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1.
Leptocephalus eel larvae will feed in aquaria   总被引:1,自引:0,他引:1  
Synopsis Premetamorphosing larvae of Muraenesox cinereus (Muraenesocidae) and Conger myriaster (Congridae), caught and kept alive in aquaria, repeatedly bit pieces out of a lump of squid paste. By coloring the paste with Brilliant Red, ingestion and defecation were clearly seen through the transparent gut. The paste is not their natural food, but nevertheless a possible food item for rearing eels from eggs; most previous efforts have failed inasmuch as the larvae have starved.  相似文献   
2.
Secretin modulation of behavioral and physiological functions in the rat   总被引:2,自引:0,他引:2  
The effect of secretin on behavioral and physiological functions in the rat was investigated. Secretin injected intracerebroventricularly (ICV) significantly increased defecation and decreased novel-object approaches in rats. The peptide showed no significant effects on stereotypic behavior (gnawing, grooming and rearing), open-field locomotor activity however was significantly decreased, an effect that was probably due to a decreased propensity for the rats to initiate locomotor responses. In addition, secretin showed significant effects on respiration rate in anesthetized rats. When the peptide was injected in the lateral ventricle a decrease in respiration rate occurred, but when the brain was perfused from the lateral ventricle to the cisterna magna increases in respiration rate occurred. These data, combined with the facts that secretin and secretin receptors have been identified in the brain indicate that secretin may play a neurotransmitter or neuroregulator role in the central nervous system.  相似文献   
3.
Seed dispersal has become an important issue in plant ecology and restoration management. In this paper we examined dung germinating seed content and seed deposition patterns of horses (Shetland and Konik breeds) and Scottish Highland cattle grazing two coastal dune nature reserves. Two times 2.5 l of fresh dung from each type of herbivore were collected during seven sessions in the main fruiting season. Dung samples were placed under greenhouse conditions after drying and cooling. Animal defecation patterns were derived from a study of herbivore activities during 6 h observation sessions 8 times a month. One hundred and seventeen plant species i.e. 27% of all species occurring in the study area, were recorded as seedlings emerging from the dung samples. The most abundantly and frequently recorded plant species were Urtica dioica, Juncus spp. and different species of Poaceae and Caryophyllaceae. In general seedling density is high (1158 seedlings/dung sample). Seedling density and species richness were further analysed in order to detect temporal variability and possible animal and site related characteristics. Dung deposition patterns reflect a non-random use of habitats and hence a non-random seed deposition among habitats. Calculated seed deposition per square meter ranged from a few (<10 germinating seeds) to more than 100 in the most frequently selected habitats. From the herbivores’ selective habitat use and their estimated mean retention time we can further assume their ability for inter-habitat endozoochorous seed dispersal. This characteristic of large herbivores is further discussed in the light of nature management and restoration.Indra Lamoot is an aspirant of FWO-Flanders.  相似文献   
4.
Wecompared the effects of two mechanisms of fruit processing (defecationversus regurgitation) on seed germination andestablishmentin a mistletoe-bird system (Tristerix aphyllusMimus thenca). Despite regurgitation being more frequentlyobserved than defecation, radicle of defecated seeds grew longer than that ofregurgitated ones. In this fruit-seed disperser interaction, we demonstrate theimportance of different mechanisms of fruit processing for cactus infectionefficiency by the mistletoe.  相似文献   
5.
Evolution of the ischial spine and of the pelvic floor in the Hominoidea   总被引:1,自引:0,他引:1  
Study of the pelvis in 143 different mammals reveals that in quadrupeds the ischial spines are barely noticeable and are located posteriorly near the sacrum. In humans, the ischial spines are prominent and more anteriorly located. As a consequence of their position and size, the ischial spines in humans become an obstacle to parturition. Herein a theory is proposed to account for what appears to be an incongruous development and orientation of the ischial spines in humans. The pelvic diaphragm is a vertical pelvic "wall" in tailed mammals and is composed of muscles involved mostly with the motion of the tail. In humans, the muscles of the pelvic diaphragm have a very different anatomical orientation. They form a horizontal pelvic "floor," and their functions are first to support the abdominopelvic organs and resist intra-abdominal pressure that is exerted from above, and second, as levator ani, to control the anal sphincter. In humans the muscles and fascias of the pelvic diaphragm are inserted on the ischial spines either directly or indirectly through the sacrospinous ligament and the tendinous arch of the pelvic fascia. The result is a medial pull on the ischial spines to produce a more rigid and narrower pelvic floor. An inconstant ossification center for the ischial spines make them more prominent. The backward tilt of the sacrum placed the bispinal line in a diameter position. Pongids and even fossil hominids occupy an intermediate position between tailed mammals and Homo sapiens. The present form of the pelvis in Homo sapiens may be determined by a significant genetic component but may also be partly acquired during childhood and adolescence.  相似文献   
6.
摘要 目的:比较腔镜下Soave根治术与开腹改良Soave术治疗长段型先天性巨结肠(HD)患儿的疗效,观察两种术式对应激反应和控便功能的影响。方法:选取我院2017年4月~2020年9月期间收治的长段型HD患儿88例,根据手术方式的不同分为开腹组和微创组,例数分别为43例和45例。对比两组围术期指标、应激反应指标、控便功能和并发症发生情况。结果:微创组的术中失血量少于开腹组,手术时间、胃肠功能恢复时间、禁食时间、住院时间短于开腹组(P<0.05),两组肠管切除长度组间对比无统计学差异(P>0.05)。两组患儿术后1 d心率(HR)、平均动脉压(MAP)较术前升高,血氧饱和度(SpO2)较术前下降,但微创组HR、MAP低于开腹组,SpO2高于开腹组(P<0.05)。两组患儿术后1年大便性状、排便次数、污粪、需要治疗(灌肠、药物、尿布)评分及Heikkinen总分均较术前升高,且微创组高于开腹组(P<0.05)。微创组的近期并发症总发生率和远期并发症总发生率均低于开腹组(P<0.05)。结论:与开腹改良Soave术相比,采用腔镜下Soave根治术治疗长段型HD患儿可缩短手术时间、禁食时间、住院时间、胃肠功能恢复时间,减少手术创伤,减轻机体应激反应,改善患儿控便功能,同时还可降低并发症发生率,效果较好。  相似文献   
7.
目的:探讨生物反馈训练辅助治疗梗阻性便秘患者对粪便性状、排便时间与排便频度的影响。方法:选取我院收治的90例梗阻性便秘患者,根据随机数字表法分为3组,A组接受常规治疗,B组于常规治疗基础上进行固定式生物反馈训练(FBF),C组于常规治疗基础上进行自适应式生物反馈训练(ABF),比较3组治疗前后肛直肠功能、粪便性状、排便时间、排便频度和临床疗效。结果:治疗后,直肠肛门压力梯度:A组B组C组(P0.05),矛盾性收缩率:A组B组C组(P0.05),B组与C组肛管静息压、直肠肛门抑制反射阈值显著小于A组(P0.05),且肛管松弛率显著大于A组(P0.05);C组粪便性状4~7型占比明显高于其余两组(P0.05),且B组4~7型占比明显高于A组(P0.05);排便时间:A组B组C组(P0.05),排便频度:A组B组C组(P0.05);C组总有效率显著高于A组与B组(P0.05)。结论:生物反馈训练尤其是ABF可有效改善梗阻性便秘患者肛直肠功能,在改善粪便性状、缩短排便时间、增加排便频度上具有明显优势,可获得更好的临床疗效。  相似文献   
8.
The role of green sea urchin Strongylocentrotus droebachiensis as a source of fecal particulate organic matter (POM) for the benthic nearshore ecosystems has been studied over a 3.5-month period. Three macroalgae were tested as food sources: Alaria esculenta, Laminaria longicruris and Ulvaria obscura. Urchins were fed ad libitum with either a single alga species or a mixture of all three algae. Consumption and defecation rates were determined as well as the feces/alga ratio in term of biomass and biochemical composition. Consumption rate increased exponentially with urchin size and also varied with alga species. In the single alga trial, consumption rate was higher for both brown algae (Laminaria and Alaria) compared to Ulvaria. Urchins feeding on the mixture of algae maintained their total ingestion rate (sum of the three algae) at the same level to those feeding on a single alga diet. The mixed algae trial showed that urchins clearly preferred Laminaria (72% of total ingestion) over Alaria (22%) and Ulvaria (6%). The defecation rate was tightly correlated with the food consumption rate and thus increased with urchin size. On average, 75% of the ingested algal biomass was released as fecal POM. The percentage of food defecated changed with alga species, with the highest value for Alaria (81%) and the lowest for Laminaria (67%). The percentage of food defecated by urchins feeding on the mixture of algae was generally comparable to those feeding on single alga diet. Biochemical composition (in soluble carbohydrates, proteins and lipids) of urchin fecal POM reflected that of the algae content. From 40% to 80% of macronutrients in algal food persisted in fecal matter. This proportion varied with the alga species and macronutrient considered. This study shows that the green sea urchin plays a significant role in the production of POM within nearshore benthic ecosystems, and it is a potentially nutritious food source for detritivores.  相似文献   
9.
The present study shows that α-MSH facilitates the acquisition and delays the extinction of a Passive Avoidance Response (PAR) in the hypox animals. MSH exacerbates PA-induced defecation in both hypox and sham-hypox animals. Hypox and sham-hypox animals treated with MSH do not differ on PAR or on PA-induced defecation. Melatonin, on the other hand, has no significant effect on PAR in hypox rats, but retards acquisition and facilitates extinction of the PAR in sham-hypox rats. Melatonin also inhibits PA-induced defecation in sham-hypox rats. Sham-hypox and hypox rats treated with Melatonin do not differ on PAR learning, retention (Extinction) and PA-induced defecation. MSH and Melatonin also seem to have opposite effects on plasma 11-OHCS levels measured at the end of PAR extinction. MSH increases plasma 11-OHCS in hypox rats, whereas Melatonin decreases plasma 11-OHCS in sham-hypox rats. Melatonin does not lower further the very low level of plasma 11-OHCS in hypox rats.  相似文献   
10.
摘要 目的:探讨直肠癌切除术患者永久性与临时性造口术后生活质量变化,并分析其生活质量与排便症状的相关性。方法:纳入我院2017年4月~2020年4月收治的直肠癌切除术患者110例,所有纳入者均行造口术。根据造口方式,分成永久性造口组(简称永久组,n=41)、临时性造口组(简称临时组,n=69)。记录两组造口并发症发生率,分别在患者术后1、3、6个月,采用简明生活质量量表(SF-36)评估其生活质量,采用排便症状量表评估患者排便症状的变化。经Pearson线性相关分析患者生活质量评分与排便症状评分的相关性。结果:临时组造口并发症发生率(8.90%)与永久组(12.20%)比较无差异(P>0.05)。两组术后3、6个月SF-36各维度评分均高于术后1个月,术后6个月各评分高于术后3个月,且临时组术后3个月SF-36各维度评分高于永久组(P<0.05),但两组术后6个月各评分比较无差异(P>0.05)。两组术后3、6个月大便症状各评分均低于术后1个月,术后6个月的排便急迫感、排便费力、里急后重评分及总分低于术后3个月,且临时组术后3个月的排便急迫感、排便费力、里急后重评分及总分低于永久组(P<0.05),但两组术后6个月排便症状各评分比较未见差异(P>0.05)。Pearson线性相关分析显示,排便症状总分与机体疼痛、躯体功能、躯体角色受限、情感角色受限、心理健康、社会功能、总体健康评分呈负相关(P<0.05)。结论:直肠癌切除术患者临时性造口能够进一步促进术后3个月生活质量、排便功能的改善,在术后6个月,永久性造口患者的生活质量、排便功能基本达到临时性造口患者的状态,且排便功能与生活质量具有相关性。  相似文献   
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