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91.
报告鼻腔鼻窦非上皮源性恶性肿瘤7 例,其中恶性黑色素瘤2 例,恶性神经鞘瘤2 例,非霍奇金氏淋巴瘤2 例,平滑肌肉瘤1 例。因鼻腔鼻窦恶性黑色素瘤罕见,故易误诊,其中1 例因高度疑为此病,经病检证实,及时准确切除了瘤体,术后存活5 年余;恶性神经鞘瘤临床确诊主要依靠病检,诊断平滑肌肉瘤则需结合免疫组化检测,随免疫组化的开展,非霍奇金氏淋巴瘤的临床与病理诊断符合率已有提高,前三者治疗以手术切除为主,非霍奇金氏淋巴瘤则可先化疗再局部放疗。  相似文献   
92.
了解胸锁乳突肌和副神经的解剖关系及在痉挛性斜颈中的作用,为手术治疗痉挛性斜颈的切口 和方法提供解剖依据。方法:观测活体成人男女各100名例胸锁乳突肌长度、宽度,标本65具(男35具,女30具) 该肌长、宽和厚度及其周围结构。结果:见乳突尖向胸锁乳突肌前缘4 cm(上 1/4下 3/4交点)和向下至后缘5 cm (上中1/3交点)处连线深面有副神经(80%±15%),该处是切断胸锁乳突肌及其副神经肌支的最佳部位之一。二腹 肌后腹深面为高位结扎切断副神经点,若再向上易伤颈内静脉。在胸锁乳突肌深面的副神经最大横径为(2.3± 0.5)mm。结论:沿副神经的体表投影线,设计出和投影线相应的手术切口,切断副神经和部分胸锁乳突肌是治疗痉 挛性斜颈的较好部位。  相似文献   
93.
综述了番红花属植物近期的化学及药理研究情况,主要集中在对其柱头中类胡萝卜素及胡萝卜素类化合物的分离及鉴定上;对一些化合物抗癌活性的研究相对集中。  相似文献   
94.
评价低温保存板层角膜移植材料的效果。方法将15只人尸角膜分三组保存2年:4℃甘油脱水法,角膜液氮冷冻法,全眼球液氮冷冻法。并做透射电镜观察。结果第一组中,角膜胶原纤维排列紊乱,疏松,缺乏连续性,可见广纤维变性,纤维间可见极低电子密度灶。  相似文献   
95.
Summary. Perinatal hypoxia is known as a high risk factor for the development of long-lasting abnormalities in dopaminergic system. The early developmental alterations of dopamine (DA) metabolism induced by hypoxia could contribute to these abnormalities. To understand the hypoxia-induced changes of intra- and extracellular dopamine levels and its main metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), in immature dopaminergic neurons, we compared these changes in rat mesencephalic and diencephalic cell cultures on day in vitro (DIV) 2 (immature cells), DIV 8 and DIV 13 (mature cells). Cell cultures were exposed to an oxygen-free gas mixture in a Billups chamber for 2–4 hours. Mature cell cultures responded to hypoxia with an increase of DA levels in the cells and in the medium during the first 45 min (by an average of 57 and 114% respectively). Thereafter, DA levels decreased, and returned to the baseline within the next 30 min. The cellular DA levels continued to decrease up to 15% of the baseline during 255 min hypoxia whereas the extracellular DA content stabilized at the prehypoxic levels. Immature cell cultures (DIV 2) in contrast to mature ones, were unable to maintain normal extracellular DA levels during hypoxia and showed a decrease of the cellular and extracellular levels to 50% of the prehypoxic levels. DOPAC and HVA changes mimick, however, at a lower level, the pattern of DA changes during the exposure to hypoxia. In principle, in the diencephalic cell culture similar effects of hypoxia exposure on the investigated parameters were found (studied during 0–120 min). The present study demonstrates that mature and immature dopaminergic cells differ in the regulation of the extra- and intracellular DA levels during hypoxia. In immature cells the low synthetic capacity of tyrosine hydroxylase and the deficient capacities of the transport and storage processes result in decreased extracellular DA levels. This could be an important factor for the long-term modulation of the expression of tyrosine hydroxylase and subsequent long-term behavioral and/or neurological abnormalities induced by perinatal hypoxia. Received June 8, 1998; accepted July 21, 1998  相似文献   
96.
Paget病19例   总被引:9,自引:0,他引:9  
Fu M  Gao S  Wang P 《中华外科杂志》1999,37(7):429-431
目的 提高对Paget病的诊治水平。方法 回顾性分析1987年至1997年收治的19例Paget病的临床表现及诊治方法。结果 本组乳腺Paget病6例,乳腺外13例,其中阴茎,阴囊11例,腹股沟处1例,肛周肛管1例。随访时间0.5-11年,平均5年4个月,随访中3例复发者,其截端切片病理检查均可见病变组织,另1例死于其他疾病。  相似文献   
97.
IntroductionLipoprotein(a)[Lp(a)]consistsofanLDLparticle,inwhichapolipoprotein(a)isatachedtoapolipoproteinB-100throughadisulf...  相似文献   
98.
Rates of prostate cancer (PCa) have increased so dramatically over the last decade that the age adjusted incidence rate for PCa is now greater than that any other cancer among men in the United States. This review, published as a three part series, provides a state-of-art assessment of the PCa problem in its divergent aspects.Part 1 covers epidemiology, incidence and progression. Several epidemiological studies have demostrated that first degree male relatives of men with PCa are at increased risk of developing the disease. Familial and genetic factors as well as medical, anthropometric, dietary, hormonal and occupational factors involved in PCa are discussed. Postmortem examination of the prostate in men without evidence of PCa documented a high frequency of adenocarcinoma. Latent disease occurred as early as the second decade of life. Although there is no significant difference in incidence between Caucasian and African-American males, high grade prostatic intraepithelial neoplasia (HGPIN) is higher in the latter group. While dietary fat, androgens and certain environmental factors may be determinants for PCa, the exact mechanism of tumorigenesis is still relatively unknown. The current thinking of the role of genomic instability, chromosomal alterations, tumor suppressor genes and the androgen receptor are explored.  相似文献   
99.
Three cases of "Top of the basilar" syndrome are reported. The clinical manifestations included the consciousness disturbance, pupillary and oculomotor abnormalities. One of the 3 cases got cortical blindness. It is emphasized that the possibility of the TOB syndrome should be considered when unconsciousness arose suddenly, accompanied by lid, pupil and oculomotor disturbances without the motor and sensory disturbances. Usually, a bilateral symmetric butterfly hypodensity could be found in the thalamus on CT scan. In addition. It was valuable findings that the infarct lesions have been shown in the mesencephalon, pons, cerebellum, occipital and medial temporal lobe on CT scans.  相似文献   
100.
Campylobacter jejuni is a major cause of human enteritis which mimics the inflammatory bowel disease (IBD). In this study, microstructural changes on the surfaces of the murine gastrointestinal tract persistently colonized by Campylobacter jejuni, strain GJ-S131, were investigated by using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results revealed that the appearance of the gastrointestinal mucosa in both BALB/C and KM mice resembled that in human with inflammatory bowel disease. Under SEM, the mucosa of the jejunum and ileum, with broken or distorted villi had a "worm eaten" look; crypts were irregular in shape and size, and the mucosa showed atrophy, especially in the colon. Epithelial junctions demonstrated furrows, clefts or deep crevasses, with exudates containing a large number of leukocytes. Cytologic appearances were characterized by microvilli dysplasia and/or atrophy, patchy erosions or necrosis and pelade-like appearance due to absence of microvilli, which were similar to the findings under TEM.
  相似文献   
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