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81.
82.
为研究长蛸神经系统结构及神经调控机制,通过解剖学和石蜡组织切片技术对长蛸的脑部结构进行观察。结果显示,以食道为参照,根据所处位置将脑分为3部分:食道上神经团、食道下神经团以及位于食道上下神经团两侧的视叶区。食道上神经团包含垂直叶、上额叶、下额叶、前基底叶和后基底叶,食道下神经团包含腕叶、足叶、巨细胞叶、色素细胞叶、内脏叶、外套内脏叶和血管舒缩叶,视叶区包含视神经、视叶、视腺、嗅叶、脑脚叶和视神经束。采用石蜡组织切片、光镜和透射电镜技术对视腺进行显微和超显微结构观察,结果发现视腺外有一层结缔组织包裹,位于视神经束区上,与嗅叶和脑脚叶相邻;内部可观察到大量分泌细胞,细胞核较大,直径范围为4~8μm;分泌细胞含有丰富的粗面内质网、高尔基体及高尔基体分泌的分泌小泡与大泡。研究表明,长蛸视腺结构特征与曼氏无针乌贼和真蛸的高度相似。  相似文献   
83.
For the transmission pressure 27.5 kV of the railroad AC contact network, and the non parallel (on earth) arbitrary plane for the wire wearing surface, the optic fiber was used to isolate the high voltage and to transmit the measurement signal. A remote grating type adaptive automatic machinery transducer was used to detect the AC contact network wire wearing surface with about seven meters from the ground. Based on this method, a system was designed and calibrated, achieving measurement of wire rubbing with high voltage. The actual measurements indicate that the method and the system satisfy the demand of the measurement of contact network wire wearing. The method is significant to the geometric sense measurement of the high voltage charged body.  相似文献   
84.
 【目的】探究鸡肠Remak神经(intestinal nerve of Remak,INR)的神经元和过路节超微结构,为进一步阐明INR的生理功能提供理论基础。【方法】应用透射电镜技术观察鸡肠INR元与过路节的超微结构。【结果】INR有大量体积巨大的神经元和少量小强荧光细胞分布。神经元胞体周围有零散的卫星细胞围绕,但不能形成完整被囊,可见卫星细胞与神经元胞体之间形成突触样联系。神经元周围基膜不明显,神经元胞体表面常直接与周围细胞间质接触。细胞核圆而表面平滑,染色质松散清亮,核内可见棒状小体的特殊结构。核仁明显,结构和组成典型。胞质内分布着丰富的微管、发达的粗面内质网和高尔基复合体,粗面内质网池常有扩张膨大。可见中央有孔的致密颗粒分布于核周质,可能为肽类递质分泌颗粒。核糖体除了附着于粗面内质网表面外,还有大量游离核糖体分布于胞质中。线粒体形态多样,并有致密化现象。肠INR被膜下分布着少量成群的小强荧光细胞,其胞质和胞核的电子密度较高,细胞之间有不对称的突触联系。根据突触小泡的不同,INR内分布着4种过路节,它们与周围结构形成不同的突触联系。【结论】INR神经元具有旺盛合成和分泌功能的超微结构特征,而过路节的组成和联系显示出INR支配活动的多样化和复杂性。  相似文献   
85.
土地储备规模预测研究——以长春净月经济开发区为例   总被引:2,自引:2,他引:0  
运用BP神经网络模型和灰色马尔柯夫模型对长春净月经济开发区土地储备规模进行了预测,确定了规划期内土地储备的合理规模:2010年为966~1159 hm2,2015年为963~1156 hm2,2020年为680~815 hm2。  相似文献   
86.
Understanding the normal course and optimizing visualization of the canine peripheral nerves of the lumbar plexus, in particular the sciatic and the femoral nerves, is essential when interpreting images of patients with suspected peripheral neuropathies such as inflammatory or neoplastic conditions. The purpose of this prospective, anatomic study was to describe the magnetic resonance imaging (MRI) anatomy of the normal canine femoral and sciatic nerves and to define the sequences in which the nerves are best depicted. A preliminary postmortem cadaver study was performed to determine optimal sequences and imaging protocol. In a second step the optimized technique was implemented on 10 healthy Beagle dogs, included in the study. The applied protocol included the following sequences: T1‐weighted, T2‐weighted, T2‐Spectral Attenuated Inversion Recovery, T1‐weighted postcontrast and T1‐Spectral Presaturated Inversion Recovery postcontrast. All sequences had satisfactory signal‐to‐noise ratio and contrast resolution in all patients. The sciatic and femoral nerves were seen in all images. They were symmetric and of homogeneous signal intensity, being iso‐ to mildly hyperintense to muscle on T2‐weighted, mildly hyperintense in T2‐Spectral Attenuated Inversion Recovery, and iso‐ to mildly hypointense in T1‐weighted images. No evidence of contrast enhancement in T1‐weighted and T1‐Spectral Presaturated Inversion Recovery postcontrast sequences was observed. The anatomic landmarks helpful to identify the course of the femoral and sciatic nerves are described in detail. This study may be used as an anatomical reference, depicting the normal canine femoral and sciatic nerves at 3 Tesla MRI.  相似文献   
87.
A 15‐year‐old, neutered male, Shih Tzu cross developed progressive corneal stromal thickening and vascularization of the right eye, and 5 months later, of the left eye. Both eyes became blind due to extensive corneal opacification and were enucleated. Light microscopic examination revealed a diffuse corneal infiltrate of neoplastic mesenchymal cells, and immunohistochemistry revealed diffuse cytoplasmic vimentin immunoreactivity and variable cytoplasmic and nuclear immunoreactivity for S100 in the neoplastic cells. Transmission electron microscopy revealed desmosomes between contiguous cells, thread‐like cytoplasmic processes coated with basement membrane, extracellular bundles of collagen, and axonal degeneration consistent with features of a nerve sheath neoplasm. This is the first report of primary, bilateral corneal nerve sheath sarcoma in a canine.  相似文献   
88.

Objective

To assess the efficacy of psoas compartment and sacral plexus block for pelvic limb amputation in dogs.

Study design

Prospective clinical study.

Animals

A total of 16 dogs aged 8 ± 3 years and weighing 35 ± 14 kg (mean ± standard deviation).

Methods

Dogs were administered morphine (0.5 mg kg?1) and atropine (0.02 mg kg?1); anesthesia was induced with propofol and maintained with isoflurane. Regional blocks were performed before surgery in eight dogs with bupivacaine (2.2 mg kg?1) and eight dogs were administered an equivalent volume of saline. The lumbar plexus within the psoas compartment was identified using electrolocation lateral to the lumbar vertebrae at the fourth–fifth, fifth–sixth and sixth–seventh vertebral interspaces. The sacral plexus, ventrolateral to the sacrum, was identified using electrolocation. Anesthesia was monitored using heart rate (HR), invasive blood pressure, electrocardiography, expired gases, respiratory frequency and esophageal temperature by an investigator unaware of the group allocation. Pelvic limb amputation by coxofemoral disarticulation was performed. Dogs that responded to surgical stimulation (>10% increase in HR or arterial pressure) were administered fentanyl (2 μg kg?1) intravenously for rescue analgesia. Postoperative pain was assessed at extubation; 30, 60 and 120 minutes; and the morning after surgery using a visual analog scale (VAS).

Results

The number of intraoperative fentanyl doses was fewer in the bupivacaine group (2.7 ± 1.1 versus 6.0 ± 2.2; p < 0.01). Differences in physiologic variables were not clinically significant. VAS scores were lower in bupivacaine dogs at extubation (0.8 ± 1.9 versus 3.8 ± 2.5) and at 30 minutes (1.0 ± 1.4 versus 4.3 ± 2.1; p < 0.05).

Conclusions and clinical relevance

Psoas compartment (lumbar plexus) and sacral plexus block provided analgesia during pelvic limb amputation in dogs.  相似文献   
89.
90.
Although horses are affected by cranial nerve disease, our understanding of these structures' imaging anatomy is limited, and the optimal modality for imaging of each of these nerves is unclear. The aim of this study was to describe the imaging appearance of the equine cranial nerves on high‐resolution 1.5T magnetic resonance imaging (MRI) and computed tomography (CT) scans of a cadaver head, and with these as standards, examine the utility of MRI and CT performed in clinical cases. High‐resolution MRI and CT images were prospectively acquired of the head of a normal Thoroughbred gelding following euthanasia. Ten clinical cases undergoing high‐field MRI under general anaesthesia and 10 clinical cases undergoing CT in the standing horse under sedation were retrospectively evaluated by three reviewers to assess cranial nerve visibility. On high‐resolution, thin‐slice, MRI scans of the normal cadaver head, each of the 12 cranial nerves and their topographic location could be appreciated. On high‐resolution cadaver CT, cranial nerves II, V and VII were clearly visible, but others were less easily identified; osseous structures were clearly visualised. Clinical MRI and CT allowed for variable visualisation of the cranial nerves, dependent on the sequence and the orientation of scan planes. High‐field MRI allowed excellent visualisation of equine cranial nerves, whereas CT allowed for more detailed visualisation of the osseous canals and foramina. In live horses, the ability to identify all 12 nerves is challenging with either MRI or CT; however, high‐field MRI enables better visualisation of the nerve bundles than CT.  相似文献   
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