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21.
Aim—To compare the techniques and results of a nested PCR and an immunofluorescence assay (IFA) for the detection of Pneumocystis carinii infection; to consider the role of the nested PCR in the diagnosis of P carinii pneumonia (PCP).  相似文献   
22.
Pulmonary infection with mucoid strains of Pseudomonas aeruginosa in present in the majority of cystic fibrosis patients with chronic lung disease. It has been postulated that this mucoid coating may act to decrease lung clearance of Pseudomonas by limiting access of phagocytes, antibodies, and antibiotics to the bacteria. To determine whether mucoid coating of Pseudomonas might decrease intrapulmonary killing, groups of guinea pigs were infected with intrabronchial instillations of equivalent numbers of mucoid and nonmucoid Pseudomonas. For this study, mucoid strains of Pseudomonas were obtained from cystic fibrosis sputa and passaged on blood agar plates to obtain their nonmucoid revertants. Animals were then sacrificed at timed intervals after infection, and quantitative cultures were performed on lung homogenates. In all cases, mucoid challenge strains retained their mucoid morphology after passage in guinea pig lungs. No difference in killing of mucoid and nonmucoid Pseudomonas could be detected at 6, 24, or 48 h after lung infection. Further challenge studies used guinea pigs that were either prevaccinated with lipopolysaccharide P. aeruginosa vaccine or else treated with tobramycin sulfate after infection. Nonvaccinated or untreated controls had reduced intrapulmonary killing of Pseudomonas compared with vaccinees or treated groups (P < 0.02 and P < 0.01, respectively). However, there were no differences in pulmonary killing of mucoid and nonmucoid Pseudomonas in the presence of either specific antibodies or antibiotic. We conclude from these studies that mucoid coating of Pseudomonas does not selectively impede mechanisms of intrapulmonary killing in guinea pig lungs.  相似文献   
23.
Variations in the anatomy of the abdominal aorta and its branches are of interest as vessel geometry not only determines flow dynamics, but is also crucial in the pathogenesis of vascular disease. The relationship between the anterior visceral and renal arteries is important when undertaking diagnostic arteriography and endovascular interventions. To examine these relationships, the length of the abdominal aorta was determined and measurements taken of the position of origin of the celiac artery, superior mesenteric artery (SMA), inferior mesenteric artery (IMA) and renal arteries, as well as the three-dimensional projection of each vessel from the aorta. The mean level of bifurcation of the aorta was at the lower third of the body of L4, with the celiac artery, SMA, renal arteries and IMA arising at the level of the T12/L1 intervertebral disc, upper third of the body of L1, lower third of the body of L1 and lower third of the body of L3, respectively. The horizontal projection of the celiac artery, SMA and IMA was to the left of the midline; in the sagittal plane, the celiac artery and SMA projected anteriorly and the IMA posteriorly; in the coronal plane all vessels projected inferiorly, with the SMA to the right and the IMA to the left. The celiac artery, SMA and both renal arteries all arise from the proximal half of the abdominal aorta within 45 mm of each other, with the origins of the renal arteries being remarkably consistent. It is concluded that the celiac artery and SMA are both useful landmarks for determining the position of the renal arteries.  相似文献   
24.
Bradykinesia is one of the primary symptoms of Parkinson disease and leads to significant functional limitations for patients. Single joint movement studies, that have investigated the mechanism of bradykinesia, suggest that several features of muscle activity are disrupted, including modulation of burst amplitude and duration, and the number of bursts. It has been proposed that it is the blending of these different burst deficits that collectively defines bradykinesia. This study adds two new approaches to the study of bradykinesia. First, we examined the features of shoulder muscle activities during multijoint arm movement in bradykinetic and control subjects, such that previously reported single joint hypotheses could be tested for generalized arm movement. Second, we directly manipulated speed while keeping distance constant for a large range of speeds. In this manner, we could compare individual trials of muscle activity between controls and subjects with Parkinsons disease (PD) for movements matched for both speed and movement duration. Our results showed that while a multiple burst pattern of shoulder muscles was a common strategy for all subjects (young, elderly controls and PD), subjects with PD showed several burst abnormalities, including deficits in initial agonist burst amplitude and duration at both fast and slow speeds. Subjects with PD also (1) failed to produce a one-burst pattern at fast speeds and, instead, produced a predominance of multiple burst patterns and (2) showed a relationship between the number of burst deficits and the severity of disease. These results extend the findings of single joint studies to multi-joint and similarly indicate that a combination of burst modulation abnormalities correlate with bradykinesia and disease severity.  相似文献   
25.
An international advisory group met at the National Institutes of Health in Bethesda, Maryland in 2017, to discuss a new classification system for the ectodermal dysplasias (EDs) that would integrate both clinical and molecular information. We propose the following, a working definition of the EDs building on previous classification systems and incorporating current approaches to diagnosis: EDs are genetic conditions affecting the development and/or homeostasis of two or more ectodermal derivatives, including hair, teeth, nails, and certain glands. Genetic variations in genes known to be associated with EDs that affect only one derivative of the ectoderm (attenuated phenotype) will be grouped as non‐syndromic traits of the causative gene (e.g., non‐syndromic hypodontia or missing teeth associated with pathogenic variants of EDA “ectodysplasin”). Information for categorization and cataloging includes the phenotypic features, Online Mendelian Inheritance in Man number, mode of inheritance, genetic alteration, major developmental pathways involved (e.g., EDA, WNT “wingless‐type,” TP63 “tumor protein p63”) or the components of complex molecular structures (e.g., connexins, keratins, cadherins).  相似文献   
26.
The Micro-ID, a new identification kit for Enterobacteriaceae, consists of 15 biochemical tests, with substrates and reagents impregnated in filter paper disks. A 0.2-ml amount of an organism suspension equal to a 0.5 McFarland standard is pipetted into each of the compartments. After 4 h of incubation and addition of potassium-hydroxide (KOH) to the Voges-Proskauer test, the color reactions are read according to the recommendations of the manufacturer. A five-digit octal code number is derived from each set of reactions from which an identification is derived by using a code book. In a single-blind, comparative study of the Micro-ID system with the API 20E system (Analytab Products Inc.) and conventional biochemical tube media, we found that the Micro-ID and the API 20E systems gave a 90% identification correlation when each was compared with the conventional tube media. A comparison of all three systems gave an 82% overall identification correlation. When the common tests of Micro-ID and API 20E were compared with conventional tube media, we found that the tests in the Micro-ID performed as well as or better than those of the API 20E. Certain groups of organisms, i.e., Citrobacter, Enterobacter, Proteus, Salmonella, and Serratia genera, were found to give low correlation on certain common tests. When using primary isolation MacConkey plates from the clinical laboratory, only 74% of the plates with Enterobacteriaceae had sufficient numbers of colonies of each enteric organism to produce the 0.5 McFarland inoculum density required. Problems concerning the misidentification of some organisms are discussed.  相似文献   
27.
Poor diet is a leading cause of death in the United Kingdom (UK) and around the world. Methods to collect quality dietary information at scale for population research are time consuming, expensive and biased. Novel data sources offer potential to overcome these challenges and better understand population dietary patterns. In this research we will use 12 months of supermarket sales transaction data, from 2016, for primary shoppers residing in the Yorkshire and Humber region of the UK (n = 299,260), to identify dietary patterns and profile these according to their nutrient composition and the sociodemographic characteristics of the consumer purchasing with these patterns. Results identified seven dietary purchase patterns that we named: Fruity; Meat alternatives; Carnivores; Hydrators; Afternoon tea; Beer and wine lovers; and Sweet tooth. On average the daily energy intake of loyalty card holders -who may buy as an individual or for a household- is less than the adult reference intake, but this varies according to dietary purchase pattern. In general loyalty card holders meet the recommended salt intake, do not purchase enough carbohydrates, and purchase too much fat and protein, but not enough fibre. The dietary purchase pattern containing the highest amount of fibre (as an indicator of healthiness) is bought by the least deprived customers and the pattern with lowest fibre by the most deprived. In conclusion, supermarket sales data offer significant potential for understanding population dietary patterns.  相似文献   
28.
We developed an assay that detects minus-strand RNA as a surrogate for actively replicating severe acute respiratory syndrome coronavirus 2. We detected minus-strand RNA in 41 persons with coronavirus disease up to 30 days after symptom onset. This assay might inform clinical decision-making about patient infectiousness.  相似文献   
29.
BACKGROUND CONTEXTSurgery for vertebral column tumors is commonly associated with intraoperative blood loss (IOBL) exceeding 2 liters and the need for transfusion of allogeneic blood products. Transfusion of allogeneic blood, while necessary, is not benign, and has been associated with increased rates of wound complication, venous thromboembolism, delirium, and death.PURPOSETo develop a prediction tool capable of predicting IOBL and risk of requiring allogeneic transfusion in patients undergoing surgery for vertebral column tumors.STUDY DESIGN/SETTINGRetrospective, single-center study.PATIENT SAMPLEConsecutive series of 274 patients undergoing 350 unique operations for primary or metastatic spinal column tumors over a 46-month period at a comprehensive cancer centerOUTCOME MEASURESIOBL (in mL), use of intraoperative blood products, and intraoperative blood products transfused.METHODSWe identified IOBL and transfusions, along with demographic data, preoperative laboratory data, and surgical procedures performed. Independent predictors of IOBL and transfusion risk were identified using multivariable regression.RESULTSMean age at surgery was 57.0±13.6 years, 53.1% were male, and 67.1% were treated for metastatic lesions. Independent predictors of IOBL included en bloc resection (p<.001), surgical invasiveness (β=25.43 per point; p<0.001), and preoperative albumin (β=?244.86 per g/dL; p=0.011). Predictors of transfusion risk included preoperative hematocrit (odds ratio [OR]=0.88 per %; 95% confidence interval [CI, 0.84, 0.93]; p<0.001), preoperative MCHgb (OR=0.88 per pg; 95% CI [0.78, 1.00]; p=0.048), preoperative red cell distribution width (OR=1.32 per %; 95% CI [1.13, 1.55]; p<0.001), en bloc resection (OR=3.17; 95%CI [1.33, 7.54]; p=0.009), and surgical invasiveness (OR=1.08 per point; [1.06; 1.11]; p<0.001). The transfusion model showed a good fit of the data with an optimism-corrected area under the curve of 0.819. A freely available, web-based calculator was developed for the transfusion risk model (https://jhuspine3.shinyapps.io/TRUST/).CONCLUSIONSHere we present the first clinical calculator for intraoperative blood loss and transfusion risk in patients being treated for primary or metastatic vertebral column tumors. Surgical invasiveness and preoperative microcytic anemia most strongly predict transfusion risk. The resultant calculators may prove clinically useful for surgeons counseling patients about their individual risk of requiring allogeneic transfusion.  相似文献   
30.
A case is described in which bis (1, 1 dioxoperhydro-1, 2, 4-thiadiazinyl-4-) methane (Taurolin) has saferly been administered on a long term basis to prevent recurrent sepsis in a patient receiving parenteral nutrition. A 26-year-old male with Crohn's disease receiving parenteral nutrition suffered repeated episodes of sepsis and developed an infected intra-atrial thrombus despite repeated courses of antimicrobial chemotherapy and surgical intervention. Continued parenteral nutrition was essential du5e to intestinal failure. Taurolin was administered in the parenteral feed, as a 0.3% solution, to prevent recrudescent and recurrent infection. This concentration was shown, in vitro, to be bactericidal to a variety of pathogenic organisms. No recurrence of sepsis, nor any evidence of side effects was observed throughout the 12 month period of Taurolin administration. After 12 months the taurolin was discontinued and within 2 weeks the patient was re-admitted with recurrent septicaemia. Following re-introduction of Taurolin the infection was controlled and the patient remains well. In our experience the addition of taurolin to the nutritive feeds of a patient at risk of sepsis is a safe and effective method of preventing recurrent sepsis.  相似文献   
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