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排序方式: 共有1219条查询结果,搜索用时 15 毫秒
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Razeq Shetab Stuart H. Cohen Thomas Prindiville Yajarayma J. Tang Mary Cantrell Darush Rahmani Joseph Silva Jr. 《Journal of clinical microbiology》1998,36(6):1729-1732
Bacteroides fragilis constitutes about 1% of the bacterial flora in intestines of normal humans. Enterotoxigenic strains of B. fragilis have been associated with diarrheal diseases in humans and animals. The enterotoxin produced by these isolates induces fluid changes in ligated intestinal loops and an in vitro cytotoxic response in HT-29 cells. We developed a nested PCR to detect the enterotoxin gene of B. fragilis in stool specimens. After DNA extraction, a 367-bp fragment was amplified with two outer primers. The amplicon from this reaction was subjected to a second round of amplification with a set of internal primers. With these inner primers, a 290-bp DNA fragment was obtained which was confirmed as part of the B. fragilis enterotoxin gene by Southern blotting with a nonradioactive internal probe and a chemiluminescence system. By this approach, B. fragilis enterotoxin gene sequences were detected in eight known enterotoxigenic human isolates and nine enterotoxigenic horse isolates. No amplification products were obtained from DNA extracted from 28 nonenterotoxigenic B. fragilis isolates or B. distasonis, B. thetaiotaomicron, B. uniformis, B. ovatus, Escherichia coli, or Clostridium difficile. The sensitivity of this assay allowed us to detect as little as 1 pg of enterotoxin DNA sequences or 100 to 1,000 cells of enterotoxigenic B. fragilis/g of stool. Enterotoxin production of all isolates was confirmed in vitro in HT-29 cells. A 100% correlation was obtained between enterotoxin detection by cytotoxin assay and the nested PCR assay. This rapid and sensitive assay can be used to identify enterotoxigenic B. fragilis and may be used clinically to determine the role of B. fragilis in diarrheal diseases. 相似文献
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Elizabeth S Hart Marilyn H Kelly Beth Brillante Clara C Chen Navid Ziran Janice S Lee Penelope Feuillan Arabella I Leet Harvey Kushner Pamela G Robey Michael T Collins 《Journal of bone and mineral research》2007,22(9):1468-1474
Most lesions in FD and their attendant functional disability occur within the first decade; 90% of lesions are present by 15 years, and the median age when assistive devices are needed is 7 years. These findings have implications for prognosis and determining the timing and type of therapy. INTRODUCTION: Fibrous dysplasia of bone (FD) is an uncommon skeletal disorder in which normal bone is replaced by abnormal fibro-osseous tissue. Variable amounts of skeletal involvement and disability occur. The age at which lesions are established, the pace at which the disease progresses, if (or when) the disease plateaus, and how these parameters relate to the onset of disability are unknown. To answer these questions, we performed a retrospective analysis of a group of subjects with FD. MATERIALS AND METHODS: One hundred nine subjects with a spectrum of FD were studied for up to 32 years. Disease progression was assessed in serial (99)Tc-MDP bone scans by determining the location and extent of FD lesions using a validated bone scan scoring tool. Physical function and the need for ambulatory aids were assessed. RESULTS: Ninety percent of the total body disease skeletal burden was established by age 15. Disease was established in a region-specific pattern; in the craniofacial region, 90% of the lesions were present by 3.4 yr, in the extremities, 90% were present by 13.7 yr, and in the axial skeleton, 90% were present by 15.5 yr. Twenty-five of 103 subjects eventually needed ambulatory aids. The median age at which assistance was needed was 7 yr (range, 1-43 yr). The median bone scan score for subjects needing assistance was 64.3 (range, 18.6-75) compared with 23.1 (range, 0.5-63.5) in the unassisted subjects (p < 0.0001). Among subjects needing assistance with ambulation, 92% showed this need by 17 yr. CONCLUSIONS: The majority of skeletal lesions and the associated functional disability occur within the first decade of life. The implication is that the window of time for preventative therapies is narrow. Likewise, therapeutic interventions must be tailored to where the patient is in the natural history of the disease (i.e., progressive disease [young] versus established disease [older subjects]). These findings have implications for prognosis, the timing and type of therapy, and the development of trials of new therapies and their interpretation. 相似文献
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n = 62, p < 0.05), emergent CEA (n= 2, p= 0.01), and need for postoperative anticoagulation (n= 2, p= 0.01). Only 56 (15%) of patients had indications for ICU admission, 57 (16%) would have been admitted to an EKG-monitored
nursing unit, and 252 (69%) would have been admitted to a standard nursing unit. Immediate admission to the ICU after CEA
is indicated for patients undergoing emergent CEA, those requiring anticoagulation postoperatively, those with intraoperative
stroke or major cardiac complication, and possibly those with chronic renal failure. All other patients should be admitted
to the RR. Patients experiencing stroke, major cardiac events, significant wound hemorrhage, or reintubation in the RR, and
those requiring vasoactive medication more than 3 hours after surgery should be transferred to the ICU. Patients with indications
of cardiac disease within 6 months prior to CEA but no indications for ICU admission may be discharged from the RR to an EKG
monitored unit. All others may be discharged to a standard nursing unit. 相似文献
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Hee Jeong Han Sina Labbaf Jessica L. Borelli Nikil Dutt Amir M. Rahmani 《Journal of medical engineering & technology》2020,44(4):177-189
AbstractMonitoring people’s stress levels has become an essential part of behavioural studies for physical and mental illnesses conducted within the biopsychosocial framework. There have been several stress assessment studies in laboratory-based controlled settings. However, the results of these studies do not always translate effectively to an everyday context. The current state of wearable sensor technology allows us to develop systems measuring the physiological signals reflecting stress 24/7 while capturing the context. In this paper, we present a stress monitoring system that provides objective daily stress measurements in everyday settings based on three physiological signals: electrocardiogram (ECG), photoplethysmogram (PPG), and galvanic skin response (GSR) using Shimmer3 ECG, Shimmer3 GSR+, and Empatica E4 wearable sensors. We perform controlled stress assessment experiments on 17 participants in which we successfully detect stress with a 94.55% accuracy for 10-fold cross-validation and an 85.71% accuracy for subject-wise cross-validation. In everyday settings, the system assesses stress with an 81.82% accuracy. We also examine whether motion artefacts affect stress assessment and filter the low-confidence readings to minimise false alarms. 相似文献
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The kidneys are vital organs in the management of fluid balance, waste product removal, electrolyte homeostasis, acid–base balance and endocrine function. Waste products removed by the kidney are urea, uric acid and creatinine; other foreign products with similar physiochemical properties are also excreted. Urea and uric acid are by products of protein metabolism and creatinine is generated by the metabolism of creatine compounds from muscle. The kidney regulates fluid and electrolyte balance through controlling the composition and volume of urine. In the proximal convoluted tubule and the loop of Henle, 90% of sodium, potassium, calcium and magnesium are reabsorbed. Acid–base balance is achieved by regulating the excretion of hydrogen ions and bicarbonate buffering. The kidney also has a number of endocrine functions including the production of renin and erythropoietin as well as hydroxylation of vitamin D. The kidneys receive 25% of cardiac output, generating 170–200 litres of ultrafiltrate per day. Urine output is approximately 1.5 litres per day, which is concentrated ultrafiltrate through selective reabsorption of solutes and water. In this article we will discuss tests frequently used to assess renal function. 相似文献
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Yosuf EL-Shabrawi Navid Ardjomand Cristoph Faschinger Gerald H?fler 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1999,164(1):405-407
Background: Lattice dystrophy is an autosomal-dominantly inherited disease. A mutation of the gene coding for kerato-epitheline has been found in patients with this stromal dystrophy. In codon 124 a Guanine to Adenine mutation of the nucleotide 417 has been described. We looked for this mutation in a family with lattice dystrophy treated in our clinic. 相似文献