排序方式： 共有28条查询结果，搜索用时 125 毫秒
11.
12.
Raelyn Walczak Matthew Paek Jantra Suran Joseph T. Amory Swan Specchi Melissa Sanchez 《Veterinary radiology & ultrasound》2020,61(3):E26-E30
An adult cat was presented for acute history of vomiting and collapse. Radiographs showed the presence of air within small intestinal walls and arborizing gas patterns within the liver, compatible with pneumatosis intestinalis and presumed portal venous gas, respectively. An abdominal ultrasound the following day was suggestive of gas within the intestinal wall, however, gas within the hepatic vasculature, parenchyma, or biliary tree was not evident. Due to progressive clinical deterioration of the patient, the owners elected humane euthanasia. Necropsy revealed severe necrotizing hemorrhagic enterotyphlocolitis secondary to Clostridium difficile toxin. 相似文献
13.
Caroline Utermann Vivien A. Echelmeyer Ernest Oppong-Danquah Martina Blümel Deniz Tasdemir 《Marine drugs》2021,19(1)
It is widely accepted that the commensal gut microbiota contributes to the health and well-being of its host. The solitary tunicate Ciona intestinalis emerges as a model organism for studying host–microbe interactions taking place in the gut, however, the potential of its gut-associated microbiota for marine biodiscovery remains unexploited. In this study, we set out to investigate the diversity, chemical space, and pharmacological potential of the gut-associated microbiota of C. intestinalis collected from the Baltic and North Seas. In a culture-based approach, we isolated 61 bacterial and 40 fungal strains affiliated to 33 different microbial genera, indicating a rich and diverse gut microbiota dominated by Gammaproteobacteria. In vitro screening of the crude microbial extracts indicated their antibacterial (64% of extracts), anticancer (22%), and/or antifungal (11%) potential. Nine microbial crude extracts were prioritized for in-depth metabolome mining by a bioactivity- and chemical diversity-based selection procedure. UPLC-MS/MS-based metabolomics combining automated (feature-based molecular networking and in silico dereplication) and manual approaches significantly improved the annotation rates. A high chemical diversity was detected where peptides and polyketides were the predominant classes. Many compounds remained unknown, including two putatively novel lipopeptides produced by a Trichoderma sp. strain. This is the first study assessing the chemical and pharmacological profile of the cultivable gut microbiota of C. intestinalis. 相似文献
14.
15.
不同季节海鞘滤水率的测定 总被引：2，自引：0，他引：2
在桑沟湾用模拟现场流水法对滤食性附着生物玻璃海鞘和柄海鞘的滤水率进行了测定。结果表明，同一品种海鞘，在不同季节其滤水率随着水温的变化而变化。在实验水温范围内，以５月份水温在１７℃左右时海鞘滤水率最大，栖海鞘为３．１９ｌ／ｈ·ｉｎｄ（ｃｈｌ－ａ）和４．５３１／ｈ·ｉｎｄ（ＰＯＭ），玻璃海鞘为０．７３１／ｈ·ｉｎｄ（ｃｈｌ－ａ）和０．７６１／ｈ·ｉｎｄ（ＰＯＭ）．１１月和９月水温在７℃和２５℃左右时其滤水率均降低至１７℃时的１／３～１／５左右。由此反映出这两种海鞘的生理现象和生活规律及与环境因子的关系。 相似文献
16.
Renaux S Quéré P Buzoni-Gatel D Sewald B Le Vern Y Coudert P Drouet-Viard F 《Veterinary parasitology》2003,110(3-4):181-195
Primary infection with Eimeria intestinalis confers very effective immunity against further infections in rabbits. This study was designed to determine the onset of the immune response in primary-infected rabbits and to characterise the immune status of protected rabbits. Variations in kinetics of CD4+ and CD8+ T-cell subpopulations were followed after primary infection at the intestinal sites of penetration (duodenum) and development (ileum), in mesenteric lymph nodes (MLN) and in the spleen. The response against the parasite was measured by specific lymphocyte proliferation in the spleen and MLN and by determining specific IgG titres in serum. The mucosal immune response was strong after primary infection and was characterised by (i) transient increase in the percentages of intestinal CD4+ lymphocytes and MLN CD8+ lymphocytes 14 days PI and (ii) strong increase in the percentages of intestinal CD8+ lymphocytes from 14 days PI persisting throughout further infections. Extensive infiltration of the lamina propria with CD8+ lymphocytes was observed 14 days PI. The specific proliferative response started between 7 and 14 days PI in MLN but remained undetectable in spleens for up to 21 days, in contrast to “immunised” rabbits. The fact that systemic immune responses were low after primary infection, in contrast to indicators of mucosal immune responsiveness, suggests that protection of rabbits against E. intestinalis infection is due to an effective mucosal immune response, and that systemic responses that increase after successive infections are only reflections of repeated encounters with parasite antigens. 相似文献
17.
玻璃海鞘胚胎发育的研究 总被引：2，自引：0，他引：2
在显微镜下,对自然排放的的玻璃海鞘C iona intestinalis卵细胞和受精卵以及胚胎发育的整个过程进行了观察,结果表明:玻璃海鞘卵具有特殊的被囊细胞,未受精前的卵径为110μm左右,受精后为160~170μm;在20℃水温下,卵细胞从受精到蝌蚪幼虫孵出需16~18 h,幼虫的浮游时间约2 h,从附着到尾开始收缩约3 h,从尾开始收缩至变态约4 h,从开始变态到变态完全约7~9 d。 相似文献
18.
肠艾美耳球虫配子生殖与病理变化 总被引：2，自引：1，他引：1
用单个肠艾美耳球虫Eimeria intestimalis Cheissin 1984卵囊感染无球虫兔,获得纯种进行研究。1.肠艾美耳球虫的配子生殖阶段寄生于空肠和回肠,此时宿主组织有较严重病变。12指肠、结肠和盲肠未见虫体,但在感染后264小时见盲肠的个别绒毛内有1～3个配子体,可能属偶然现象。2.感染后180小时发现极少数早期配子体,感染后192小时出现少量配子体寄生在空肠和回肠的绒毛和腺上皮细胞内,感染后216至264小时,绒毛上皮和腺上皮细胞内多为配子体、合子和卵囊所取代。感染后216小时出现极少量卵囊,264小时则见有大量卵囊。3.感染开始时(感染后61～73小时),回肠、空肠绒毛上皮正常;腺上皮细胞出现少量滋养体和裂殖体。96至192小时后,肠绒毛上皮和腺上皮受侵害程度渐趋严重,肠绒毛变矮,绒毛上皮及腺上皮细胞肿大变空,细胞核消失。许多腺泡塌陷。感染后216～264小时,肠绒毛受侵害最为严重,空肠和回肠绒毛萎缩或消失,变为一层矮柱或立方形上皮细胞或全无上皮细胞覆盖的绒毛。固有层均质红染,或颗粒状。肠腺塌陷,数量减少,大小不一。腺腔内见有配子体、合子或卵囊残留,部分腺泡上皮细胞再生,细胞核增生成堆。12指肠、盲肠和结肠正常。 相似文献
19.
- During this study, the effects of epiphytic filamentous algae on the survival of demersal spawned fish eggs were investigated in one of the most important spawning grounds of herring in the western Baltic Sea, which is subject to intense and ongoing eutrophication.
- In coastal marine ecosystems all over the world, eutrophication is a primary water quality issue, often resulting in mass developments of bloom‐forming algae. Macro‐algal blooms have immense ecological effects, as they alter the structure and the function of an ecosystem. Numerous fish species are affected, as they depend on those coastal areas for spawning and as juvenile habitats.
- A comparison of the survival of herring eggs on two natural spawning beds re‐vealed an immense impact of a filamentous algal bloom. The mortality rate reached nearly 100% in the area with massive occurrence of filamentous brown algae.
- Hypothesizing that the presence of filamentous algae facilitates herring egg mortality, field and laboratory experiments were conducted and revealed particular effects of distinct algal species. The survival rate of artificially spawned eggs on algal substrates and control substrates was compared. Whereas filamentous forms of the green alga Ulva intestinalis induced no immediate effect, significantly higher egg mortality was documented in experiments with the filamentous brown alga Pylaiella littoralis.
- Considering the ecological and economical importance of herring and other coastal spawners on the one hand and the persisting and increasing effects of eutrophication and climate change on the other hand, the results of our study clearly underpin the necessity to increase global efforts to reduce nutrient loads in coastal waters.
20.
肠艾美耳球虫(Eimeria intestinalis)小配子体及小配子的发育均在宿主细胞的带虫空泡内进行,带虫空泡内含有较多的泡内小管以及由小配子体逸出的线粒体和基质小体。多核小配子体是由最初的单核小配子体发育而成。小配子的形成首先是中心粒转变成鞭毛的基粒,此后鞭毛和顶体与小配子体成切线方式长入带虫空泡;几个小线粒体融合成一大线粒体,嵌于核前方一侧,与核一起突入带虫空泡。成熟的小配子体长约6.5μm,有两根鞭毛。鞭毛的横断面为9+2的微管结构。体部由顶体、线粒体和核组成。由顶体的腹侧向后发出4～6根微管,其中只有2～3根延伸到体后部。 相似文献