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1.
A method for the comparison of protein three-dimensional substructures was developed. The method employs the double dynamic programming method of Taylor & Orengo but identifies multiple local alignments rather than a single global alignment. A modification based on the Smith Waterman algorithm for sequence alignment enables the automatic identification and growth of the most structurally similar local alignments irrespective of length and composition. The method can also be used in a search mode to match substructures. Roughly five minutes is required to find all Greek-key motifs in a protein of 100 residues. Two novel globin folds have been detected using the method, the antibiotic protein colicin A and diphtheria toxin, neither of which have any functional relationship to the globins.  相似文献   

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A nonsteroidal antiinflammatory drug, 5-bromo-2-(4-fluorophenyl)-3-(4-methylsulfonylphenyl) thiophene (BFMeT), induced ileal ulcers in rats after oral administration, while no ulcers were observed after subcutaneous injection. The ileal ulcer formation in BFMeT-treated rats was examined to correlate the administration of cultures of Lactobacillus acidophilus or Bifidobacterium adolescentis with intestinal bacteria in the ileal contents and lipid peroxidation of the small intestinal mucosa. Ileal ulcers were observed in more than 85% of the rats treated with BFMeT at a dose of 1,000 mg/kg when they were given tap water as drinking water. The incidence of ulcer formation was repressed by giving culture supernatants of L. acidophilus or B. adolescentis as drinking water, but not by giving the cell suspension as drinking water. Gram staining of the ileal contents of normal rats revealed that 97% of the stained bacteria were gram-positive rods and only 1.5% were gram-negative rods. The percentage of gram-negative rods 72 hr after BFMeT administration was 49.8% and increased over 30-fold in BFMeT-treated rats. However, the percentage of gram-negative rods was 9.7 % or 16%, respectively, in rats taking culture supernatants of L acidophilus or B. adolescentis. In addition, thiobarbituric acid-reactive substances in the ileal mucosa increased significantly in the rats given tap water for 72 hr after BFMeT treatment, but not in rats given the culture supernatants of L. acidophilus or B. adolescentis. Since BFMeT induced an unbalanced intestinal microflora, the effect of antibiotic treatment on ulcer formation in rats was examined. The magnitude of the ulcer formation in the antibiotic-treated rats was, in decreasing order, metronidazole >none > kanamycin > a mixture (bacitracin, neomycin and streptomycin). These results suggest that the intestinal microflora plays an important role in ulcer formation and that a metabolite(s) of L. acidophilus and B. adolescentis inhibits ileal ulcer formation by repressing changes in the intestinal microflora and lipid peroxidation in BFMeT-treated rats.  相似文献   

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高怡斐 《冶金分析》2004,24(Z2):509-512
介绍了轴向试验机同轴度的测量和分类方法,该方法适用于拉伸、压缩或拉压的静态和动态加载单轴试验系统.  相似文献   

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A new method has been designed for direct measurement of the two-dimensional range of motion (ROM) of the finger. The two-dimensional method encompasses the postures imposed by various combinations of contraction and relaxation of the finger motors, so that an individual muscle injury or adhesion might be more easily detected. The figures and values obtained from the two-dimensional method are easier to interpret than those from conventional measurements, making the progress of the rehabilitated finger more apparent. Since the passive ROM cannot be evaluated by this method, it is a supplement rather than a substitution for the conventional range of motion evaluation for each joint. The drawback of the two-dimensional method is that it is more difficult to use than the conventional method.  相似文献   

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An in vitro test is described that simulates the in vivo fate of a denture adhesive, namely destruction, dilution, and dissolution of the adhesive, by repeated measurement of tensile bond strength for the adhesive in isotonic saline over time. The bond strengths were measured under two different settings of the testing machine. The main compositions of three denture adhesive pastes, Fittydent, Fixodent, and Super Poli-Grip and one powder adhesive, Super Wernet's, were determined by infrared spectroscopy. The tensile bond strengths of these adhesives and those of pure tragacanth gum were subjected to a three-way analysis of variance. The Fittydent and Super Poli-Grip adhesives exhibited the best results over time. The most appropriate of the described methods for testing denture adhesives seem useful; however, when seen in relation to the results of a published clinical study where the patients were asked to evaluate the retention and the duration of some of these adhesives, there are indications that the clinical validity of the method might be improved if paste adhesives are tested at temperatures above 35 degrees C.  相似文献   

8.
对取向电工钢SST(82)和SST(92)单片测试方法的差异进行分析,并对两者间的测量偏差进行量化评价。结果表明:SST(92)单片测试方法测量比总损耗较SST(82)平均偏高5.03%左右,这主要是因为SST(82)单片测试方法的有效磁路长度不固定,且离散性较大,而有效磁路长度主要跟单片磁轭有关。另外,直接测量试样磁场强度的H线圈方法由于规避了有效磁路长度的影响,可视为一种可靠的替代方法。  相似文献   

9.
采用全释放法和释放法对矫直后重轨外表面的残余应力分布进行了比较研究。结果表明重轨外表面的残余应力分布是极不均匀的。对于纵向残余应力而言,采用两种方法检测得到的结果在应力分布规律上趋于一致,但在残余应力幅值上存在很大差异;对于横向残余应力,则只有全释放法能够得到有效的结果。  相似文献   

10.
A hydraulically operated machine for applying well-defined forces to the knee joint is described. The measurement of anteroposterior as well as lateral and medial stability in the knee joint is based upon roentgenograms exposed while the forces are being exerted on the patient. The advantage of the radiological measuring method over methods using external measurements is the elimination of inaccuracies due to displacements of the soft tissues of the limb. The accuracy was evaluated by test/retest examination of 50 healthy subjects. The radiographs were measured at random after cessation of examinations in the gonylaxometer. The accuracy is +/- 1.2 nm for medial/lateral, +/- 2.4 nm for drawer sign. Diagnostically the difference between the two knees must exceed 2.0 nm (collateral instability) or 3.1 nm (drawer) to exceed standard values. The standard values for the different ligament laxities are given. The applied force to be used for evaluation of medial/lateral stability is recommended to be 9 kg, and for anteroposterior stability between 20 and 30 kg.  相似文献   

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王勃  胡冲  王杰  王月宇  李宁 《中国冶金》2021,31(2):50-54
涡流检测法是非常常用的金属材料缺陷检测的无损检测方法,为了改进传统涡流检测法难以微型化的不足,提出了一种新型涡流检测法,分别用小永磁体和高精度磁传感器代替了传统涡流检测法的激励线圈和接受线圈.通过试验和数值模拟相结合的研究方法,对新型涡流检测法的原理及检测效果进行了研究.结果表明,新型涡流检测法的检测原理可行,检测装置...  相似文献   

14.
To determine the long-term outcome of 12 youthful patients with lumbar disc herniation, who, at the time of surgery, were 15 years old and younger (mean age at operation 14.3 years), we assessed their current clinical condition (mean follow-up time 6 years) with a questionnaire inquiring about symptoms and disability, and radiologically with an MRI of the lumbar spine. Clinically, only five patients (40%) were totally asymptomatic and seven patients (60%) had recurring symptoms, both and disability. On MRI, seven patients (60%) had persistent stenosing changes at the operated disc levels and eight patients (65%) also had disc degeneration at other lumbar levels. Despite the symptoms and quite severe radiological findings, the long-term outcome was assessed as good or moderate in eleven patients (90%). As far as comparisons are reasonable, our results appear somewhat less favourable than those in two previous paediatric series, but they agree with those in two recent large series of adults.  相似文献   

15.
The acute effects of various doses of two selective serotonin reuptake inhibitors (fluoxetine and fluvoxamine) on thermal and electrical stimulation-induced pain were investigated in drug-naive Wistar rats. The hot-plate and the tail-flick test and the noxious-induced withdrawal test were used. The two drugs had no effects on heat-induced pain behavior. However, the two compounds enhanced the motor responses induced by noxious electrical stimulation. These data contrast to what is generally found for tricyclic antidepressants and suggest a modality specific pain system. Cardiac and blood pressure were also found to change, but these changes were not correlated to changes in nociception. Taken together, the data suggest that the acutely administered selective serotonin reuptake inhibitors may exacerbate an acute type of pain.  相似文献   

16.
洪刚  张庄  任立志 《冶金分析》2004,24(Z2):483-485
传统的摆锤试验机冲击吸收功的测量均采用刻度表盘方式,这种方法简单易行,但测量精度较差,在实际操作中经常出现误操作.本文提出-种利用计算机测量冲击吸收功的方法,可大大提高冲击吸收功的测量精度,并且实现试验机的全自动操作.  相似文献   

17.
Progress in micro or macro replantation has resulted in higher survival rates of formerly amputated parts. More amputated digits or limbs survive because the time of ischemia can be exceeded by using cold storage or perfusion. Homo or heterodigital vessel transposition, expanded indications for vein graft interposition, as well as heterotopic transplantation allow for extremity preservation even in crush injuries, and in disastrous multiple amputations combined with contusion or avulsion. Secondary reconstruction with regard to bone defects, tendon repair, and eventual nerve grafting have to be aspired, finally leading to an improvement of functional results in daily and leisure activities as well as in early professional readaptation. A total of 114 microvascular extremity replantations/revascularizations with a survival rate of 77.2% were followed for an average of 15 years.  相似文献   

18.
GOALS: To describe the interrelationships of douching, sex during menses, dry sex, and anal intercourse and their associations with self-reported history of sexually transmitted diseases (STD). STUDY DESIGN: The authors interviewed by telephone 422 white Americans (WA) and 44 African Americans (AA) selected using random-digit dialing, and 135 AA selected from a listed sample of census tracks having a population of at least 40% AA. RESULTS: After adjusting for lifetime numbers of vaginal sex partners, sex during menses was associated with self-reported history of chlamydial infection among women (WA: odds ratio [OR] = 3.9; confidence interval [CI]: 1.1, 14.0; AA: OR = 1.6; CI: 0.6, 4.2). Anal sex was associated with self-reported history of genital warts, genital herpes, hepatitis, and gonorrhea; douching with a twofold increase in self-reported pelvic inflammatory disease. Anal sex was most common in women with a history of same- and opposite-sex partners. CONCLUSIONS: These data confirm the association of douching and anal sex with various STD and suggest that sex during menses is associated with chlamydial infection.  相似文献   

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Aspirin caused epithelial hyperplasia, papillary necrosis with calcification and cortical changes in the rat kidney. After unilateral nephrectomy the lesions appeared more rapidly and were more severe. In the electron microscope the earliest changes were observed in the interstitial cells.  相似文献   

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