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1.
Sulfamylon (mafenide) solution, a potent experimental topical antimicrobial, is used in our burn unit to treat burn wounds both before and after skin grafting. The importance of fibrin to early graft adherence prompted this in vitro study of the effect of Sulfamylon upon fibrin clot. Assessing fibrinolysis by in vitro proteolysis of [125I] fibrin monomers, Sulfamylon, at relevant clinical concentrations, produced dose-related inhibition of streptokinase-mediated fibrinolysis. In addition, Sulfamylon had no intrinsic fibrinolytic activity. This antifibrinolytic property of Sulfamylon solution may, in vivo, protect against early graft loss when used on burn wounds and other potentially contaminated graft sites.  相似文献   

2.
An in vivo comparison of topical agents on wound repair.   总被引:2,自引:0,他引:2  
Selection of the ideal antiseptic or antimicrobial treatment for contaminated wounds remains a controversial decision. Clinical decisions are often made on the basis of in vitro studies and personal preference. Although topical solutions are widely used, their comparative in vivo effects on wound healing are largely unreported.A porcine wound model was used to compare five commonly used topical agents-5% mafenide acetate (Sulfamylon solution), 10% povidone with 1% free iodine (Betadine), 0.25% sodium hypochlorite ("half-strength" Dakin), 3% hydrogen peroxide, and 0.25% acetic acid-with a control group. Reepithelialization, angiogenesis, neodermal regeneration, fibroblast proliferation, collagen production, and bacterial colony counts were analyzed at 4 and 7 days after wounding (n = 4).Reepithelialization was not significantly influenced among the various treatment modalities tested. Sulfamylon and Dakin solutions significantly increased neodermal thickness (p < 0.05), whereas hydrogen peroxide and acetic acid significantly inhibited neodermal formation (p < 0.001). All treatments except hydrogen peroxide significantly increased fibroblast proliferation. Sulfamylon and Betadine significantly enhanced angiogenesis (p < 0.05). Sulfamylon proved most effective in maintaining an aseptic environment while concomitantly increasing angiogenesis, fibroblast proliferation, and dermal thickness compared with control.These data show that selection of a particular topical treatment can affect various aspects of wound repair in an animal model. These results suggest that the selection of topical treatments in the clinical setting should be carefully tailored to match unique wound situations and therapeutic endpoints.  相似文献   

3.
Thirteen Rocky Mountain bighorn sheep (Ovis canadensis canadensis) with clinical signs of psoroptic scabies were captured in Wyoming. Signs included droopy ears, depilation on the head and neck, and exudate in the ears. Mites were identified as either Psoroptes cervinus or P. equi. Two ewes with scabies at the time of original capture had no clinical signs of mite infection 1 and 2 yr later.  相似文献   

4.
In 1995, ears of a experimental inbred (CG59-2) containing a synthetic Bacillus thuringiensis Cry IA (b) gene driven by PEPC, pith and pollen promoters and artificially infested with Ostrinia nubilalis (Hübner) larvae in small plot studies were free from insect damage, whereas 40-50% of the corresponding non-Bt inbred ears were damaged. Bt inbred ears that were inoculated with Aspergillus flavus Link and Fusarium proliferatum T. Matsushima (Nirenberg) or exposed to natural mold inoculum after infestation with O. nubilalis were free of visible signs of mold, as compared with approximately 30-40% of the non-Bt ears similarly treated. Results in 1996 using the same inbred with a single allele dose of the Bt gene showed similar trends. Mean total fumonisin levels for non-Bt versus Bt inbred ears were not significantly different (2.8 versus 0.8 ppm, respectively) in 1996. In paired hybrid studies run in 0.4-ha (1-acre) fields, an event 176 Bt hybrid had significantly lower amounts of damage and signs of Fusarium spp. mold, but not fumonisin, compared with a corresponding non-Bt hybrid from 1996 to 1998. However, two hybrid pairs that contained either MON810 or Bt11 constructs examined in similar fields at the same site had lower levels of fumonisin in both 1997 (30- to 40-fold) and 1998. High intrafield variability in insect infestation and presence of Helicoverpa zea (Boddie) in Bt hybrids was apparently responsible for fewer significant differences in fumonisin levels in 1998. Similar trends for all three hybrid pairs were noted in small plot trials at another site. Incidence of other ear pests or insect predators varied as much among non-Bt hybrids as they did for Bt/non-Bt hybrid pairs.  相似文献   

5.
Affinity chromatography of carbonic anhydrase   总被引:1,自引:0,他引:1  
An insoluble support for affinity chromatography of carbonic anhydrase has been prepared by coupling Sulfamylon (p-aminomethylbenzene sulfonamide) to Sepharose 4B. Carbonic anhydrase binds to Sulfamylon-Sepharose very strongly and can be eluted under mild conditions by the addition of enzyme inhibitors. The gel was used to purify carbonic anhydrase from human erythrocytes and to separate isozymes B and C. It was also employed to separate native enzyme from modified carbonic anhydrases. The apoenzyme and the carboxymethyl enzyme of human carbonic anhydrase B were both isolated by this method.  相似文献   

6.
If the ears of moths exist primarily to detect the echolocation calls of hunting bats, endemic moths in bat-free areas (i.e., species that have evolved in the absence of the selection pressure maintaining ears) should exhibit signs of deafness. Noctuid moths from the Pacific islands of French Polynesia, a site that has never possessed bats, were sampled and electrophysiologically analysed to test this hypothesis. The auditory sensitivities of seven endemic and twelve immigrant species, captured from the islands of Tahiti, Moorea, and Hiva Oa, were compared. Both classes possess neurally responsive ears, but endemics are significantly deafer than immigrants at frequencies above 35 kHz. This form of deafness is similar to other moths presumably released from the selection pressure of bat predation. I conclude that endemic moths at this site exhibit preliminary stages of deafness and that, considering their small cellular investment, ears in moths will be lost at a slower rate than more complex sensory organs.  相似文献   

7.
Four corn (Zea mays L.) hybrids were grown in 1977 and 1978 and inoculated with Aspergillus flavus Link 20 or 40 days after silking. Inoculation methods included needle, knife, and multiple-puncture injury to the kernels. The level of aflatoxin contamination, insect damage to the ear, and the percentage of ears having visible greenish A. flavus Link-type mold were determined. Differences among hybrids were not significant for any of the three characteristics measured, although aflatoxin levels of the early-maturing, loose-husked hybrids were approximately twice as high as those of two later-maturing, tight-husked types. Differences among treatments for insect damage rating were not statistically significant. Delaying inoculation until 40 days after silking significantly reduced the aflatoxin contamination level of samples harvested at maturity. Fewer than one-half the ears inoculated at 40 days after silking (35.3%) exhibited visible signs of infection compared with ears inoculated 20 days after silking (82.9%). The needle inoculations were less effective in eliciting aflatoxin production (163 μg/kg and 45.1% visibly infected ears) than were knife (202 μg/kg and 61.8% visibly infected ears) and multiple puncture (305 μg/kg and 70.4% visibly infected ears) methods of inoculation.  相似文献   

8.
A mentally retarded child with an extra small bisatellited acrocentric chromosome is described. The patient exhibited rather unspecific clinical signs such as strabismus, marked facial asymmetry, broad and prominent nasal bridge, hypertelorism, Brushfield's spots, malformed ears with atresia of the external auditory canal on the right side. Giemsa banding (R and G methods) did not allow a clear cytogenetic identification of the extra-chromosome. A tentative interpretation of the cytogenetic aberration as a trisomy of the proximal part of the long arm of chromosome 13 is discussed.  相似文献   

9.
An increased incidence and severity of a brownish coloration of hair has been observed around the nose and on the ears of female rats that were chronically exposed to 60-Hz electric fields. Microscopic examination of the colored areas revealed a red-brown globular deposit on hair shafts in affected areas without signs of physical injury.  相似文献   

10.
The normal pattern of maize floral development of staminate florets on the terminal inflorescence (tassel) and pistillate florets on the lateral inflorescences (ears) is disrupted by the recessive mutation tassel seed 2. Tassel seed 2 mutant plants develop pistillate florets instead of staminate florets in the tassel. In addition, the ears of tassel seed 2 plants display irregular rowing of kernels due to the development of the normally suppressed lower floret of each spikelet. The morphology of tassel and ear florets of the recessive maize mutant tassel seed 2 has been compared to those of wild-type maize through development. We have identified the earliest stages at which morphological signs of sex differentiation are evident. We find that sex determination occurs during the same stage on tassel and ear development. Early postsex determination morphology of florets in wild-type ears and in tassel seed 2 tassels and ears is identical.  相似文献   

11.
12.
Four groups of cotton rats, Sigmodon hispidus, were shown to be suitable secondary hosts for the viperid coccidium, Caryospora bigenetica, following oral inoculation of a mixture of oocysts and sporocysts. Swelling of the face, ears, and scrota and hemorrhagic ears were the predominant clinical signs and some cotton rats died in 3 of 4 experiments. Developmental stages of C. bigenetica were found in connective tissue components of the ear, nose, cheeks, anal skin, scrotum, and penile sheath of all cotton rats in which these tissues were examined. Additionally, developmental stages of C. bigenetica were found in connective tissue components of the following tissues examined from some cotton rats: tongue, lung, testicle, epididymis, rectum, base of the tail, footpad, and bone marrow. The present study shows that C. bigenetica can be pathogenic for cotton rats and demonstrates many new anatomic sites for developmental stages of this parasite in the secondary host.  相似文献   

13.
Full trisomy 22 in a newborn infant   总被引:1,自引:0,他引:1  
Karyotype 47,XY,+22 was found in a newborn infant with primitive and low-set ears, bilateral preauricular pit, broad nasal bridge, antimongoloid palpebral fissures, macroglossia, enlarged sublingual glands, cleft palate, micrognathia, clinodactyly of the fifth fingers, hypoplastic finger nails, hypoplastic genitalia, short lower limbs, bilateral sandal gap and deep plantar furrows. The child developed signs of congenital heart disease and died at the age of 10 weeks. Non-disjunction studies showed maternal origin (meiosis I) of the extrachromosome.  相似文献   

14.
Summary The first child of a mother with a balanced translocation (9;13) revealed a trisomy for the distal third of 13q. Clinical signs were microcephaly, hemangiomata, long incurved eyelashes, strabismus, enlarged bridge of the nose, abnormally long philtrum, high-arched palate, low set ears, hexadactyly of the four extremities, umbilical and inguinal hernias, neonatal respiratory distress, psychomotor and growth retardation. The proband presented also male pseudohermaphroditism and trigonocephaly. This last trait is the object of a discussion in which cases of partial trisomy 13q cited in the literature are considered for study of the incidence of this dyscephaly in this particular syndrome.  相似文献   

15.
In order to evaluate the central interferences on the auditory efficiency, the effect of contralateral masking noise on Critical Ratio (CR) has been studied in 14 normal ears (control group), in 12 ears with cochlear disorders and in 6 with retrocochlear lesion (acoustic neuromas); in all cases the impairment was unilateral, while the other ear was normal. CR values were calculated for 1 KHz pulsed tones (duration 500 ms, rise/fall 25 ms, duty cycle of 50%); the masking noise was a wide band (90-20,000 Hz) delivered at 40 dB SL. The results have demonstrated that in the presence of contralateral masking noise, CRs don't modify both in the normal ears and in those with retrocochlear disorder, whereas they increase, almost always, in ears with cochlear deafness. These results demonstrate that the involvement of central auditory pathways, because of contralateral noise, makes the auditory efficiency worse, only in ears with cochlear dysfunctions; this behaviour seems to confirm the peripheral origin of CR.  相似文献   

16.
The nutritive value of whole crop forage maize is influenced by the proportion of ears and stover in the whole crop and by the nutrient composition and digestibility characteristics of the plant parts. An experiment investigating the impact of variety, harvest date and year on the nutritive value of ensiled maize ears was carried out in three consecutive years (2007, 2008 and 2010). Nine different maize varieties were harvested at three different maturity stages (50, 55 and 60% dry matter (DM) content in the ears). After harvest, ears and stover were ensiled separately and afterwards nutrient composition and ruminal nutrient degradability (organic matter (OM), crude protein (CP) and non-fibre carbohydrates (NFC)) were analysed. Variety had a significant influence on content of CP and effective ruminal degradability (ED) of OM at low passage rates, whereas ED of CP and NFC was not affected by variety. In contrast, harvest date and year significantly influenced nutrient composition and ruminal degradability of ensiled maize ears. The content of NFC increased and the content of fibre components as well as ED of OM, CP and NFC declined with processing maturity of the maize plants. At a passage rate of 5% h?1, ED of OM declined from 75.9% to 68.4%, ED of CP from 82.5% to 73.8% and ED of NFC from 88.0% to 82.3% between the early and late harvest date. The results of this study indicate that the nutrient composition and ruminal degradability of ensiled maize ears are affected mainly by maturity stage at harvest and by year, whereas variety has only little influence.  相似文献   

17.
In most occasions the Turner's syndrome is diagnosed on the basis of severe growth retardation. But the possibility of an effective treatment of short stature requires earlier a diagnosis. Among the other signs, the importance of ORL signs is underestimated. A group of 30 patients has been analysed to determine their precise extension. The external ears are frequently prominent, low-set and/or posteriorly rotated. Frequency and chronicity of otitis media is highlighted by hypoacousy of the transmission type. The perception pathology is far less common and seems being independent of middle ear pathology. A abnormal development of the 1st branchial arch is likely to explain the auricular pathology in view of the frequently associated anomalies of the palate and the dental articulation. One must clearly consider the diagnosis of Turner syndrome in the case of chronic auricular pathology associated with low linear velocity in a young girl allowing for earlier diagnosis.  相似文献   

18.
Highland cattle with congenital crop ears have notches of variable size on the tips of both ears. In some cases, cartilage deformation can be seen and occasionally the external ears are shortened. We collected 40 cases and 80 controls across Switzerland. Pedigree data analysis confirmed a monogenic autosomal dominant mode of inheritance with variable expressivity. All affected animals could be traced back to a single common ancestor. A genome-wide association study was performed and the causative mutation was mapped to a 4 Mb interval on bovine chromosome 6. The H6 family homeobox 1 (HMX1) gene was selected as a positional and functional candidate gene. By whole genome re-sequencing of an affected Highland cattle, we detected 6 non-synonymous coding sequence variants and two variants in an ultra-conserved element at the HMX1 locus with respect to the reference genome. Of these 8 variants, only a non-coding 76 bp genomic duplication (g.106720058_106720133dup) located in the conserved region was perfectly associated with crop ears. The identified copy number variation probably results in HMX1 misregulation and possible gain-of-function. Our findings confirm the role of HMX1 during the development of the external ear. As it is sometimes difficult to phenotypically diagnose Highland cattle with slight ear notches, genetic testing can now be used to improve selection against this undesired trait.  相似文献   

19.
大麦产量构成模型   总被引:1,自引:0,他引:1  
通过产量构成法构建了适用于不同地区不同品种的大麦产量模拟模型.以南京、昆明、武汉3个地区各试验处理中不同大麦品种最适条件下的产量因素为基础,建立了最适条件下每株穗数相对值、每穗粒数相对值、千粒重相对值与累积光合有效辐射的回归方程,构建了实际条件下的不同大麦品种每株穗数、每穗粒数和千粒重与这三者在最适条件下的潜在值和实际条件下的水肥丰缺因子等变量的函数关系.模型较为全面地考虑了大麦品种生长发育的内外因素,内因主要体现为品种遗传特性(潜在的每株穗数、潜在的每穗粒数、潜在的千粒重和灌浆期因子),外因包括光合有效辐射和水肥丰缺因子.运用武汉、昆明、扬州3个地区不同品种、不同播期的田间试验资料对模型进行了测试和检验.结果表明,模型对大麦产量构成因子及理论产量的模拟效果较好,模拟值与观测值吻合度高,每株穗数、每穗粒数和千粒重相对误差(RE)绝对值的平均值分别为1.96%、1.88%和1.67%,对这三者及理论产量的模拟值和观测值进行y=x回归分析,相关系数(r)在0.9464~0.9987,相关性显著,说明模型具有较高的预测性和适用性.  相似文献   

20.
In the Origin of Maize Controversy, the Orthodox Teosinte Hypothesis (OTH; Beadle 1939, 1972; Iltis 1971), five key mutations change 2-ranked (distichous) ears of teosinte (wild Zea) with a single row of grains per rank to 4- to many-ranked (polystichous) maize ears with a double row of grains per rank. BUT teosinte ears are lateral to the 1° branch axes, maize ears, like their male homologues, the teosinte I° branch tassel spikes, terminal, an enigma long unrecognized, hence ignored. In the Catastrophic Sexual Transmutation Theory (CSTT; Iltis 1983b, 1987), now abandoned, the I° branch tassel (male) of teosinte (spikelets soft-glumed, paired, i.e., double-rowed per rank, as in maize ears), when brought under female hormonal control by branch condensation, becomes feminized into a maize proto-ear. BUT lateral ears should then have remained teosintoid (2-ranked, each rank with a single row of grains), yet are in fact double-rowed. Combining OTH and CSTT, the new Sexual Translocation Theory (STLT) is based on: first, the branching pattern of teosinte ear clusters (Cámara-H. & Gambino 1990), sequentially maturing, sympodially branching, typically Andropogonoid systems, called rhipidia (sing, rhipidium), where each higher order (younger) ear originates as a lateral branch of its lower order, earlier maturing predecessor; and second, on 3 or 4 key mutations [cupule reduction, softening of glumes, doubling of female spikelets], which, by projecting outward the grains, invited human domestication by making them accessible. Within each ear cluster, the earliest maturing, hence nutrient-monopolizing and largest ear would be selected, all younger ears, already nutrientinhibited, suppressed. As fewer, larger ears evolved, and branch internode condensation moved male tassels into female hormonal zones, homeotic conversions translocated female morphology to terminal male positions: first replacing each of the II° branch tassels, and ultimately the 1° branch tassel (male), with an ear (female). With this, now female structure in the apically dominant, hence most nutrient-demanding terminal position gradually suppressing all subsidiary ears on the 1° branch beneath it, mutations for polystichy (contingent on nutrient overload) were finally allowed to become expressed, and the multi-rowed maize ear (at first with an atavistic male tail) evolved. Favored by human selection, these increases in apical dominance by stepwise homeotic sexual conversions explain both archeological and morphological realities, but need to be harmonized with recent results of developmental genetics. Current evidence suggests that teosinte was first tended for its green ears and sugary pith by hunter-gatherers as an occasional rainy-season food in small “garden” populations away from its homeland, and not for its abundant grain-containing, hard fruitcases, which easily mass-collected but useless as food, are as yet unknown from the archeological record. A rare grain-liberating teosinte mutation (probably expressed in only one “founder” plant, a mazoid “Eve”), which exposed the encased grain for easy harvest, was soon recognized as useful, collected and planted (or self-planted). Thus maize was started on its way to a unique horticultural domestication that is not comparable to that of the temperate Old World mass-selected agricultural grains.  相似文献   

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