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1.
A numerical taxonomic study using 75 characters was performed with 132 strains of gram-negative, nonmotile, nonfermentative bacteria selected on the basis of lack of motility and Gram reaction among 1,200 cultures isolated during aerobic storage of lamb carcasses. At the 80% similarity level (SSM), eight clusters were formed. Strains in clusters 1 to 6 could be identified as members of the family Moraxellaceae and, more specifically, as members of the Psychrobacter-[Moraxella] phenylpyruvica subgroup. Of these strains, clusters 1 and 2 (88 strains) were identified as [Moraxella] phenylpyruvica and cluster 3 (15 strains) was identified as Psychrobacter immobilis. Clusters 4, 5, and 6 were not identifiable with any species. Clusters 7 and 8 consisted of 14 strains considered nonmotile variants of Pseudomonas fragi. The highest separation indices corresponded to acid production from certain carbohydrates (melibiose, L-arabinose, and cellobiose). Although strains of Psychrobacter-Moraxella clusters were relatively frequently identified at the completion of slaughter, very few cultures were detected on spoiled carcasses. It appears, therefore, that this group of organisms has only low spoilage potential.  相似文献   

2.
A numerical taxonomic study using 75 characters was performed with 132 strains of gram-negative, nonmotile, nonfermentative bacteria selected on the basis of lack of motility and Gram reaction among 1,200 cultures isolated during aerobic storage of lamb carcasses. At the 80% similarity level (SSM), eight clusters were formed. Strains in clusters 1 to 6 could be identified as members of the family Moraxellaceae and, more specifically, as members of the Psychrobacter-[Moraxella] phenylpyruvica subgroup. Of these strains, clusters 1 and 2 (88 strains) were identified as [Moraxella] phenylpyruvica and cluster 3 (15 strains) was identified as Psychrobacter immobilis. Clusters 4, 5, and 6 were not identifiable with any species. Clusters 7 and 8 consisted of 14 strains considered nonmotile variants of Pseudomonas fragi. The highest separation indices corresponded to acid production from certain carbohydrates (melibiose, L-arabinose, and cellobiose). Although strains of Psychrobacter-Moraxella clusters were relatively frequently identified at the completion of slaughter, very few cultures were detected on spoiled carcasses. It appears, therefore, that this group of organisms has only low spoilage potential.  相似文献   

3.
目的:探讨高强度聚焦超声(high intensity focused ultrasound,HIFU)治疗子宫肌瘤的临床疗效及其安全性。方法:回顾性分析我院2007年1月~2011年1月300例采用高强度聚焦超声治疗的子宫肌瘤患者的临床资料,比较分析治疗前后瘤体大小、病灶内部回声、临床症状改善情况、血流的变化及超声造影图像改变。结果:HIFU治疗后1、3、6及12个月,瘤体体积均较治疗前显著缩小(P〈0.05),显效率80.33%(241例),有效率19.33%(58例),无效率0.33%(1例),肌瘤所致的临床症状减轻或消失,瘤体内部回声增强,彩色血流均消失,超声造影瘤体内无灌注。治疗期间,患者出现治疗部位疼痛、骶尾部酸胀及肛门坠胀,治疗结束时症状消失;治疗过程中出现腿部疼痛、麻木症状,经过重新定位后症状消失,少数出现阴道少量流血,给予止血药;治疗后出现血尿,经大量喝水排尿后消失。结论:HIFU治疗子宫肌瘤是安全有效的,在妇科领域便于推广。  相似文献   

4.
The removal of seeds of the exotic shrub Mimosa pigra from the ground beneath a thicket of the plant and from the open floodplain surrounding the thicket was studied experimentally. Seeds placed beneath the canopy of the M. pigra thicket were taken predominantly by vertebrates (probably omnivorous rodents) while those on the open floodplain were taken predominantly by ants. After 14 days exposure with no barriers to seed removal, less than half of the seeds placed in either habitat had disappeared. Of the seeds that were removed, over 75% had disappeared from both habitats within 5 days. It is unlikely that post-dispersal seed predation appreciably inhibits the spread or maintenance of stands of this weed in tropical Australia.  相似文献   

5.
Older monkeys of the Sulawesian species Macaca nigra spontaneously develop a lesion in the pancreatic islets of Langerhans in which there is deposition of amyloid and gradual degeneration of all cells, which can lead eventually to development of diabetes mellitus. Islet cell antibodies (ICA), formed in response to the release of cellular antigens, can be used to detect the islet lesion and to monitor the progression of each monkey toward diabetes. Numerous M. nigra and one M. tonkeana in captivity have been tested, but it is unknown whether the islet lesion occurs in monkeys in their natural habitat of Sulawesi. Blood samples collected from M. maurus, M. tonkeana, and hybrid M. maurus/tonkeana were assayed for ICA. When all monkeys were considered together, 33% had ICA positive against beta cells and 14% had ICA positive against alpha and/or D cells. Appearance of ICA in blood of males was virtually the same as in females. These results are similar to those found in M. nigra examined in captivity. Since all Sulawesian species share a common genetic heritage, these results would support the appearance of this lesion in their natural habitat. Cause(s) for formation of the lesion and eventual development of diabetes are unknown. There may be genetic factors or genetic predisposition to environmental factors. If environmental factors are responsible, then they must be present not only in the wild, but either carried with the monkeys or universally available, since M. nigra born in captivity also develop the lesion and diabetes after physical maturity at ca. 7+ years.  相似文献   

6.
Large proteoglycan monomers and small dermatan sulfate proteoglycans were extracted from explants of bovine articular cartilage with increasing (0-4 M) concentrations of guanidinium chloride (GuHCl). The first extractions were followed by a second extraction with 4 M GuHCl. The amount of proteoglycans extracted in the first buffer depended on the GuHCl concentration. At low concentrations of GuHCl, a relatively high amount of small proteoglycans was obtained. Fifty percent of the small proteoglycans was extracted in buffer with 0.85 M GuHCl, while 2.0-2.2 M GuHCl was needed to extract half of the large proteoglycans. Immediately after synthesis, 35S-labeled large proteoglycans were extracted much easier (50% at 1.4 M GuHCl), and those extracted at low concentrations of GuHCl were less capable of aggregation with hyaluronic acid. After 7 days of 'chase' these differences between endogenous and 35S-labeled proteoglycans had disappeared.  相似文献   

7.
The sensitivity of seven bacterial species inoculated on to sterile poultry meat and irradiated under various atmospheres (air, CO2, vacuum and nitrogen) was investigated. The irradiation sensitivities of Streptococcus faecalis and Staphylococcus aureus were unaffected by atmosphere. The other micro-organisms ( Pseudomonas putida, Salmonella typhimurium, Escherichia coli, Moraxella phenylpyruvica and a Lactobacillus sp.) were more sensitive (their D10 values decreased) when irradiated in atmospheres other than air. In general, a vacuum or CO2 atmosphere during irradiation was found to have the most lethal effect. Plating media were found to have a significant effect on the recovery of irradiated E. coli and Salm. typhirium.  相似文献   

8.
In three patients with long-standing vascular malformations of the face and scalp, radial forearm free flaps were transferred after a near-total excision of the lesion. All patients had typical high-flow malformations with thrill and bruit. The onset and progression of the malformations were analyzed through clinical and histologic studies. After free flap transfer, the vascular malformations were followed up grossly and histologically for between 4 and 9 years. There was no recurrence of arteriovenous malformation after free flap transfer. The portion of the residual lesion adjacent to the transferred free flap disappeared, and the remaining discoloration also vanished grossly. Histologic comparison of immediate postoperative and 4-month postoperative specimens from the margin and residual lesion using Victoria blue staining showed that the typical preoperative findings for arteriovenous malformation-an intermingling of thick-walled vessels with abundant elastic fibers and thin-walled vessels without elastic fibers-had undergone change, resulting in the disappearance of the thick-walled vessels and leaving only homogeneous, thin-walled vasculature. The highly vascularized free flap, which does not contain abnormal fistulas, impacted the histologic change of the arteriovenous malformation by blocking the vicious cycle of ischemia and anatomic replacement of disfigured skin and subcutaneous tissues.  相似文献   

9.
Reactive gliosis, observed in numerous pathological states, leads to the formation of a glial scar that is believed to impede axonal regeneration. Astrocyte reactivity can be initiated both in vitro and in vivo by various cytokines. Thus, the aim of this study was to investigate if suramin, a polysulfonated napthylurea that has been shown to inhibit the binding of many different cytokines to their cell surface receptors, could attenuate the glial response after brain injury. A single dose of suramin (5 μl, 75 μM) or saline vehicle was injected intracerebrally through the same needle used to make the stab wound at the time of lesioning. Suramin-treated animals showed an obvious reduction in several parameters of CNS inflammation: cellular proliferation, GFAP levels, and tenascin-C immunoreactivity were reduced in suramin-treated as compared to control animals at early time points. GFAP immunoreactivity was strikingly reduced at 3 days after injury, as confirmed by Western blot analysis. This reduction was transient, however, in that the difference in GFAP expression between suramin-treated and control animals was less apparent at 7 days and had disappeared by 30 days after injury. Likewise, fewer BrdU-positive cells were noted in treated versus control tissue at 1 and 3 days, but this difference was not significant by 7 days. Moreover, tenascin immunoreactivity was significantly diminished at 24 h as confirmed by Western blot analysis in suramin-treated lesion areas, which is analogous to our observations that suramin can antagonize tenascin expression by cultured astrocytes treated with bFGF. In addition, examination of the corpus callosum of saline-treated animals 30 days post-trauma revealed a disruption of the fiber tract within the lesion site, while suramin-treated animals displayed numerous fibers spanning the lesion. These results demonstrate that a single injection of suramin transiently inhibits the gliotic response, which may be sufficient to ameliorate subsequent tissue damage.  相似文献   

10.
Three female and 2 male adult laboratory-reared squirrel monkeys (Saimiri sciureus) that previously had been inoculated with Leishmania (Leishmania) donovani and had recovered from experimental visceral leishmaniasis were each inoculated intradermally at the dorsal base of the tail with 2.2 x 10(7) culture-derived promastigotes of Leishmania (Viannia) panamensis. The progression and regression of subsequent lesions were examined for 36 wk in all 5 monkeys after which 3 of the monkeys were killed (1 with a primary lesion and all with satellite lesions) and the 2 surviving monkeys (1 with primary lesion and both with satellite lesions) were treated with 104 mg/kg/day of meglumine antimoniate for 10 days. All of the monkeys developed a primary lesions at the site of injection of the parasite and later developed satellite lesions peripheral to the primary nodule. The primary lesions had disappeared from 3 of the 5 monkeys by 36 wk, whereas satellite lesions persisted on all at this time. Satellite lesions were present at 52 wk after treatment and persisted for 169 wk in the 2 surviving monkeys. The histopathologic appearance of the lesions was characterized as granulomatous inflammation. Our results indicated that squirrel monkeys that had recovered from visceral leishmaniasis remained susceptible to infection with L. (V). panamensis.  相似文献   

11.
The effects of high temperatures (46 to 50 degrees C) on the production of F pili by Escherichia coli were studied by electron microscopy. Attached F pili rapidly disappeared at 48 and 50 degrees C but not at 46 degrees C. Free pili were not denatured at these temperatures. The pili that disappeared from the cells at 50 degrees C did not appear as free pili in the culture supernatant fluid, indicating that the pili had retracted to the cell surface or into the cell. The adsorption of either R17 phage or F pili antibody to the sides of pili prevented retraction. The disappearance of pili was accompanied by a loss in the ability to adsorb R17 phage but not M13 phage, suggesting that the tip of a pilus remains exposed after retraction.  相似文献   

12.
A. Imaoka    M. Ueno    J. Kihara    S. Arase 《Journal of Phytopathology》2008,156(5):317-320
Rice cv. Sekiguchi‐asahi was identified as a lesion mimic mutant from cv. Asahi. This mutant showed light‐enhanced resistance to Magnaporthe grisea infection, inducing Sekiguchi lesion (sl) formation and tryptamine accumulation. To elucidate the role of chloroplasts on the activation of tryptamine pathway, the effect of some photosynthetic inhibitors on light‐dependant Sekiguchi lesion formation, tryptamine accumulation, and enzyme activities was investigated. When detached leaf blades which had been pretreated with Linuron, 1, 10‐Phenanthroline or Poly‐l ‐lysine were inoculated with M. grisea, respectively, Sekiguchi lesion formation and typtamine accumulation were suppressed even under light, suppressing gene expression of tryptophan decarboxylase and monoamine oxidase activity. On the other hand, catalase activity was significantly inhibited in control leaves infected with M. grisea under light, but kept at high level in chemical‐pretreated leaves. These results suggested that photosynthetic activity in chloroplasts was involved in inhibition of antioxidant sysytem and activation of tryptamine pathway responsible for light‐enhanced resistance in sl mutant to M. grisea infection.  相似文献   

13.
大鼠前庭内侧核在前庭—交感反应中的作用   总被引:1,自引:1,他引:0  
潘培森  张义声 《生理学报》1991,43(2):184-188
实验在氯醛糖和尿酯混合麻醉的大鼠上进行。在内脏大神经上记录刺激同侧前庭神经进入脑干处的交感反应。电刺激前庭神经可在同侧内脏大神经引出—明确的叠加反应,其平均潜伏期为45.8±6.98ms,时程为55.21±5.35ms。增加刺激强度,反应幅度也增加,但潜伏期不变。用前庭内侧核(NVM)的片层场电位作为指标并选择其相位倒转处作刺激点,可在同侧内脏大神经记录到潜伏期为32ms 的叠加反应,而同一动物刺激前庭神经入脑处时内脏大神经反应的潜伏期为43ms。在 NVM 头端损毁后,此前庭-交感反应明显减小,再损毁尾端 NVM 后,此反应消失。损毁 Deiters 核对前庭-交感反应无影响。这些结果表明 NVM在内脏大神经记录到的前庭-交感反应中是一重要的中继站。  相似文献   

14.
The kinetics of macrophage (M phi) recruitment to the peritoneum following the induction of acute inflammation by thioglycollate broth (TG) was evaluated after prelabeling resident M phi with the fluorescent cell tracking dye, PKH-1. Most of the PKH-1-labeled resident M phi disappeared from the recoverable peritoneal cell population within the first hour after injection of TG. This disappearance coincided with the inflammatory influx of neutrophils (PMNs) and was sustained for at least 5 days after administration of TG, although the PMN number had returned to resident levels by this time. PKH-1-labeled peritoneal M phi were observed again in most animals at 7 days after injection of TG. The number of labeled M phi recovered at 7 days was approximately twice the number of resident peritoneal M phi in control animals which did not receive the TG broth. These additional M phi may include progeny of either the resident M phi or other local M phi precursors, such as omental M phi, which were labeled by the PKH-1 injection.  相似文献   

15.
以多刺裸腹溞为受试生物,在较低(0.5×106 cells·mL-1)、中等(1.0×106 cells·mL-1)和较高(2.0×106 cells·mL-1)的斜生栅藻密度下研究了不同浓度(0、0.45、0.9、1.8、3.6、7.2 和14.4 mg·L-1)的布洛芬对多刺裸腹溞生命表统计学参数的影响.结果表明: 在较低和较高的食物密度下,布洛芬浓度分别对多刺裸腹溞的种群内禀增长率和生命期望具有显著性影响;但在3个食物密度下,布洛芬浓度对多刺裸腹溞的世代时间、净生殖率和总生殖率均无显著性影响.与对照组相比,在较低的食物密度下,暴露于0.45、0.9、3.6和14.4 mg·L-1布洛芬溶液中的多刺裸腹溞的种群内禀增长率显著降低;在较高的食物密度下,暴露于3.6 和14.4 mg·L-1布洛芬溶液中的多刺裸腹溞的生命期望显著延长.表明在较低的食物密度下,布洛芬对多刺裸腹溞的种群增长具有不利的影响;但在中等和较高的食物密度下其不利影响消失.在较高的食物密度下,布洛芬对多刺裸腹溞的存活具有促进作用;但在较低和中等食物密度下其促进作用并未出现.布洛芬对多刺裸腹溞部分生命表统计学参数的影响因食物密度的不同而异.  相似文献   

16.
T Wada  X L Qian  M I Greene 《Cell》1990,61(7):1339-1347
We have used cross-linking reagents on cell lines expressing both p185neu and EGFR. The lysates of the cells were precipitated with anti-p185neu or anti-EGFR antibodies. These precipitates included a high molecular weight complex that was identified as an EGFR-p185neu heterodimer. Heterodimerization was found to be induced by exposure to EGR. The EGFR of these cells displayed three affinity states for EGF: low (Kd, approximately 10(-9) M), high (Kd, 10(-9) to 10(-10) M), and very high (Kd, 10(-11) M), as determined by Scatchard analyses. Relatively small levels of EGF had a dramatic biological effect on cells expressing very high affinity EGFR. The very high affinity EGFR disappeared after the cells were treated with anti-p185neu monoclonal antibodies that selectively down-regulated p185neu. EGF and TPA had differential effects on down-modulation of the EGFR in cells that express either one or both species of receptor proteins.  相似文献   

17.
The lytic effects of serum from a non-immunized rabbit on epimastigotes of Trypanosome cruzi were studied by electronmicroscopy. The first detectable change was the appearance of a fuzzy deposit over the whole surface of the epimastigote. Soon after this, pellicular microtubules disappeared without change of axonemal microtubules. Circular lesions were observed by negative staining, corresponding to the lesion of antibody-mediated lysis caused by complement.  相似文献   

18.
The population dynamics of Mus minutoides and Steatomys pratensis are virtually unknown. These two species were live-trapped over a 12-month period in a subtropical grassland in Swaziland. Numbers of M. minutoides were relatively high in winter, declined in spring and the population disappeared in summer and autumn. By contrast, numbers of S. pratensis increased gradually from winter to summer and reached a peak in autumn. There were no differences between the mean weights of male and female M. minutoides and S. pratensis. There were, however, seasonal differences in the mean weight of male S. pratensis, with highest weights recorded in summer. Individuals of both species came into breeding condition in spring (October–November). Reproduction had ceased by the end of autumn (April–May). Monthly survival rates of M. minutoides were highest in winter, but did not vary seasonally in S. pratensis. Burning had a pronounced effect on the distribution of S. pratensis. Steatomys pratensis individuals selected recently burnt but revegetated areas over unburnt areas. The effect of burning on the M. minutoides population is difficult to assess, as this species disappeared shortly after the fire.  相似文献   

19.
This study describes a case of pituitary-dependent Cushing's syndrome where standard biochemical and radiological techniques were discordant in localizing the origin of the autonomous adrenocorticotropic hormone (ACTH) hypersecretion in the pituitary. Hormonal evaluation suggested a pituitary genesis for the disease, but both sellar computed tomography and cranial magnetic resonance (MR) were unable to give clear-cut evidence for a pituitary neoplasm. Simultaneous and bilateral inferior petrosal sinus sampling (SBIPS) correctly identified the left side of the pituitary gland as the source of autonomous ACTH production. One year later, the shaded signs of a pituitary lesion in the left side of the gland were seen with MR imaging, and a 0.5-cm in height adenoma was surgically removed. At the 2-year follow-up the patient's symptoms had completely disappeared, and her menses were restored. In this case, SBIPS correctly diagnosed the presence of an ACTH-secreting pituitary microadenoma one year before shaded signs of the pituitary lesion appeared with MR imaging. This is a clear-cut demonstration of the accuracy of the SBIPS technique in localizing small pituitary lesions.  相似文献   

20.
尖顶羊肚菌对急性酒精性胃黏膜损伤保护作用研究   总被引:3,自引:0,他引:3  
研究尖顶羊肚菌菌丝体水提液对酒精引起的大鼠急性胃黏膜损伤的保护作用。以95%乙醇诱导的大鼠胃黏膜损伤为模型,测定各组胃黏膜损伤指数,并测定胃黏膜超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱甘肽(GSH)含量,采用幽门结扎法,测定大鼠胃酸、胃蛋白酶与胃黏液分泌的量。结果表明羊肚菌中、高剂量能明显降低胃黏膜损伤指数(p<0.05);羊肚菌不能抑制胃酸的分泌(p>0.05),但是能增加胃蛋白酶与胃黏液的分泌(p<0.05);95%乙醇能引起胃黏膜SOD活性与GSH的降低,MDA含量的增加,给予羊肚菌能明显抑制这一现象。结果说明羊肚菌对急性酒精性胃黏膜损伤的保护作用是与增加胃黏液分泌与提高机体抗氧化能力有关。  相似文献   

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