重症监护病房病原菌分布调查及护理对策

目的 调查杭州市第三人民医院重症监护病房(ICL)病原菌的分布,耐药性情况及控制措施.方法 对该院ICU 2009年1月至2010年7月期间所分离病原菌的菌群分布及其耐药情况进行回顾性分析.根据结果制定相应的护理对策.结果 共分离出病原菌2 694株,以革兰阴性杆菌为主,占73.2％,其中比例最高的为鲍曼不动杆菌(21.9％),其次为铜绿假单胞菌(16.8％).革兰阳性球菌占16.5％,比例最高为金黄色葡萄球菌(10.3％).真菌占10.3％.结论 革兰阴性杆菌仍为ICU主要病原菌,且呈现多重耐药趋势,制定有效的防治对策十分重要.     

The distribution of Heterotrissocladius oliveri Saether (Diptera: Chironomidae) in Lake Michigan

Fifty one chironomid species were identified from 504 samples collected at depths ranging 8 to 267 m in Lake Michigan, U.S.A. Heterotrissocladius oliveri Saether occurred in 32% of these samples and had an average abundance of 22 m^–2 which was similar to other estimates from the Great Lakes. Maximum average lake-wide density was at 30 to 60 m (41 m^–2). At depths 60 m, H. oliveri was the dominant chironomid species comprising 75% of total Chironomidae. The substrate preference of H. oliveri differed within each depth regime considered: at 30–60 m, 2–3 ; at 60–120 m, 3–5 , 7–9 ; and at 120–180 m, 6–8 . Abundance was notably reduced at all depths in substrates characterized as medium silt (5–6 ). On a lake-wide basis, the distribution pattern suggested H. oliveri was most numerous from 30 to 60 m along the southwestern, eastern, and northern shorelines and at 60–120 m depths along the southern and eastern shorelines. Increased abundance in the South Basin was concurrent with evidence of increased sedimentation at 60 to 100 m. However, in several other areas of the lake, high densities were associated with medium to very fine sands relatively free of silts and clays. This observation suggested occurrence of H. oliveri was minimally affected by sediment type.Widely variable, but generally elevated water temperatures likely prevent H. oliveri from establishing a substantial population density at depths < 30 m. With increased depth, temperature fluctuation is negligible and food is more stable, though the source is variable. Factors limiting abundance of H. oliveri at depths 30 m were related to decreased food supply due to distance from shore, food sources of lower value (clays), and, most importantly, to reproductive replenishment.Although still oligotrophic in nature, high density occurrences in both high and low sedimentation areas of the lake suggest the trophic indicator status of H. oliveri might be broader than previously thought.     

The role of flow cytometry in medical mycology

The alarming increase in fungal diseases among hospitalized patients is a serious problem as these infections often have poor prognosis because of delayed diagnosis and lack of proper therapy. The rapid laboratory diagnosis of these diseases still remains problematic. The areas of concern include accurate identification of pathogenic fungi, rapid testing of their susceptibility to antifungals, and reliable determination of their interrelatedness to other clinical isolates. In the past few decades, flow cytometry has proven to be an adaptive technology platform for diagnostics. The applications encompass identification, serotyping, genotyping, susceptibility testing, and molecular pathogenesis studies. The recent revolution in the miniaturizing and customizing of instrumentation has now made this technology more accessible and affordable. In the near future, it is imperative to develop standardized protocols by means of interlaboratory comparisons and to share reagents for reproducibility studies. Flow cytometry remains highly attractive as an integrated application for myriad tasks in medical mycology laboratories.     

Forest distribution and site quality in southern Lower Michigan, USA

Aim The primary objectives of this research were to determine whether current forest patches in southern Lower Michigan are a proportionate sample of forest types present in the pre‐settlement cover and, if not, to establish the degree to which certain types are over‐ or under‐represented in the contemporary landscape. This determination is useful not only because any conservation policy designed to restore the present forest to pre‐settlement biodiversity through preservation of existing stands requires an accurate understanding of the degree to which these stands in sum mirror past forest diversity, but also because it fills a gap in the existing ecological literature. Location The research was conducted within four counties in southern Lower Michigan, USA (Ionia, Livingston, Tuscola and Van Buren). Methods Soil survey data were used to characterize the range of site quality across the study area and the areal extent of each quality category. The geographic locations of all current forest patches in each county were then determined from land use maps and were overlaid on the site quality classification. This procedure yielded the observed distribution of forest relative to site quality. The expected areal extent of forest within each category of site quality on the landscape was determined by assuming a random distribution and multiplying the total area of forestland by the proportion of landscape within each category of site quality. This procedure calculated the expected distribution of forest in terms of site quality by dividing the total forestland among the landscape types, relative to how well represented the landscape types were. The observed and expected distributions were then compared both in terms of absolute difference and normalized difference. Results Overall results indicate that categories of site quality that support a large proportion of the present‐day forest patches are generally composed of agriculturally inferior soil and are over‐represented with forest. Surviving or reforested tracts are concentrated on inferior types of habitat. Main conclusions Results suggest that the present‐day forest patches may not be a proportionate sample of the primeval forest. Rather, they are concentrated on agriculturally‐inferior (coarse‐textured, steeply‐sloped, or poorly‐drained) types of habitat. Unless these stands are for some unknown reason compositionally richer than their pre‐settlement counterparts, these results suggest that the existing forest resource in southern Lower Michigan is an inferior (biased) sample of the primeval cover. Furthermore, because forest types associated with the most heavily‐developed agricultural sites have apparently suffered the most loss of habitat, species more characteristic of these types may have experienced a greater decline in overall importance across the landscape. This study suggests that policy aimed at increasing the potential biodiversity of the area should include provisions that encourage the redevelopment of forest habitat on those sites no longer supporting their equal share of forest.     

The role of analytical sciences in medical systems biology

Medical systems biology has generated widespread interest because of its bold conception and exciting potential, but the field is still in its infancy. Although there has been tremendous progress achieved recently in generating, integrating and analysing data in the medical and pharmaceutical field, many challenges remain, especially with respect to the crucial core technologies required for analytical characterization. This review briefly summarizes these aspects for metabolomics, proteomics, data handling and multivariate biostatistics.     

The role of nuclear magnetic resonance in medical mycology

With the continued emergence of drug-resistant invasive mycoses, rapid fungal identification and susceptibility testing are needed. Nuclear magnetic resonance (NMR) spectroscopy generates complex data (“fingerprints”) based on chemical composition and metabolite profiles, which can be applied to suspensions of living microorganisms or mammalian cells, cell and tissue extracts, biological fluids, tissue biopsies, and noninvasive diagnosis in patients when linked to MRI. Closely related fungal species can be rapidly identified based on their NMR spectra, and antifungal drug effects can be measured as metabolic end points. The feasibility of classifying groups of microorganisms directly from biological samples has been demonstrated in animal models and human infections. Potential advantages of NMR spectroscopy in medical mycology include accurate identification, automated sample delivery, automated analysis using computer-based methods, rapid turnaround time, high throughput, and low running costs. More work is needed to validate the automated approach on large data sets covering a broad spectrum of potential pathogens.     

Editorial: The role of medical physics in lung SBRT

Stereotactic body radiation therapy (SBRT) has become a standard treatment for non-operable patients with early stage non-small cell lung cancer (NSCLC). In this context, medical physics community has largely helped in the starting and the growth of this technique. In fact, SBRT requires the convergence of many different features for delivering large doses in few fractions to small moving target in an heterogeneous medium. The special issue of last month, was focused on the different physics challenges in lung SBRT. Eleven reviews were presented, covering: imaging for treatment planning and for treatment assessment; dosimetry and planning optimization; treatment delivery possibilities; image guidance during delivery; radiobiology. The current cutting edge role of medical physics was reported. We aimed to give a complete overview of different aspects of lung SBRT that would be of interest to both physicists implementing this technique in their institutions and more experienced physicists that would be inspired to start research projects in areas that still need further developments. We also feel that the role that medical physicists have played in the development and safe implementation of SBRT, particularly in lung region, can be taken as an excellent example to be translated to other areas, not only in Radiation Oncology but also in other health sectors.     

The clinical psychologist; his role in private medical practice

The independent diagnosis and treatment of mental and nervous disorders according to California law constitutes practicing medicine. By this yardstick, an increasing number of clinical psychologists are entering the private practice of medicine. The medical profession has not provided through its leadership the opportunity for clinical psychologists to utilize their skills in a legitimate and supervised way in the treatment of private patients, nor has the medical profession taken sufficient interest in modern methods of treating patients with psychogenic disorders. If the psychiatric team is a feasible and practical approach to spreading the base of psychiatric treatment in hospitals and clinics, it should be applicable to private practice settings too. In the team setting, the psychologist can render great assistance to the physician in the diagnosis and treatment of patients with psychogenic disorders without compromising the principle that the primary responsibility for the patient is the physician's. By virtue of his training and experience, it is the psychiatrist who is best qualified to supervise the work of the psychologist; and until such time as the medical profession is better acquainted with psychotherapeutic techniques, the employment of psychologist assistants should be (according to good medical practice) left to the psychiatrist. The need for some regulation of the use of the title "psychologist" is increasing in order to protect the public from quacks who pose as psychologists. However, any law which is directed toward elimination of the quack should specifically define psychotherapy and contain provisions for its use under adequate medical supervision. The medical profession is obligated to take its traditional role in providing the best possible treatment for patients who are in need of it, and psychotherapy is an inherent part of treatment.     

The role of medical physics in prostate cancer radiation therapy

Medical physics, both as a scientific discipline and clinical service, hugely contributed and still contributes to the advances in the radiotherapy of prostate cancer. The traditional translational role in developing and safely implementing new technology and methods for better optimizing, delivering and monitoring the treatment is rapidly expanding to include new fields such as quantitative morphological and functional imaging and the possibility of individually predicting outcome and toxicity. The pivotal position of medical physicists in treatment personalization probably represents the main challenge of current and next years and needs a gradual change of vision and training, without losing the traditional and fundamental role of physicists to guarantee a high quality of the treatment. The current focus issue is intended to cover traditional and new fields of investigation in prostate cancer radiation therapy with the aim to provide up-to-date reference material to medical physicists daily working to cure prostate cancer patients. The papers presented in this focus issue touch upon present and upcoming challenges that need to be met in order to further advance prostate cancer radiation therapy. We suggest that there is a smart future for medical physicists willing to perform research and innovate, while they continue to provide high-quality clinical service. However, physicists are increasingly expected to actively integrate their implicitly translational, flexible and high-level skills within multi-disciplinary teams including many clinical figures (first of all radiation oncologists) as well as scientists from other disciplines.     

Spatial distribution, biomass and population dynamics of Mysis relicta in Lake Michigan

The abundance, biomass, and life history traits of Mysis relicta were evaluated in the spring, summer, and autumn of 2000 at 8 nearshore (45 m) and 8 offshore (75–110 m) stations throughout central and southern Lake Michigan. Abundance was also evaluated on a smaller scale during June 2000 at 4 nearshore and 4 offshore stations in southeastern Lake Michigan. For large-scale sampling, the abundance of M. relicta did not differ among locations in the spring. In the summer and autumn the abundance of M. relicta was similar among offshore stations with the exception of one station each season; for nearshore stations, abundance was generally highest off Pentwater, Michigan. The abundance of mysids was not consistently high for central or southern basin sites, although overall biomass was higher in the southern basin each season. Abundance of Mysis was positively correlated with bottom depth, but not with bottom water temperature, surface water temperature, or mean chlorophyll concentration. Within the smaller region in southeast Lake Michigan, the abundance of M. relicta differed among locations for both nearshore and offshore stations. Brood size and size of reproductive females did not differ among lake wide locations, but the proportion of females with broods and the size distribution of M. relicta did.