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31.
原发性乳腺恶性淋巴瘤六例临床分析 总被引:8,自引:0,他引:8
目的 分析原发性乳腺恶性淋巴瘤的临床特点,探讨其诊断、分期和治疗方法。方法回顾分析我院自1995~2002年收治的6例原发性乳腺恶性淋巴瘤和1980~2002年国内主要文献报道的279例原发性乳腺恶性淋巴瘤的临床特征、诊断情况和治疗方法,进行对比分析。结果 285例病例均为非霍奇金淋巴瘤(NHL),免疫学检查证实有282例为B细胞源性(98.9%);女性268例,占94.0%;病灶位于右侧163例,占57.2%;Ⅰ期和Ⅱ期的原发性乳腺恶性淋巴瘤占89.8%。经手术、化疗、放疗等综合治疗后,生存期2~206个月,中位生存期最短23个月,最长56个月。结论 原发性乳腺恶性淋巴瘤绝大部分为B细胞源性非霍奇金淋巴瘤(NHL),Ⅰ期、Ⅱ期多见。对于原发性乳腺恶性淋巴瘤,诊断是关键,确诊后经手术、化疗、放疗等综合治疗,可以获得较长的生存期,疗效十分满意。 相似文献
32.
Chemolysis of urinary calculi 总被引:1,自引:0,他引:1
Irrigant chemolysis was developed to collaborate with open surgery, removing the residual fragments. With the worldwide diffusion of the procedures performed by the endourologist in the early 1980s and the present availability of ESWL, however, direct irrigation of stones has a reduced field of influence even as an adjunctive measure. Urologists have applied economic analysis to their clinical practices, and the findings related to irrigant chemolysis made this technique an unusual procedure. The cost to the providers of medical care, the burden on the patient in terms of suffering and loss of productivity, and the amount of time required to liberate the patient even partially from the stones make irrigant chemolysis an inauspicious scenario. In this era of cost containment and decreasing length of stay, it is increasingly difficult to justify hospital admissions for this form of therapy. Being simultaneously more expensive and less effective than the existing alternatives, local chemolysis should be discarded, except for special situations, such as patients at high risk for any surgical procedure. Oral chemolysis preserves reduced indications, for example as an adjuvant to an endourologic operation or ESWL in special situations. As long as urinary stones continue to afflict humans, chemolysis is likely to retain a limited but important role in their management. 相似文献
33.
L Patel PE Clayton ME Jenney JE Ferguson TJ David 《Archives of disease in childhood》1997,76(6):505-508
Cross sectional studies have reported impaired growth in children with atopic dermatitis. If this growth impairment is irreversible, it would be expected to adversely influence final height attainment. The standing heights and other anthropometric parameters were assessed in 35 adults with onset of atopic dermatitis before 5 years of age and a control group of 35 adults with adult onset contact dermatitis or psoriasis. There was no significant difference in the standing height SD score, mid-parental height SD score, sitting height SD score, subischial leg length SD score, nor body mass index between the atopic dermatitis and control groups. The standing height SD score was not significantly different among: (a) patients with atopic dermatitis affecting less than 50% of their body surface area and those with greater than 50% affected; (b) patients using the four different potency topical corticosteroids; and (c) patients with atopic dermatitis without asthma and those with coexisting asthma. It is concluded that short stature is not a feature of our group of adult patients with onset of atopic dermatitis before 5 years of age, continuing into adulthood, and severe enough to require specialist care. This suggests that if growth impairment occurs in childhood, it is likely to be temporary and reversible. 相似文献
34.
The relationship between psychopathology and Wisconsin Card Sorting Test (WCST) performance was evaluated in 25 unmedicated young acute schizophrenic female patients (14 neuroleptic-naive and 11 neuroleptic-free) and 15 female controls. The schizophrenic patients (especially the neuroleptic-free) performed more poorly than controls in the WCST. In addition, WCST impairment correlated with both negative and positive symptoms. The results suggest that the neuropsychological dysfunction in schizophrenia is present at the onset of the illness, and is neither secondary to previous neuroleptic treatment nor to chronicity of the illness. 相似文献
35.
Bernardo L. Teixeira Joo Cabral Andr Marques-Pinto Fernando Vila Joaquim Lindoro Avelino Fraga 《Canadian Urological Association journal》2022,16(5):E267
IntroductionWe aimed to compare the rate of postoperative infection and drug-resistant organism (DRO) before and during the COVID-19 pandemic in urology departments.MethodsA retrospective cohort study was carried out. Data from all elective surgical procedures carried out in two urology departments between April and June 2018 and the homologous period in 2020 were collected. Main outcomes were the number of postoperative infections during the pandemic and the number of DROs. Sample size was calculated based on a 50% relative reduction of infections during the pandemic. Variables were compared by Chi-squared test, and multivariable logistic regression was used to estimate predictors.ResultsA total of 698 patients undergoing elective surgery were included. The postoperative infection rate during the pre-pandemic period was of 14.1% compared to 12.1% during the pandemic (p=0.494). DROs were lower during the pandemic (92.3% vs. 52.4%, p=0.002). The pandemic period was the main predictor for reduced multidrug-resistant isolates, with an odds ratio of 0.10 (p=0.010, 95% confidence interval 0.016–0.57).ConclusionsPostoperative infection rates were not significantly reduced during the COVID-19 pandemic, despite the adoption of enhanced infection preventive measures. There was, however, a decrease in the rate of DROs during this period, suggesting a secondary benefit to enhanced infection prevention practices adopted during the COVID-19 era. 相似文献
36.
Matthew D. Li Nishanth T. Arun Mehak Aggarwal Sharut Gupta Praveer Singh Brent P. Little Dexter P. Mendoza Gustavo C.A. Corradi Marcelo S. Takahashi Suely F. Ferraciolli Marc D. Succi Min Lang Bernardo C. Bizzo Ittai Dayan Felipe C. Kitamura Jayashree Kalpathy-Cramer 《Medicine》2022,101(29)
To tune and test the generalizability of a deep learning-based model for assessment of COVID-19 lung disease severity on chest radiographs (CXRs) from different patient populations.A published convolutional Siamese neural network-based model previously trained on hospitalized patients with COVID-19 was tuned using 250 outpatient CXRs. This model produces a quantitative measure of COVID-19 lung disease severity (pulmonary x-ray severity (PXS) score). The model was evaluated on CXRs from 4 test sets, including 3 from the United States (patients hospitalized at an academic medical center (N = 154), patients hospitalized at a community hospital (N = 113), and outpatients (N = 108)) and 1 from Brazil (patients at an academic medical center emergency department (N = 303)). Radiologists from both countries independently assigned reference standard CXR severity scores, which were correlated with the PXS scores as a measure of model performance (Pearson R). The Uniform Manifold Approximation and Projection (UMAP) technique was used to visualize the neural network results.Tuning the deep learning model with outpatient data showed high model performance in 2 United States hospitalized patient datasets (R = 0.88 and R = 0.90, compared to baseline R = 0.86). Model performance was similar, though slightly lower, when tested on the United States outpatient and Brazil emergency department datasets (R = 0.86 and R = 0.85, respectively). UMAP showed that the model learned disease severity information that generalized across test sets.A deep learning model that extracts a COVID-19 severity score on CXRs showed generalizable performance across multiple populations from 2 continents, including outpatients and hospitalized patients. 相似文献
37.
Akansha Mehta Khaoula Karbouche Jozef Kraxner Hamada Elsayed Duan Galusek Enrico Bernardo 《Materials》2022,15(11)
The present COVID-19 emergency has dramatically increased the demand for pharmaceutical containers, especially vials. End-of-life containers, however, cannot be easily recycled in the manufacturing of new articles. This paper presents some strategies for upcycling of pharmaceutical glass into various porous ceramics. Suspensions of a fine glass powder (70 vol%) are used as a starting material. Highly uniform cellular structures may be easily prepared by vigorous mechanical stirring of partially gelified suspensions with added surfactant, followed by drying and firing at 550–650 °C. Stabilization of the cellular structures at temperatures as low as the glass transition temperature (Tg) of the used glass is facilitated by thermal decomposition of the gel phase, instead of viscous flow sintering of glass. This finding enabled the preparation of glass membranes (∼78 vol% open porosity), by direct firing of hardened suspensions, avoiding any surfactant addition and mechanical stirring. The powders obtained by crushing of hardened suspensions, even in unfired state, may be used as a low-cost sorbent for dye removal. 相似文献
38.
Silvia Ferri Bernardo Stefanini Lorenzo Mulazzani Margherita Alvisi Francesco Tovoli Simona Leoni Luca Muratori Tommaso Lotti Alessandro Granito Luigi Bolondi Fabio Piscaglia 《Nutrients》2022,14(12)
The role of moderate alcohol consumption in the evolution of NAFLD is still debated. The aim of this study is to evaluate the impact of current and lifelong alcohol consumption in patients with NAFLD. From 2015 to 2020, we enrolled 276 consecutive patients fulfilling criteria of NAFLD (alcohol consumption up to 140 g/week for women and 210 g/week for men). According to their current alcohol intake per week, patients were divided in: abstainers, very low consumers (C1: <70 g/week) and moderate consumers (C2). We created a new tool, called LACU (Lifetime Alcohol Consuming Unit) to estimate the alcohol exposure across lifetime: 1 LACU was defined as 7 alcohol units per week for 1 drinking year. Patients were divided into lifelong abstainers and consumers and the latter furtherly divided into quartiles: Q1-Q4. Stratification according to alcohol intake, both current and cumulative as estimated by LACU, showed that very low consumers (C1 and Q1-Q3) displayed lower frequency of cirrhosis and hepatocellular carcinoma compared to abstainers and moderate consumers (C2 and Q4). We can speculate that up to one glass of wine daily in the context of a Mediterranean diet may be a long-term useful approach in selected NAFLD patients. 相似文献
39.
Public health implications of opening National Football League stadiums during the COVID-19 pandemic
Bernardo García Bulle Dennis Shen Devavrat Shah Anette E. Hosoi 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(14)
Using attendance data from the 2020 National Football League (NFL) regular season and local COVID-19 case counts, we estimate the public health impact of opening NFL stadiums to fans during the COVID-19 pandemic. Data are analyzed using robust synthetic control, a statistical method that is employed to obtain counterfactual estimates from observational data. Unlike previous studies [J. Kurland et al., SSRN, 2021], which do not consider confounding factors such as evolving policy landscapes in different states, the synthetic control methodology allows us to account for effects that are county specific and may be changing over time. We find it is likely that opening stadiums had no impact on local COVID-19 case counts; this suggests that, for the 2020 NFL season, the benefits of providing a tightly controlled outdoor spectating environment—including masking and distancing requirements—counterbalanced the risks associated with opening. These results are specific to the 2020 NFL season, and care should be taken in generalizing our conclusions. In particular, 1) these data reflect a period during which earlier strains of COVID-19 were dominant prior to the emergence of more-transmissive strains such as the Delta and Omicron variants, and 2) the data are restricted to outdoor environments; hence our results cannot be applied to small indoor spaces where transmission-restricting controls are essential.A year and a half into the global COVID-19 pandemic, we have an opportunity to analyze and reflect upon the policies and decisions enacted over the past 18 mo. Given the distributed nature of policy decisions in the United States, we find ourselves in a unique position in which states and municipalities have explored different strategies to combat the virus, and the efficacy of those policies has been imprinted in the local case counts, hospitalizations, and death records. In particular, these data contain a wealth of information about which policies have proven to be effective in preserving the health and safety of our communities.One activity that one may wish to consider is the opening of outdoor sporting events to spectators. This question has recently generated quite a bit of interest as ballparks across the nation open for summer and events such as the 2021 Summer Olympics in Japan take place.* On the one hand, governing bodies are naturally wary of opening stadiums given the well-documented importance of avoiding large gatherings. On the other hand, sporting events are often held outdoors, where airflow is largely unobstructed (1), and in venues where crowd density can be carefully controlled if the event is properly managed. In the absence of a detailed analysis, it is not immediately obvious which of these effects dominates.Data from the National Football League (NFL) may provide an answer to this question. During the 2020 regular season, teams in the NFL collaborated with local communities to determine whether or not to allow fans in the stadiums during the pandemic. In general, stadiums that opened their doors to fans adopted pandemic requirements for all in attendance (1), which typically include some combination of staggered entry, required masking, health questionnaires, temperature checks for staff, deployment of compliance officers, modified concessions, social distancing in seating and lines, mobile ticketing, enhanced cleaning protocols, amplified health and safety communications, and capacity limitations. The highest capacity that any NFL stadium allowed during the 2020 regular season was 30% (Dallas), with most other stadiums considerably below that limit (2). These policy decisions were made based on local guidelines, local prevalence, community risk tolerance, and other localized considerations; some stadiums ultimately decided to allow fans at the games, while others remained closed, providing perhaps the first set of natural experiments that can be analyzed to investigate the impact of opening stadiums on COVID-19 case rates. In the words of Kurland et al. (3), who recently provided a first look at this data, “Scant evidence has been gathered in the extant literature on the impact of sport venues on local public health, influenza-related mortality rates, or disease contagion more generally. There is a complete absence of any evidence related to the impact of fans gathering at sporting events, or mass gatherings more generally, on incidence of COVID-19 at the local-level.” The natural experiments from the 2020 NFL season and other sports leagues present a golden opportunity to address these questions in the context of the original 2020 COVID-19 strain (4, 5).In the Kurland et al. (3) study, the authors compared COVID-19 case data from NFL stadium counties that allowed fans in the stadium to counties that did not allow fans, and looked for spikes in the data in the weeks following a game; the authors concluded, from this analysis, that the presence of large numbers of fans at NFL games led to “tangible increases” in the local incidence of COVID-19 cases. However, this type of analysis may be problematic: In this context, the control stadiums (i.e., those without fans) tend to be embedded in states with stricter COVID-19 policies—rather than a random control—so the sample of control counties is strongly biased. New York and Dallas, for example, are immersed in very different environments with different pandemic policies, and it is not at all obvious that one can attribute the differences in case spikes to the stadiums, given the enormous number of confounding factors.Fortunately, there exists a rich literature of techniques—longitudinal methods, hierarchical methods, factor model methods, synthetic control, etc.—that we can draw upon to account for these confounding factors. In this particular analysis, we turn to synthetic control (6–9), which has been applied in a diversity of fields—criminology (10), healthcare (11), sports (12), and political science and policy evaluation (13–15), to name a few. At its heart, synthetic control is a method for estimating a counterfactual in the absence of an intervention, in this case, what would have happened if stadiums had not opened. The method provides a systematic way to choose relevant comparison units when randomized controls are not available.To illustrate the power of synthetic control, imagine the ideal experiment one would like to run in order to quantify the impact of opening the Dallas stadium to fans. In principle, we would like to have COVID-19 case counts from Dallas County throughout the season with the stadium open to fans and case counts from a Dallas twin—with identical people and policies to the first Dallas—in which the stadium did not open for comparison. The first set of data (Dallas open to fans) is readily available. The second set of data can be constructed from information from other counties in Texas—hereafter referred to as donor counties—which have policies and characteristics similar to Dallas. Synthetic control provides a methodology to build a weighted combination of these Dallas-like counties, which can then be used as a control group, that is, a “synthetic” Dallas twin. In particular, we seek the linear combination of case counts from other Texas counties that most closely mirrors the Dallas case counts prior to the stadium opening. Given that none of these non-Dallas counties have a stadium, this linear combination can be extended postintervention (i.e., after opening the stadium) to estimate what would have happened in the synthetic Dallas in which no stadium opened. Once it has been established that the stadium county and the synthetically generated county have similar behavior over extended periods of time prior to the intervention, a discrepancy in the number of COVID-19 cases following the intervention may be interpreted as a result of allowing fans in the stadium. One of the advantages of this method is that it can account for the effects of confounding factors that are county specific and may be changing over time, which is crucial in the ever-evolving policy landscape of a pandemic (16). In particular, our methodology allows for correlation between the decision to open the stadium and characteristics that define the county (cultural or political leaning, population density, demographics, etc.), but cannot account for correlations between the decision and exogenous noise.At this point, it is reasonable to speculate whether one should expect linear combinations of donor counties to accurately represent stadium counties (both observed and counterfactual). In general, assuming linearity is appropriate provided there exists an underlying low-dimensional structure to the case count data, that is, if the matrix containing discretized time series of donor county case counts is approximately low rank. Under a such a setting, linearity between counties is an almost immediate consequence (see Materials and Methods for details). This low-rank assumption is common in the matrix completion literature; notably, low-rank matrices have also been shown to naturally arise in modern datasets and emerge from “well-behaved” generative models (e.g., Lipschitz functions) (17–20). This point will be revisited in Results, where we test for low rankedness empirically in the context of our dataset.Finally, the selection of donor units is a critical step in the successful implementation of creating a synthetic control. In particular, donor units (in our case, counties) should have the following characteristics:
- 1)Counties affected by the intervention or by events of a similar nature should be excluded from the donor pool.
- 2)Counties that may have suffered large “idiosyncratic shocks” (7, 21) during the preintervention period should be excluded.
- 3)The donor pool should be restricted to counties with characteristics similar to the stadium county; in this case, we restrict our pool to counties from the same state to maintain some consistency in COVID-19 policies.
- 4)Case counts that cover an extended period of time prior to the intervention are required for both stadium counties and donor counties.
40.
María Espinosa-Bosch Bernardo Santos-Ramos María Victoria Gil-Navarro María Dolores Santos-Rubio Roberto Marín-Gil Paloma Villacorta-Linaza 《International journal of clinical pharmacy》2012,34(6):807-817
Aim of the review To study the prevalence of drug interactions in hospital healthcare by reviewing literature. Method A review was carried out of studies written in Spanish and English on the prevalence of drug interactions in hospital care published in Pubmed between January 1990 and September 2008. The search strategy combined free text and MeSH terms, using the following keywords: ??Drug interaction??, ??prevalence?? and ??hospital??. For each article, we classified independent variables (pathology, age of population, whether patients were hospitalized or not, geographical location, etc.) and dependent variables (number of interactions per 100 patients studied, prevalence of patients with interactions, most common drug interactions, and others). Results The search generated 436 articles. Finally, 47 articles were selected for the study, 3 provided results about drug interactions with real clinical consequences, 42 about potential interactions, and 2 described both. The prevalence of patients with interactions was between 15 and 45?% and the number of interactions per 100 patients was between 37 and 106, depending on the group of studies analyzed. There was a considerable increase in these rates in patients with heart diseases and elderly persons. Conclusion There is a large number of studies on the prevalence of drug interactions in hospitals but they report widely varying results. The prevalence is higher in patients with heart diseases and elderly people. 相似文献