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PUVA is used to treat severe skin problems that have not responded well to more conventional forms of treatment. The effectiveness of PUVA therapy depends on patient compliance and careful administration and evaluation of patient response to treatment. The following protocol was developed to identify important factors to consider when administering PUVA therapy.  相似文献   

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Segmental colonic transit has been measured in 101 patients. Two MBq of 111Indium absorbed on resin pellets and encapsulated in an enteric coated capsule was given at 7 00 am. Hourly images during the first day, and three images during each subsequent day were acquired for up to three days. Using all scan and patient data the scans were categorised in one of the five patterns of colonic transit: normal, rapid, right delay, left delay, or generalised delay. The geometric centres and per cent activity at each time point was compared between the five groups of colonic transit patients to find the best time for imaging and so to distinguish the five groups. During the first day, early images did not help in diagnosis of patterns of transit, however, in the later images (six hours onwards after the ingestion of the activity) the rapid transit groups could be identified. Images at 27 and 51 hours were both required to distinguish all five groups of patients from each other. Only in the 'normal' transit patients was there some excretion of the activity during the course of the second day, otherwise there was no difference in the images taken in the course of a day (second or third day). A simplified protocol requires a minimum of three images to distinguish all five patterns of colonic transit. The activity should be ingested in the morning (7 00 am) and the first image taken at the end of the working day (8-10 hours after ingestion), the second image on the morning of the second day, and the third image during the course of the third day. This simple protocol would provide all the clinically relevant information necessary for correct classification of the colonic transit.  相似文献   

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TRAP (trp RNA-binding attenuation protein) regulates expression of the tryptophan biosynthetic genes in response to tryptophan in Bacillus subtilis by binding to two sites containing a series of 9 or 11 (G/U)AG triplet repeats that are generally separated by two or three spacer nucleotides. Previous mutagenesis experiments have identified three TRAP residues, Lys-37, Lys-56, and Arg-58 that are essential for RNA binding. The location of these residues on the TRAP oligomer supports the proposal that RNA binds TRAP by encircling the TRAP oligomer. In this work, we show that RNAs containing 11 GAG or UAG repeats separated by CC dinucleotide spacers (((G/U)AGCC)11) form stable structures that inhibit binding to TRAP. This conclusion is based on the effects of temperature and Mg2+ on the affinity of TRAP for RNAs with CC spacers combined with UV hyperchromicity and circular dichroism. Furthermore, introducing the base analogue 7-deazaguanosine in the ((G/U)AGCC)11 RNAs stabilized the TRAP-RNA interaction. This effect was associated with decreased stability of the RNA structure as measured by circular dichroism spectroscopy. The precise nature of the structure of the ((G/U)AGCC)11 RNAs is not known but evidence is presented that it involves noncanonical interactions. We also observed that substitution of Arg-58 with Lys further reduced the ability of TRAP to interact with structured RNAs. Since in vivo function of TRAP may involve binding to structured RNAs, we suggest a potential function for this residue, which is conserved in TRAP from three different bacilli.  相似文献   

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Although three-dimensional (3-D) treatment planning has primarily been used for external beam radiation therapy, the advantages of 3-D treatment planning can be realized for brachytherapy applications. As with teletherapy, the use of 3-D treatment planning for brachytherapy can provide both superior dose distribution as well as detailed evaluations of the relationship of dose and volume in critical structures and target tissues. Conventional 3-D treatment planning uses computed tomography (CT) scans to localize structures; however, localizing individual brachytherapy sources on each CT slice can be impractical for routine clinical use. In the transition from two-dimensional to 3-D localization and dose evaluation of interstitial perineal templates in particular, a practical method of seed localization on a postimplant CT dataset has been developed. This method does not utilize dummy sources and, as such, does not require individual seed locations to be identified. Instead, the position of the afterloading catheter is defined as a reference line by connecting its location as seen on the axial CT slices and seed locations defined along its length. Full volumetric calculations can then be performed, including dose-volume histograms (DVH) for critical organs and tumor volumes. Source localization and normal tissue doses were calculated using both orthogonal films and the 3-D method for a series of perineal template guided implants. Point dose calculations of the rectum and bladder were obtained from orthogonal films and were then compared to the corresponding DVHs for these organs.  相似文献   

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The simple syringe-stabilizer unit described in this note provides a means for rapid intravascular inoculation of embryonated chicken eggs with minimal embryonic death from vascular trauma.  相似文献   

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宋波  李悦 《工程科学学报》2011,33(4):509-514
基于Morison动水理论,提出了作用于高桩承台的动水力简便计算方法,该方法可以应用于深水大跨度桥梁抗震设计.以南京长江三桥南塔基础为原型,利用水中振动台试验,通过对比无水和有水状态时动力荷载作用下的模型试验和计算的结果,验证了动水力简便计算方法的准确性和可靠性,并对影响动水力的主要影响因素进行了重点讨论.  相似文献   

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Recently, a new method for measuring telomere lengths based on telomere DNA content was developed. The method, which is based on the ratio of telomere to centromere DNA content (TC ratio), is highly sensitive, allowing the analysis of small quantities of DNA. However, the method required the isolation of DNA, which can be difficult or impossible for small numbers of cells. Here, we suggest an improvement of this method that can directly estimate telomere lengths from whole cells. We optimized the method for whole cells and purified DNA and found that accurate TC ratios can be obtained from as little as 9 ng of DNA or 800 whole cells. There was no statistically significant difference between the ratios obtained with purified DNA or with whole cells, indicating that the isolation of DNA is not necessary for small samples.  相似文献   

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BACKGROUND: Amplification methods identify Microbacterium tuberculosis on the basis of genus- or species-specific sequence of bases in nucleic acids which they replete exponentially. The objective of the work was comparison of results of biological samples by the method Gen-Probe Mycobacterium tuberculosis Direct Test (MTD) using amplification of ribosomal RNA and BK by microscopy and cultivation, assessment of standard indicators of their efficiency of the method and analysis of diverging results. METHODS AND RESULTS: During the period between April 19, 1994 and October 19, 1995 a total of 650 specimens from 316 patients examined for suspected tuberculosis were processed. After decontamination the specimens were divided into two portions and examined by the Gen-Probe MTD and by classical BK microscopy and cultivation. 95 specimens were Gen-Probe MTD positive. As compared with BK cultivation the sensitivity of Gen-Probe MTD is 94.7%, the specificity 93.1%, the positive predictive value 56.8% and the negative predictive value 99.5%. Falsely positive were the specimens from 33 patients, most frequently with a diagnosis of tumours, non-specific bronchopneumonias and interstitial pulmonary fibroses. CONCLUSIONS: Gen-Probe MTD is a rapid examination with an equal or higher sensitivity than BK cultivation. The disadvantage is a somewhat lower specificity and higher cost.  相似文献   

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丁杰 《包钢科技》2005,31(4):89-91
主要介绍现浇混凝土受弯构件造成承载力不足的原因,对混凝土受弯构件进行加固补强的理论基础,以及加固补强方法--体外配筋补强法的计算依据和注意事项.  相似文献   

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This paper gives an overview of a lecture scheduled for the opening of the 10th European Bioenergetics Congress. In this lecture I plan to first reflect on the accomplishments of some of the individuals who were involved in research on the ATP synthase during the past 50 years. Then I will give a brief view of the present information about rotational catalysis by the ATP synthase. This will be followed by a discussion of some results from my laboratory that call for additional experimentation. Finally I will direct attention to other questions about the ATP synthase that should be addressed in future studies.  相似文献   

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BACKGROUND: The role of chest CT scan in the assessment of patients with hemoptysis is uncertain. AIM: To evaluate the usefulness of CT scan in patients with non massive hemoptysis. PATIENTS AND METHODS: Ninety six patients, 60 male, aged 23 to 76 years old, who presented with hemoptysis to an University Hospital, were studied. All patients were studied with a chest radiograph, a fiberoptic bronchoscopy and a high resolution CT scan. RESULTS: The final causes of hemoptysis were bronchiectasis in 27 cases, bronchogenic carcinoma in 24 cases and lung infections in nine. The source of bleeding was not identified in 18 patients (19%). CT scan clarified abnormalities seen in the chest radiograph in 30 patients (31%) and provided new diagnostic information in 13 (14%). CT scan correctly localized the source of bleeding found by fiberoptic bronchoscopy in 35 of 43 patients (81%), whereas chest radiograph did so in 27 (77%). All patients with bronchogenic carcinoma were identified by chest radiograph or bronchoscopy. Twenty of the 27 patients with bronchiectasis had radiological abnormalities in the chest radiograph. In only two patients, with lung metastases and non conclusive chest radiograph and bronchoscopy, CT scan provided information that significantly modified clinical management. CONCLUSIONS: CT scan was useful to stage patients with bronchogenic carcinoma and to assess the extension of bronchiectasis, but its impact in the management and clinical evolution of patients was limited. Therefore we do not recommend the routine use of CT scan in the assessment of patients with hemoptysis.  相似文献   

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Software has been developed for potential energy surface analysis and the local minima method of pharmacophore determination. LMM is rigorous and systematic and employs multiple conformations which are the local minima from the potential energy surface of each compound in the data set. It produces a series of possible pharmacophores from a postulated set of pharmacophore elements. The best pharmacophore is then determined by performing a comparative molecular field analysis (CoMFA) on each one. The pharmacophore which produces the most self-consistent model is deemed the best. Local minima on the gas-phase potential energy surface are shown to be a reasonably close approximation to protein bound conformations, and these conformations can be found through systematic conformational searches followed by minimization of the local minima. LMM was used to develop a 3D-QSAR model for dopamine beta-hydroxylase (DBH) inhibitors which was highly predictive (predictive R2 = 0.71 and standard error of predictions = 0.41). The model predicted that the phenyl and thienyl series of inhibitors were acting as bioisosteres. Examination of compounds overlayed in the model indicated a possible hydrogen bond acceptor in the DBH active site. Three tyrosine residues previously labeled by mechanism based inhibitors may be acting as the acceptor and therefore represent excellent candidates for site-directed mutagenesis studies.  相似文献   

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