排序方式： 共有11条查询结果，搜索用时 171 毫秒
1.
西伯利亚鲟性腺早期发生、分化、发育的组织学观察 总被引：4，自引：0，他引：4
利用组织学方法研究人工繁育、养殖的西伯利亚鲟(Acipenser baerii)仔、幼、成鱼性腺发育过程中原始生殖细胞(Primordial germ cells,PGC)的迁移,生殖褶的生成,性腺雌雄分化和发育过程。结果表明,西伯利亚鲟于3dph(Days post-hatch)时,PGC以单细胞的形式存在于仔鱼卵黄囊上方两中肾管之间,10dph时其迁移到背侧的腹膜上皮上,13dph时其沿腹膜上皮朝肾管区下方迁移,22dph时生殖嵴形成,31dph时原始性腺形成,40～60dph时原始性腺发育形成裂腔,PGCs沿腔壁排列,裂腔经过进一步发育并从背离腹膜上皮的底端慢慢愈合成实体,90dph时原始性腺中出现生殖上皮和性细胞,150dph时脂肪细胞和血管增多,210dph时性腺出现2种不同的表面结构,性腺开始分化。本研究利用组织学方法借鉴鱼类性腺分期标准,将西伯利亚鲟性腺分化划分为0期和Ⅰ～Ⅵ期,并描述了各期精巢、卵巢的结构变化以及细胞形态学特征。 相似文献
2.
云南主要地方牛种横纹肌组织形态学研究 总被引：4，自引：1，他引：3
采用组织学、电镜方法对云南主要地方牛种大额牛、云南瘤牛、中甸牦牛、迪庆黄牛和中甸牛扁牛的肌纤维特性作了系统研究。５个牛种背最长肌的肌纤维直径（μｍ）分别为５７．４８±１．１５、１０９．４５±１．８４、１００．３８±６．２５、９０．３８±５．３１和９７．３５±９．６２;肌纤维密度（根／ｍｍ２）分别为２０１．５４±２．６６、１１５．４５±４．０４、１０６．３０±１０．１０、９０．３８±５．３１和９２．３５±９．６２;肌束内纤维数（根）分别为７３．２３±８．９０、３４．３２±８．７７、３６．３２±８．３０、４７．６２±８．９０和４０．４０±８．７９。肌节长度（μｍ）以大额牛公牛最长（１．７０６５）,云南瘤牛去势公牛居中（１．４６７０）,云南瘤牛公牛最短（１．２０５０）。 相似文献
3.
Giancarlo Avallone Damiano Stefanello Roberta Ferrari Paola Roccabianca 《Veterinary and comparative oncology》2020,18(1):3-8
Subcutaneous spindle cell tumours characterized by whorling growth patterns are common in dogs and are identified as a distinct entity. These tumours were misnamed as hemangiopericytomas (HPCs) because of some minor morphological parallels with their human counterparts. In veterinary medicine, the cell of origin of HPC has been under debate for a long time. Some authors have suggested a perivascular origin while others a perineural one. The evidence of the orientation of the neoplastic cells around the vessels and the expression of contractile proteins supported a perivascular origin while S100 expression and an inconsistent vascular connection supported a perineural origin. Despite the morphological similarities with peripheral nerve sheath tumours in humans, the perineural origin was supported mainly by the expression of markers with low specificity. On the contrary, the majority of studies have supported the perivascular origin of ‘old’ canine HPC. Since a variable degree of myoid‐pericytic differentiation was described, the term perivascular wall tumours (PWTs) were suggested to substitute HPC. Once the diagnostic criteria of PWTs were defined, the clinical behaviour and prognostic variables were investigated, demonstrating differences as compared with the group of canine soft tissue sarcomas (STSs) in general. PWTs are less aggressive, mostly locally invasive, and rarely metastasizing. Their behaviour seems to be less influenced by histological grade, suggesting that canine STSs are heterogeneous. The study of the biological behaviour of specific STS tumour types may be valuable in detecting differences which have passed unnoticed when STSs have been studied concomitantly. 相似文献
4.
双峰驼卵巢的组织结构 总被引：5，自引：1，他引：5
应用组织学方法对双峰驼卵巢的形态结构进行了显微与亚显微观察。结果显示 ,双峰驼卵巢表面被覆单层立方至单层扁平的生殖上皮 ,无排卵窝 ,上皮下为致密结缔组织白膜 ,卵巢实质由外周的皮质和中央的髓质构成。皮质中原始卵泡和初级卵胞数量稀少 ,其分布位置更靠近皮质中层 ,偶见同一卵泡内含 2个卵母细胞。体积大小和发育阶段不同的次级卵泡与三级卵泡闭锁时 ,所发生的形态变化不一致 ,可出现实心和囊状 2种闭锁卵泡。黄体中以粒性黄体细胞占优势 ,其细胞质中含大量脂质泡而呈海绵样。卵巢髓质中除含大量血管外 ,还见卵巢网分布 相似文献
5.
Antony S. Moore Angela E. Frimberger David Taylor Neill Sullivan 《Veterinary and comparative oncology》2020,18(3):402-408
Published outcomes for dogs with specifically high‐grade mast cell tumours (MCTs), controlled for clinical stage, are few. Clinical outcomes for 49 dogs with Kiupel high‐grade, clinical stage I, cutaneous MCTs were evaluated. Median survival time (MST) was 1046 days; 1 and 2‐year survival rates were 79.3% and 72.9%, respectively. At study end 24 dogs had died, 23 dogs were alive (median follow‐up 980 days) and 2 dogs were lost to follow‐up. Death was considered MCT‐related in 14 of 20 dogs with a known cause of death. Local tumour recurrence developed in nine dogs (18.4%); regional lymph node metastasis occurred in six dogs (12.2%); and a new MCT developed in 15 dogs (30.1%). Tumour location, histologic margin size and use of chemotherapy did not affect MST; increasing mitotic count (P = .001) and increasing tumour diameter (P = .024) were independently negatively prognostic. Six dogs that developed lymph node metastasis after surgery had worse MST (451 days) than 42 dogs that did not develop metastasis (1645 days); (P < .001). Our study suggests that dogs with local surgical control of clinical stage I histologically high Kiupel grade cutaneous MCT may have a long survival time; especially those with smaller tumours and a lower mitotic count. Our results suggest that evaluation of staging information and mitotic count may be equally helpful as histologic grading when making a prognosis; and highlight the importance of not relying on histologic grade alone when predicting survival for dogs with MCT. 相似文献
6.
Evaluation of histological grade and histologically tumour‐free margins as predictors of local recurrence in completely excised canine mast cell tumours 
下载免费PDF全文
下载免费PDF全文 L. Donnelly C. Mullin J. Balko M. Goldschmidt E. Krick C. Hume D. C. Brown K. Sorenmo 《Veterinary and comparative oncology》2015,13(1):70-76
Completeness of mast cell tumour (MCT) excision is determined by assessment of histologically tumour‐free margins (HTFM). The HTFM width necessary to prevent local recurrence (LR), recognized as histologic safety margin (HSM) in human oncology, has not been defined. We hypothesized that HTFM width would correlate with risk for LR and high‐grade tumours would require wider HTFM than low‐grade tumours. Records of dogs with completely excised MCTs were included. Signalment, two‐tier tumour grade, tumour size, HTFM width, recurrence and therapy data was collected. High‐grade (n = 39) tumours were more likely to recur than low‐grade (n = 51) tumours (35.9% versus 3.9%), P < 0.0001, with no association between HTFM width and LR. Twenty‐nine percent of low‐grade tumours had HTFM less than 3 mm; none recurred. Narrow (≤3 mm) histologic margins are likely adequate to prevent LR of low‐grade tumours. High‐grade tumours have significant risk of LR regardless of HTFM width. 相似文献
7.
李跃 《湖南农业大学学报(自然科学版)》2012,38(3):310-313
设对照组(未染毒)、低剂量组(约2.5支烟,每天染毒10 min)、中剂量组(约5支烟,每天染毒20 min)及高剂量组(约10支烟,每天染毒40 min)4个处理,将雄性SD大鼠置于气体染毒箱内行被动吸烟,研究卷烟烟气暴露对大鼠学习记忆功能及海马病理和脑源性神经营养因子(brain-derived neurotrophicfactor,BDNF)的影响。结果表明:染毒30 d,染毒组大鼠潜伏时间均显著短于对照组,BDNF表达显著高于对照组;染毒60 d,中剂量组大鼠潜伏时间显著短于对照组,BDNF表达显著高于对照组;染毒180 d,染毒组大鼠潜伏时间显著长于对照组,BDNF表达显著高于对照组;不同剂量处理大鼠的海马HE染色均无明显变化,大鼠的海马组织均无器质性损伤;短期烟气暴露可提高大鼠学习记忆功能,随染毒时间的延长,大鼠学习记忆功能下降,该作用与海马BDNF的表达密切相关。 相似文献
8.
廖富 《华南农业大学学报》1999,20(1):108-112
以不同浓度苏芸金杆菌伴孢晶体接种于４龄起蚕,观察研究家蚕细胞性中毒病的急性和慢性中毒症状及中肠组织细胞的病理变化过程及发病规律。蚕儿食下伴孢晶体６．５×１０＾－９ｗｈ ／Ｌ／Ｌ后,呈慢性中毒,可发现中肠细胞有明显的防御反应,部分蚕最终可修复受损中肠细胞导并使蚕儿恢复正常。 相似文献
9.
对18只法比兔生后舌和食管进行组织学观察的结果表明,免出生时舌背侧粘膜上皮未角化,并含有大量丝状乳头（平均高为135.7μm）和少量菌状乳头。固有膜不发达。舌肌为纵向、横向及垂直方向排列的横纹肌。舌腹侧粘膜表面平滑。15日龄以后,舌背侧菌状乳头高为200～521μm,其顶部直径为93～221μm。1日龄时,兔食管粘膜上皮只有4～5层细胞（平均厚28.5μm）。60日龄时,已达30层左右（平均厚164.3μm)。固有膜与粘膜下层分界不清。肌层由内纵、中环、外纵3层组成。肌层随年龄增长而逐渐增厚,1日龄时平均厚度121.4μm,60日龄时平均厚度达750μm。 相似文献
10.
Retrospective evaluation of COX‐2 expression,histological and clinical factors as prognostic indicators in dogs with renal cell carcinomas undergoing nephrectomy 下载免费PDF全文
下载免费PDF全文 S. Carvalho A. L. Stoll S. L. Priestnall A. Suarez‐Bonnet K. Rassnick S. Lynch I. Schoepper G. Romanelli P. Buracco M. Atherton E. M. de Merlo A. Lara‐Garcia 《Veterinary and comparative oncology》2017,15(4):1280-1294
Limited veterinary literature is available regarding prognostic markers for canine renal cell carcinoma (CRCC). We retrospectively evaluated COX‐2 expression, histological and clinical features associated with prognosis of CRCC. Sixty‐four cases post‐nephrectomy were included, 54 had histopathological assessment and 30 had COX‐2 immunostaining performed. Eight dogs (13%) had metastatic disease at initial diagnosis. Twenty‐seven dogs (42%) received adjuvant therapy after nephrectomy. On univariate analysis, COX‐2 expression, mitotic index (MI), histologic type, vascular invasion, neoplastic invasiveness and metastasis at diagnosis were significantly associated with overall median survival time (MST). COX‐2 score (COX‐2 score > 3 MST 420 days versus 1176 days if COX‐2 score <3; P = 0.011) and MI (MI > 30 MST 120 days versus 540 days for MI < 30; P = 0.003) were the only variables associated with CRCC outcome on multivariate analysis. The addition of MI and COX‐2 immunostaining to standard histopathological evaluation would help predicting outcome in CRCC patients. 相似文献