驼背鲈鳃丝的光镜、扫描和透射电镜观察

应用光学显微镜、扫描电镜和透射电镜对驼背鲈Cromileptes ahivelis鳃丝的组织结构、表面形态特征及鳃小片超微结构进行了观察.结果表明驼背鲈鳃丝和鳃小片的表面结构和超微结构与其他硬骨鱼类的基本相似,鳃丝表面分布有众多规则或不规则的环形微嵴、沟、坑、孔等结构.鳃丝排列紧密,末端膨大;鳃丝呼吸上皮细胞薄,其下具有丰富的毛细血管,胞间具分泌细胞开口.鳃小片表面呈褶皱状、凹凸不平,排列在鳃丝两侧.鳃小片是由上下2层单层呼吸上皮细胞以及把它们撑开的支持细胞所构成,泌氯细胞大量分布在鳃丝、鳃小片上,并有开口通往外界.讨论了驼背鲈鳃结构与功能的密切关系.     

Haemangiopericytoma: histological spectrum, immunohistochemical characterization and prognosis

Canine haemangiopericytoma (CHP) is a vascular neoplasm thought to be derived from pericytes. The histological pattern and immunohistochemical profile were studied in 31 CHPs. Twenty-three subjects were followed for 2 years to evaluate the correlation among tumour location, histotype, immunostaining and outcome of the disease. Of the 31 CHPs examined, 20 exhibited a perivascular whorled pattern, 8 were storiform and 3 were epithelioid. All tumours were positive for vimentin and negative for cytokeratin, factor VIII-related antigen, glial fibrillary acidic protein and S-100 protein. Seventeen CHPs were positive for actin and nine co-expressed desmin. Six CHPs were also positive for CD34 antigen. The panel of immunohistochemical markers used confirmed the vascular lineage of CHP and aided in the exclusion of other mesenchymal tumours. Of the 23 dogs submitted to follow-up, 6 had recurrence or metastases of the primary tumour. The epithelioid pattern or a noncutaneous location were associated with a poorer prognosis.     

Immunophenotyping lymphomas in dogs: a comparison of results from fine needle aspirate and needle biopsy samples

The reliability of utilizing cytologic samples for immunophenotyping canine lymphomas was evaluated by a systematic comparison of results from fine needle aspirate (FNA) to needle biopsy specimens stained by immunochemical methods. The specific reactivity of a selected panel of 12 antibodies to cell surface markers and intermediate filaments was assessed in 11 dogs by comparing cytologic to histologic samples. There was excellent correlation of results between immunostained cytologic and histologic samples. FNA sampling is a simple, noninvasive method for determining the lymphoid phenotype in canine lymphoma. In addition, this technique may be useful as a cytodiagnostic aid in differentiating lymphoid from non-lymphoid tumors and in assessing neoplastic vs. reactive or hyperplastic processes.     

Malformations of the gill filaments of the ruffe Gymnocephalus cernuus (L.) (Pisces) caused by echinostomatid metacercariae

In parasite surveys of fishes from Lake Balaton and its tributaries in Hungary, infections with metacercariae of a species of the digenean genus Echinochasmus (Trematoda: Echinostomatidae) were found in seven species of fish. In ruffe, Gymnocephalus cernuus, malformations of the gill filaments apparently caused by these infections were observed. These malformations were in the form of bifurcations of the filaments at about their mid‐length. At the point where the filaments bifurcate, an Echinochasmus metacercaria was always embedded in the cartilaginous ray of the gill filament. All specimens of the ruffe were found to be infected by these metacercariae, and each ruffe specimen was infected by 30–300 metacercariae. Such a bifurcation was found in all of the ruffe specimens, but, apart from these gill malformations, the metacercariae produced only local changes in the cartilage. In the other six infected fish species, only local signs were observed in the cartilage. Experimental infections of chicks with metacercariae resulted in the finding of the sexual adult (marita) of an unidentified species of Echinochasmus. ITS sequences of the adult and metacercaria corresponded with each other, and also with a cercaria isolated from a gravel snail (Lithoglyphus naticoides), with a 99.5–100% similarity.     

光照对中国南北方萱藻丝状体生长发育影响的比较

通过分离、培养我国北方海域(烟台、青岛)和南方海域(舟山、温州)的萱藻丝状体,比较研究了不同光强[7.2、21.6、36.0、50.4、64.8、86.4、108.0和129.6μmol/(m2·s)]和不同光周期(8L:16D、10L:14D、12L:12D、14L:10D和16L:8D)对我国南北方萱藻丝状体生长及发育的影响。结果表明:(1)过高[≥108.0μmol/(m2·s)]或过低[≤21.6μmol/(m2·s)]光强条件均不利于我国南北方萱藻丝状体的快速生长;(2)我国南北方萱藻丝状体生长的最适光强条件相同,在64.8μmol/(m2·s)条件下培养20 d后,其丝状体的增重倍比和日均增长率均达到最大值;(3)我国南北方萱藻丝状体发育的最适光强条件均为36.0μmol/(m2·s),培养20 d后,烟台、青岛、舟山和温州的萱藻丝状体的孢子囊枝比例均达到最大值,分别为34.72%±0.91%、35.06%±1.17%、35.37%±0.59%和34.33%±0.41%;(4)我国南北方萱藻丝状体生长的最适光周期条件不同,培养20 d后,北方萱藻丝状体的增重倍比和日均增长率均在14L:10D条件下达到最大值,分别为82.75%±2.39%、3.00%±0.36%和81.28%±4.53%、3.04%±0.49%,而南方均在16L:8D条件下达到最大值,分别为89.52%±0.88%、3.18%±0.30%和88.66%±7.09%、3.22%±0.26%;(5)经过20 d的培养观察,我国北方萱藻丝状体发育的适宜光周期范围为8L:16D~10L:14D,而南方的适宜光周期范围为10L:14D~12L:12D。     

甲鱼养殖场抗污螺旋藻的分离及生长特性研究

从嘉兴市某温室甲鱼养殖场废水储存池中分离出1株螺旋藻JXSC-S1。通过与典型钝顶螺旋藻品系进行比较,确定该藻种的藻丝颜色、形状、螺距、螺宽、细胞大小等符合钝顶螺旋藻(Spirulina platensis)的形态特征。在Zarrouk培养基中,JXSC-S1的生长速率为1.64/d,生长代时为13.96 h,与典型钝顶螺旋藻种S6、S2相似,高于Ns-90020。在温室甲鱼废水中,JXSC-S1的生长速率、外观颜色和藻丝特征都与在Zarrouk培养基中相差不大,远高于S6(0.33/d),而Ns-90020基本不长,S2死亡。上述结果表明,该本地藻种JXSC-S1可以在温室甲鱼废水中快速生长,在用温室甲鱼废水代替昂贵的Zarrouk培养基高效规模生产优质饲料蛋白方面有很大应用潜力。     

抗生素对共培养的萱藻丝状体和膨胀色球藻生长的影响

为抑制萱藻丝状体扩增过程中出现的膨胀色球藻的生长,采用实验生态学方法,研究了链霉素、氨苄青霉素、卡那霉素、庆大霉素和氯霉素等5种常用抗生素对共培养条件下的萱藻丝状体和膨胀色球藻生长的影响。结果显示,(1)链霉素浓度为100μg/mL时可以显著抑制膨胀色球藻生长,而不影响萱藻丝状体的生长;(2)氨苄青霉素和庆大霉素对膨胀色球藻产生明显抑制作用的浓度均为100μg/mL,对萱藻丝状体产生抑制作用的浓度分别为100和500μg/mL;(3)10μg/mL卡那霉素可强烈抑制膨胀色球藻生长,而萱藻丝状体没有出现被抑制的现象;(4)氯霉素对膨胀色球藻和萱藻丝状体均有较强的抑制作用,10μg/mL可以对膨胀色球藻的生长产生显著抑制,浓度达到50μg/mL后,萱藻丝状体生长受到抑制。研究表明,链霉素(100μg/mL)、卡那霉素(100μg/mL)和氯霉素(10μg/mL)可以用于降低萱藻种质保存和扩增过程中萱藻丝状体被膨胀色球藻污染的风险。     

二氧化锗对共培养萱藻丝状体和硅藻生长的影响

为抑制萱藻丝状体保存和扩增过程中出现的小伪菱形藻与碎片菱形藻的生长,本实验应用实验生态学方法,分别建立了丝状体与小伪菱形藻、丝状体与碎片菱形藻、丝状体与小伪菱形藻和碎片菱形藻的共培养体系,研究了1.00～4.00μg/mL二氧化锗(GeO_2)对共培养条件下丝状体生长发育及附生硅藻生长的影响。结果显示:(1)处理萱藻丝状体和硅藻共培养体系的适宜GeO_2浓度为1.00～2.50μg/mL,各实验组14 d的硅藻抑制率均高于67.33%±5.18%,且丝状体生长发育良好,2.00μg/mL为最适浓度,此浓度下丝状体日均增长率最高,在各培养体系中均大于11.00%,且诱导后孢子囊枝比例和孢子囊直径分别为57.47%±5.31%和(24.55±1.01)μm,与对照组差异不显著;(2) 3.50和4.00μg/mL GeO_2虽对硅藻抑制效果更佳,但同时也会抑制丝状体生长和后期孢子囊的形成与发育,其中4.00μg/mL GeO_2可导致丝状体死亡;(3)碎片菱形藻较小伪菱形藻对GeO_2更敏感。实验14 d,各浓度GeO_2对碎片菱形藻的抑制率为(82.10%±2.40%)～(96.35%±0.79%),均高于同浓度GeO_2对小伪菱形藻的抑制率;同时在丝状体与小伪菱形藻和碎片菱形藻的共培养体系中,碎片菱形藻占硅藻比例随GeO_2浓度升高而相应下降。