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排序方式: 共有6101条查询结果,搜索用时 15 毫秒
31.
作者前已报道蕲蛇及其伪品滑鼠蛇的鉴别,又据报道有些省发现蕲蛇商品药材中混有烙铁头、山烙铁头两种蛇的干燥体。作者对这两种混淆品与蕲蛇在体表花纹、鳞片以及骨骼的形态与组织特征等方面进行了鉴别研究。 相似文献
32.
Forty melanocytic lesions were examined in a pilot study, which was followed by a final series of 100 consecutive melanocytic lesions, in order to evaluate the inter-observer reproducibility of the histological criteria proposed for the dysplastic naevus. The specimens were examined in a blind fashion by four observers. Analysis by kappa statistics showed poor reproducibility of nuclear features, while reproducibility of architectural features was acceptable, improving in the final series. Consequently, we cannot apply the combined criteria of cytological and architectural features with any confidence in the diagnosis of dysplastic naevus, and, until further studies have documented that architectural criteria alone will suffice in the diagnosis of dysplastic naevus, we, as pathologists, shall avoid this term. 相似文献
33.
This study compares the histology of the plantar-digital nerve supplying the third web space in asymptomatic patients with those who have clinically diagnosed Morton's metatarsalgia. Despite several studies concentrating on the histological changes in the interdigital nerve, the relevance of these changes is a matter of contention while the exact pathological process responsible for the symptoms has not been determined. The histological findings in control patients were identical to Morton's patients with the exception of demyelination, which was more common in the Morton's group. This suggests that the characteristic nodule and fibrotic changes seen in the interdigital nerves of patients with Morton's neuroma cannot account for the symptoms and that the changes seen in the neurovascular bundle are degenerative in origin and are found in asymptomatic patients. 相似文献
34.
The effects of chemical fixation are known to alter MR parameters, such as relaxation times and the apparent diffusion coefficient (ADC) of water. It is often assumed that such changes are reversible after samples have been reimmersed in a buffer solution for a sufficient period of time. In this study we characterize the changes associated with fixation of single Xenopus laevis oocytes and their subsequent reimmersion in buffer. Substantial reductions in both T(1) and T(2) values were measured for all compartments of the cell after fixation, with the cytoplasm showing larger changes than the nucleus. After reimmersion in buffer, there were small but statistically significant differences in MR parameters between fresh and reimmersed cells. Experiments with a gadolinium (Gd) contrast agent showed evidence of irreversible changes in the permeability of cellular membranes to small molecules. 相似文献
35.
Role of transrectal ultrasonography in the evaluation of azoospermic men with low-volume ejaculate. 总被引:2,自引:0,他引:2
Gil Raviv Yoram Mor Jacob Levron Shai Shefi Dorit Zilberman Jacob Ramon Igal Madgar 《Journal of ultrasound in medicine》2006,25(7):825-829
OBJECTIVE: The purpose of this prospective study was to evaluate the incidence of distal ejaculatory system defects with transrectal ultrasonography (TRUS) among patients evaluated for azoospermia. METHODS: Forty-two patients with low-volume ejaculate and azoospermia were evaluated by physical examination, serum follicle-stimulating hormone and luteinizing hormone level determination, karyotyping, selective screening for cystic fibrosis mutations, and TRUS. RESULTS: On physical examination, in 29 patients (69%), either 1 (12 patients) or both (17 patients) of the vasa deferentia could not be palpated. In the group of 17 patients with bilateral involvement of the vasa deferentia, the ultrasonographic imaging universally showed bilateral absence or hypoplasia of the seminal vesicles with bilateral agenesis of the vasa deferentia and nonvisualization of both ejaculatory ducts. In the patients with a unilateral abnormality on physical examination, the ultrasonographic imaging showed absence of the ipsilateral seminal vesicle in 7 patients and the hypoplastic seminal vesicle in 5. In the group of 13 patients with normal physical examination findings, a variety of obstructive causes were diagnosed by TRUS examination. CONCLUSIONS: According to this study, TRUS appears to be a sensitive method for evaluating the anatomy of the distal ejaculatory system. Its safety and low costs make it a good alternative to the other invasive and expensive methods. 相似文献
36.
A new approach to the analysis of tissue-implant interaction is presented using rat gluteal muscle as implantation site and using monoclonal antibodies to identify and quantify cells around the implant. The method can be used for comparative studies on biocompatibility. In this methodological investigation, pure titanium (Ti) was studied, revealing an initial response of macrophages, followed by the formation of a fibrous membrane, in which, even at 50 and 70 d, la-expressing cells and suppressor T-lymphocytes were present. 相似文献
37.
69例睾丸扭转诊断与治疗 总被引:6,自引:0,他引:6
目的提高睾丸扭转诊断及治疗水平。方法对69例睾丸扭转患者的临床资料进行回顾性分析。结果8例12h内手术者,睾丸均存活;6例12—24h手术者,3例睾丸存活;39例超过24h手术者仅7例睾丸存活。未手术者16例,随访7例扭转睾丸均发生不同程度萎缩,尚未发现生育能力受影响者。结论早期诊断、及时治疗是提高疗效的关键。睾丸移植是治疗双侧睾丸扭转后功能性无睾症的一种有效方法。 相似文献
38.
LN Weinberger MJ Zirwas JC English III 《Journal of the European Academy of Dermatology and Venereology》2007,21(2):156-162
Male genital oedema can be defined as swelling or the appearance of swelling of the scrotum and/or the penile shaft and prepuce. Despite the various causes of genital oedema reported in the published work, a concise approach to the evaluation and management has not been sufficiently addressed. 相似文献
39.
肝动脉解剖变异在中晚期肝癌介入治疗中的意义 总被引:1,自引:0,他引:1
目的 探讨放射学肝动脉解剖变异及其在中晚期肝癌介入导管治疗中的临床意义。方法 回顾性分析125例中晚期肝癌肝动脉造影表现及其介入治疗资料。结果 125例中107例(85.6%)有典型肝动脉分布。肝动脉变异18例(14.4%),其中肝右动脉变异10例(8%),而又以肝右动脉始于肠系膜上动脉者最多,占6.4%。副肝左动脉变异1例(0.8%)。肝左动脉和肝右动脉同时变异2例(1.6%)。肝总动脉变异3例(2.4%)。胃十二指肠动脉起自肝右动脉和腹腔动脉各1例(1.6%)。对123例成功进行了肝动脉化疗栓塞,2例肝右动脉变异因角度关系超选插管未成功。结论 认识肝动脉解剖变异有助于提高插管的成功率和中晚期肝癌的介入治疗疗效。 相似文献
40.
Healthy lungs tolerate repetitive collapse and reopening during short periods of mechanical ventilation 总被引:3,自引:0,他引:3
V. Taskar J. John E. Evander P. Wollmer B. Robertson B. Jonson 《Acta anaesthesiologica Scandinavica》1995,39(3):370-376
The possible occurrence of lung damage if alveolar units are allowed to collapse and reopen breath by breath during mechanical ventilation with normal tidal volumes was investigated. Anaesthetised, paralysed, open chest rabbits were subjected to either intrathoracic negative (NEEP; n=6) or positive (PEEP; n=6) end-expiratory pressure during volume controlled mechanical ventilation. Both experimental settings were preceded by a 30 min control period and followed by a 30 min recovery period during which a PEEP of 0.2 kPa was maintained. Pao2 and pulmonary compliance deteriorated significantly in the NEEP group during the experimental period and compared to ventilation with PEEP. Partial restoration of lung mechanics and blood gases was achieved during the recovery period. After an alveolar recruitment manoeuvre, this recovery was complete. Lung clearance studied by depositing an aerosol of technetium-99m-labelled diethylenetriamine pentaacetate (99m Tc-DTPA) in the alveoli, was significantly faster during ventilation with NEEP compared to the PEEP group ( P =0.0002) as well as the control period ( P = 0.0029). It did not recover completely during the recovery period but remained significantly faster. light microscopic histology was normal in both groups with no evidence of inflammation or epithelial disruption. We conclude that previously healthy rabbit lungs show only a transient disturbance of lung mechanics and blood gases with repetitive collapse and re-expansion. The integrity of the alveolar rnicrostructure is preserved. The disturbance in the alveolo-capillary permeability persists and may indicate surfactant related alveolo-capillary barrier dysfunction. 相似文献