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1.
Description of the digestive tract and feeding habits of the king angelfish and the Cortes angelfish 总被引:2,自引:0,他引:2
Morphologically, the digestive tracts of the king angelfish Holacunthus passer and the Cortes angelfish Pomacanthus zonipectus are similar, yet the king angelfish intestine is almost 30% longer than that of the Cortes angelfish. Both pomacanthids have a small mouth with villiform teeth, a short oesophagus, a well-defined stomach, and a terminal sac at the end of the digestive tract. The terminal sac, the acid pH in the stomach, and the long intestine may facilitate efficient use of seaweed nutrients. Stomach contents were analysed to determine diets and interspecific overlap. Seventy-one species were found in the stomachs of the king angelfish and 53 in the stomachs of the Cortes angelfish. Because of the wide range of species in their diets, both angelfish must be regarded as omnivorous. The most frequent foods were seaweed and sponges, but for the king angelfish, crustaceans were also important. A cluster analysis was done to determine whether the diets of these fish were similar by sex, size, or season. No similarities were found. Dietary overlap is high in relation to other pomacanthids. 相似文献
2.
Lars Orrhage 《Acta zoologica》1996,77(2):137-151
Abstract Earlier papers dealing with the anatomy of the hesionids and syllids were studied. Thereby it was found that information about the structure of the central nervous system was meagre. As a result, the anterior end appendages, especially the large, laterloventral ones of the Syllidae, have been differently interpreted. This prompted a re-investigation. The circum-oesophageal connectives, the brain commissures and the innervation of the alimentary canal and the cephalic appendages of a number of hesionid and syllid species were studied. The results, summarized in schematic diagrams, were compared with corresponding observations in other polychaete families. Among other things, it was concluded that not only the latero-ventral cephalic appendages of the hesionids but also those of the syllids are homologous with the palps of the nereids and of many other “errant” and “sedentary” families. 相似文献
3.
On the origin of the Hirudinea and the demise of the Oligochaeta 总被引:10,自引:0,他引:10
Martin P 《Proceedings. Biological sciences / The Royal Society》2001,268(1471):1089-1098
The phylogenetic relationships of the Clitellata were investigated with a data set of published and new complete 18S rRNA gene sequences of 51 species representing 41 families. Sequences were aligned on the basis of a secondary structure model and analysed with maximum parsimony and maximum likelihood. In contrast to the latter method, parsimony did not recover the monophyly of Clitellata. However, a close scrutiny of the data suggested a spurious attraction between some polychaetes and clitellates. As a rule, molecular trees are closely aligned with morphology-based phylogenies. Acanthobdellida and Euhirudinea were reconciled in their traditional Hirudinea clade and were included in the Oligochaeta with the Branchiobdellida via the Lumbriculidae as a possible link between the two assemblages. While the 18S gene yielded a meaningful historical signal for determining relationships within clitellates, the exact position of Hirudinea and Branchiobdellida within oligochaetes remained unresolved. The lack of phylogenetic signal is interpreted as evidence for a rapid radiation of these taxa. The placement of Clitellata within the Polychaeta remained unresolved. The biological reality of polytomies within annelids is suggested and supports the hypothesis of an extremely ancient radiation of polychaetes and emergence of clitellates. 相似文献
4.
The object of this study was to obtain the anatomic and morphometric data required for biomechanical analyses of the forelimb in dogs. Following the euthanasia of four healthy, adult, crossbred dogs, 44 muscles of the right forelimb were identified and meticulously removed. Morphometric data for all muscles were collected and physiologic cross-sectional areas (PCSA) and architectural indices (AI) were calculated. The coordinates of the origin and insertion of each muscle were determined using orthogonal, right-handed coordinate systems embedded in the scapula, humerus, and radius-ulna. The PCSA and AI were calculated for all the muscles and coordinates for the origins and insertions of these muscles were determined. Results provide the morphometric and anatomic data necessary for three-dimensional biomechanical studies of the forelimb in dogs. 相似文献
5.
The growth of Actinomyces spheroides 35 under different conditions and the biosynthesis of biomass, proteases and the antibiotic were studied with two types of growth medium: a control one and an optimized one. The rate of biomass accumulation was by 5--7 per cent higher on the latter medium than on the former one. The dynamics of accumulation was studied with novobiocin and proteases which hydrolyzed fibrin and casein. Fibrin hydrolyzing proteases were found to be synthesized under conditions that were unfavourable for the production of novobiocin. If the production of the antibiotic was supressed, the concentration of fibrinolytic proteases in the cultural broth increased almost proportionally. Such a relation has not been found for caseinolytic proteases. 相似文献
6.
《Saudi Journal of Biological Sciences》2019,26(8):1991-1994
ObjectiveTo investigate the efficacy of ropivacaine and bupivacaine in caesarean section and vital signs and the hemodynamics of the lying-in women.MethodsA total of 480 lying-in women who were admitted to this hospital for treatment between December 2017 and June 2018 were enrolled into this study as the subjects, which were divided into the experiment group and the control group, with 240 subjects in each group. In the experiment group, subjects received the local anesthesia by infusion of 1.5 mL ropivacaine (0.75%), while those in the control group also took the local anesthesia by infusion of 1.5 mL bupivacaine (0.75%). Thereafter, we observed the differences in the anesthetic efficiency, vital signs and hemodynamics of the lying-in women between two groups.ResultsThe excellent and good rates of the anesthesia in two groups were 92.1% and 87.9%, showing no obvious difference; in the experiment group, the average arterial pressures and systolic pressures at 5 min and 10 min after combined spinal and epidural analgesia (CSEA) were all elevated when comparing to the control group (all P < 0.05); in the experiment group, the onset time was obviously extended, while duration of sensory and motor block and the duration of motor block were all shorter than those in the control group (all P < 0.05). During anesthesia, the incidence rate of the adverse reactions in the control group was 2.50%, significantly higher than 0.83% in the experiment group (P < 0.05).ConclusionDespite that ropivacaine and bupivacaine are efficient in anesthesia in the CSEA in the caesarean section, ropivacaine is more recommended for little influence on the hemodynamics, shorter duration of sensory block and motor block and low incidence rate of adverse reactions, which are conducive to the recovery and also safe to the patients. 相似文献
7.
Mouse hepatocytes, quiescent and activated to proliferation after hepatectomy, were investigated using cytophotometry in the ultraviolet region of selective absorbtion of nucleic acids, and then were examined in the visible region of spectrum after cytochemical reaction for total protein. Some features of RNA and protein accumulation were revealed in the nucleus and cytoplasm of activated cells of different ploidy. The activation resulted in the reduction of histone content and in the increase in the nucleus: cytoplasm ratio in cells of all the ploidy classes. 相似文献
8.
A. A. J. Verhofstad R. E. Coupland T. R. Parker M. Goldstein 《Cell and tissue research》1985,242(2):233-243
Summary The pre- and postnatal development of the adrenal medulla was examined in the rat by immunohistochemistry and by assay of catecholamines. Immunohistochemistry involved the use of antibodies to noradrenaline (NA), adrenaline (A) and the biosynthesizing enzymes dopamine -hydroxylase (DBH) and phenylethanolamine N-methyltransferase (PNMT). Adrenal glands were obtained from animals from the 16th day of gestation to the 7th postnatal day at daily intervals, and at the 14th postnatal day, and from adult rats. Tissues were fixed in ice-cold, 4% paraformaldehyde, buffered at pH 7.3. Cryostat sections (7 m) were stained with the indirect immunofluorescence technique. Adrenals from the same developmental stages were assayed for the presence of DA (dopamine), NA and A by ion-pair reversed-phase liquid chromatography with electrochemical detection.In adult adrenals the majority of the medullary cells (approximately 80%) were highly immunoreactive to A and moderately immunoreactive to NA. They also showed immunoreactivity to both DBH and PNMT, i.e., they are synthesizing and storing A. The remaining cell clusters were only stained by antibodies to DBH and NA (NA-synthesizing and -storing cells). These findings correlate well with the relative concentrations of A and NA as determined by assay.Three developmental phases could be distinguished. In the first phase, the 16th and 17th prenatal day, medullary cells were only immunoreactive to DBH and NA, and only very small amounts of A as compared to NA were found. During the second period, from the 18th prenatal day to 2 or 3 days after birth, all medullary cells were immunoreactive to DBH, NA, PNMT and A, and during this phase the adrenaline concentration increased daily and became the predominant amine on the 20th day of gestation. Adrenaline represented 75% of total catecholamine on the 1st to 3rd day after birth. The third phase started at the 2nd or 3rd postnatal day and was characterized by the presence of an increasing number of medullary cells solely immunoreactive to DBH and NA, hence synthesizing and storing NA. The remaining cells were immunoreactive to DBH, NA, PNMT and A. Postnatally, the relative concentration of A continued to rise reaching 79% by the 4th postnatal day. These results indicate that initially the adrenal medullary cells are synthesizing and storing almost exclusively NA. Probably, adrenaline synthesis begins at the 16th–17th day of gestation and the cells are then capable of synthesizing and storing both NA and A (mixed cell type) with A synthesis and storage rapidly becoming predominant. Finally, after birth, separate NA-synthesizing and -storing cell types are formed and the so-called A cells stored predominantly (probably >90%) adrenaline with a small proportion of noradrenaline.In the medullary blastema and in the sympathetic ganglia of prenatal animals two cell types, only immunoreactive to DBH and NA, were observed. Presumably, these cells represent developing sympathetic neurons and extra-adrenal chromaffin cells; the latter cell type occasionally invades the adrenal gland. Thus, prospective medullary cells are able to synthesize and store NA before they have made contact with the cortical blastema but A-synthesizing cells are found only within the adrenal gland.Low but significant amounts of DA were found in the adrenal before birth and during the first two postnatal weeks but in the adult animal this accounted for less than 0.1% of total catecholamine.Preliminary reports of this study were made to the American Association of Anatomists (Anat. Rec. 196; 196A, 1980), the Dutch Anatomical Society (Acta Morphol. Neerl. Scand. 19; 330, 1981, and the XIIIth Acta Endocrinologica Congress (Acta Endocrinol. 97: Suppl. 243, 285, 1981) 相似文献
9.
Levels of Glycogen and Trehalose in Mycobacterium smegmatis and the Purification and Properties of the Glycogen Synthetase 总被引:1,自引:0,他引:1
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The levels of glycogen, free trehalose, and lipid-bound trehalose were compared in Mycobacterium smegmatis grown under various conditions of nitrogen limitation. In a mineral salts medium supplemented with yeast extract and containing fructose as the carbon source, the accumulation of glycogen increased dramatically as the NH(4)Cl content of the medium was lowered. However, levels of free trehalose remained relatively constant. Cells were grown in low nitrogen medium and were then shifted to medium containing high nitrogen. Under these conditions, there was a rapid accumulation of glycogen in low nitrogen, and this glycogen was rapidly depleted when cells were placed in high nitrogen medium. Again the concentration of free trehalose remained fairly constant. However, when cells were grown in low nitrogen medium with [(14)C]fructose and then transferred to high nitrogen medium with unlabeled fructose, the specific radioactivity (counts per minute per micromole) of the free trehalose fell immediately, indicating that it was being synthesized and turned over continually. On the other hand, the specific radioactivity of the glycogen and bound trehalose declined much more slowly, suggesting that these two compounds were not turning over as rapidly or were being synthesized at a much slower rate. Experiments on the incorporation of [(14)C]fructose into glycogen and trehalose indicated that cells in high nitrogen medium synthesized much less glycogen than those in low nitrogen. However, synthesis of both free trehalose and bound trehalose was the same in both cases. The specific enzymatic activities of the glycogen synthetase and the trehalose phosphate synthetase varied somewhat from one growth condition to another, but there was no correlation between enzymatic activity and the amount of glycogen or trehalose, suggesting that changes in glycogen levels were not due to increased synthetic capacity. The glycogen synthetase was purified about 35-fold and its properties were examined. This enzyme was specific for adenosine diphosphate glucose as the glucosyl donor. 相似文献
10.
目的了解凝固酶阴性葡萄球菌(CoNS)耐药基因和粘附基因的分布及其耐药性情况。方法收集45株凝固酶阴性葡萄球菌临床分离株,采用PCR检测其耐药基因mecA和粘附基因c弘知如B,并分析其耐药性。结果(1)凝固酶阴性葡萄球菌中mecA、cva、fn6pB的阳性率依次为86.7%(39/45)、11.1%(5/45)、71.1%(32/45)。(2)凝固酶阴性葡萄球菌中耐甲氧西林凝固酶阴性葡萄球菌(MRCoNS)的检出率为88.9%,对β-内酰胺类抗生素的耐药率都在80%以上,对利福平、左氧氟沙星、林可霉素的耐药率较低,未发现对万古霉素、利奈唑胺耐药菌株。结论CoNS中MRCoNS检出率很高,对常用抗生素耐药率高,且有一定的粘附能力,临床上应该根据药敏试验结果慎重及合理的使用抗生素。 相似文献
11.
Qualitative and quantitative aspects of the biosynthesis of ribonucleic acid and of protein in the liver and the lung of the Syrian golden hamster 总被引:2,自引:2,他引:0
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Hanspeter Witschi 《The Biochemical journal》1973,136(3):781-788
1. The incorporation of orotic acid and of uridine into total RNA was measured in vivo in liver and lung of the Syrian golden hamster. Specific activities of total acid-soluble UMP were measured in both organs. An estimation of the rate of RNA biosynthesis showed that hamster lung synthesizes RNA at about one-half of the rate of that of hamster liver. 2. The apparent K(m) and V(max.) values of a few enzymes involved in pyrimidine biosynthesis were measured in the 100000g supernatants of liver and lung. The apparent K(m) values were very similar in both organs. From the estimated V(max.,) it was concluded that hamster lung cells have less capacity to metabolize orotic acid than have liver cells. 3. A time-response and a dose-response study showed that actinomycin D inhibits pulmonary RNA synthesis as efficiently as hepatic RNA synthesis. 4. Protein synthesis, measured as the incorporation of leucine, was inhibited in both organs 30min after a dose of 2mg of cycloheximide/kg. The dose-response patterns were similar in both liver and lung 3h after cycloheximide. 5. It is concluded that RNA and protein synthesis in vivo in hamster lung are very similar to the corresponding reactions in liver. Alterations of RNA and protein synthesis by toxic agents can therefore be evaluated in lung with a similar approach to that used to study the pathological biochemistry of liver. 相似文献
12.
Luis Rajmil Noemí Robles Dolors Rodriguez-Arjona Marta Azuara Francisco Codina Hein Raat Ulrike Ravens-Sieberer 《PloS one》2014,9(12)
Background
The objectives of the study were to develop web-based Spanish and Catalan versions of the KIDSCREEN, and to compare scores and psychometric properties with the paper version.Methods
Internet and paper Spanish and Catalan versions of the KIDSCREEN-52 were included in a cross-sectional study in school-age children. Web-based and paper Spanish or Catalan versions of the KIDSCREEN-52 were administered to students aged 8 to 18 years from primary and secondary schools in Palafolls (Barcelona, Spain, n = 923). All students completed both web-based and paper versions during school time with an interval of at least 2 hours between administrations. The order of administration was randomized. The KIDSCREEN-52, the Strengths and Difficulties Questionnaire (SDQ), and sociodemographic variables were collected. Missing values, floor and ceiling effects, and internal consistency were compared between both versions, as well as mean score differences, level of agreement, and known groups and construct validity.Results
Participation rate was 77% (n = 715). Web-based and paper versions showed low percentage of missing values and similar high ceiling effect (range 0 to 44%). Mean score differences showed an effect size (ES) lower than 0.2 in all dimensions. Internal consistency ranged from 0.7 to 0.88, and degree of agreement was excellent (Intraclass correlation coefficient [ICC] range 0.75 to 0.87). Expected differences were seen by sex, age, socioeconomic status and mental health status.Conclusions
The web-based KIDSCREEN-52 showed similar scale score and reliability and validity than the paper version. It will incorporate the child population in the assessment of quality of life providing a more attractive format. 相似文献13.
T L Chebotareva 《Tsitologiia》1990,32(1):41-46
White rats were treated with a single administration of tetrapeptide tuftsin (Thr-Lys-Pro-Arg) in the dose 300 mcg/kg (b.w). Using interferometry, the protein content and concentration were assessed 15, 30 and 60 minutes after injection. The area of the neuron cytoplasm and nucleus were measured too. The nucleoplasmic balance and dispersion were calculated. Significant alterations in the protein contents and cellular area, nucleoplasmic balance and dispersion were detected in neurons of visual, sensomotor cortex and of n. accumbens. A possible interrelation is discussed between tuftsin action and the functional activity of neurons, between the level of their protein metabolism and establishment of emotional and motor response. 相似文献
14.
目的:探讨死胎的病因及终止妊娠的方式。方法:收集我院住院分娩的死胎病例23 例,对孕妇一般资料、死胎发生原因、终
止妊娠方式进行统计分析。结果:①死胎发生孕妇中,年龄>36 岁者最多,共8 例,占34.8%,孕周在28-36+6 周的孕妇数最多,共
10 例,占43.5%,初产妇17 例,占73.9%,有流产史孕妇9 例,占39.1%;②在所有病因中,脐带因素占比最大,共11 例,占47.8%,
其次为胎盘因素和母体因素,各5 例,各占21.7%,胎儿原因与不明原因各2 例,各占8.7%;③在对终止妊娠方式的选择上,施行
羊膜腔穿刺引产例数最多,共13 例,占56.5%,其次为剖宫产,共5 例,占21.7%,米索流产3 例,占13.0%,自娩患者2 例,占
8.7%。结论:脐带因素为造成死胎发生的主要原因,其次为胎盘因素及母体因素,应对孕妇进行全面的孕期检查及孕期健康教育,
以减少死胎的发生,并选择合适的终止妊娠方式以减轻孕妇痛苦。 相似文献
15.
Michal Fedoroňko Peter Temkovic Josef Königstein Vladimir Kováčik Igor Tvaroška 《Carbohydrate research》1980,87(1):35-50
In acid and alkaline media, glycolaldehyde (hydroxyacetaldehyde) exists in equilibrium with its enediol form, which is quantitatively oxidized to glyoxal by an excess of Methylene Blue. In acid and alkaline media, the enol form of methoxyacetaldehyde is formed. In alkaline medium, this enol is stable; in acid, it undergoes hydrolysis to glycolaldehyde. The kinetics of enolization of glycolaldehyde methoxyacetaldehyde were studied polarographically. The mechanisms of enolization of glycolaldehyde and acid hydrolysis of methoxyacetaldehyde were established both from kinetic data and from deuterium-incorporation data. The proposed mechanisms were confirmed by quantum-mechanical calculation of the charge distribution in the two compounds studied and their reaction intermediates. The glyoxal obtained in the oxidation was isolated as quinoxaline and analyzed by mass spectrometry. 相似文献
16.
M. H. Maxwell 《The Histochemical journal》1978,10(1):63-77
Synopsis Enzyme cytochemical studies have been carried out on eosinophils in the fowl and the duck. Peroxidase was found in all regions of the Golgi apparatus, the rough endoplasmic reticulum and the perinuclear cisternae of the early cells. In fowl eosinophil granules irregular deposits of peroxidase and arylsulphatase final reaction product were found, but the acid phosphatase deposits were even. In the duck in contrast, peroxidase was demonstrated in the external part of the granule only. Acid phosphatase and arylsulphatase were found in both the interna and the externa of the duck eosinophil granules. An ammoniacal silver nitrate reaction for the presence of the histone arginine was also studied. Silver deposits were found occupying all regions of the granules of eosinophils from both species of bird.The presence of the hydrolytic enzymes acid phosphatase and arylsulphatase in avian eosinophil granules supports the theory that these structures are lysosomal in nature and that they correspond with mammalian eosinophils in this respect. 相似文献
17.
对从HepG2细胞培养液中分离得到植基化和非糖基化PAI-1(1型纤溶酶原激活物抑制剂),以及从pYZHBI-66表达菌中纯化的非糖基化重组PAI-1的某些性质和功能进行比较,结果显示,糖基化PAI-1对tPA(组织型纤溶酶原激活物)有较强的抑制,能较显著地被蛋白质变性剂所激活,对热有较强的稳定性,糖基化与非糖基化PAI-1在pH2.5-9.0的范围内都相当稳定。纤维蛋白原和肝素能明显提高两者对tPA的抑制作用。 相似文献
18.
Rory Julien Michelland Valérie Monteils Sylvie Combes Laurent Cauquil Thierry Gidenne Laurence Fortun-Lamothe 《Anaerobe》2010,16(4):396-401
The archaeal community in the fermentative compartment and faeces of the cow and the rabbit were compared by analysis capillary electrophoresis single-stranded conformation polymorphism (CE-SSCP) profiles of 16S rRNA genes. Ruminal and faecal contents were sampled in five cows for three weeks. Hard and soft faeces were collected in 14 rabbits for three consecutive weeks and cæcal contents were sampled in the third week. The archaeal community differed according to the host species (ANOSIM-R = 0.53 and 0.72 respectively for the comparison of the fermentative compartments and faeces; P < 0.001) and to the location within the digestive tract of both species (ANOSIM-R = 0.37, 0.52 respectively for the cow and the rabbit; P < 0.001). In both species, the archaeal community of the digestive tract was stable over weeks and varied very little between individual animals. The structure (NS) and the richness index (9.9 ± 2.7, 10.1 ± 3.1 respectively, NS) of the archaeal community were similar for the cæcal content and the soft faeces which permitted to use the latter as a representative indicator. 相似文献
19.
Eighty-eight Long Evans/Turku rats were used in the study. The effect of the articulatory function on the mandibular condyle was observed histologically during normal growth, when the rat is changing its diet from milk to whole pellets as a part of weaning. Six animals each were killed at the age of 10, 15, 20, 25, 30, 35, 40 and 50 days for histological tissue processing. For further information, 30 animals were fed a soft diet (6 animals each were killed at the age of 25, 30, 35, 40 and 50 days), and 10 animals were fed hardened pellets (2 animals each were killed at the ages of 25, 30, 35, 40 and 50 days). An even and regular transition from mesenchymal cells via immature chondroblasts into mature chondroblasts and hypertrophied chondrocytes was found at 10, 15 and 20 days during normal growth and also at 25, 30, 35, 40 and 50 days when animals were fed a soft diet. This maturing process appeared to be disturbed at the age of 25, 30, 35 and 40 days in the superior aspect of the condyle in animals fed ordinary pellets. The density of the mesenchymal cell layer was decreased, and the amount of intercellular matrix seemed to be evaluated in mesenchymal and intermediate cell layers. These features were later manifest deeper in the cartilage as acellular regions and as cell clusters. The changes were similar but more severe when the animals were fed hardened pellets.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
20.
Ribosomal proteins from pure free and membrane-bound rat liver polysomes were analyzed with a highly resolutive two-dimensional gel electrophoresis technique, using sodium dodecyl sulfate in the second dimension. Three acidic proteins found in free polysomes were always absent from the membrane-bound polysomes. Their molecular weights were estimated to be 20 000, 19 500 and 18 500. When free ribosomes were dissociated into subunits, the three protein spots were still found in the 60S subunit pattern, but they were weaker than in polysomes. A possible involvement of these three proteins in the attachment of ribosomal structures to the membranes is proposed. 相似文献