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1.
Reports of limb deformities in amphibians have garnered wide notice from scientists and the public alike. Recent laboratory and field research has supported the hypothesis that infection by the helminth parasite, Ribeiroia ondatrae, is associated with deformities, particularly in the western United States. In this study, observational and experimental evidence from eastern United States (Vermont) provides evidence that Ribeiroia is absent from a large sample of sites including those with a history of relatively high frequencies of deformity, that the composition of deformities is distinct from that associated with experimental infection by Ribeiroia, and that the composition of limb deformities seen in natural populations in Vermont is typical of that reported in the literature. We suggest that while Ribeiroia has been shown to be responsible for deformities in some species and locations, other factors may be responsible where the composition of deformities is inconsistent with patterns resulting from known Ribeiroia infection.  相似文献   

2.
Synopsis We described skeletal deformities in Willamette River fishes from larval and juvenile specimens collected in 2002 and 2003. Deformities were found in most taxa examined but were more frequent in native broadcast spawners, especially minnows and suckers, than in native or exotic nest builders. Caudal deformities were uniformly distributed throughout the river, but precaudal deformities were more localized near the towns of Newberg and Salem (Wheatland Ferry). In northern pikeminnow, Ptychocheilus oregonensis, deformities were dependent on relative hatch date, with early season fish having about three times the deformity load as late season fish. In a subsample of northern pikeminnow and chiselmouth, Acrocheilus alutaceus, number of deformities was directly related to number of trematode metacercariae and precaudal deformities were twice as likely as caudal deformities to be associated with metacercariae. Based on a logistic regression, the probability of a precaudal deformity was dependent on number of metacercariae and geographic area with the area effect disappearing as the number of cysts increased. A separate analysis showed that some types of deformities were unlikely to be associated with metacercariae. However, even in cases where metacercariae were unlikely to be associated with deformities, metacercariae were usually present elsewhere in the fish and an indirect effect could not be dismissed. The taxonomic, spatial and temporal patterns of skeletal deformities in Willamette River fishes may be due to differences in intermediate host (snail or fish) resistance or susceptibility to parasites, to differences in life history ecology, or to anthropogenic effects that are manifest in increased precaudal deformities near Newberg and Wheatland Ferry or decreased rates elsewhere.  相似文献   

3.
4.
Treatment options for the craniosynostoses vary from conservative observation until completion of growth to radical remodeling in infancy. To further define the timing and type of treatment necessary in these complex disorders, we have retrospectively analyzed all patients operated on for this deformity during the past 12 years. One-hundred and sixty-four patients with craniosynostosis were analyzed and subgrouped into asymmetrical (predominantly unilateral) and symmetrical (bilateral) deformities, in addition to segregation by age and type of procedure performed. This was done recognizing that no deformity, like no normal human face, is truly symmetrical. Results of treatment were categorized on the basis of the need for additional surgery and varied from no refinements necessary (category I) to major reduplication of the initial procedure (category IV). Analysis of the data led us to conclude that excellent results can be expected in the asymmetrical deformities group treated in infancy by a unilateral approach. Similarly, for the mild symmetrical deformities, treatment at this time by bilateral orbital advancement gives satisfactory results in the majority of patients. By contrast, the more severe symmetrical groups treated in childhood have a high incidence of requiring secondary major reconstructions, and consideration should be given to delaying craniofacial surgery until age 7 or older, although earlier cranial surgery may be advisable.  相似文献   

5.
Honey bees (Apis mellifera) productively infected with Deformed wing virus (DWV) through Varroa destructor (V. destructor) during pupal stages develop into adults showing wing and other morphological deformities. Here, we report for the first time the occurrence of bumble bees (Bombus terrestris, Bombus pascuorum) exhibiting wing deformities resembling those seen in clinically DWV-infected honey bees. Using specific RT-PCR protocols for the detection of DWV followed by sequencing of the PCR products we could demonstrate that the bumble bees were indeed infected with DWV. Since such deformed bumble bees are not viable DWV infection may pose a serious threat to bumble bee populations.  相似文献   

6.
The experiment was aimed at demonstrating the relationship between deformities of the front part of the prosoma accompanied by changes in the brain structure in bicephalous Tegenaria atrica and exposure of their embryos to temperature fluctuations. By exposing spider embryos to alternating temperatures of 14 and 32 °C for the first 10 days of embryonic development, we obtained eight two-headed individuals, subsequently divided into three groups according to morphological differences. We described in detail morphological abnormalities of the prosoma identified in members of each group. Histological examination confirmed a close relationship between morphological deformities and the brain structure of teratogenically changed spiders. The fusion of appendages (pedipalps and chalicerae) was accompanied by the fusion of corresponding ganglia. The absence of appendages (pedipalps) was accompanied by the absence of corresponding ganglia. This correlation may have resulted from previously impaired neuromere development which led to changes in the morphological structure of the prosoma. Since no deformities were identified in control animals, it can be concluded that bicephaly was caused by exposing embryos to alternating temperatures.  相似文献   

7.
We used trematode cyst infestation to induce limb deformities in two species of frogs of the genus Rana and compared them to deformities induced by surgical limb bud rotations. The specific deformities produced by both treatments closely resemble those of wild-caught deformed amphibians and are consistent with a known developmental response to disruption of the spatial organization of cells in developing limb buds. Histological analysis showed that trematode cysts cause massive disruption and abnormal cellular growth involving the limb buds of infected individuals. Our results indicate that trematode cyst infestation causes deformities in frogs by perturbation of the positional relationships of cells in developing limb buds. The crippling effects of cyst-infection on frogs may reflect complex co-evolutionary interactions among trematodes, frogs, and other hosts in the trematode's life cycle.  相似文献   

8.
Strauch B  Greenspun D  Levine J  Baum T 《Plastic and reconstructive surgery》2004,113(3):1044-8; discussion 1049
Various techniques for the management of upper extremity contour deformities have been suggested since aesthetic brachioplasty was first described. Such deformities are commonplace with aging, after normal weight loss, and especially after massive weight loss such as is seen following bariatric surgery. Despite the multiplicity of procedures described for the correction of these deformities, there are still problems associated with current brachioplasty techniques, including incorrectly placed incisions, widened hypertrophic scars, and postoperative contour deformities. In addition, postoperative skin laxity and ptosis in the axillary region are frequently encountered in the more extreme deformities. The authors present their technique for upper extremity brachioplasty. This technique is suitable for patients with severe brachial ptosis and skin laxity, with relatively little lipomatous tissue, which may extend from the olecranon to the chest wall. The described surgical approach provides excellent overall extremity contour with favorable scars while simultaneously addressing axillary contour deformities.  相似文献   

9.
Six cases are described in which defects of the femora are associated with deformities of the upper limbs. From the available literature all cases (55) were selected in which femoral defects were associated with upper limb deformities. It became apparent that most if not all of these cases belong to a well defined syndrome. Arm deformities associated with femoral defect do not usually include the most common types, but specific rare types, namely amelia, peromelia ending at the level of the elbow, brachioradial synostosis and ulnar defects. In the syndrome in question sometimes either arm shows a different type of these deformities, which is further evidence that all cases may be considered to represent one category. In the majority of cases there is also a defect of the fibula and the fibular rays. The etiology is unknown. Familial occurrence has not been observed. Parental age does not appear to be a factor. In no case was there a thalidomide history. A history of radiation exposure during pregnancy was present in two previously published cases. Other limb deformities associated with radiation exposure in utero are quoted from the literature. Some of them are similar, but not exactly identical to the syndrome in question.Thalidomide deformities, in which the radial and tibial rays are preferentially affected, are clearly distinct. Similar defects of the femorae and fibulae but not of the arms are occasionally seen in children born to diabetic mothers.  相似文献   

10.
Craniofacial contour deformities are difficult to reconstruct. This article summarizes the authors' use of deep inferior epigastric perforator dermal-fat or adiposal flaps in eight patients with such deformities. Of these patients, three had traumatic craniofacial or facial deformities, one had congenital craniofacial deformity, two had hemifacial atrophy (one because of radiation), one had hemifacial microsomia, and one had localized frontonasal lipodystrophy. Stable restoration of the facial contour was achieved in all eight patients. The advantages of this flap are numerous. It has minimal donor-site morbidity, because the rectus abdominis muscle is preserved as a whole, and it accommodates pregnancy in female patients. Simultaneous elevation of this flap during preparation of the recipient site makes it possible to complete surgery in a shorter time than with the scapular flap. Furthermore, a considerable amount of the superficial or deep fatty layer can be removed primarily, making a bulky flap into a thinner one. This flap also allows the use of a large transverse abdominal ellipse of skin, fat, and Scarpa's fascia with abdominoplasty closure. Conversely, it requires a technically difficult dissection of the muscle perforator and skin grafting of donor defects in patients with a large dermal-fat flap. Also, additional minor operations may be necessary to reduce fat volume around the perforator. Ultimately, the deep inferior epigastric perforator adiposal flap seems to be suitable for craniofacial contouring surgery. It is especially indicated for use in children and female patients who are expecting to have children.  相似文献   

11.
A rare case of nasal clefting was presented to illustrate and emphasize the following points: The workup of nasal clefting should be complete to rule out associated deformities. Marked improvement may be noted with normal growth during the first few years of life. The surgical procedure employed a primary V-Y flap harvested from the central excess of nasal skin based on a very thin vascular area at the nasal columella. At this primary procedure, the flap was telescoped on itself to provide fullness in the nasal tip area. It was also split, and two transposition flaps were inset into the gap left behind by rotating the ala into normal position. The donor area of the V-Y flap provided easy access to the intercanthal area so that the excess skin on the bridge of the nose could be reduced. Two subsequent minor procedures were required for adjusting irregularities in the tip.  相似文献   

12.
Contaminant-related stress on aquatic biota is difficult to assess when lethal impacts are not observed. Diatoms, by displaying deformities (teratologies) in their valves, have the potential to reflect sub-lethal responses to environmental stressors such as metals and organic compounds. For this reason, there is great interest in using diatom morphological aberrations in biomonitoring. However, the detection and mostly the quantification of teratologies is still a challenge; not all studies have succeeded in showing a relationship between the proportion of abnormal valves and contamination level along a gradient of exposure. This limitation in part reflects the loss of ecological information from diatom teratologies during analyses when all deformities are considered. The type of deformity, the severity of aberration, species proneness to deformity formation, and propagation of deformities throughout the population are key components and constraints in quantifying teratologies. Before a metric based on diatom deformities can be used as an indicator of contamination, it is important to better understand the “ecological signal” provided by this biomarker. Using the overall abundance of teratologies has proved to be an excellent tool for identifying contaminated and non-contaminated environments (presence/absence), but refining this biomonitoring approach may bring additional insights allowing for a better assessment of contamination level along a gradient. The dilemma: are all teratologies significant, equal and/or meaningful in assessing changing levels of contamination? This viewpoint article examines numerous interrogatives relative to the use of diatom teratologies in water quality monitoring, provides selected examples of differential responses to contamination, and proposes solutions that may refine our understanding and quantification of the stress. This paper highlights the logistical problems associated with accurately evaluating and interpreting teratologies and stimulates more discussion and research on the subject to enhance the sensitivity of this metric in bioassessments.  相似文献   

13.
Relevant statistical modeling and analysis of dental data can improve diagnostic and treatment procedures. The purpose of this study is to demonstrate the use of various data mining algorithms to characterize patients with dentofacial deformities. A total of 72 patients with skeletal malocclusions who had completed orthodontic and orthognathic surgical treatments were examined. Each patient was characterized by 22 measurements related to dentofacial deformities. Clustering analysis and visualization grouped the patients into three different patterns of dentofacial deformities. A feature selection approach based on a false discovery rate was used to identify a subset of 22 measurements important in categorizing these three clusters. Finally, classification was performed to evaluate the quality of the measurements selected by the feature selection approach. The results showed that feature selection improved classification accuracy while simultaneously determining which measurements were relevant.  相似文献   

14.
The injuries to the lower extremities seen in a surgical office may be classified as contusions, lacerations, sprains, lesions of tendons and their sheaths, involvement of bursae, chronic muscle fatigue, infections and deformities of the nails, leg ulcers, and fractures of the ankle, foot and toes.The treatment of these conditions in an office will vary under different circumstances, but one should be guided by certain fundamental rules. Contusions are best treated by the application of elastic compression bandages. Extensive lacerations should be explored under local anesthesia with the tourniquet in place, injured tissue excised, and the wound sutured. Ankle sprains should be strapped. Immediate hospitalization must be considered in all moderate to severe initial sprains to the knee. Lesions of bursae usually respond to the injection of hydrocortisone preparations. The same treatment is used in chronic muscle fatigue, plus immobilization of the part. Chronic recurrent infection and deformities of the nails are treated by removal of the nail under local anesthesia. Fractures of the ankle, the foot and toes may be reduced under local anesthesia and a cast applied. If further swelling is feared, the patient should be put in hospital immediately.  相似文献   

15.
Advances in head and neck reconstruction   总被引:5,自引:0,他引:5  
Head and neck deformities, which can be caused by trauma, congenital defects, infections, or neoplasms, produce a stereotypical constellation of functional and aesthetic deficits, depending on the specific anatomic region. These deformities can be classified into six major anatomic categories: intraoral, mandibular, midfacial, cranial base, cutaneous, and scalp. This article presents a reliable approach to the reconstruction of these six areas that is used at the University of Texas M. D. Anderson Cancer Center. The emphasis is on an analysis of the unique functional and aesthetic problems presented by each of these specific anatomic lesions, and the reconstructive options are selected to maximize outcomes. The problems and limitations of current methods are discussed, and areas of potential development are explored.  相似文献   

16.
Correction of secondary cleft lip deformities   总被引:2,自引:0,他引:2  
Stal S  Hollier L 《Plastic and reconstructive surgery》2002,109(5):1672-81; quiz 1682
Learning Objectives: After studying this article, the practitioner should be able to (1) describe the common secondary deformities of the cleft lip, (2) determine the appropriate timing for surgical intervention to correct the deformities, and (3) determine the best method of addressing each of the individual secondary deformities of the cleft lip. Secondary deformities are common in children born with a cleft lip and palate. Patients with cleft lip deformity will undergo multiple surgical procedures early in life, so it is imperative to prioritize treatment of their secondary deformities and minimize the number of interventions needed. Of the many approaches used to correct these problems, surprisingly few work well consistently. As with all plastic surgery, the timing and procedure should be predicated on the severity of the deformity.  相似文献   

17.
BACKGROUND: Agnathia is a rare malformation characterized by the absence of the mandible. METHODS: A male rhesus monkey with malformations was found dead and studied by internal examination, radiographs and histopathology. RESULTS: A case of a rare first branchial arch anomaly with agenesis of the mandible and tongue is presented. The animal also had visceral deformities. However, ears were normal in shape and only slightly low in position. The craniofacial malformations may reflect incomplete separation of the first branchial arch into its maxillary and mandibular processes. CONCLUSIONS: The association between the craniofacial and other corporal anomalies is unclear.  相似文献   

18.
Tubificid worms of the species Pomatothrix hammoniensis with characteristic, but hitherto unknown, deformities are described from four bays and fjords of Lake Vänern, Southern Sweden. These worms are easily recognized, since their chaetae are grotesquely enlarged distally, others are strongly serrated or deeply split, etc. These deformities are clearly associated with pollutants, since the limited areas of the lake in which they occur have long been under severe stress from industrial and municipal wastes, especially from nearby pulp mild and chlor-alkaline industries from which mercury compounds are known to emanate. Lake Vänern belongs to the most mercury-polluted major lakes of the world (Håkansson, 1976) with sediment concentrations of up to 10 000 ng Hg g?1 dry weight (natural back-ground value about 30 ng g?1 dry weight). The Kendall Rank statistical test showed a highly significant correlation (τ = 0.87; S = 14) between the incidence of deformities and mercury deposits in the lake. Zinc and cadmium are also deposited in large concentrations in the lake and there are also a variety of chlorinated organic compounds in the waste water about which we know little at present. It is speculated that synergistic effects between contaminants may be responsible for the deformities. It is likely that the observed deformities are mainly of phenotypic origin, since aberrant young specimens are uncommon.  相似文献   

19.
One of the most important problems of fish aquaculture is the high incidence of fish deformities, which are mainly skeletal. In this study, genetic parameters on gilthead seabream (Sparus aurata L.) for skeleton deformities at different ages (179, 269, 389, 539 and 689 days) and their correlations with growth traits were estimated, as were as their genotype × environment interactions (G × E) at harvesting age. A total of 4093 offspring from the mass spawning of three industrial broodstocks belonging to the PROGENSA® breeding programme were mixed and on‐grown by different production systems in four Spanish regions: Canary Islands (tanks and cage), Andalusia (estuary), Catalonia (cage) and Murcia (cage). Parental assignment was inferred using the standardized SMsa1 microsatellite multiplex PCR. From three broodstocks, 139 breeders contributed to the spawn and a total of 297 full‐sibling families (52 paternal and 53 maternal half‐sibling families) were represented. Heritabilities at different ages were medium for growth traits (0.16–0.48) and vertebral deformities (0.16–0.41), and low for any type of deformity (0.07–0.26), head deformities (0.00–0.05) and lack of operculum (0.06–0.11). The genetic correlations between growth and deformity traits were medium and positive, suggesting that to avoid increasing deformities they should be taken into account in breeding programmes when growth is selected. The G × E interactions among the different facilities were weak for length and deformity and strong for growth rate during this period. These results highlight the potential for the gilthead seabream industry to reduce the prevalence of deformities by genetic improvement tools.  相似文献   

20.
Pathophysiology of cleft lip muscle   总被引:1,自引:0,他引:1  
Although attention has been focused for decades on the correction of cleft lip deformities, our knowledge about the etiology of such deformities has remained presumptive. Sixty-six muscle biopsy specimens from cleft lip infants were obtained at the time of primary closure. Histochemical stains, histographic analysis, and electron microscopy were performed. A nonneurogenic muscle atrophy was seen that varied in severity, with muscle fibers near the cleft being the most atrophic and disorganized. Muscle fibers stained with the modified Gomori trichrome technique also demonstrated "ragged red" fibers typical of a mitochondrial myopathy. Electron microscopy confirmed large accumulations of mitochondria distorting the fibrils. These mitochondria also were increased in size and densely packed with cristae. This study thus demonstrates that the muscles in cleft lip deformities are not normal. Instead, they reflect either myopathy in the facial mesenchymal mitochondrion or at least a delay in maturation. We hypothesize that some of the morphologic deformities associated with cleft lip may cause a failure of mesenchymal reinforcement of the facial processes at a critical time in development.  相似文献   

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