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21.
The ascidian Ciona intestinalis is a model organism of developmental and evolutionary biology and may provide orucial clues concerning two fundamental matters, namely, how chordates originated from the putative deuterostome ancestor and how advanced chordates originated from the simplest chordates. In this paper, a whole-life-span culture of C. intestinalis was conducted. Fed with the diet combination of dry Spirulina, egg yolk, Dicrateria sp., edible yeast and weaning diet for shrimp, C. intestinalis grew up to average 59 mm and matured after 60 d cultivation. This culture process could be repeated using the artificially cultured mature ascidians as material. When the fertilized eggs were maintained under 10, 15, 20, 25 ℃, they hatched within 30 h, 22 h, 16 h and 12 h 50 min respectively experiencing cleavage, blastulation, gastrulation, neurulation, tailbud stage and tadpole stage, The tadpole larvae were characterized as typical but simplified chordates because of their dorsal nerve cord, notochord and primordial brain. After 8-24 h freely swimming, the tadpole larvae settled on the substrates and metamorphosized within 1-2 d into filter feeding sessile juvenile ascidians. In addition, unfertilized eggs were successfully dechorionated in filtered seawater containing 1% Tripsin, 0.25% EDTA at pH of 10.5 within 40 min. After fertilization, the dechorionated eggs developed well and hatched at normal hatching rate. In conclusion, this paper presented feasible methodology for rearing the tadpole larvae of C. intestinalis into sexual maturity under controlled conditions and detailed observations on the embryogenesis of the laboratory cultured ascidians, which will facilitate developmental and genetic research using this model system.  相似文献   
22.
This study was undertaken to determine the association of inflammatory biomarker, oxidative stress and antioxidant capacity marker with fetal haemoglobin (HbF) level among sickle cell trait and sickle cell disease (SCD) patients in Chattisgarh. The study group consisted of 51 SCD (SS) patients with painful episode, 49 SCD (SS) patients with steady state, 50 sickle cell trait (AS) and 50 controls. Malondialdehyde (MDA), CRP, total antioxidant power (FARP), total thiol and HbF levels were quantified. We found a significant positive (p < 0.0001) association between CRP and MDA levels and its inverse association with HbF level in SS patients. We also observed that antioxidant capacity had significantly positively (p < 0.0001) associated with HbF level. The protective effect of HbF was found, because the increase in HbF levels resulted in decrease in lipid peroxidation and inflammation in SCD patients. A decrease in the HbF level and its antioxidant capacity has been associated with the pathogenesis of SCD. These finding may explain the high level of HbF is ameliorating oxidative stress and inflammation in SCD patients.  相似文献   
23.
T. Pradeep 《Resonance》1999,4(1):53-62
In recent years, a number of systems have been shown to spontaneously assemble on appropriate solid surfaces to form films with thicknesses of molecular dimensions. The special techniques needed to prepare, characterise and study such monolayers are described. The potential applications of these systems as catalysts, sensors, electrooptic and other materials are summarized.  相似文献   
24.
Osteoarthritis of knee joints is a disease of old age in both sex. It is very common after the age of 40 years in elderly females or in postmenopausal phase of females. It is characterized by narrowing of space in joints due to inflammation. The exact mechanism of inflammation in this disease is not yet clear. Tumor necrosis factor alpha (TNF-α) may involve in onset of disease. The present study is being carried out in 130 female subject of age group 40–60 years suffering from osteoarthritis of knee joints and 50 normal healthy control female subjects. A correlation is made between TNF-α and estrogen and found significant inverse correlation (r<0.001), between TNF-α and estrogen hormone in osteoarthritic female patients as compared to normal healthy control female group.  相似文献   
25.
26.
Three species of Mansonioides vectors viz.,Ma. annulifera, Ma. uniformis andMa. indiana were found in Cherthala taluk, Kerala which is one of the endemic areas due toB. malayi. The immatures of Mansonioides thrive mainly in association with macrophytic hydrophytes such asP. stratiotes, S. molesta andE. crassipes in perennial habitats (ponds, channels/ canals etc.,) andI. miliaceae in seasonal habitats (fallow lands etc.) Breeding potential was higher (130.19) in clean ponds withP. stratiotes, compared to that of polluted ones (40.69). However, the polluted habitats infested with the same host plants were found to be the most productive forMa. annulifera, with an average daily adult emergence rate of 601/100 sq.m.). The clean habitats played a major role in the contribution ofMa. uniformis, whereS. molesta in the perennial habitats and I. miliaceae in the seasonal fallow lands were the favourable plants contributing a daily output of 12.5/100 sq.m and 221.81/100 sq.m. respectively.E. crassipes infested polluted habitats formed the major source forMa. indiana, the emergence rate being 13.89/100 sq.m. The perennial habitats supported mainly the breeding ofMa. annulifera (70.82%), whereas the seasonal habitats contributed the major chunk ofMa. uniformis (92.54%) andMa. indiana (71.43%). The bionomics of Mansonioides mosquitoes are thus shown to be greatly influenced by the community structure of hydrophytes and also the nature of breeding habitats.  相似文献   
27.
Lipid abnormalities remain to be a major cause of early mortality in patients with chronic renal failure (CRF). In present study, 114 (one hundred fourteen) CRF patients without any additional cause of dyslipidemia were divided into groups on the basis of etiologies of CRF. Blood samples from each group were analyzed for total cholesterol, triglyceride and HDL cholesterol along with blood urea nitrogen and serum creatinine. 25 healthy individuals without any obvious disease were taken as control. Patients from all the groups showed a marked hypertriglyceridemia of 232 (SD±77) mg/dl (P<0.001) as compared to control. Levels of HDL cholesterol were found to be significantly low 20 (±11) mg/dl (p<0.001) in all the groups. LDL cholesterol showed an increase 104 (±30) mg/dl as compared to control group which is not statistically significant. Present study reveals that, CRF patients show an uniform dyslipidemia irrespective of etiologies leading to CRF. This dyslipidemia is also independent of serum creatinine levels. Although, these lipid abnormalities may not solely cause mortality in CRF patients, they may act as modulators in accelerating atherogenesis which in turn cause early mortality in CRF patients.  相似文献   
28.
Einstein was in many ways like a detective on a mystery trail, though in his case he was on the trail of nature’s mysteries and not some murder mystery! And like all good detectives he had a style. It consisted of taking facts that he knew were correct and forcing nature into a situation that would contradict this established truth. In this process she would be forced to reveal some new truths. Einstein’s 1917 paper on the quantum theory of radiation is a classic example of this style that enabled him to predict the existence of stimulated radiation starting from an analysis of thermodynamic equilibrium between matter and radiation.  相似文献   
29.
There is ample evidence that vitamin status of an individual can have a profound influence on the resistance of Cancer. Pyridoxine is one of the water soluble vitamins playing an important role in various metabolic reactions. Aspartate aminotransferase and Alanine aminotransferase are pyridoxal phosphate requiring enzymes and their activities in erythrocytes have been used to assess the state of vitamin B6 nutrition in man. We report here the erythrocyte transaminase levels in controls and patients with early and advanced cancer of breast. Thein vitro study of vitamin B6 shows a marked difference in the per cent stimulation in patients as compared to the controls on addition of pyridoxal phosphate. The difference indicates a subclinical deficiency of vitamin B6. The possibility exists that the rapid progression of the disease could be due to lack of host resistance caused by the deficiency of vitamin B6. The possibility of an effective treatment response after enhancing the vitamin B6 status is being looked into.  相似文献   
30.
Vasant Natarajan 《Resonance》2005,10(12):148-162
Einstein was in many ways like a detective on a mystery trail, though in his case he was on the trail of nature’s mysteries and not some murder mystery! And like all good detectives he had a style. It consisted of taking facts that he knew were correct and forcing nature into a situation that would contradict this established truth. In this process she would be forced to reveal some new truths. Einstein’s 1917 paper on the quantum theory of radiation is a classic example of this style that enabled him to predict the existence of stimulated radiation starting from an analysis of thermodynamic equilibrium between matter and radiation.  相似文献   
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