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41.
Trifluoroethanol (TFE) is often used to increase the helicity of peptides to make them usable as models of helices in proteins. We have measured helix propensities for all 20 amino acids in water and two concentrations of trifluoroethanol, 15 and 40% (v/v) using, as a model system, a peptide derived from the sequence of the alpha-helix of ribonuclease T1. There are three main conclusions from our studies. (1) TFE alters electrostatic interactions in the ribonuclease T1 helical peptide such that the dependence of the helical content on pH is lost in 40% TFE. (2) Helix propensities measured in 15% TFE correlate well with propensities measured in water, however, the correlation with propensities measured in 40% TFE is significantly worse. (3) Propensities measured in alanine-based peptides and the ribonuclease T1 peptide in TFE show very poor agreement, revealing that TFE greatly increases the effect of sequence context. 相似文献
42.
43.
VM Ponomarenko 《Canadian Metallurgical Quarterly》1995,(5-6):12-15
An assessment is submitted of morbidity rates and physical development of children aged under 14, residing in the territories being monitored after the Chernobyl Power Plant accident. A high level of disharmony in physical development of the children examined was recordable, as was an excess in morbidity of both general and separate classes of disease entities among the pediatric population having been victims of the Chernobyl accident, as compared to that in relatively "clean" areas and in Ukraine as a whole. 相似文献
44.
Helicase II (uvrD gene product) and helicase IV (helD gene product) have been shown previously to be involved in the RecF pathway of recombination. To better understand the role of these two proteins in homologous recombination in the RecF pathway [recBCsbcB(C) background, we investigated the interactions between helD, uvrD and the following RecF pathway genes: recF, recO, recN and ruvAB. We observed synergistic interactions between uvrD ant the recF, recN, recO and recG genes in both conjugational recombination and the repair of methylmethane sulfonate (MMS)-induced DNA damage. No synergistic interactions were detected between helD and the recF, recO and regN genes when conjugational recombination was analyzed. We did, however, detect synergistic interactions between helD and recF/recO in recombinational repair. Surprisingly, the uvrD deletion completely suppressed the phenotype of a ruvB mutation in a recBCsbcB(C) background. Both conjugational recombination efficiency and MMS-damaged DNA repair proficiency returned to wild-type levels in the deltauvrDruvB9 double mutant. Suppression of the effects of the ruvB mutation by a uvrD deletion was dependent on the recG and recN genes and not dependent on the recF/O/R genes. These data are discussed in the context of two "RecF" homologous recombination pathways operating in a recBCsbcB(C) strain background. 相似文献
45.
Pulmonary diseases caused by dust occupy a leading place in occupational morbidity structure. Those diseases inspire much attention due to their high prevalence, especially in ecologically hazardous regions where the workers are under "double exposure". Upper respiratory tract diseases serve as a trigger for all respiratory disorders in workers exposed to dust. Early diagnosis of respiratory disorders includes history, clinical data, X-ray examination and assessment of pulmonary ventilation and together with concurrent cardiovascular diagnosis is necessary for well-justified prophylaxis. 相似文献
46.
When initiating monotherapy for the treatment of essential hypertension, multiple determinants factor into the decision. The goal of treatment is to lower blood pressure and lessen the likelihood of progression to target organ failure. Physicians frequently prioritize these determinants and make decisions to initiate monotherapy based on the race of an individual. All too often, however, the black/white issue is overstated and given too much consideration. The overall goal of this review is to suggest the appropriate "role" for racial profiling in the initial selection of an antihypertensive agent. 相似文献
47.
VM Grace 《Canadian Metallurgical Quarterly》1998,28(1):127-151
Chronic pelvic pain in the absence of organic pathology identifiable in medical terms is considered one of the most perplexing conditions that gynecologists confront. A critical analysis of the medical, psychiatric, and psychological literature on chronic pelvic pain without organic pathology reveals that the dichotomous construct of mind and body underpinning medical research and understanding is a barrier to the successful diagnosis and treatment of this condition, and indeed to the productive engagement of the health professional with the patient. The strict duality of the condition's etiology being understood in either physiological or psychogenic terms has been questioned at times over the last 40 years, but only recently has an "integrative model" been proposed. However, it is argued here that although the development of a multidisciplinary approach is important, only a radical deconstruction of the medical paradigm will truly address the problem and enable a real change in practice. 相似文献
48.
The aim of the study was TPS diagnostic value determination in the serum of women with breast cancer as compared with MCA and CA 15-3. The relationship between the serum concentration of these antigens and patient age, clinical stage, histological grade, presence of metastases to lymph nodes and histological type of neoplasm was evaluated. Studies were conducted on the sera of 139 women before surgical procedure aged 28-81, treated in the Clinic of Oncology, at Karol Marcinkowski University of Medical Sciences in Poznań. The TPS concentration was determined using the "BEKI Diagnostics" immunoenzymatic method, MCA - by the "Roche" test and CA 15-3 concentration was determined by the "Abbott" immunofluorescent test. The study showed significantly higher levels of TPS, CA 15-3 and MCA in women with cancer, compared with values in healthy women and women with mastopathy. The highest median of concentration and frequency of occurrence was obtained for TPS. A correlation between enhancement of TPS and CA 15-3 concentration with clinical stage was observed. A similar connection was noted in women with metastases to the lymph nodes. Serum MCA concentration results did not demonstrate the above effects. The study suggests, that in estimating the clinical condition of women with breast cancer, the simultaneous determination of TPS with CA 15-3 seems to be a more useful prognostic factor than TPS or CA 15-3 with MCA. 相似文献
49.
Personal clinical observations during the recent years allow the authors to confirm the indisputable value of surgical experience got during the Great Patriotic War (1941-1945) and in particular, the "fourfold" scheme proposed by V. I. Voiachek for the diagnosis and treatment of blind gunshot wounds to the skull base. Computed tomography considerably increases the probability of detection of the exact localization of foreign bodies in complex anatomical structures of the skull and thus facilitates choosing the most rational surgical management. The use of the electro-optical transducer for the extraction of foreign bodies from almost inaccessible areas of the skull base decreases the risk of operation. 相似文献
50.
During a six-month period 2,221 haemocultures obtained from patients hospitalized in the Faculty Hospital Olomouc were examined. In all 304 isolated bacteria the sensitivity was assessed by the standard dilution micromethod and moreover all positive haemocultures were examined the "direct" disc method. Agreement between the results of the two methods was proved in 84% of pairs of tests and within a range from 67 to 100%, depending on the type of antimicrobial preparation. Based on these findings it may be stated that assessment of the sensitivity by the "direct" method agrees significantly with assessment of the sensitivity according to minimal inhibitory concentrations (MIC). In patients with septicaemia this procedure makes it possible to change empirical antibiotherapy by 24 hours sooner to aimed therapy. 相似文献