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21.
Sequence specificity of mutations induced by benzo[a]pyrene-7,8-diol-9,10-epoxide at endogenousaprt gene in CHO cells 总被引:11,自引:0,他引:11
We have determined the spectrum of mutations induced, by±trans-7,8-dihydroxy-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a] pyrene (BPDE) at the endogenous aprt locus in an hemizigous Chinese hamster ovary cell line exposed to 0.7 M BPDE. Southern analysis of 59 independent mutants revealed no major genomic alterations, indicating that gene inactivation was the result of a point mutation. This conclusion was confirmed by the cloning and sequencing of 21 of these mutants. The predominant mutation, the GCTTA transversion, comprised 62% of the spectrum, but other base pair substitutions and frameshifts were recovered. An examination of the target sequences for BPDE mutation revealed that mutations were localized within runs of GC base pairs. However, approximately half of these GC runs involved a particular sequence—a run of guanines flanked by adenine residues. Of seven such sites within the coding sequence ofaprt, mutations were clustered within five of them. This class of sequence occurs at codon 61 of the human C-Ha-ras1 protooncogene and may account for the selective activation of this codon by BPDE. 相似文献
22.
Dorota Skrzypczak Alicja Ewa Ratajczak Aleksandra Szymczak-Tomczak Agnieszka Dobrowolska Piotr Eder Iwona Krela-Ka
mierczak 《Nutrients》2021,13(2)
Sarcopenia is a disorder characterized by a loss of muscle mass which leads to the reduction of muscle strength and a decrease in the quality and quantity of muscle. It was previously thought that sarcopenia was specific to ageing. However, sarcopenia may affect patients suffering from chronic diseases throughout their entire lives. A decreased mass of muscle and bone is common among patients with inflammatory bowel disease (IBD). Since sarcopenia and osteoporosis are closely linked, they should be diagnosed as mutual consequences of IBD. Additionally, multidirectional treatment of sarcopenia and osteoporosis including nutrition, physical activity, and pharmacotherapy should include both disorders, referred to as osteosarcopenia. 相似文献
23.
ucja Zieliska-Tomczak Piotr Przymuszaa Szymon Tomczak Izabela Krzyko-Pieczka Ryszard Marciniak Magdalena Cerbin-Koczorowska 《Nutrients》2021,13(6)
The growing popularity of health education on social media indicates the need for its appropriate evaluation. This paper aims to present the potential of the Kirkpatrick Model (KM) with New World Kirkpatrick Model (NWKM) additions to evaluate the nutritional education provided by dieticians via Instagram. Instagram profiles of ten dieticians providing nutritional education for their followers were analyzed in March and April 2021. The study sample included profiles of both macro- and micro-influencers. The analyzed quantitative data included Instagram Engagement Rate and the number of likes and comments per post. The qualitative analysis of the comments was performed following the theoretical framework provided by the KM and NWKM. Collected data showed followers’ satisfaction, commitment, and relevance of the presented content, fulfilling the Level 1 of NWKM. Level 2 of NWKM was represented by 4 out of 5 dimensions (knowledge, attitude, confidence, commitment). No comments were found only for skills. Both Levels 3 (Behavior) and 4 (Results) of the KM were met. However, the use of the NWKM for them seems limited. The KM can be used to evaluate nutritional education on social media. The NWKM additions seem applicable mostly for Levels 1 and 2. 相似文献
24.
Piotr Sobolewski Monika Elbieta D
wigaa Maria Maliska Elbieta Szymaska Irena Walecka 《Reumatologia》2021,59(1):9
IntroductionA fast and cheap method of skin assessment in systemic sclerosis (SSc) is an area of extensive research. Established in 1979, the Rodnan skin score is a palpation-based method used among clinicians. This method has some limitations, such as: examiner’s skills, subjective results, and no standardization. In the last few years researchers have been exploring ultrasound-based techniques as a possible tool for skin assessment among patients with SSc. The aim of the study is to develop a protocol of elastography-based skin imaging evaluation among patients with SSc.Material and methodsReview of the literature and own experience.ResultsProposition of elastography-based skin imaging protocol among patients with SSc.ConclusionsThe authors present a potential protocol of ultrasound-based examination of skin involvement among patients with SSc. 相似文献
25.
26.
Richard Erskine Piotr K. Janicki Gail Neil Michael F. M. James 《Journal canadien d'anesthésie》1994,41(7):632-638
The purpose of this study was to compare neutrophil cidal activity during general or spinal anaesthesia. Assays were performed on neutrophils extracted from the blood of patients after surgery had been under way for one hour. First, the ability of the neutrophils to kill a standard laboratory strain of S. aureus was examined. Neutrophils extracted from the blood during surgery in the spinal anaesthetic group and incubated with the staphylococci for one hour killed twice as many bacteria than those from two groups of patients that received halothane or isoflurane general anaesthesia (P < 0.05). This effect persisted, to a lesser extent, in the spinal group neutrophils after two hours of incubation with the bacteria. Second, neutrophils from patients under the same conditions of surgery and anaesthesia were tested to examine the effect of the different anaesthetic techniques on neutrophil biocidal mechanisms. Neutrophils extracted during surgery in the spinal group released more superoxide in response to phorbol-12-myristate-13-acetate (PMA) than those from both groups of patients that received general anaesthesia (P < 0.05). It is concluded that there is an increased state of reactivity of the neutrophil cell membrane NADPH oxidase system in patients receiving spinal anaesthesia than in patients receiving general anaesthesia. 相似文献
27.
Antibiotic Administration in Patients Undergoing Common Surgical Procedures in a Community Teaching Hospital: The Chaos Continues 总被引:3,自引:0,他引:3
The influence of recently published guidelines by the Surgical Infection Society (SIS) on current surgical practice are not
well documented. The appropriateness of antibiotic administration in a cohort of surgical patients undergoing elective and
emergency surgery in a department of surgery in an urban, community-based, private, 560-bed teaching hospital was retrospectively
reviewed. The following were the criteria defining administration as appropriate as modified from SIS guidelines: Prophylactic
use: (1) started prior to operation; (2) spectrum appropriate to the specific operation; (3) duration ≤ 24 hours. Therapeutic
use: (1) started prior to operation; (2) spectrum appropriate to pathology; (3) Duration ≤ 24 hours for contamination or “resectable”
infection and ≤ 5 days for established infection in the absence of clinical evidence of persisting infection. Any switchover
from an appropriate agent to another appropriate or inappropriate agent in the same patient in the absence of microbiologic
or clinical indication was considered inappropriate administration. We reviewed the charts of 211 randomly selected patients
who underwent elective (n= 132) or emergency (n= 79) procedures during 1996. The operations included gastrectomy (n= 22), appendectomy (n= 27), open (n= 5) or laparoscopic (n= 27) cholecystectomy, colectomy (n= 28), hysterectomy (n= 8), laparotomy for intestinal obstruction (n= 11), mastectomy (n= 26), and ventral hernia repair (n= 37). A total of 17 antibiotics were used for prophylaxis and 21 for therapy. In 156 patients (74%) the administration was
considered inappropriate. Eight patients in the inappropriate group developed diarrhea (two cases of Clostridium difficile-induced colitis) compared to two cases of diarrhea in the appropriate group (nonsignificant). The average duration of administration
after elective and emergency operations was 3.3 and 5.7 days, respectively. The total expense for excessive duration of administration
was $18,533. Many surgeons are not familiar with the spectrum of antimicrobials and often do not distinguish between prophylactic
and therapeutic administration. Antibiotic usage in current surgical practice is often inappropriate, excessive, and chaotic. 相似文献
28.
It has been suggested that otoacoustic emissions, particularly transient-evoked otoacoustic emissions (TEOAE), might be more sensitive in assessment of changes to the cochlea caused by noise than pure-tone audiometry (PTA). The aim of the study was to compare temporary threshold shifts with the changes in TEOAE following a six-hour exposure to industrial noise at the intensity of 85-97 dB (A). Thirty two male employees of a metal factory were screened. TEOAE, PTA and tympanometry were included in the hearing test battery. Both, PTA and TEOAE showed significant reduction due to noise exposure, but no correlation between temporary threshold shifts and decreases in either the overall TOAE level or the level of otoacoustic emission in the frequency bands was found. Our results confirm the high sensitivity of TEOAE to short exposure to industrial noise. This study may recommend this measurement as a method of evaluation for TTS conditions for hearing conservation programme purposes, in addition to pure-tone audiometry. 相似文献
29.
Low doses of oxytocin facilitate social recognition in rats 总被引:7,自引:0,他引:7
Social recognition of juveniles by adult male residents has been shown to be modulated by neurohypophyseal hormones. The decrease of social investigation behavior during a second encounter with the same juvenile serves as index for social recognition. In the present study it was found that low doses (0.09–6.0 ng · kg–1) of oxytocin (OXT) given subcutaneously dose dependently facilitated social recognition. The effect of OXT appeared specific, since no change in social investigation was found when a novel juvenile was tested during the second encounter. No disturbances of social recognition by the low doses of OXT could be detected, in contrast to higher doses of this hormone. Other neurohypophyseal hormones, vasopressin and vasotocin, did not facilitate social recognition when tested in the same range of low doses. 相似文献
30.
Piotr Kruszewski Maria Luisa Fasano AIf O. Brubakk Jie Ming Shen Trond Sand Ottar Sjaastad 《Headache》1991,31(6):399-405
The recently described "Sunct" syndrome is a rare picture of unilateral, shortlasting headache attacks accompanied by autonomic phenomena (conjunctival injection, tearing, etc.) on the symptomatic side. Heart rate and blood pressure were monitored in two elderly "Sunct" patients during and outside headache attacks. An ultrasound Doppler servo method was used for the non-invasive, continuous, beat-to-beat determination of instantaneous arterial blood pressure. In a third patient, systolic and diastolic blood pressure, both outside and during pain paroxysms, were assessed using the standard Korotkoff method. Heart rate was found to be significantly decreased during pain paroxysms. Systolic blood pressure was observed to be significantly increased during attacks, when compared with the inter-attack period, while a less consistent pattern was observed for diastolic blood pressure. Some of the changes in the cardiovascular system seemed to start prior to pain onset. Therefore, it seems unlikely that these changes were caused by pain activation of the sympathetic nervous system or the oculocardiac reflex. 相似文献