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1.
Asian soybean rust (ASR), caused by Phakopsora pachyrhizi, is one of the most important diseases on soybean. At the moment, ASR is managed mainly with fungicides due to the absence of commercial cultivars with resistance to this disease. This study evaluated the effects of acibenzolar‐Smethyl (ASM), jasmonic acid (JA), potassium silicate (PS) and calcium silicate (CS) on soybean resistance to ASR. The ASM, JA and PS were sprayed to leaves 24 h prior to inoculation with P. pachyrhizi. The CS was amended to the soil. The incubation period (time from the inoculation until symptoms development) was longer for plants growing in soil amended with CS or sprayed with ASM in comparison with plants sprayed with water (control). Plants sprayed with ASM had longer latent period (time from the inoculation until signs appearance) in comparison with the control plants. Plants sprayed with PS showed fewer uredia per cm² of leaf in relation to the control plants. The ASM and PS were the most effective treatments in reducing the ASR symptoms in contrast to the JA and CS treatments. The JA served as an inducer of susceptibility to ASR.  相似文献   

2.
One hundred and twelve nasal polyps received along with full history from three different hospitals of Kanyakumari district of Tamil Nadu during the period 1983–1987 were found positive for rhinosporidiosis on histopathological examination. Among the four taluks (countries) the majority of the cases (41.1 per cent) came from Agastheeswaram, followed by Kalkulam (28.6 per cent), Thovalai (17.0 per cent) and Vilavancode (13.3 per cent). The 11–20 years age group found to be highly susceptible (60 per cent). There was no sex prepondence in contracting the disease as the cases were evenly distributed between both sexes. These findings exhibited the endemic nature of the disease in Kanyakumari district.Unreported cases to an extent of 9 to 40 per cent were encountered during the ENT disease diagnostic camps conducted in nine high incidence villages. Further 8 more cases were detected in addition to cases attended in the hospitals and ENT camps when a complete enumeration of cases was undertaken in Pallam village. Thus the actual number of cases found in the district need a stratified random sampling.  相似文献   

3.
The incidence of anencephaly at the Los Angeles County General Hospital during the period of July, 1948 through June, 1958 was 0.049 per cent. Worldwide the range of reported incidence is 0.012 per cent to 0.671 per cent.In this study 65 per cent of the total number of anencephalics delivered were females, a predominance agreeing with reports by other investigators.Polyhydramnios appeared in 38 per cent of the anencephalic pregnancies of this study, while 15 per cent of the deliveries were complicated by placenta praevia.A significant number (48 per cent) of the multiparae gave a history of previous stillbirths or abortions.The present study does not support observations by other investigators which indicated an increase in anencephalic births during the winter months.Evidence from stillbirth statistics would seem to indicate that anencephaly is primarily a genetically induced phenomenon. Further evaluation and analysis of the predominance of females in anencephalic stillbirths and abortions is suggested, in order to study whether the observed secondary or birth sex ratio (in which males predominate) is, in fact, due to genetic effect.  相似文献   

4.
A statistical survey was made of all the cases of poliomyelitis occurring in all of Los Angeles County during the three years of 1949, 1950 and 1951 in an attempt to determine the effect of operations on the nose and throat on the incidence of poliomyelitis. Tonsillectomy and adenoidectomy were the only operations noted with any degree of frequency. Yet, in the total of 3,601 cases of poliomyelitis that occurred in this three-year period there were only 20 (0.55 per cent) in which the patient had had recent tonsillectomy and adenoidectomy. The incidence of this disease in patients who had had tonsillectomy and adenoidectomy was compared with the "expected" incidence as determined from the incidence in other patients, in the same age group. There was no significant difference between actual and expected incidence even during the summer months when most cases of poliomyelitis occurred. The same was true with regard to recently tonsillectomized patients in the epidemic months of July through October. In a separate survey of 675 patients with poliomyelitis, it was noted that only 30 per cent ever had had tonsillectomy or adenoidectomy. Inasmuch as it is estimated that one of every three persons in the general young population nowadays has had tonsillectomy and adenoidectomy, this figure is no more or less than could be expected.  相似文献   

5.
A review was made of the cases of 93 patients with burns covering more than 20 per cent of the body surface who were treated at the San Francisco City and County Hospital, University of California Service, between 1943 and 1956. The mortality rate increased from 40 per cent during 1943-1947 to 69 per cent during 1952-1956. A significant change in survival time was noted: During 1943-1947, 69 per cent of the deaths occurred within 48 hours of admission; during 1952-1956, only 19 per cent of the deaths occurred within the first 48 hours. In the period 1943-1947 the majority of deaths resulted from shock in the immediate post-burn period; in the later years of the study the major cause of death was infection. No patient more than 50 years of age who had burns of more than 25 per cent of the body surface survived. Only one patient with burns involving more than 45 per cent survived. No patient who had a blood culture positive for bacteria survived. The use of antibiotics had no effect on the incidence of infection. Elderly patients, children and alcoholics were less able to resist the effects of infection. The lowest mortality rate was in the age group of 15 through 35 years.  相似文献   

6.
Summary Phytotoxins developed during heat-sterilization of soil were removed by 40 per cent of the fungi and ten per cent of the bacteria isolated from inoculated heat-sterilized soil. Detoxication by the fungi was not necessarily associated with marked proliferation in sterile soil,Trichoderma viride was an active colonizer of sterile soil but quite ineffective as a detoxicating agent.The phytotoxins could be readily leached out and their effects transmitted to sterile sand and irradiated soil. Results indicate that the toxicity is not due to changes in pH, soluble manganese or ammonia but is probably due to the formation of toxic organic materials.Primary root growth of subterranean clover is markedly stunted by toxins formed during heat-sterilization of soil and could provide an extremely sensitive bioassay for toxicity.Detoxication by micro-organisms may have been misinterpreted in the past as a direct stimulation of plant growth and caution is required in studies of the effects of micro-organisms upon plant growth.  相似文献   

7.
Incidence of Menkes disease   总被引:5,自引:0,他引:5  
Summary We have calculated the incidence of Menkes disease for Denmark, France, The Netherlands, the United Kingdom and West Germany, based on known Menkes patients born during the time period 1976–87. Considering live-born Menkes patients, the combined incidence for these five countries is 1 Menkes patient per 298000 live-born babies. If the number of affected aborted fetuses are taken into account, the incidence is 1 Menkes per 254000 live-born babies. This incidence, which is 2–4 times lower than earlier published incidence figures, places Menkes disease as an extremely rare disease. The mutation rate for Menkes disease is estimated to be 1.96 × 10–6, based on the number of isolated Menkes cases born during the time period 1976–87 and the total number of newborn males during this time.  相似文献   

8.
Analysis of data obtained in 25,787 Treponema pallidum immobilization tests in a ten-year period showed an increase in the incidence of biologic false positive (BFP) reactions for syphilis, and a decrease in the incidence of reactive TPI tests. The percentage of BFP tests increased from 54.2 per cent in 1953 to 70.7 per cent in 1962.Reaction to a standard serologic test for syphilis (STS) indicates only that the patient may have syphilis. A subsequent non-reactive TPI test remains the best procedure for ruling out a diagnosis of syphilis. Thus the clinician should be made more aware of the fact that a biologic false positive reaction strongly implies the existence of another disease, the cause of which should be investigated.  相似文献   

9.
Summary Extraction of a calcareous meadow soil with boiling formic acid containing 10 per cent acetylacetone yielded a fraction of soil organic matter representing about 40 per cent of the total. This fraction contained only 2.2 per cent N. Less than 18 per cent of this was mineralized during incubation for 8 weeks at 28°C. Further extraction of the soil with a formic acid and hydrofluoric acid mixture yielded a second fraction. This represented about 37 per cent of the total organic matter and contained 6.0 per cent N of which up to 41 per cent was mineralized during incubation. Preincubation and leaching had a stabilizing effect on subsequent mineralization of native N of a standard sandy loam soil.  相似文献   

10.
The viability of seeds of barley, broad beans, and peas hasbeen examined in hermetic storage over a range of temperaturesfrom 25? to 45? C and over a range of moisture contents fromabout 12 to 18 per cent. It was found that the survival curvesunder nearly all conditions can be described as negative cumulativenormal distributions. Under very severe storage conditions,however, when the mean viability period is of the order of aweek or less, the survival curves may become slightly skew.The spread of the distribution is linearly proportional to themean viability period. There is a negative linear relationshipbetween log mean viability period and both temperature and moisturecontent. Because of these relationships it is possible to predictthe percentage germination of these species after any givenperiod under a wide range of storage conditions. This patternof loss of viability in barley, broad beans, and peas is consistentwith that previously shown for wheat and rice. Oxygen has been shown to have a deleterious effect on the viabilityof barley, beans, and peas. Most of the deleterious effect isproduced by increasing the oxygen level from 0 per cent (nominal)to 21 per cent at atmospheric pressure; a further increase to100 per cent has comparatively little effect. The deleteriouseffect of oxygen is more pronounced at high moisture contents.Experiments at a low moisture content (12 per cent) have demonstratedthat the effect of oxygen is independent of the activity ofmicro-organisms. There is also some indication that the effectof oxygen is independent of the rate of seed respiration. The gas-exchange of pea seeds has been investigated in hermeticstorage at 25? C and 18.4 per cent moisture content. The seedsshowed a constant rate of gas-exchange and a constant R.Q. (0.63)over a period of time during which the concentration of oxygendecreased from 21 to I.4 per cent and the carbon dioxide concentrationrose from 0.03 to 12 per cent.  相似文献   

11.
The effect of the inoculum mycelium quality on carminomycin biosynthesis by Actinomadura carminata was studied. The time of the organism growth on the culture medium containing cornsteep liquor continued for 6 hours without losing by the inoculum of its seeding qualities during that period. The mycelium growth in the inoculum was more intensive under conditions of moderate aeration, i.e. 0.98-2.64 mg O2H1-min. Anincrease in the aeration rate up to 18.56 mg O2/1-min resulted in the growth suppression up to 40 per cent. No correlation between the aeration rate during the inoculum growth and the culture capacity for carminomycin biosynthesis and of the content of the complex in active components the fermentation medium were observed, when a 5-10 per cent of inoculum was used.  相似文献   

12.
Summary Changes in the pattern of distribution of the nitrogen of the soil and seedling grass plants have been investigated when the grass plants were grown in pots of sandy soil, from a pasture, at pH 5.7. Net mineralization of soil nitrogen was not observed during an experimental period of one month in the absence of added nitrogenous fertilizer (Table 2). Addition of labeled nitrogen (as ammonium sulphate) to the soil at the beginning of the experimental period resulted in a negative net mineralization during this period (Table 4b). When none of the fertilizer nitrogen remained in its original form in the soil it was found that approximately 12 per cent of the labeled nitrogen had been immobilized in soil organic compounds. Clipping of the grass at this date was followed by a decrease in the amount of labeled soil organic nitrogen, indicating that mineralization was not depressed by living plants. The application of unlabeled ammonium sulphate subsequent to the utilization of the labeled nitrogen did not decrease the amount of immobilized labeled nitrogen in the soil organic matter, as would be expected if the organic nitrogen compounds of the soil had been decomposed to ammonia. This was thought to be due to the fact that decomposition of organic nitrogen compounds in permanent grassland results in the production of peptides, amino acids etc. which are utilized by microorganisms without deamination taking place. In pots with ageing grass plants, labeled organic nitrogen compounds were found to be translocated from the grass shoots to the soil (Table 7). Net mineralization of soil organic nitrogen was positive in the contents of pots containing killed root systems (Table 3b). About 8 per cent of the labeled nitrogen added to the contents of such pots, in the form of ammonium sulphate, was found to be present in soil organic nitrogen compounds approximately 4 weeks after application, while a total of about twice this amount of soil organic nitrogen was mineralized during that period. From the results obtained in this investigation, it is concluded that the constant presence of living plants is responsible for the accumulation of nitrogen in organic compounds in permanent grassland. No evidence was obtained that the decomposition of such compounds in the soil is inhibited by living plants.  相似文献   

13.
Peptic ulcer is not an uncommon disease among the aged population. Thirty-five per cent of the patients admitted to the Los Angeles County General Hospital in a period of 12 months for treatment of peptic ulcer were more than 60 years of age.The severity of this disease in the elderly group was evidenced by the high incidence of lethal complications requiring operation—one case in every four.The mortality rate from operation for peptic ulcer complications is related to the factors of concurrent disease, the urgency of operation and the selection of a suitable operation.  相似文献   

14.
The total number of non-federal* physicians in California rose from 23,065 in mid-1959 to 26,271 in January, 1962, an 11.3 per cent increase. The proportion of physicians in private active practice remained almost constant during this period.A significant rise, both in number and proportionally, took place in the full-time specialty category, offset by losses in the general practice-part-time specialty group. While specialists increased by over 30 per cent, general practitioners, who made up 31.7 per cent of all non-federal physicians in 1959, were only 24.7 per cent of the total in early 1962.  相似文献   

15.
The objective of this work was to evaluate the effects of silicon acid and acibenzolar-S-methyl (ASM) on biology and behavior of the aphid (greenbug) in wheat plants. The experiment involved a 4 factorial (no silicon, silicon on leaf, silicon in the soil and silicon in the soil + on leaf), x 2 (with and without acibenzolar-S-methyl), in a completely randomized design. A preference test with chance of choice was set in blocks randomized, with 10 replications. Silicon acid was used at 1% and ASM at 0.5%. The treatments were evaluated by means of preference tests with chance of choice (adult aphids in leaf sections of wheat plants were counted), biological studies (length of pre-reproductive, reproductive and post-reproductive periods, mortality rate during the pre-productive period, number of nymphs, longevity and population growth rate were determined) and colonization of aphids (number of adult aphids and nymphs were determined). In the preference test, plants that received ASM were not chosen by the aphids. The application of the silicon or ASM reduced significantly the number of nymphs, the population growth rate, the post-reproductive period and the longevity of the greenbug. A significant reduction of the number of aphids was observed during aphids colonization when ASM or silicon were applied. The addition of silicon acid, mostly in the soil, or of ASM is promising as a control method in the integrated management of aphid in wheat.  相似文献   

16.
The mortality rate for cervical cancer in California declined during the period 1950-64. Indirect evidence shows that the incidence is also declining, but it is difficult to assess this decline because of the effect of the increasing use of cytologic examination on incidence rates for cervical cancer.Cervical cancer, in the 57 hospitals reporting to the California Tumor Registry, is being diagnosed at an earlier stage than in previous years. The proportion of cases diagnosed with the lesion still in the in situ stage rose from zero in 1942 to 56 per cent in 1963, and invasive cervical cancer, as a proportion of all invasive cancer in women, decreased from 15 per cent to 9 per cent. There is wide variation among hospitals in the proportion of cervical cancer cases that are in situ at time of diagnosis.  相似文献   

17.
Homosexuality is more prevalent in our society than many suspect.The incidence of infectious syphilis is increasing and the homosexual is playing an increasing role in its epidemiology.Fifteen per cent to 70 per cent of homosexuals practice analism.The diagnosis of venereal disease should always be kept in mind when dealing with anorectal problems.  相似文献   

18.
In the initial use of cytologic examination of smears to detect pulmonary and gastric cancer at the Los Angeles County Hospital during the period April 1949 to June 1950, 350 patients with suspicion of pulmonary disease and 128 with gastric problems were studied. In the pulmonary group, 80 per cent of 51 malignant lesions were diagnosed by the smear technique. Sixty per cent of 15 neoplasms in the stomach were diagnosed by the method. The results are analyzed in terms of sensitivity, accuracy, reliability and "yield" for the method. Cytological criteria of the presence of malignant disease are given and illustrated by photomicrographs. The method is one of potentially great value as an aid to diagnosis. Use of it in examination of selected categories of patients seems warranted.  相似文献   

19.
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   

20.
A review was made of the cases of 93 patients with burns covering more than 20 per cent of the body surface who were treated at the San Francisco City and County Hospital, University of California Service, between 1943 and 1956.The mortality rate increased from 40 per cent during 1943-1947 to 69 per cent during 1952-1956. A significant change in survival time was noted: During 1943-1947, 69 per cent of the deaths occurred within 48 hours of admission; during 1952-1956, only 19 per cent of the deaths occurred within the first 48 hours. In the period 1943-1947 the majority of deaths resulted from shock in the immediate post-burn period; in the later years of the study the major cause of death was infection.No patient more than 50 years of age who had burns of more than 25 per cent of the body surface survived. Only one patient with burns involving more than 45 per cent survived.No patient who had a blood culture positive for bacteria survived. The use of antibiotics had no effect on the incidence of infection. Elderly patients, children and alcoholics were less able to resist the effects of infection.The lowest mortality rate was in the age group of 15 through 35 years.  相似文献   

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