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1.
The mermithid,Hexamermis albicans (Siebold) was recovered from larvae ofLymantria (Porthetria) dispar (L.) collected from various localities in Burgenland, Austria in 1974 and 1975 and from Würzburg, Germany, in 1974. It was recovered also fromStilpnotia salicis (L.) in Austria in 1974. The mermithid was recovered from all field collected larval instars. The majority of the nematodes emerged fromL. dispar larvae collected as second and third larval instars although some nematodes were recorded from larvae collected as first instar larvae still on the egg mass. Peak emergence occurred in the laboratory during the period June 11–17 of both years, but emergence continued at a much lesser degree through the end of larval development. The nematode was found in both high and low host density populations. In 3 localities studied both years, there was a general increase in the percentage parasitism the second year. However, except for one locality in Austria in 1975 where individual samples produced up to 11% parasitism, the overall parasitism increased from 0.4% in 1974 to only 2.5% in 1975.  相似文献   

2.
S. Semchyshyn  V. J. Sorbara 《CMAJ》1976,115(2):115-116
An epidemic of rubella reached its peak in the Atlantic provinces in 1974, subsiding in early 1975. With the exception of Quebec the remainder of Canada showed a reverse trend, with a large increase in the numbers of cases reported in the first 41/2 months of 1975. The Halifax virus laboratory reported 106 serologically proven cases of rubella in 1974, 44 of them in pregnant women. In the aftermath of the epidemic many infants were born with the congenital rubella syndrome (CRS). A study carried out from Sept. 1, 1974 through Apr. 30, 1975 showed an 80% correlation between clinical diagnosis and the presence of rubella-specific IgM antibodies in 35 of these infants. Of the 23 infants in whom the diagnosis of CRS was made by laboratory or clinical findings or both, laboratory criteria were met in 20 (87.0%), clinical criteria in 19 (82.6%) and both laboratory and clinical criteria in 16 (69.6%).  相似文献   

3.
Using a unique set of birth registration data from the Demographic Surveillance System of the International Center for Diarrheal Disease Research, Bangladesh, for the period 1974-77, and socioeconomic information collected in the 1974 census, fertility was studied in relation to occupation, size of dwelling, number of cows and number of boats owned. The total fertility rate was found to vary between 6 and 6.5 except in the famine year of 1975. There was no consistent relationship between fertility and education of women. The age-specific fertility rates by religion show that Muslims had higher fertility at all ages in 1974 and 1977 and at older ages in 1975 and 1976. Overall, however, fertility of Hindus is consistently lower than that of Muslims, but the relative differences are under 10%. Fertility differentials by occupation showed that the household heads who were farm laborers had relatively lower fertility compared to other occupational groups, except for the year 1977 where the families of service holders were found to have relatively lower fertility. Women in households whose heads were businessmen or farmers (owning their land) had above average fertility. In 1974, households in the business occupational groups had, on average, 1 birth more than other households. Women in households with fishermen as heads had below average fertility in 1974 and 1975, but very high fertility in 1976 and 1977. Fertility levels differed according to the type of household in which the family resided. Nuclear families had below average fertility up to the age of 35 and above average fertility at the end of the reproductive age. In the 15-19 age group, augmented families had higher fertility each year examined. The association between dwelling place and fertility is positive each year, the relative differences in fertility between the groups being largest in 1974. Positive relations were found between economic status and fertility.  相似文献   

4.
An analysis of the inhibition of hemolytic plaques formed against IgM antibodies is presented. The starting point is the equations of DeLisi &; Bell (1974) which describe the kinetics of plaque growth, and DeLisi &; Goldstein (1975) which describe inhibition of IgG plaques. However, the physical chemical models which were used previously to describe IgG inhibition data are shown to be inadequate for describing the characteristics of IgM inhibition curves. Moreover, it is shown that the experimental results place severe restrictions on the possible choices of physical chemical models for IgM upon which to base the calculations. It is argued that in order to account even qualitatively for all the data, one must assume (1) a very restricted motion of IgMs about the Fab hinge region and (2) a very narrow secretion rate distribution of IgM by antibody secreting cells.  相似文献   

5.
Two collective bodies (319 persons in all) were under observation from October, 1974 to March, 1975 for the purpose of studying the problem on the participation of antibodies of the respiratory tract secretion in the protection from influenza virus, type A, infection. During the influenza epidemic outbreak there was revealed a reverse relationship between the antibody concentration in the nasal cavity secretion and the incidence of the disease, and also an interaction between the antibodies of the secretions and the serum in the influenza protection.  相似文献   

6.
Peripheral plasma progesterone and corticosteroid concentrations were studied in ewes grazing oestrogenic pastures during oestrus, pregnancy and parturition in 1974 and during pregnancy in 1975. Haemoglobin (Hb) type A ewes had significantly higher mean corticosteroid concentrations than HbB ewes in both years. In 1974 the concentration of progesterone did not differ significantly between Hb types whilst in 1975 the concentration was significantly (P less than 0.001) higher in HbA ewes. The mean corticosteroid concentrations were higher in selenium-supplemented ewes of both Hb types than in unsupplemented ewes in 1974 but lower in 1975. Selenium treatment did not significantly influence the progesterone concentration in ewes of both Hb types in 1974 but significantly (P less than 0.01) increased in 1975. It is concluded that the higher concentration of plasma corticosteroids or factors regulating the relationship between corticosteroids and progesterone could be responsible for the higher estimates of embryonic mortality reported in HbA ewes.  相似文献   

7.
The results of three serologically controlled double blind field trials in army units are presented. The evaluation of results according to morbidity, regardless of aetiology, showed a significant reduction in acute respiratory diseases (ARD) after administration of Impulsin. In the 1973 trial (901 volunteers), 22.7% of ARD cases were found in the Impulsin group contrary to 34.4% in the placebo group (P less than 0.0002). The relevant values in the 1974 trial (610 volunteers) were 19.7% and 40.7% (P less than 0.002) and in the 1975 trial (353 volunteers) 10.6% and 28.8% (P less than 0.004). The study of the immunological background in representative sets of volunteers allowed determination of the aetiology, the proportion of asymptomatic infections and possible deformation of results due to preexisting protective antibodies. Manifestation rate (MR) expressing the proportion of sick persons out of all sensitive subjects with serologically proved infection was found useful. This indicator is relatively independent of randomization and is more sensitive as compared to the incidence rate. In the 1973 trial, influenza A 2 England was prevalent, the MR of infection being 15.4% in the Impulsin group and 44.9% in the placebo group (P less than 0.0002). After elimination of persons with preinfection antibodies greater than or equal to 1:256 the corresponding values of MR were 17.6% and 46.6% (P less than 0.005), reflecting the "relatively clean effect" of Impulsin. In the 1974 trial, where influenza B Hong-Kong was prevalent, MR was 14.3% and 57.1%, respectively (P less than 0.001). Preinfection antibodies were negligible. The preliminary prophylactic index of the drug seemed to be 4.3 for combined adenoviral infections (trials 1973 and 1974 taken together). In the 1975 trial, the results of serological examination were unsatisfactory. Antibodies vs. influenza A Port Chalmers were found in 24.5% of ARD only. The differnce is aetiologically unclarified ARD was statistically significant. Although displaying a significant limitation of clinical infections, the administration of Impulsin did not seem to have any influence on the formation of antibodies.  相似文献   

8.
Synopsis Diet, growth, energy content and mercury concentrations of yearling yellow perch,Perca favescens, were determined from June 1974 through May 1975. Benthic invertebrates predominated in the diet throughout the summer with zooplankton important in June and fish in August and September. Ash, lipid, protein and energy content of the yearling yellow perch increased through the summer reaching maximal values in August, 1974. Fish collected May 15, 1975 has reduced ash, lipid., protein and energy content with an increased moisture content. Both protein and lipid were catabolized during overwintering. Seasonal variation in organic mercury concentration was not significant (p>0.05). Inorganic mercury decreased significantly (p0.05) in September, 1974 and May, 1975 samples, reflecting changes in diet and the shorter biological half-life of inorganic mercury. The pollutant bioaccumulation model of Norstrom et al. (1976) adequately described the observed accumulation of organic mercury in young perch from June through September 1974, but either underestimated uptake or overestimated clearance for the period October 1974–May 1975.  相似文献   

9.
Interactions between phytoplankton and zooplankton in a fertilized lake   总被引:3,自引:0,他引:3  
The limnology of an oligotrophic lake, Langvatn, situated in Trøndelag county in Central Norway, has been studied for five years (1974–1978). In two years, 1975 and 1976, the lake was fertilized with a general fertilizer to change feeding conditions for the zooplankton. Mean phytoplankton biomass in the epilimnion and primary production for the years (1974–1978) were 417, 618, 1370, 607 and 779 mg m−3 and 10.6, 22.2, 49.0, 26.8 and 17.7 g C m−2 yr−1, respectively. Cladocerans were the dominant herbivore group in 1974 and 1975 and Rotifera in the next three years. The main difference in the interaction between phytoplankton and zooplankton occurred when cladoceran dominance gave way to rotifer dominance. Heavy phytoplankton grazing by cladocerans in 1974 and 1975 stabilized the biomass and maintained it at a low level, which also resulted in a relatively low primary production. The rotifer-dominated community during the years 1976–1978 did not possess the ability to maintain a stable level of algal biomass. Primary production was also relatively high during these years.  相似文献   

10.
Phagosomes are critical compartments for innate immunity. However, their role in the protection against murine listeriosis has not been examined. We describe here that listericidal phago-receptosomes are induced by the function of IFN-γ or IL-6 as centralized compartments for innate and adaptive immunity because they are able to confer protection against murine listeriosis. These phago-receptosomes elicited LLO(91-99)/CD8(+)- and LLO(189-201)/CD4(+)-specific immune responses and recruited mature dendritic cells to the vaccination sites controlled by T cells. Moreover, they present exceptional features as efficient vaccine vectors. First, they compartmentalize a novel listericidal STAT-1-mediated signaling pathway that confines multiple innate immune components to the same environment. Second, they show features of MHC class II antigen-loading competent compartments for cathepsin-D-mediated LLO processing. Third, murine cathepsin-D deficiencies fail to develop protective immunity after vaccination with listericidal phago-receptosomes induced by IFN-γ or IL-6. Therefore, it appears that the connection of STAT-1 and cathepsin-D in a single compartment is relevant for protection against listeriosis.  相似文献   

11.
We used automated ribotyping on the RiboPrinter Microbial Characterization System to study the epidemiology of listeriosis in western Austria over the period 1988-1996. Thirty-six isolates containing three serotypes were included in this collection. Each of the 16 ribotype groupings (RiboGroups) produced in this study contained a single serotype. Isolates collected from within a single food factory environment all grouped into unique RiboGroups. One factory contained isolates showing two unique RiboGroups, both of which were also seen in patient isolates. This same set of Listeria isolates has previously been studied by automated laser fluorescence analysis of randomly amplified polymorphic DNA (RAPD-Alfa). The data produced by the RiboPrinter system correlated well with the epidemiological information, better than the results achieved with RAPD-Alfa. The RiboPrinter system provides a rapid, easy, and useful method for the typing of Listeria monocytogenes.  相似文献   

12.
We have used hydrogen-exchange labeling detected by 2D NMR to study antibody-protein interactions for two monoclonal antibodies raised against horse cytochrome c. The data show that these antibodies bind mainly to the large 37-59 omega-loop of the cytochrome c molecule. In addition, the results provide some suggestive evidence concerning units of local structural flexibility in cytochrome c.  相似文献   

13.
Summary Frequencies of three codominant alleles at the transferrin (Tf) locus and four of the six possible genotypes in a population of Nuttall's cottontails Sylvilagus nuttallii on an 87-ha study area in central Oregon were determined for parental stocks, trappable offspring, and over-winter survivors in 1974 and 1975. One rare allele disappeared during winter 1974–75 and did not reappear during the study. The Tf genotype frequency shifted in favor of Tf-BB between parents and offspring in 1974, remained stable over winter, shifted in favor of Tf-BC (to near the original frequency) between parents and offspring in 1975 and remained stable over winter. Allele and genotype frequencies were significantly different between 1974 and 1975 offspring; differences in frequencies between other samples were not significant because of the small number of cottontails that survived to spring each year. We were unable to discount the possibility of non-random breeding being responsible for observed differences, but, because survival of juveniles was related to moisture available for plant growth (and presumably to the moisture content in forage) during the cottontail breeding season and because frequencies of Tf genotypes of the four litters produced each year seemed related to available moisture, we postulated that precipitation was the selective force responsible for shifts in allele and genotype frequencies. Although we were unable to ascertain the probability that the polymorphism was balanced, the stochastic precipitation pattern seemed adequate to prevent fixation of an allele by selection if the selective mechanism was as postulated.  相似文献   

14.
1. Chymotrypsin cleaved troponin-T of skeletal muscle into two subfragments, i.e., troponin-T1 and -T2, each of which could be isolated by the use of DEAE-Sephadex. Troponin-T1 was a single subfragment with a molecular weight of 26,000 (chicken) or 22,000 (rabbit) daltons. Troponin-T2 consisted of two subfragments with molecular weights of about 13,000 daltons. Results obtained indicated that the smaller subfragment was formed by digestion of the larger subfragment of troponin-T2. 2. Antibodies against troponin-T1 and -T2 formed regular transverse striations along the whole length of thin filaments with 38 nm intervals, as was found reviously using antibodies against whole troponin complex as well as troponin components (Ohtsuki, I. et al., 1967; Ohtsuki, I. 1974 and 1975). 3. The first anti-troponin-T1 striation was situated 40 nm from the top of the filament. The first anti-troponin-T2 striation was 27 nm from the filament top and coincided with the first striations formed by antibodies against troponin-C or -I. 4. Troponin-T1 and the larger subfragment of troponin-T2 bound to tropomyosin which had been coupled to Sepharose, whereas the smaller subfragment of troponin-T2 did not.  相似文献   

15.
C. J. Vernon 《Ostrich》2013,84(2-3):89-94
Vernon, C. J. 1976. Eighteenth ringing report for southern Africa. Ostrich 47:89-94. A report on ringing activities in southern Africa from July 1974 to June 1975 is presented. A total of 47 777 birds of 475 species were ringed. This information is examined according to distribution of ringers, species ringed and recovery rates.  相似文献   

16.
Studies were conducted from April through August during 1974 and 1975 on 30 randomly selected trapping sites in Wall Doxey State Park, Holly Springs National Forest, and 1.6 km south of the park in Marshall County, Mississippi to provide information on the occurrence of ticks involved in the maintenance and transmission of spotted fever-group rickettsiae in nature. Of 365 animals (14 species) collected, 186 (51%) were parasitized by 4,169 ticks. Species of ticks collected included: Dermacentor variabilis; Amblyomma americanum; Rhipicephalus sanguineus; Haemaphysalis leporispalustris; and Ixodes texanus. Of 2,105 ticks examined, 116 (5.5%) were positive for rickettsia-like organisms.  相似文献   

17.
The amino acid sequence of the V (variable) region of the heavy (H) chain of rabbit antibody BS-1, raised against type III pneumococcal vaccine, is reported. Together with the sequence data of the V region of the light (L) chain previously determined [Jaton (1974a) Biochem. J. 141, 1-13], the present work completes the analysis of the V domain of the homogeneous antibody BS-1. The V domains (VL + VH regions) of this antibody are compared with those of two other anti-(type III) pneumococcal antibodies BS-5 and K-25 [Jaton (1975) Biochem. J. 147, 235-247]. Except for the second hypervariable section of the L chains, these antibodies have very different sequences in the hypervariable segments of the V domains. Within the third hypervariable region of the H chain, each antibody has a different length: BS-1 is three amino acids shorter than K-25 and two amino acids shorter than BS-5. When the sequences in that section are aligned for maximal homology, only two residues, glycine-97 and leucine-101, are common to the three antibodies. On the basis of the amino acid sequences of these three anti-pneumococcal antibodies, the results do not support the concept of a simple correlation between primary structure in the hypervariable sections (known to determine the shape of the combining site) and antigen-binding specificity.  相似文献   

18.
A T Shabalina  I T Iotova 《Genetika》1977,13(5):821-825
The experiments were carried out on White Leghorn, White Rock and Cornish chickens during the 1974--1975 season. The aim of the investigation was to study polymorphism of blood esterases in chickens in relation to their resistance to Salmonella pullorum and S. gallinarum. The data obtained indicate the following: 1) an additional, inheritant alyesterase fraction (A1) Appears in blood serum of resistant chickens after their contamination with Salmonella; 2) most chickens, which are resistant to Salmonella, have heterozygous genotype for blood serum cholinesterase.  相似文献   

19.
A free-ranging troop of Japanese monkeys was observed for seven years from April 1971 to March 1978 in the Hakone area, Kanagawa Prefecture, Japan. This troop was fed artificially between 1956 and 1977. The artificial food supply was reduced by about half after 1974. The troop-size fluctuated around 100 between 1971 and 1974, but fell drastically from 91 in 1975 to 58 in 1978. Population parameters were compared between the two periods of 1971–1974 and 1975–1977. Clear differences between the two periods were found in primiparous age, ratio of non-natal resident males to all resident males, ratio of newcomers to non-natal resident males, age-specific disappearance rate, and proportion of deserters observed in the study area. A correlation existed between the number of males and females of 5 or more years of age in the troop. The numbers in the three age-sex groups (natal males, non-natal males, and females of 5 or more years of age in the troop) were closely connected with one another. The scarcity of food supply may have caused not only males but also females to disperse. The drastic decrease in troop-size after 1974 could be based on the disappearance of adult females. The cause of the dispersal of young males and adult females could have been mutual competition among the troop members for food, and that in adult males could have been competition for females.  相似文献   

20.
目的描述我国1964-2009年文献报告的非围产期李斯特菌病的临床与流行病学特征,为李斯特菌病的防治提供科学依据。方法计算机检索与手工检索结合收集我国1964.1-2009.12非围产期李斯特菌病的文献报告资料,从中提取各非围产期李斯特菌病例的临床与流行病学信息并进行统计分析。结果共纳入66例非围产期李斯特菌病例,其中以男性、年龄35岁者居多。患者的临床表现以CNS感染(42%)、败血症(41%)为主。免疫缺陷患者多表现为CNS感染,非免疫缺陷患者多表现为败血症。报告病例总死亡率为19%(11/57),其中免疫缺陷患者的死亡率高达28%(5/18)。结论我国非围产期李斯特菌病的临床特点与国外报告相符,报告死亡率与国外类似。  相似文献   

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