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21.
Corynebacterium species that are normally abundant on the skin and mucous membranes rarely cause infections and are susceptible to most antibiotics. The report in 1976 of four cases of sepsis at the National Institutes of Health caused by a hitherto undescribed Corynebacterium that is highly antibiotic resistant, but uniformly susceptible to vancomycin, alerted the medically oriented scientific community to the emergence of these organisms as a possible new cause of nosocomial infections. Although we have always performed antibiotic susceptibility tests on all microorganisms recovered from normally sterile body fluids, our first recovery of these organisms was in August 1977. Since then we have recovered 52 such strains from 39 patients, most frequently from the rectum, followed by the groin, blood, lesions and urine in order of predominance. Characterization by API 50 L strips revealed that most, but not all strains resemble the JK group of Riley et al. [1]. Cell wall studies and DNA base ratios further confirmed their status as corynebacteria. Hospital acquisition has been proved; cross infection between patients is the most likely mode of spread. Their recognition is necessary for optimal preventive and therapeutic care of patients with compromised host defenses.  相似文献   
22.
In order to assess high-pressure barocepture sensitivity and parasympathetic function in elderly patients with silent myocardial ischemia, we selected 45 inpatients in our geriatric unit for a prospective cohort study of patients with coronary heart disease. All patients were over 65 years of age (37 men and 8 women) and had coronary heart disease, documented by an angiographic study and electrocardiographic evidence of myocardial ischemia during exercise stress testing, performed according to the Bruce protocol. The subjects were divided in three subgroups: group 1 (22 patients) with electrocardiographic and echocardiographic history of myocardial infarction but no angina chest pain during exercise testing; group 2 (13 patients) with no exercise induced chest pain; and group 3 (10 patients) with exercise-induced chest pain. Baroceptor sensitivity was assessed in all subjects, by evaluating heart rate changes expressed in RR interval on the basis of changes in the mean arterial pressure during intravenous infusion of stepwise doses (50-100 and 150 mug) of phenylephrine hydrochloride. Heart rate changes were also evaluated during overshoot of the Valsalva maneuver (Valsalva max.), providing an index of parasympathetic activity. Our results showed that group two patients (only silent ischemia) had significantly (P>0.001) greater baroceptor sensitivity than the other two groups (group 2; 15.2+/-1.9 ms/mmHg; group 1: 10.0+/-1.7 ms/mmHg; and group 3: 9.8+/-1.7 ms/mmHg). Group two also showed a significant positive correlation (r=0.58; P<0.05) between baroceptor sensitivity and end-diastolic pressure and a significant inverse correlation (r=-0.672; P<0.05) between baroceptor sensitivity and the ejection fraction. Group 2 patients had a significantly longer RR interval than group 1 (P<0.05) and group 3 (P<0.05); a significant positive correlation (r=0.620; P<0.05) between Valsalva max. and end-diastolic pressure; and a significant inverse correlation (r=0.694; P<0.05) between Valsalva max. and the ejection fraction. Valsalva max. and baroceptor sensitivity correlated significantly in all three groups (group 1, r=0.707; P<0.001; group 2, r=0.94; P<0.001; and group 3; r=0.833; P<0.05). In conclusion our data suggest that elderly patients with silent ischemia appear to have an increased capacity for evoking parasympathetic reflexes that could inhibit pain perception.  相似文献   
23.
PURPOSE: The present prospective, randomized clinical trial compares the outcome of surgical hemorrhoidectomy according to Parks and Milligan-Morgan in terms of hospital stay, duration of incapacity to work, symptom relief, length of morbidity, and patient convenience. METHODS: Thirty-four consecutive patients with third or fourth degree internal hemorrhoids were randomly allocated to the two groups. Before surgery, all patients were interviewed using a standard questionnaire, followed by rectal examination. All patients underwent a follow-up interview and examinations 1, 2, 4, 8, and 12 weeks after the operation. RESULTS: No serious postoperative complications were seen. Length of hospital stay (3.2 days for Parks hemorrhoidectomyvs. 4.6 days for Milligan-Morgan hemorrhoidectomy; 95 percent confidence interval, 0.2 and 2.6, respectively;P=0.02) and mean duration of incapacity to work (12.3 days for Parks hemorrhoidectomyvs. 20.2 days for Milligan-Morgan hemorrhoidectomy; 95 percent confidence interval, 5.7 and 10.2, respectively;P<0.001) differed significantly between the Milligan-Morgan and Parks patients. Until two weeks after the operation, Milligan-Morgan hemorrhoidectomy patients experienced significantly more pain. CONCLUSIONS: Our study confirms that both operations are safe, easy to perform, and lead to satisfactory results. However, the Parks procedure is the preferred option, because it minimizes patients' postoperative discomfort, is more economic, has a significantly reduced hospital stay, and has a shorter time for return to work.  相似文献   
24.
ObjectivesThis study sought to determine whether the breast gland adipose tissue is associated with different rates of major adverse cardiac events (MACEs) in pre-menopausal women.BackgroundTo our knowledge, no study investigated the impact of breast adipose tissue infiltration on MACEs in pre-menopausal women.MethodsProspective multicenter cohort study conducted on pre-menopausal women >40 years of age without cardiovascular disease and breast cancer at enrollment. The study started in January 2000 and ended in January 2009, and the end of the follow-up for the evaluation of MACEs was in January 2019. Participants underwent mammography to evaluate breast density and were divided into 4 groups according to their breast density. The primary endpoint was the probability of a MACE at 10 years of follow-up in patients staged for different breast deposition/adipose tissue deposition.ResultsThe propensity score matching divided the baseline population of 16,763 pre-menopausal women, leaving 3,272 women according to the category of breast density from A to D. These women were assigned to 4 groups of the study according to baseline breast density. At 10 years of follow-up, we had 160 MACEs in group 1, 62 MACEs in group 2, 27 MACEs in group 3, and 16 MACEs in group 4. MACEs were predicted by the initial diagnosis of lowest breast density (hazard ratio: 3.483; 95% confidence interval: 1.476 to 8.257). Further randomized clinical trials are needed to translate the results of the present study into clinical practice. The loss of ex vivo breast density models to study the cellular/molecular pathways implied in MACE is another study limitation.ConclusionsAmong pre-menopausal women, a higher evidence of adipose tissue at the level of breast gland (lowest breast density, category A) versus higher breast density shows higher rates of MACEs. Therefore, the screening mammography could be proposed in overweight women to stage breast density and to predict MACEs. (Breast Density in Pre-menopausal Women Is Predictive of Cardiovascular Outcomes at 10 Years of Follow-Up [BRECARD]; NCT03779217)  相似文献   
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26.
Maternal malnutrition during gestation and lactation is known to have adverse effects on offspring. We evaluate the impact of maternal diet on offspring bony labyrinth morphology. The bony labyrinth develops early and is thought to be stable to protect vital sensory organs within. For these reasons, bony labyrinth morphology has been used extensively to assess locomotion, hearing function, and phylogeny in primates and numerous other taxa. While variation related to these parameters has been documented, there is still a component of intraspecific variation that is unexplained. Although the labyrinthine developmental window is small, it may provide the opportunity for developmental instability to produce corresponding shape differences, as measured by fluctuating asymmetry (FA). We hypothesized that (a) offspring with poor maternal diet would exhibit increased FA, but (b) no unilateral shape difference. To test these hypotheses, we used two groups of rats (Rattus norvegicus; Crl:WI[Han] strain), one control group and one group exposed to a isocaloric, protein-restricted maternal diet during gestation and suckling. Individuals were sampled at weaning, sexual maturity, and old age. A Procrustes analysis of variance identified statistically significant FA in all diet-age subgroups. No differences in level of FA were identified among the subgroups, rejecting our first hypothesis. A principal components analysis identified no unilateral shape differences, supporting our second hypothesis. These results indicate that bony labyrinth morphology is remarkably stable and likely protected from a poor maternal diet during development. In light of this result, other factors must be explored to explain intraspecific variation in labyrinthine shape.  相似文献   
27.
We propose a new algorithm, based on a linear regression model, to statistically estimate the hemodynamic activations in fNIRS data sets. The main concern guiding the algorithm development was the minimization of assumptions and approximations made on the data set for the application of statistical tests. Further, we propose a K-means method to cluster fNIRS data (i.e. channels) as activated or not activated. The methods were validated both on simulated and in vivo fNIRS data. A time domain (TD) fNIRS technique was preferred because of its high performances in discriminating cortical activation and superficial physiological changes. However, the proposed method is also applicable to continuous wave or frequency domain fNIRS data sets.OCIS codes: (000.5490) Probability theory, stochastic processes, and statistics; (170.2655) Functional monitoring and imaging; (170.6920) Time-resolved imaging; (170.1470) Blood or tissue constituent monitoring  相似文献   
28.
BACKGROUND: Disability in older adults is thought to occur primarily as a consequence of clinical disease episodes. However, the temporal relationship between clinical disease and disability has received little systematic attention. METHODS: Data from a prospective population-based study of 2812 older adults were analyzed to examine changes in disability before and after acute myocardial infarction. Disability outcomes included up to 9 yearly assessments of disability in activities in daily living, disability in basic physical functions, and disability in tasks requiring basic mobility and strength. RESULTS: A total of 279 myocardial infarctions occurred during 9 years of follow-up. After adjustment for age and sex, the average yearly increase in disability in activities of daily living and basic physical functions was not significantly greater in the 1-year period after myocardial infarction than in the 3-year period before myocardial infarction (P values >.20). Disability in basic mobility and strength showed a significantly greater increase in the year after myocardial infarction (P = .02). The results did not change after adjustment for comorbidity and chest pain or when restricted to incident cases of myocardial infarction or survivors. An additional exploratory analysis suggested that the rate of increase in some forms of disability may start to accelerate at about 1 year before the event, rather than after the event. CONCLUSIONS: The increase in disability after myocardial infarction may form a continuation of increases that occur before the event and challenge commonly held notions about the temporal relationship between clinical disease and disability. Changes in disability before acute disease episodes may be related to subclinical disease.  相似文献   
29.
BackgroundThymoma is a rare mediastinal neoplasia. Surgery is the backbone of the treatment, but the role of postoperative radiotherapy (PORT) remains controversial. We aimed to obtain data on survival and safety in patients treated with PORT in three different Italian institutions.MethodsWe retrospectively analyzed 183 consecutive patients who underwent surgery from 1981 to 2015. According to the Masaoka-Koga staging system, 39.3%, 32.7%, 18.6% and 9.8% patients were in stage I, II, III and IV of disease, respectively. PORT was indicated in 114 patients (62.3%), while 69 subjects underwent surgery alone. Complete resection was obtained in 68 patients who underwent PORT. Adverse events (AEs) were graded according to CTCAE v4.0. We analyzed the recent literature to describe the current reports on PORT for resected thymoma.ResultsMean follow-up was 130 months (range, 3–417 months). Overall survival (OS) at 1-, 5- and 10-year from surgery was 98.3%, 90.2% and 69.7% respectively. One-, 5- and 10-year disease specific survival (DSS) was 98.9%, 92.3% and 89.8% respectively. Disease free survival (DFS) at 1, 5 and 10 years from surgery was 96.7%, 88.3% and 82.8% respectively. Univariate analysis showed that complete resection, cell histology A-AB-B1 and stages I–II were significant predictors of better DSS and DFS. Multivariate analysis showed that sex, R0 margins and WHO histology was independent prognostic factors. Among patients treated with PORT, a trend towards better OS was evident with Masaoka stage I–II (P=0.09). Patients with R0 margins treated with PORT showed better OS and DSS (P=0.05). No differences in DSS for performance status (P=0.70), WHO histology (P=0.19), paraneoplastic syndrome (P=0.23) and surgical procedure (P=0.53) were evident. Patients treated with PORT had a higher level of acute AEs compared to surgery alone, but none of these was graded ≥3.ConclusionsOur results confirmed that patients with incompletely resected thymoma had the worst OS and DSS. High grade acute toxicity was not different between PORT and surgery alone. Other trials reported a significant benefit in OS, DSS and DFS in stage IIb–IV thymoma treated with PORT.  相似文献   
30.
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