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1.
In this study, cloacal myiasis caused by dipterans of Lucilia genus was found in a rooster (Gallus gallus domesticus) and two Harris's hawks (Parabuteo unicinctus) from Peru. Larval dipteran were collected and preserved in ethanol. Morphological analysis indicated two species: Lucilia sericata in the rooster and in one Harris's hawk, and Lucilia cuprina in the other Harris's hawk. Molecular analysis confirmed the diagnosis by amplification of the nucleotide sequences of the cytochrome c oxidase subunit 1 gene and internal transcribed spacer 2 region. The sequences were compared with sequence references from a public sequence database, which showed a 100% matched identity. This study demonstrated for first time cloacal myiasis by L. sericata in a domestic bird from Peru and in Harris's hawk. Also, for the first time, L. cuprina was found in a bird of prey.  相似文献   

2.
Transverse lines in long bones of prehistoric California Indians   总被引:1,自引:0,他引:1  
Radiopaque transverse lines (lines of arrested growth, Harris's lines) were counted on X-rays of the distal end of 102 adult femurs from prehistoric California Indian populations representing three archaeological Horizons. The sample from Early Horizon has the highest frequency of lines, the Middle Horizon the next, and the sample from Late Horizon has the lowest frequency of lines. These differences are statistically significant. Archaeological evidence indicates that the Indians improved and broadened their subsistence economy from Early to Late Horizon. It is concluded that the differences in the frequency of lines among the three California Indian populations probably are associated with differences in morbidity and/or nutritional status of the people. If this hypothesis is correct, then frequency distribution of transverse lines represents a valuable tool for the paleopathologist and the archaeologist.  相似文献   

3.
Transverse lines were examined in 633 long bones from 73 individuals exhumed from two burial sites in the Republic of Ireland: Waterford City and Tintern Abbey. The burials cover four distinct periods between the 11th and 17th centuries. Lines were most numerous in the tibia, especially in the distal segment, and were not seen in the humerus nor the proximal part of the femur. The number of lines varied between the proximal and distal segments of each long bone, and though apparently equal in number across the midline, there were significant differences in the incidence of lines between corresponding pairs of bones. Thus, it is unwise to rely on the results of a single bone or one type of long bone alone either to indicate the health status of an individual, or as the basis for assessing the health status of a small population. Such results should be used only in association with other indicators. © 1996 Wiley-Liss, Inc.  相似文献   

4.
Usually, stepwise selection of plant suspension cultures with gradually increasing concentrations of the herbicide glyphosate results in the amplification of the target enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS; EC 2.5.1.19) gene that leads to resistance by increasing EPSPS mRNA and enzyme activity. We show that glyphosate selection with newly initiated suspension cultures can produce resistant lines with resistance mechanisms other than gene amplification and that usually as the cultures age gene amplification becomes the predominant mechanism. Gene amplification did not occur in 3 lines selected from 5-month-old Datura innoxia Mill. cultures but did occur in all 10 lines selected after 52 months. Selection with Nicotiana tabacum L. (tobacco) less than 5 months old produced 2 lines out of 24 with no EPSPS amplification while all 17 lines selected from older cultures contained amplified genes. Lines selected from the oldest culture (35 years) also exhibited amplification of several different genes, indicating the expression of different EPSPS genes or an enhanced gene amplification incidence. None of the 15 lines selected from 2 different 5-month-old Daucus carota L. (carrot) lines exhibited amplification while amplification led to the resistance of all 7 lines selected from one of the original carrot lines (DHL) after 3 years. However, the other line (Car4) was exceptional and produced only non-amplified lines (9 of 9) after 8 years in culture. These results show that plant tissue cultures change with time in culture and that several different new mechanisms can result in glyphosate resistance.Abbreviations AHAS acetohydroxyacid synthase - EPSPS 5-enolpyruvylshikimate-3-phosphate synthase  相似文献   

5.
The formation and persistence of radiopaque transverse lines have been assessed in the living in clinical studies of growth, nutrition, and disease. Lines have also been used by many researchers in the analysis of patterns of childhood stress in prehistoric skeletal materials, although most of this research has been undertaken on adult bones. However, how reliable and useful are transverse lines for interpretations of stress? The precise etiologies for their appearance are varied and controversial, and lines are also known to resorb during both childhood and the adult years. Sex differences in both their formation and persistence have also been reported. To assess better the viability of lines as indicators of stress, the present research analyzes rates of formation, distribution frequencies, and the persistence of transverse lines in individuals aged birth to 50 + years from a single archaeological population. The results suggest that while transverse lines may be analytically useful as subsidiary criteria for more fully understanding the biological well-being of prehistoric populations, caution should be exercised in the interpretations made concerning childhood stress, particularly when using adult bones.  相似文献   

6.
The life history of Risso's dolphins (Grampus griseus) remains poorly known and data from strandings can help provide important information. Data from 126 Risso's dolphins stranded or bycaught along the southeastern coastline of South Africa between 1958 and 2017 were analyzed in relation to their sex, age structure, and diet. Mean estimated length at birth was 146.9 cm, while maximum length was 325 cm for males and 313 cm for females; small sample sizes precluded detailed examination of sexual dimorphism. Age estimates for 33 individuals (14 males, 17 females, 2 unknown sex) indicated a maximum age of 13 years (males) and 17 years (females), respectively; the oldest animal was 19 years (unknown sex). Mean length and age at attainment of sexual maturity were estimated at 280 cm and 7.1 years in males and at 282 cm and 7.7 years in females. Stomach contents from 27 individuals showed that diets of immature and mature males and females overlapped and consisted predominantly of cephalopods. Reported strandings decreased between 2000 and 2017, possibly due to a lack of reporting associated with a ban on driving on beaches or related to the collapse of the local “chokka” squid (Loligo reynaudii) fishery in 2014–2015.  相似文献   

7.
Of eight patients with Paget''s disease one had diarrhoea, steatorrhoea, impaired xylose absorption, and macrocytic anaemia due to folic acid deficiency, while another had diarrhoea and very low xylose absorption. In both patients jejunal biopsy was normal, and they responded to folic acid therapy with considerable increase in xylose absorption. Low xylose excretion was seen in three more patients, one of whom also had steatorrhoea. Thus malabsorption may be a systemic complication of Paget''s disease of bone, possibly due either to secondary folate deficiency or to relative ischaemia of the bowel.  相似文献   

8.
《CMAJ》1977,117(5):461-476
Autopsy of a 3200-year-old Egyptian mummy by an international multidisciplinary team yielded much information about diseases of the ancient past. Major contributions were made by the disciplines of anatomy, dentistry, genetics, hematology, histology, microbiology, nuclear medicine, occupational medicine, orthopedic surgery, otolaryngology, pathology, pediatrics, plastic surgery, radiology and virology. Scientists from Toronto, Detroit, Philadelphia and Cardiff participated in the investigation. The following were the main findings of medical interest: skeleton, infection or malnutrition as suggested by Harris''s lines in distal femoral metaphyses; muscle (intercostal), cyst of Trichinella spiralis; lungs, deposits of anthracotic pigment and granite particles; spleen, enlargement with evidence of possible rupture; liver, early cirrhosis and calcified ova of Schistosoma sp.; kidney, calcified ova of Schistosoma sp.; and large and small intestines, calcified ova of Schistosoma and Taenia spp. This autopsy demonstrated the value of well coordinated efforts by specialists in various medical disciplines. Such efforts are essential when such a rare scientific endeavour is to yield a maximum of useful and reliable information.  相似文献   

9.
The Kommandorskiye Islands population of Steller''s sea cow (Hydrodamalis gigas) was extirpated ca 1768 CE. Until now, Steller''s sea cow was thought to be restricted in historic times to Bering and Copper Islands, Russia, with other records in the last millennium from the western Aleutian Islands. However, Steller''s sea cow bone has been obtained by the authors from St Lawrence Island, Alaska, which is significantly further north. Bone identity was verified using analysis of mitochondrial DNA. The nitrogen-15 (δ15N)/carbon-13 (δ13C) values for bone samples from St Lawrence Island were significantly (p ≤ 0.05) different from Bering Island samples, indicating a second population. Bone samples were dated to between 1030 and 1150 BP (approx. 800–920 CE). The samples date from close to the beginning of the mediaeval warm period, which could indicate that the population at St Lawrence Island was driven to extinction by climate change. A warming of the climate in the area may have changed the availability of kelp; alternatively or in addition, the animals may have been driven to extinction by the expansion of the Inuit from the Bering Strait region, possibly due to opening waterways, maybe following bowhead whales (Balaena mysticetus), or searching for iron and copper. This study provides evidence for a previously unknown population of sea cows in the North Pacific within the past 1000 years and a second Steller''s sea cow extirpation event in recent history.  相似文献   

10.
Lines of Chinese hamster ovary cells resistant to the lectins concanavalin A (Con A) and phytohemagglutinin-P (PHA-P) have been isolated and characterized. Lines were isolated by a stepwise, a single-step, or a cycling single-step procedure, from both mutagen-treated and untreated cultures. The resistant lines showed a higher efficiency of colony formation in the presence of the appropriate lectin than did the wild-type parental line. The cell lines resistant to Con A did not exhibit any detectable cross resistance to PHA-P, nor did the PHA-resistant cells exhibit cross resistance to Con A. The toxicity of Con A from the wild-type and Con A-resistant lines was reduced in the presence of methyl α-D-glucopyranoside; this effect was not seen with the PHA-resistant line. Using 125I-labeled Con A, it was found that Con A was bound preferentially to the surface of intact cells, and that the amount of labeled Con A bound to intact cells was similar for the wild-type and lectin-resistant lines. The Con A-resistant lines were found to be more susceptible to the toxic effects of a number of different compounds, including cyclic AMP and its dibutyryl derivative, sodium butyrate, high concentrations of glucose, phenethyl alcohol, phenol, ouabain, and testosterone. It appears that, in these lines, acquisition of resistance to Con A gave rise to pleiotropic effects which were detected by changes in the sensitivity of the cells to a variety of agents.  相似文献   

11.
Extensive osteolytic and osteoblastic lesions were observed on the skeletal remains of an adult male excavated from an Early Bronze Age cemetery dated to 4556+32 years BP, located in the Cis-Baikal region of Siberia (Russian Federation). Lytic lesions ranged in size from several mm to over 60 mm in diameter and had irregular, moth-eaten borders. Many of these lesions destroyed trabecular bone, though a hollowed shell of cortical bone often remained observable. Radiographic analysis revealed numerous lytic lesions within trabecular bone that had not yet affected the cortex. Blastic lesions were identified as spiculated lines, bands, or nodules of mostly immature (woven) bone formed at irregular intervals. Anatomical elements with the greatest involvement included those of the axial skeleton (skull, vertebrae, sacrum, ribs, and sternum) as well as proximal appendicular elements (ossa coxae, proximal femora, clavicles, scapulae, and proximal humeri). Osteocoalescence of destructive foci was observed on the ilium and frontal bone, with the largest lesion found on the right ilium. Differential diagnoses include metastatic carcinoma, mycotic infections, tuberculosis, Langerhan''s cell histiocytosis, and multiple myeloma. Based on lesion appearance and distribution, age and sex of the individual, as well as pathogen endemism, the most likely diagnostic option for this set of lesions is metastatic carcinoma. The age and sex of this individual and appearance of the lesions may reflect carcinoma of the lung or, possibly, prostate. This represents one of the earliest cases of metastatic carcinoma worldwide and the oldest case documented thus far from Northeast Asia.  相似文献   

12.
Human peripheral blood lymphocytes (PBLs) can have a range of O6-methylguanine-DNA methyltransferase (MGMT) activities. PBLs from some individuals may have almost no MGMT activity. Such individuals have most often been subject to malignancy or to immunodeficiency disease. Long-term lymphoblastoid lines (LCLs) prepared from PBLs of normal subjects by Epstein-Barr virus (EBV) transformation have MGMT activities which are in general somewhat higher than the PBLs from which they derive. Such cultures are therefore generally MGMT-positive. Only in rare cases, and generally from patients with low MGMT activity, are freshly obtained lines with very low activity obtained. There is however a 4-fold range of MGMT activity over which multiple lines derived from the same PBL sample can be found. Long-term cultivation can lead to LCLs with low activity as well as to lines of high activity. On rare occasions an MGMT-positive line may, within a few divisions, give a negative line. Some (but not all) MGMT-negative (or very low) lines have been known to gain (some) activity. Chinese hamster ovary (CHO) cell lines are in general very low in MGMT activity. Lines of higher activity can be selected by treatment with mutagenic crosslinking alkylating agents. Chinese hamster lines with high MGMT activity can be obtained by transfection with human DNA from MGMT-positive cells. Lines with significant activity can also be obtained by transfection of CHO cells with human DNA from MGMT-negative (or very low) cells. Resistance to MNNG treatment can be acquired without the acquisition of significant MGMT activity. Crosses of lines of high and low MGMT activity give equivocal results. Hybrids of low × low activity have no activity. Crosses of positive × positive strains give varied results. It has not been possible to identify MGMT-positive hybrids as including one particular chromosome by this type of experiment. There is no evidence for a general adaptive effect on MGMT synthesis greater than the variation within the cell cycle.  相似文献   

13.
It has been found that Drosophila melanogaster lines from the “Chateau Tahbilk” winery cellar had higher larval ethanol resistance than lines originating from outside the cellar. Because the adaptive significance of this trait is unclear, we have reexamined genetic microdifferentiation at Tahbilk with other resources and different tests for ethanol adaptation. Cellar stocks tended to be more resistant to starvation after exposure to wine seepage than stocks originating from orchard traps outside the cellar. Lines from a grape residue pile were also more resistant to starvation after seepage exposure than orchard stocks even though these collection sites were a few meters apart. Cellar and orchard stocks did not differ in ethanol resistance as measured by larval viability tests on low sucrose medium. However, stocks from the grape residue pile showed an increase in adult longevity over ethanol vapor compared to those from the cellar or orchard stocks. These differences were not due to maternal effects. In laboratory tests of behavioral responses, cellar stocks were relatively more attracted to seepage than orchard stocks in one year but not in the other two years. The findings suggest some adaptive differentiation related to resource heterogeneity at Tahbilk.  相似文献   

14.
Longevity and age at sexual maturity were estimated in two anurans from the arid Isalo Massif (southern-central Madagascar), the blue-legged frog (Mantella expectata) and the rainbow frog (Scaphiophryne gottlebei). Phalanges from 69 individuals of M. expectata and 38 individuals of S. gottlebei were analyzed, using the skeletochronological method, in samples collected during two periods: January-February and November-December 2004. The male gonads of both species were also analyzed in order to better correlate reproductive activity with phenology. The phalangeal diaphysis in adults of both species was composed of two concentric bone layers: an innermost endosteal bone, which was less developed or sometimes lacking in S. gottlebei, and an outermost and broader layer of periosteal bone. Lines of arrested growth (LAGs) were observed in both species, although their recognition was more problematic and their distinctiveness much less evident in S. gottlebei. The results presented here indicate that M. expectata and S. gottlebei have a short life span and attain sexual maturity within the first active season after metamorphosis. Maximum longevity was 3 years in M. expectata and 2 years in S. gottlebei. In S. gottlebei the adult body size is likely attained during the same season in which metamorphosis occurs, but then breeding occurs only after the first latency period. Thus, mature individuals have only one LAG, corresponding to 1 year. The low number of individuals with two LAGs suggests that most animals die before the second latency period.  相似文献   

15.
Fibroblast cultures derived from skin biopsies of patients with Fanconi anemia had doubling times (mean of five lines: 30.3 ± 0.2 hours) significantly longer than randomly selected normal controls (mean of nine lines: 22.9 ± 0.4 hours). Control cultures grew more slowly in the enriched media RPMI 1640 and McCoy's 5A than in MEM, while a culture from a patient with Fanconi anemia grew more slowly only in McCoy's 5A. Differences in growth characteristics between Fanconi anemia and normal cell cultures may be useful in analyzing the metabolic error determined by the Fanconi anemia gene.  相似文献   

16.
The genetics of hemolymph alpha-mannosidase was investigated in the silkworm, Bombyx mori. By selecting individuals showing either high or low enzyme activities, homozygotes were separated, with activities varying about five-fold. No differences in the activities of beta-galactosidase and beta-N-acetylglucosaminidase were observed. Thus, it seems that high- and low-enzyme silkworms (High and Low Lines) share the same genetic background except for the gene concerning the activity of alpha-mannosidase. The synthesis of the enzyme is controlled by an autosomal allele. Furthermore, expression of the gene varies from tissue to tissue, and there is no correlation between enzyme activity and growth rate. The difference in activity between High and Low lines is due to the amount of active enzyme, not to an endogeneous activator or inhibitor. There was no isozymic difference in alpha-mannosidase.  相似文献   

17.
Eye contact has a fundamental role in human social interaction. The special appearance of the human eye (i.e., white sclera contrasted with a coloured iris) implies the importance of detecting another person''s face through eye contact. Empirical studies have demonstrated that faces making eye contact are detected quickly and processed preferentially (i.e., the eye contact effect). Such sensitivity to eye contact seems to be innate and universal among humans; however, several studies suggest that cultural norms affect eye contact behaviours. For example, Japanese individuals exhibit less eye contact than do individuals from Western European or North American cultures. However, how culture modulates eye contact behaviour is unclear. The present study investigated cultural differences in autonomic correlates of attentional orienting (i.e., heart rate) and looking time. Additionally, we examined evaluative ratings of eye contact with another real person, displaying an emotionally neutral expression, between participants from Western European (Finnish) and East Asian (Japanese) cultures. Our results showed that eye contact elicited stronger heart rate deceleration responses (i.e., attentional orienting), shorter looking times, and higher ratings of subjective feelings of arousal as compared to averted gaze in both cultures. Instead, cultural differences in the eye contact effect were observed in various evaluative responses regarding the stimulus faces (e.g., facial emotion, approachability etc.). The rating results suggest that individuals from an East Asian culture perceive another''s face as being angrier, unapproachable, and unpleasant when making eye contact as compared to individuals from a Western European culture. The rating results also revealed that gaze direction (direct vs. averted) could influence perceptions about another person''s facial affect and disposition. These results suggest that cultural differences in eye contact behaviour emerge from differential display rules and cultural norms, as opposed to culture affecting eye contact behaviour directly at the physiological level.  相似文献   

18.
The observed respect and attention to elders'' speech in traditional cultures appears to have a ‘universal’ component which questions its possible biological bases. Animals present differential attention to the vocalizations of other individuals according to their characteristics but little is known about the potential propensity to pay more attention to vocalizations of elders. On the basis of several hundreds of vocal exchanges recorded, here we show that aged female Campbell''s monkeys (Cercopithecus campbelli), despite being significantly less ‘loquacious’ than their younger adult counterparts, elicit many more responses when calling. These findings show that attention to elders'' vocal production appears in non-human primates, leading to new lines of questioning on human culture and language evolution.  相似文献   

19.
The Indo‐Australian region was formed by the collision of the Australian and Asian plates, and its fauna largely reflects this dual origin. Lydekker's and Wallace's Lines represent biogeographic transition boundaries between biotas although their permeability through geological times was rarely assessed. Here, we explore the evolutionary history of flightless weevils of the tribe Celeuthetini in this geologically highly complex region. We generated a DNA sequence data set of 2236 bp comprising two nuclear and two mitochondrial markers for 62 species of the Indo‐Australian tribe Celeuthetini. We used Bayesian Inference and Maximum Likelihood to reconstruct the first molecular phylogeny of the group. Based on this phylogenetic tree, we employed the program BioGeoBEARS to infer the biogeographical history of Celeuthetini in the region. The group's radiation begun east of Wallace's Line, probably during the mid‐Eocene. We unveil multiple transgressions of Lydekker's and Wallace's Lines mostly during the Miocene with a significant role of founder‐event speciation. The phylogeny of Celeuthetini is geographically highly structured with the first lineages occurring in New Guinea and the Moluccas, and a deep divergence between two clades largely confined to Sulawesi and their respective sister clades of the Lesser Sunda Islands. Wallace's Line was crossed once from Sulawesi and three times from the Lesser Sunda Islands to Java whilst Lydekker's Line was crossed once from New Guinea to the Moluccas. Although this beetle group shows extensive local diversification with little dispersal, the biogeographical demarcations of the Australasian region appear to have been rather porous barriers to dispersal.  相似文献   

20.
Lines of the fly Drosophila melanogaster were selected for increased knockdown resistance to heat (39 degrees C) in a long tube. One set of lines was selected following prior heat hardening (1 h at 37 degrees C) and another without hardening. Each set consisted of three replicate selection lines and three unselected controls. Lines were tested for correlated responses to selection, in order to define the nature of knockdown resistance. Selection had a large effect on knockdown resistance, but selected lines did not differ from controls for knockdown time in small vials, survival, or recovery time following exposure to heat. Selection with and without hardening influenced the hardening response in the long tube, but not in small vial assays of resistance. The hardened selection lines had decreased resistance to ethanol and a reduced dry weight, whereas the non-hardened lines did not show these changes. The same correlated responses were also evident in two generation experiments on unselected flies. Both sets of lines showed a reduction in activity when tested at 37 degrees C, but not at 25 degrees C. These results indicate that different measures of heat resistance are surprisingly unrelated, and suggest that subtle features of the selective environment influence responses and correlated responses to selection. Copyright 1997 Elsevier Science Ltd. All rights reserved  相似文献   

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