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951.
Patients with pulmonary atresia and intact ventricular septum have a poor prognosis with or without conventional surgical treatment. The best results of surgical treatment are obtained in those cases with a mild underdeveloped right ventricle and minor sinusoidal communication in the absence of important dysfunction of the tricuspid valve. We present five cases of pulmonary atresia with intact ventricular septum associated with dysfunction of the tricuspid valve. On the basis of radiographic, electrocardiographic and hemodynamic findings, this group of patients could not be distinguished from others without dysplasia of the tricuspid valve. Echocardiographic and angiocardiographic studies are mandatory in the differential diagnosis. A combination of systemic-pulmonary artery anastomosis associated with pulmonary valvotomy, when possible, and reconstruction of the right ventricular outflow tract are indicated for surgical solution of these malformations. However, tricuspid valve replacement is indicated in some cases.  相似文献   
952.
BACKGROUND: Idiopathic pulmonary arterial hypertension (iPAH) is a rare disease of unknown aetiology characterized by a poor prognosis. Impairment of nitric oxide (NO) synthesis or NO-induced vasorelaxation has been suspected to play a role in the development of iPAH. This study was performed to investigate possible correlations between the plasma levels of the NO-related aminoacids L-arginine, L-citrulline and N-hydroxy-L-arginine (L-NHA) and the severity of iPAH. METHODS: In twelve iPAH patients hemodynamics were measured by right heart catheterization, and plasma levels of L-arginine, L-citrulline and L-NHA were determined in blood samples from the pulmonary artery, peripheral artery and peripheral vein by high-performance liquid chromatography analysis. In eight of twelve patients a six minute walk test was performed. RESULTS: Plasma levels of L-arginine strongly correlated to right atrial pressure, cardiac output, cardiac index, mixed-venous oxygen saturation, six minute walk data and NYHA functional class at all sites of blood sampling (p < 0.05). CONCLUSIONS: The results suggest a possible role of the NO precursor L-arginine in the pathogenesis of iPAH.  相似文献   
953.
The development of antimicrobial resistance by bacteria has had profound effects on the clinical use of antibiotics, especially in hospital-acquired infections. In 1973, a large outbreak of nosocomial infections due to Serratia marcescens began at the Vanderbilt University medical complex, a major characteristic of which was high-level resistance to gentamicin and carbenicillin. Investigation of the outbreak and subsequent in vitro studies have shown that the evolution and epidemiology of this high-level resistance operated at three levels of organizations: (1)dissemination of individual strains, (2) dissemination of a plasmid among different strains and (3) movement of a discrete genetic element, or transposon, between plasmids. The investigations of this outbreak and other studies reviewed support the concept that resistant strains can evoke as a result of R-plasmid exchange within the hospital environment, providing an opportunity for control of this exchange can be interrupted.  相似文献   
954.
ObjectivesTo assess the attitudes, knowledge, and experiences of Brazilian resident physicians regarding religiosity/spirituality (R/S), factors associated with addressing this issue, and its influence on clinical practice.MethodsWe report results of the multicenter “Spirituality in Brazilian Medical Residents” (SBRAMER) study involving 7 Brazilian university centers. The Network for Research Spirituality and Health (NERSH) scale (collecting sociodemographic data, opinions about the R/S-health interface, and respondents’ R/S characteristics) and the Duke Religion Index were self-administered. Logistic regression models were constructed to determine those factors associated with residents’ opinions on spirituality in clinical practice.ResultsThe sample comprised 879 resident physicians (53.5% of total) from all years of residency with 71.6% from clinical specialties. In general, the residents considered themselves spiritual and religious, despite not regularly attending religious services. Most participants believed R/S had an important influence on patient health (75.2%) and that it was appropriate to discuss these beliefs in clinical encounters with patients (77.1%), although this was not done in routine clinical practice (14.4%). The main barriers to discussing R/S were maintaining professional neutrality (31.4%), concern about offending patients (29.1%), and insufficient time (26.2%). Factors including female gender, clinical specialty (e.g., internal medicine, family medicine, psychiatry) as opposed to surgical specialty (e.g., surgery, obstetrics/gynecology, orthopedics), having had formal training on R/S, and higher levels of R/S were associated with greater discussion of and more positive opinions about R/S.ConclusionBrazilian resident physicians held that religious and spiritual beliefs can influence health, and deemed it appropriate for physicians to discuss this issue. However, lack of training was one of the main obstacles to addressing R/S issues in clinical practice. Educators should draw on these data to conduct interventions and produce content on the subject in residency programs.Electronic supplementary materialThe online version of this article (10.1007/s11606-020-06145-x) contains supplementary material, which is available to authorized users.KEY WORDS: spirituality, religion and medicine, resident physicians, medical education, graduate students, medical residents  相似文献   
955.
The oestrogen receptor (ER) status of 2660 patients with primary breast cancer has been related to the effect of different adjuvant systemic therapies on survival. However, as patients in the various treatment groups also had different prognostic features comparison between treatments was difficult. Over 90% of patients receiving tamoxifen (Tam) were postmenopausal compared with <20% of those receiving chemotherapy (CT). The latter had more positive nodes (85% vs 54%) and grade III tumours (54% vs 30%) than the Tam group. The combined CT and Tam group had similar characteristics to the CT alone group. The current reported increase in the proportion of women with ER+ tumours is explained by immunohistochemical analysis of ER and screening programmes. ER status was unrelated to survival in patients with small, low grade, node-negative tumours which was no different from that expected for age-matched women taken from the general population. The value of adjuvant treatment in these patients is therefore questionable. In those given any adjuvant treatment, survival of women with ER+ tumours was prolonged, with the greatest effect being seen in those receiving Tam. Patients with ER- tumours benefited from CT but the addition of Tam to CT improved survival only in those with ER+ tumours. ER status is now established as a major predictive factor for treatment selection in primary disease. Studies of prognostic and predictive markers may be invalidated by use of adjuvant therapy and selection criteria for different treatments. Survival will be influenced by both tumour biology and therapy. This important consideration must be remembered when analysing new markers, particularly in small studies.  相似文献   
956.

Background

Association between esophageal achalasia/ gastroesophageal reflux disease (GERD) and cholelithiasis is not clear. Epidemiological data are controversial due to different methodologies applied, the regional differences and the number of patients involved. Results of concomitant cholecistectomy associated to surgical treatment of both diseases regarding safety is poorly understood.

Aim

To analyze the prevalence of cholelithiasis in patients with esophageal achalasia and gastroesophageal reflux submitted to cardiomyotomy or fundoplication. Also, to evaluate the safety of concomitant cholecistectomy.

Methods

Retrospective analysis of 1410 patients operated from 2000 to 2013. They were divided into two groups: patients with GERD submitted to laparocopic hiatoplasty plus Nissen fundoplication and patients with esophageal achalasia to laparoscopic cardiomyotomy plus partial fundoplication. It was collected epidemiological data, specific diagnosis and subgroups, the presence or absence of gallstones, surgical procedure, operative and clinical complications and mortality. All groups/subgroups were compared.

Results

From 1,229 patients with GERD or esophageal achalasia, submitted to laparoscopic cardiomyotomy or fundoplication, 138 (11.43%) had cholelitiasis, occurring more in females (2.38:1) with mean age of 50,27 years old. In 604 patients with GERD, 79 (13,08%) had cholelitiasis. Lower prevalence occurred in Barrett''s esophagus patients 7/105 (6.67%) (p=0.037). In 625 with esophageal achalasia, 59 (9.44%) had cholelitiasis, with no difference between chagasic and idiopathic forms (p=0.677). Complications of patients with or without cholecystectomy were similar in fundoplication and cardiomyotomy (p=0.78 and p=1.00).There was no mortality or complications related to cholecystectomy in this series.

Conclusions

Prevalence of cholelithiasis was higher in patients submitted to fundoplication (GERD). Patients with chagasic or idiopatic forms of achalasia had the same prevalence of cholelithiasis. Gallstones occurred more in GERD patients without Barrett''s esophagus. Simultaneous laparoscopic cholecystectomy was proved safe.  相似文献   
957.
958.
Characteristics of gentamicin resistance in nosocomial infections   总被引:2,自引:0,他引:2  
Characteristics of gentamicin resistance were studied in gram-negative bacilli from 50 consecutive patients with nosocomial infection, during a time when gentamicin resistance had recently become prevalent at Medical University Hospital. Burns, decubitus ulcers, and cystic fibrosis were common precipitating factors for acquisition of gentamicin-resistant organisms. Pseudomonas aeruginosa accounted for 76% and Enterobacteriaceae for 24% of isolates. There was high prevalence of cross-resistance to amikacin (61%) and tobramycin (58%). Of the P aeruginosa strains 36% possessed plasmids which were rapidly detected by agarose gel electrophoresis. None of the isolates transferred gentamicin resistance. Representative isolates failed to elaborate aminoglycoside-modifying enzymes or to take up labelled amikacin. Multiple immunotypes of P aeruginosa were identified. These data suggest that a nonplasmid mediated resistance mechanism such as impermeability was responsible for the emergence of gentamicin resistance.  相似文献   
959.

Statement of problem

Clinical data regarding newly introduced laser-sintered removable partial dentures (RPDs) are needed before this technique can be recommended. Currently, only a few clinical reports have been published, with no clinical studies.

Purpose

This clinical trial compared short-term satisfaction in patients wearing RPDs fabricated with conventional or computer-aided design and computer-aided manufacturing (CAD-CAM) laser-sintering technology.

Material and methods

Twelve participants with partial edentulism were enrolled in this pilot crossover double-blinded clinical trial. Participants were randomly assigned to wear cast or CAD-CAM laser-sintered RPDs for alternate periods of 30 days. The outcome of interest was patient satisfaction as measured using the McGill Denture Satisfaction Instrument. Assessments was conducted at 1, 2, and 4 weeks. The participant’s preference in regard to the type of prosthesis was assessed at the final evaluation. The linear mixed effects regression models for repeated measures were used to analyze the data, using the intention-to-treat principle. To assess the robustness of potential, incomplete adherence, sensitivity analyses were conducted.

Results

Statistically significant differences were found in patients’ satisfaction between the 2 methods of RPD fabrication. Participants were significantly more satisfied with laser-sintered prostheses than cast prostheses in regard to general satisfaction, ability to speak, ability to clean, comfort, ability to masticate, masticatory efficiency, and oral condition (P<.05). At the end of the study, 5 participants preferred the laser-sintered, 1 preferred the cast RPD, and 3 had no preference.

Conclusions

The use of CAD-CAM laser-sintering technology in the fabrication of removable partial dentures may lead to better outcomes in terms of patient satisfaction in the short term. The conclusion from this pilot study requires confirmation by a larger randomized controlled trial. Clinical Trial: ClinicalTrials.gov. A study about patient satisfaction with laser-sintered removable partial dentures; NCT02769715.  相似文献   
960.
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