interpolaris project ventrally. Anterograde labeling of axons arising from the nucleus caudalis demonstrates that the axons ascend in the intranuclear bundles and the adjacent reticular formation, and give off collaterals to the nuclei interpolaris and oralis, and the ventral part of the principal sensory nucleus. Injections limited to the nucleus caudalis labeled small neurons in the rostral portion of the nucleus oralis and the caudal portion of the nucleus interpolaris. The present study suggests that these ascending and descending internuclear connections of the trigeminal sensory nuclei may modulate transmission of afferent inputs to various projection sites, such as thalamus, superior colliculus, cerebellum and spinal cord.  相似文献   
9.
A rare case of an alveolar soft part sarcoma of the uterine cervix in an 8 year old girl is presented. The patient was admitted because of genital bleeding lasting for 7 months. A polypoid tumor, 2times1.5 cm in diameter, was found in her external uterine os and was surgically resected. Microscopically, the tumor consisted of a uniform sheet of tumor cells in the cytoplasm which contained granules and which were stained with periodic acid-Schiff, both before and after the diastase digestion. Alveolar arrangement of the tumor cells was manifested with reticulin silver impregnation. Dense, membrane bound granules were evident at an ultrastructural level in the cytoplasm of the tumor cells. An immunohistochemical examination demonstrated a positive reaction for anti-desmin, anti-myoglobin, anti-HHF35 and anti-neuron specific enolase in the cytoplasm.  相似文献   
10.
The role of several motor and intralaminar thalamic nuclei in the regulation of dopamine release from terminals and dendrites of the nigrostriatal dopaminergic neurons was investigated in halothane-anaesthetized cats. For this purpose, the effects of the unilateral electrical stimulation of various thalamic nuclei on the release of newly synthesized [3H]dopamine were simultaneously determined in both substantiae nigrae and caudate nuclei using the push-pull cannula method. The electrical stimulation of the motor nuclei was the only one to induce asymmetric changes in the four structures since [3H]dopamine release was enhanced in the ipsilateral caudate nucleus and reduced in the contralateral structure while opposite responses were observed in the corresponding substantiae nigrae. A reduction of [3H]dopamine release occurred in the four structures or only in the contralateral substantia nigra and caudate nucleus following the stimulation of the parafascicularis nucleus and the adjacent posterior part of the nucleus centrum medianum or of the nucleus centralis lateralis and the adjacent paralaminar part of the nucleus medialis dorsalis, respectively. The stimulation of the anterior part of the nucleus centrum medianum, which in contrast to other thalamic nuclei examined, receives few nigral inputs, selectively enhanced [3H]dopamine release in the contralateral substantia nigra. No significant changes in [3H]dopamine release were seen either in the substantiae nigrae or in the caudate nuclei following the stimulation of midline thalamic nuclei. These results indicate that the motor and intralaminar thalamic nuclei exert multiple and selective influences on the release of dopamine from terminals and/or dendrites of the dopaminergic neurons. They also further support a role of thalamic nuclei in the transfer of information from one substantia nigra to the contralateral dopaminergic neurons. The possible involvement of connections between paired thalamic nuclei was underlined by the observations of evoked potentials in contralateral homologous nuclei following unilateral stimulation of motor, or some intralaminar, nuclei. The present report provides new insights on the mechanisms contributing to the reciprocal and/or bilateral regulations of nigrostriatal dopaminergic pathways.  相似文献   
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