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1.
水稻株高上位性效应和QE互作效应的QTL遗传研究 总被引:3,自引:0,他引:3
利用基因混合模型的QTL定位方法研究了由籼稻品种IR64和粳稻品种Azucena杂交衍生的DH群体在4个环境中的QTL上位性效应和环境互作效应,结果表明,上位性是数量性状的重要遗传基础,并揭示了上位性的几个重要特点,所有的QTL都参与了上位性效应的形成,64%的QTL还具有本身的加性效应,因此传统方法对QTL加性效应的估算会由于上位性的影响而有偏,其他36%的QTL没有本身的加性效应,却参与了48%的上位性互作用,这些位点可能通过诱发和修饰其他位点而起作用,上位性的特点还包括,经常发现了一个QTL与多个QTL发生互作;大效应的QTL也参与上位性互作;上位性互作受环境影响,QTL与环境的互效应比QTL的主效应更多地被检测到,表明数量性状基因的表达易受环境影响。 相似文献
2.
We extracted from L. biflexa patoc a fraction F, reacting in hemagglutination and ring tests with sera prepared against more than ten different serogroups. This fraction contains mainly a polysaccharide (65 per cent), the role of which was clearly demonstrated in the precipitation reaction with homologous antisera, through periodic oxidation; it also contains lipids (20 per cent) and proteins (10 per cent). We isolated from this fraction F, by Biogel column chromatography, 2 distinct antigens, one, F2, carrying the patoc-type specificity, the other, F 1B, a group specificity shared by many leptospira. These antigens differ not only immunogically, but also in their chemical composition. The type-specific antigen F2 contains mainly a polysaccharide composed of arabinose and glucosamine (possibly an immunodominant sugar). As for the group-specific fraction F 1B, its composition is more complex since lipids and proteins are also found with the polysaccharide. This antigen could therefore be a lipoglycoprotein. 相似文献
3.
Lactic acid production by rat retina in a medium containing phosphate was studied chemically. One half as much lactic acid was found as in a medium containing bicarbonate. In our experience the rate of respiration in a phosphate medium was sensitive to oxygen tension, for it was 38 per cent lower at 10 per cent and 51 per cent lower at 5 per cent oxygen than at 100 per cent oxygen. Previously Laser had reported no decrease in respiration at 5 per cent oxygen in phosphate medium. In phosphate medium, when the oxygen tension was varied, respiration and glycolysis bore a reciprocal relationship to each other. In bicarbonate medium, when the oxygen tension was lowered from 95 per cent to 5 per cent there was no significant change in the respiration, but glycolysis was increased nearly to the anaerobic level. This agrees with the earlier experiment of Laser in bicarbonate medium and adds support to his conclusion that the rate of glycolysis is controlled by oxygen tension rather than by the rate of respiration, under the conditions of the experiment. 相似文献
4.
《Biodemography and social biology》2013,59(3-4):176-186
Abstract The objectives of this study were to determine current usage of amniocentesis by women of advanced maternal age in a southwestern Ohio county and to determine potential usage levels by surveying women not utilizing the procedure to understand their reasons. For women age 35 and older giving birth in Hamilton County, Ohio, the estimated percentage using amniocentesis was 3.9 in 1978, 7.6 in 1979, and 13.3 in 1980. Approximately comparable statewide utilization rates were 7.0, 11.5, and 17.2 respectively. A telephone survey during the summer of 1980 of 81 Hamilton County women age 35 and older recently giving birth to a normal baby found four main reasons why they did not utilize amniocentesis: (1) they did not feel at an increased risk (29.6 per cent); (2) they had never heard of the test (24.7 per cent); (3) they were opposed to abortion (21.0 per cent); and (4) no one suggested they have the test done (19.8 per cent). Their physicians reported that 81 per cent of these women had received prenatal counseling. Thus, of those counseled, over two‐thirds apparently missed at least one essential message of the counseling they were presumably provided. These findings, coupled with 47.7 per cent of women who knew about amniocentesis saying they would most likely use it if they became pregnant again and their physician recommended it, indicate that utilization of prenatal diagnosis by at least 50 per cent of women age 35 and older is likely with greater public education and greater support of the procedure by obstetricians. 相似文献
5.
GILL J. J. B.; JONES B. M. G.; MARCHANT C. J.; MCLEISH J.; OCKENDON D. J. 《Annals of botany》1972,36(1):31-47
The chromosome numbers of 889 plants from 222 British populationsof Ranunculus ficaria were counted. 66.1 per cent of the populationscontained diploids (49.1 per cent of plants), 4.1 per cent containedtriploids (5.5 per cent of plants) and 43.2 per cent tetraploids(45.4 per cent of plants); 13.1 per cent of the populationscontained two or more polyplotypes. At the fruiting stage, tetraploidplants can be reliably distinguished from diploids by the presenceof axillary bulbils in the tetraploids and their absence inthe diploids. The production of well-developed heads of achenes,which is more characteristic of the diploids than of the tetraploids,is a less reliable character. Diploid plants are widespreadthroughout the British Isles but tetraploids are more commonin the east than in the west; 17.6 per cent of the diploid plantshad B-chromosomes and these plants were virtually confined tosouthern England and the Midlands. The occurrence of triploidsand of mixed populations of diploids and tetraploids are bothshown to be more common than previously supposed. 相似文献
6.
Alfred F. Goggio 《The Western journal of medicine》1959,90(2):151-154
The results of three independent surveys concerned with rheumatic fever and heart disease in students at the University of California were assembled and found to be in close agreement. A full 2 per cent of all students believed they had had rheumatic fever; and several times that proportion gave a history of one of the rheumatic manifestations. Only 0.25 per cent had demonstrable rheumatic heart disease and 0.1 per cent had congenital heart disease.Physiologic murmurs may occur in 3 per cent or more of students entering college.Penicillin prophylaxis is important in persons with rheumatic heart disease, but it is important not to put a label of rheumatic heart disease on persons who think they have had rheumatic fever but who have no demonstrable heart disease. Long term penicillin prophylaxis or other long term prophylactic procedures directed against rheumatic fever are not indicated unless the diagnostic criteria for rheumatic fever are clearly met or unless rheumatic heart involvement is definitely present. 相似文献
7.
Jack Lieberman 《The Western journal of medicine》1960,92(1):11-12
Seventy-six digital and periungual warts in 40 patients were treated topically with cantharidin, a potent blistering agent. The material, dissolved in equal parts of acetone and collodion, was applied directly to the warts. Occlusion facilitated blistering. No pretreatment was required. The warts were re-treated at weekly intervals until clinically cured.Fifty-six per cent of digital warts and 33 per cent of periungual warts cleared after a single application of cantharidin. Few required more than three treatments. Observation was continued for more than six months in more than half of the cases. Cure was lasting in about 70 per cent of the cases in which the long term result was known.Cantharidin ranks with liquid nitrogen in effectiveness, but it is painless to apply and does not cause scarring. For these reasons it is especially useful in children.The main disadvantage is pain and tenderness at the treated site for two to four days in some patients. This can be avoided by careful application of the drug. Occasionally new warts appear at the edge of the cantharidin blister. They are best treated by curettage and desiccation. 相似文献
8.
JACOBS AH 《California medicine》1957,86(1):8-10
A review of the literature on the natural history of strawberry hemangiomas revealed over-whelming evidence of the satisfactory spontaneous involution of over 95 per cent of these lesions without the scarring and danger of other sequelae inherent in the various forms of treatment. In a study of 105 strawberry nevi observed for more than one year, 97 per cent of the lesions had either completely disappeared or were regressing satisfactorily.A cross-section study of 1,735 consecutively examined children in routine pediatric practice showed hemangiomas to be present in 10.1 per cent of all infants from birth to one year of age but that this incidence drops to 1.5 per cent in children over five years of age, confirming the fact of spontaneous involution. 相似文献
9.
Summary A sandy loam (pH 6.5) was incubated at 28°C at static moisture levels, ranging from 10 per cent saturation to 133 per cent saturation (waterlogging), for 6 and 12 weeks; other samples covering the same moisture range were first incubated for 6 weeks, and after changing all moisture levels to 50 per cent saturation were incubated for a further 6 weeks.With increasing static soil moisture level during incubation there was a slight reduction in Morgan-extractable phosphate up to 70 per cent saturation, but thereafter, due to anaerobic effects, there were considerable increases in extractable phosphate with increasing moisture level.With changing moisture level during incubation the effects of anaerobiosis became apparent where original moisture level was greater than 50 per cent saturation; extractable phosphate was reduced to levels lower than those occurring where the soil was maintained continuously at 50 per cent saturation. The extent of reduction in extractable phosphate increased with original soil saturation level. 相似文献
10.
Riskin DK Bergou A Breuer KS Swartz SM 《Proceedings. Biological sciences / The Royal Society》2012,279(1740):2945-2950
Flying vertebrates change the shapes of their wings during the upstroke, thereby decreasing wing surface area and bringing the wings closer to the body than during downstroke. These, and other wing deformations, might reduce the inertial cost of the upstroke compared with what it would be if the wings remained fully extended. However, wing deformations themselves entail energetic costs that could exceed any inertial energy savings. Using a model that incorporates detailed three-dimensional wing kinematics, we estimated the inertial cost of flapping flight for six bat species spanning a 40-fold range of body masses. We estimate that folding and unfolding comprises roughly 44 per cent of the inertial cost, but that the total inertial cost is only approximately 65 per cent of what it would be if the wing remained extended and rigid throughout the wingbeat cycle. Folding and unfolding occurred mostly during the upstroke; hence, our model suggests inertial cost of the upstroke is not less than that of downstroke. The cost of accelerating the metacarpals and phalanges accounted for around 44 per cent of inertial costs, although those elements constitute only 12 per cent of wing weight. This highlights the energetic benefit afforded to bats by the decreased mineralization of the distal wing bones. 相似文献
11.
In a 29-month period, 151 of 373 deaths of California women occurring during or within 90 days of termination of pregnancy were studied jointly by the California Medical Association and the California State Department of Public Health. Twenty-two per cent of the deaths reviewed were considered unavoidable. In 74 per cent, one or more avoidable factors were identified. Avoidable factors could not be identified in 4 per cent of the cases.Thirty-three per cent of the cases considered to have avoidable factors were attributed to be solely the responsibility of the attending physician. Inadequate hospital facilities were held responsible in less than 1 per cent of deaths, while responsibility in 26 per cent of the deaths was laid directly to patient error or refusal. In 40 per cent of the avoidable deaths, more than one avoidable factor was identified.Nonobstetric conditions accounted for the greatest proportion of the deaths, followed by hemorrhage, toxemia of pregnancy, sepsis, abortion and ectopic pregnancy.The findings of this study compare closely with those of similar studies in other states, including Minnesota and Massachusetts. 相似文献
12.
Serum chloride and phosphate concentrations were measured in 79 hypercalcemic patients. The chloride values were higher (mean 106.7 mEq/l) and phosphate lower (mean 2.08 mg/100 ml) in the 53 hyperparathyroid patients, where as the chloride concentrations were lower (mean 99.3 mEq/l) and phosphate higher (mean 4.07 mg/100 ml) in the 26 patients with hypercalcemia from other causes. The chloride phosphate ratio ranged from 19 to 32 in the subjects with hypercalcemia from other causes with 90 per cent of values less than 30. In patients with primary hyperparathyroidism we found 96 per cent of the values more than 34. From our experience with chloride phosphate ratio it seems to us that this ratio is a very useful and simple preliminary test for distinguishing patients with primary hyperparathyroidism from patients with hypercalcemia from other causes, with normal renal functions. 相似文献
13.
The results published in the period from 1973 to 1983 entitled "Cytogenetic findings in acute myeloic leukemias" (M 1 to M 6 of FAB classification) were compiled. In 50-60 per cent of those patients affected with acute myeloic leukemia a deviating karyotype could be detected. With a markedly higher frequency chromosomes 8 and 21 will take part in aberrations, with translocations (8; 21) having the main share with about 30-40 per cent. More than half the male bearers of translocation exhibits a loss of the Y-chromosome, a third of female patients a loss of the X-chromosome. Trisomy 8 and 9 as well as monosomy 7 appear in about 20 per cent. These aberrations can also be found in all other leukemic and preleukemic processes. Patients with karyotypic abnormalities in all their cells will have the slightest average survival time and the worst appeal to therapy. The sole appearance of monosomy 7 or Ph1-chromosome respectively seems to be an unfavourable sign from a prognostic point of view. Children with acute myeloic leukemia will possess an aberrant karyotype more frequently than adults, but they have a longer average life, boys are more frequently affected by this. Acute promyelocytic leukemia can be characterized cytogenetically in 94 per cent of the cases by translocation (15; 17). However, distinct geographical differences can be observed here, the causes of which have not been elucidated. About 40 per cent of the patients with acute myelo-monocytic leukemia developed aberrations. Further investigations will have to show whether the chromosome 11 really took part in it somewhat more frequently than merely at random. Chromosome anomalies have not a visible influence on the course of the disease. In 30-40 per cent of patients with a rarely occurring acute monocytic leukemia, an abnormal karyotype could be found. There was an incidence of 47 per cent for a specific translocation (9; 11) or a similar variant respectively. Erythroleukemia is characterized by a high instability of chromosomes and karyotypical variability, particularly in erythrocyte precursors and by an average survival time of one months. Megakaryoblastic and eosinophilic leukemia are very rare kinds of acute leukemias. The small number of publications allows no general statement to be made concerning karyotypical changes. 相似文献
14.
Effect of Removal of a Part of the Root System on the Subsequent Growth of the Root and Shoot 总被引:3,自引:0,他引:3
Removal of up to 50 per cent. of the roots of barley and ryehas no effect on the growth-rate of the root which is the sameas in the intact plant. In contrast the growth-rate of the shootdecreases as more roots are removed. When more than 50 per cent.of the roots are removed, root growth declines but not so rapidlyas that of the shoot. Similar results are obtained by the removalof lateral roots of tomato but root growth begins to declinewhen 40 per cent. of the lateral roots are removed. The uptake of potassium by barley plants with proportions ofthe root system excised is closely proportional to the dry-matterincrease when the nutrient supply is not limiting. In conditionsof low nutrition the potassium uptake is less than the dry-matterincrease. 相似文献
15.
Alvin H. Jacobs 《The Western journal of medicine》1957,86(1):8-10
A review of the literature on the natural history of strawberry hemangiomas revealed over-whelming evidence of the satisfactory spontaneous involution of over 95 per cent of these lesions without the scarring and danger of other sequelae inherent in the various forms of treatment.In a study of 105 strawberry nevi observed for more than one year, 97 per cent of the lesions had either completely disappeared or were regressing satisfactorily.A cross-section study of 1,735 consecutively examined children in routine pediatric practice showed hemangiomas to be present in 10.1 per cent of all infants from birth to one year of age but that this incidence drops to 1.5 per cent in children over five years of age, confirming the fact of spontaneous involution. 相似文献
16.
C A Cunningham 《The British journal of physiological optics》1979,33(1):1-40
This is a survey of the causes of blindness recorded by three students of The City University during a six-week stay at NOOR Eye Institute in Kabul, Afghanistan. The nature of the sample used makes it unsuitable for direct comparison with surveys from other countries. Nevertheless, broad conclusions can be drawn. Severe eye disease is a considerable problem in Afghanistan, in common with other developing countries. The survey included all new patients seen in the outpatient clinic, blind to the extent of being unable to count fingers at more than three metres, in one eye or both. The sample of patients was examined by an ophthalmologist working with our team. A diagnosis was made and various social and demographic questions were asked with the help of an interpreter. In all, 473 patients were examined and included in our survey sample, a very high proportion of the new patients attending the clinic (40.46 per cent). The main causes of blindness were found to be cataract (31.12 per cent), corneal scarring (19.8 per cent), chorioretinal degenerations (6.79 per cent), glaucoma (6.65 per cent) and aphakia (5.52 per cent). Of the major causes of blindness, about forty per cent of the cases were considered remediable, and about thirty per cent could have been prevented. An outstanding difference between the causes of blindness in developed nations and those seen in Afghanistan was the amount of blindness caused by infection, especially in the younger age groups (up to 30 years). Cataract is a major cause of blindness in the older age groups of both societies. People suffering from ocular disease in Afghanistan wait until their sight is badly impaired or lost completely before seeking treatment. This results from a lack of knowledge of what could be done to conserve sight, the irreversible nature of many eye diseases, the distances involved in travelling to the clinic, and even a lack of knowledge of its existence. 相似文献
17.
K E Buckton 《International journal of radiation biology and related studies in physics, chemistry, and medicine》1976,29(5):475-488
The aberrations seen in chromosomes of human peripheral-blood lymphocytes, X-irradiated in vitro, have been analysed in three types of preparations, treated to give G-banding; R-banding; and G-banding followed by R-banding on the same cells. The data from cells subjected to both banding techniques reveals that 30 per cent of the sites of chromosome breakage are situated at he interfaces between dark- and - light-stained bands. The results of all the analyses show that approximately 30 per cent of all breaks were located in either the telomere (19-5 per cent) or centromere (11-3 per cent) regions. Chromosomes rich in R-band material were not preferentially damaged, but chromosomes 12, 15, and particularly 17, were involved in aberrations more frequently than would be expected on the basis of their length. No breaks were found on the Y chromosome in the 114 male cells analysed, but the X did not appear to be spared from damage either in the male cells analysed, but the X did not appear to be spared from damage either in the male cell or the 136 female cells analysed. G and/or R-banding enables a much more accurate analysis of aberrations than can be obtained from the use of conventional staining techniques, and with these methods, it is shown that the numbers of induced asymmetrical and symmetrical exchanges are similar. 相似文献
18.
Jerome Harold Kay Harold K. Tsuji John V. Redington Taro Yokoyama 《The Western journal of medicine》1967,107(4):311-314
Sixty-four patients with pure mitral insufficiency were operated upon. Thirty of them had torn chordae tendineae. It was possible to repair the mitral valve in 57 patients and there were five operative deaths. One patient had a femoral artery embolus and another had a cerebral embolus. The incidence of peripheral embolization was 4 per cent compared with 40 per cent reported for ball valve replacement.Forty-eight of the 57 patients with repair (84 per cent) were living and well with at most a grade II/VI apical systolic murmur up to seven and a half years after operation. There has been no evidence of recurrence in these patients.In approximately 90 per cent of patients with pure mitral insufficiency, repair should be performed. When feasible, repair is more satisfactory than valvular replacement, with not only excellent long-term results, but far less morbidity than is reported with ball valve replacement. 相似文献
19.
Günter Kiefer Renate Kiefer Prof. Dr. Walter Sandritter 《Histochemistry and cell biology》1968,14(1):65-71
Summary DNA was removed from various tissues by histochemical acetylation of amino groups in proteins using pure acetic anhydride, as demonstrated by cytophotometric (UV, Feulgen, gallocyanin chromalum) and biochemical techniques. Since new phosphate groups were simultaneously exposed, the intensity of methylene blue staining was increased in spite of the nucleic acid release. Under conditions where no extraction occurs the staining intensity increases for more than 30 per cent. On the other hand, the staining intensity of gallocyanin chromalum kept constant. As it had been demonstrated previously, that gallocyanin chromalum binds to about 86 per cent of the DNA phosphate groups, it was concluded that this dye binds to a higher percentage of phosphate groups than do the usual basic dyes. Since it is not possible under the conditions used to make all nucleic acid phosphate groups available for basic dye binding by blocking the amino groups of proteins it can be assumed that not only electrostatic, but also spatial and steric relationships influence the binding capacity of basic dyes to the phosphate groups of nucleoproteins.Supported by a grant from the Deutsche Forschungsgemeinschaft, Bad Godesberg, Germany. 相似文献
20.
At present, according to the unanimously accepted data, cholecystoses are noninflammatory, nonlithiasic, gallbladder diseases. However the authors' experience has proved that the inflammatory process is much more frequent than it is believed and often associated also with lithiasis, a fact which, in the authors' opinion, would justify a reconsideration of this group of diseases. This study, based on histopathologic examination, was carried out in 1,630 gallbladder specimens, surgically removed. Out of these, 278 (17.05 per cent) were identified as cholecystoses; 156 out of them were cholesteroloses and 122 diverticular diseases of the gallbladder. Inflammation as a well defined morphologic process was found in 104 cases (66.67 per cent) of cholesterolosis and in 119 cases (97.54 per cent) of diverticular disease, therefore 80.21 per cent of the cases of cholecystosis examined were associated with inflammation. As regards lithiasis, it was present in 131 of the cases (46.76 per cent). The inflammatory process presented a chronic aspect with no other particular morphologic characteristics. By correlating the histopathologic data with the clinical evolutive ones, it was observed that the presence of inflammation corresponded with a clinical evolution of the disease of about three years. The authors believed that the group of cholecystoses should be reconsidered bearing in mind that inflammation is present in most of the cases and in almost half of them it is associated with lithiases. Under these conditions the sphere of chronic nonlithiasic, noninflammatory gallbladder diseases becomes considerably reduced today. 相似文献