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1.
A column-switching, reversed-phase high-performance liquid chromatographic (HPLC) assay for a new structurally unique carbapenem antibiotic, ertapenem, in urine has been improved for selectivity and automated using a Packard MultiPROBE II EX pipetting station. The method uses column-switching for on-line extraction of the urine sample. The extraction column, analytical column, mobile phase, and timing of the column-switching valve have been changed to enhance selectivity for the analyte over endogenous background material. Sample transfer and dilution prior to direct-injection into the HPLC system have been accomplished using a Packard MultiPROBE II EX robotic liquid handling system.  相似文献   

2.
Inappropriate sample handling of blood, serum or plasma collected for the determination of hormone concentration may lead to inaccurate endocrine data and diagnoses. Many useful studies have been conducted to determine the potential effects of sample handling on measured hormone concentration. Unfortunately, because reported results frequently differ according to assay method, species studied and parameters measured, it is not always possible to predict the effect of specific sample handling scenarios as they are presented in practice. The objective of this review is to provide a summary of what has been reported in the literature regarding sample-handling procedures that may affect the measurement of hormone concentration in plasma or sera from animals being evaluated for reproductive function.  相似文献   

3.
城市生态系统研究中遥感技术的应用   总被引:2,自引:0,他引:2  
本文提出并论证了城市生态系统研究与遥感的总体方案及主要研究方向和研究方法。可以认为,用遥感技术作为获取数据的手段,用动态大系统理论分析数据,并借助于专家系统和地理信息系统处理和管理数据,可以解决城市生态系统研究中全方位信息的收集和巨大信息量的处理两大难题;通过引入中间变量把非空间直接可测变量表述为空间直接可测量的函数,从而在专家系统和地理信息系统的支持下扩大遥感技术的应用领域。  相似文献   

4.
目的利用胞内代谢物量的差异达到预测大肠埃希氏菌的药物敏感性结果。方法收集临床分离大肠埃希菌120株,在头孢他啶存在条件下培养4 h。收集菌体,测定细胞内化合物然后进行多变量分析。结果 120株大肠埃希菌的聚类分析结果很好地体现了药物敏感性特征,57株耐药菌中,有5株被误判,准确率为91%;47株中敏菌株中,有8株被误判,准确率为83%;16株敏感菌中有2株被误判;准确率为88%。结论该方法能够有效预测菌株的药敏结果,而且快速可靠。  相似文献   

5.
The increasing number of channels offered by new Microelectrode Array (MEA) systems raises the problem of data handling and analysis in real time. The goal of the RETINE project is to develop a new MEA system, called NeuroPXI, offering 256 channels with online features for MEA data recording, processing and stimulation. This system is a complete redesign of the ASIC-based BioMEA system developed previously. NeuroPXI is based on a front-end device featuring integrated electronics handling signal amplification and current-mode stimulation, and a back-end device handling real-time data processing and 2D spatiotemporal stimulus generation. Initial tests of this system have been performed on mouse spinal cord networks in which waves of activity were successfully recorded. Further tests of NeuroPXI, performed on rats, will consist first, in recording activity waves in the newborn retina and second, in patterned retinal stimulation combined with optical cortical recordings of the primary visual cortex. Such experiments have recently been conducted using the BioMEA system with standard pulse stimuli, and will be repeated with the NeuroPXI system to include more complex 2D-pattern stimuli.  相似文献   

6.
The combinatorial chemistry industry has made major advances in the handling and mixing of small volumes, and in the development of robust liquid-handling systems. In addition, developments have been made in the area of material handling for the high-throughput drug screening and combinatorial chemistry fields. Lastly, improvements in beamline optics at synchrotron sources have enabled the use of flash-frozen micron-sized (10-50 microm) crystals. The combination of these and other recent advances will make high-throughput protein crystallography possible. Further advances in high-throughput methods of protein crystallography will require application of the above developments and the accumulation of success/failure data in a more systematic manner. Major changes in crystallography technology will emerge based on the data collected by first-generation high-throughput systems.  相似文献   

7.
1. The functional response of predators describes the rate at which a predator consumes prey and is an important determinant of community dynamics. Despite the importance, most empirical studies have considered a limited number of models of functional response. In addition, the models often make strong assumptions about the pattern of predation processes, even though functional responses can potentially exhibit a wide variety of patterns. 2. In addition to the limited model consideration, model selections of functional response models cannot tease apart the components of predation (i.e. capture rate and handling time) when flexible traits are considered because it is always possible that many different combinations of the capture rate and handling time can lead to the same predation rate. 3. This study directly examined the capture rate and handling time of functional response in a mite community. To avoid the model selection problem, the searching and handling behaviour data were collected. The model selection was applied directly to these two components of predation data. Commonly used functional response models and models that allow for more flexible patterns were compared. 4. The results indicated that assumptions of the commonly used models were not supported by the data, and a flexible model was selected as the best model. These results suggest the need to consider a wider variety of predation patterns when characterizing a functional response. Without making a strong assumption (e.g. static handling time), model selections on functional response models cannot be used to make reliable inferences on the predation mechanisms.  相似文献   

8.
Free ranging reindeer (Rangifer tarandus tarandus) are driven into corral systems and handled each summer on the Seward Peninsula (Alaska, USA). During June and July of 1995-96 reindeer calves were inspected for injury, handled, weighed, and randomly treated with long-acting oxytetracycline. Calves that returned to subsequent handlings within the same year, received treatment only if they had been treated during their first handling. The effects of prophylactic antibiotic treatment and other factors, including weight, handling related injury, and sex on post-handling survival in reindeer calves were evaluated. Return rates of yearlings in 1996 and 1997 were analyzed using logistic regression. Weight change of calves between handlings was examined using a general linear model. Calf weight and handling injury were the only factors that significantly affected calf survival. No factor had a significant effect on calf weight change between handlings. Apparently, long-acting oxytetracycline was not an effective prophylactic treatment for this capture operation. The benefits of prophylactic antibiotic treatment have not been quantified and further studies of the effects and efficacy of prophylactic treatments are recommended. Ineffective treatments should be avoided because they may add additional stress to the captured animal. Managers should evaluate the potential effectiveness of a prophylactic treatment before indiscriminately applying one. Preventing calf injuries was the most effective method of reducing post-handling mortality in this study and should be given a high priority in the design of capture operations.  相似文献   

9.
Goal, Scope and Background  Performing a life cycle assessment (LCA) has been a rather resource and time-consuming business. The method of data collection may be problematic, and the quality of the final results can be influenced by the reliability of the data. Therefore, it is helpful to utilize an on-line data gathering system to save time and to improve the reliability of the collected raw data. Main Features  We have developed an LCA software package for a steel company. The software consists of two major parts: an LCA tool kit and an interface program. The LCA tool kit is a user interface for handling an LCA database server. It has powerful functions to execute systematic analysis, not only for the amount of energy and raw materials, but also for the volume of pollutants generated by each component. The latter is an interface program between a data handling system and an on-line data gathering system. This interface program is linked with three enterprise database systems, such as enterprise resource planning (ERP), an environmental management system (EMS) and an energy server system (ESS). In this study, we compared three different ways of performing LCA. Two of them are on-line methods, and another is manual. Results and Discussion  Among the three methods, the best method was on-line LCA linked with ERP, EMS and ESS. Case studies in steel works have shown that the current method is superior to manual data gathering in terms of time and cost (man-month) savings, data reliability and other applications. Results of life cycle inventory and life cycle impact assessment for steel products have shown monthly fluctuations due to fuel usage ratio, which have not been detected before using manual data gathering. Conclusions  An LCA can be performed quickly, if one is to employ the on-line data gathering system we have developed. The system consists of an LCA software package including the interface program and LCA tool kit, and the enterprise database systems. Case studies for LCA with the on-line system have shown superior performance to that carried out using the manual data entry method. Recommendations and Perspective  This system enables an enterprise to take Type III and conduct benchmarking to other companies or societies within a short time. Also, combining this tool with an environmental performance evaluation or accounting system can allow one to achieve a more progressive environmental management.  相似文献   

10.
Polyketides have diverse biological activities, including pharmacological functions such as antibiotic, antitumor and agrochemical properties. They are biosynthesized from short carboxylic acid precursors by polyketide synthases (PKSs). As natural polyketide products include many clinically important drugs and the volume of data on polyketides is rapidly increasing, the development of a database system to manage polyketide data is essential. MapsiDB is an integrated web database formulated to contain data on type I polyketides and their PKSs, including domain and module composition and related genome information. Data on polyketides were collected from journals and online resources and processed with analysis programs. Web interfaces were utilized to construct and to access this database, allowing polyketide researchers to add their data to this database and to use it easily. MapsiDB is available at .  相似文献   

11.
重症监护病房革兰阴性杆菌耐药性分析   总被引:1,自引:0,他引:1  
目的了解深圳市人民医院重症监护病房(ICU)革兰阴性杆菌的分布及其耐药性,指导临床合理用药。方法收集来自重症监护病房各类标本分离的革兰阴性杆菌540株,用VITEK AMS-60或VITEK-Ⅱ全自动微生物分析仪进行菌种鉴定,用K-B法进行药敏试验。结果ICU检出的革兰阴性杆菌以鲍曼不动杆菌、大肠埃希菌、铜绿假单胞菌和肺炎克雷伯菌为主,ESBLs阳性的大肠埃希菌和肺炎克雷伯菌比例为61.6%和51.8%,各类细菌对常用抗菌药物表现为严重耐药和多重耐药。结论该院ICU检出的革兰阴性杆菌以鲍曼不动杆菌、大肠埃希菌、铜绿假单胞菌和肺炎克雷伯菌为主,且呈现多重耐药性。  相似文献   

12.
Corticosteroids were measured in blood samples collected from 10 hens in two series with a time interval of nine days. In the first series blood was collected by venipuncture (wing vein), in the second by cardiac puncture. In each series, sampling took place immediately before (control), and 5 min as well as 18 h after intentional rough handling. Only samples obtained by cardiac puncture 5 min after rough handling showed markedly elevated hormone levels. Corticosteroids were also measured in blood collected from two other groups of hens, each including 10 birds. Samples were taken at 0 (control), 1, 5 and 40 min, one group being sampled by venipuncture, the other by cardiac puncture, None of the groups were subjected to rough handling. The hormone levels in samples obtained were significantly higher (P < 0.005) than the levels in the corresponding samples obtained by venipuncture.  相似文献   

13.
Multi-welled microtitre plates provide a convenient means of handling 'large block' multifactorial experiments with microbial cultures. An inexpensive instrument, termed a 'Biophotometer', has been designed to monitor microbial growth in each well, by transmitted light measurements. Optional microcomputer control is employed to facilitate scanning of plates and data handling. A unique method for agitating cultures is incorporated into the system. Typical results are presented to illustrate the versatility of this system.  相似文献   

14.
The BioImage database is a new scientific database for multidimensional microscopic images of biological specimens, which is available through the World Wide Web (WWW). The development of this database has followed an iterative approach, in which requirements and functionality have been revised and extended. The complexity and innovative use of the data meant that technical and biological expertise has been crucial in the initial design of the data model. A controlled vocabulary was introduced to ensure data consistency. Pointers are used to reference information stored in other databases. The data model was built using InfoModeler as a database design tool. The database management system is the Informix Dynamic Server with Universal Data Option. This object-relational system allows the handling of complex data using features such as collection types, inheritance, and user-defined data types. Informix datablades are used to provide additional functionality: the Web Integration Option enables WWW access to the database; the Video Foundation Blade provides functionality for video handling.  相似文献   

15.
《Biomarkers》2013,18(8):677-683
Sample handling and storage conditions in specimens frozen over long periods of time can severely impact marker levels. If laboratory technologies, practices and related protocols change over time, biomarker studies are potentially biased and report erroneous results. These issues and pitfalls are often overlooked in system biology studies using previously collected and stored materials, and are likely to be one notable cause for biomarker candidates failing to be validated. We present results from simulation studies quantifying the loss in statistical power to detect true biomarkers, due to diminishing concentration of analytes in samples subject to poor handling and storage conditions.  相似文献   

16.
Multi-welled microtitre plates provide a convenient means of handling 'large block' multifactorial experiments with microbial cultures. An inexpensive instrument, termed a 'Biophotometer', has been designed to monitor microbial growth in each well, by transmitted light measurements. Optional microcomputer control is employed to facilitate scanning of plates and data handling. A unique method for agitating cultures is incorporated into the system. Typical results are presented to illustrate the versatility of this system.  相似文献   

17.
The provision of effective emergency telemedicine and home monitoring solutions are the major fields of interest discussed in this study. Ambulances, Rural Health Centers (RHC) or other remote health location such as Ships navigating in wide seas are common examples of possible emergency sites, while critical care telemetry and telemedicine home follow-ups are important issues of telemonitoring. In order to support the above different growing application fields we created a combined real-time and store and forward facility that consists of a base unit and a telemedicine (mobile) unit. This integrated system: can be used when handling emergency cases in ambulances, RHC or ships by using a mobile telemedicine unit at the emergency site and a base unit at the hospital-expert's site, enhances intensive health care provision by giving a mobile base unit to the ICU doctor while the telemedicine unit remains at the ICU patient site and enables home telemonitoring, by installing the telemedicine unit at the patient's home while the base unit remains at the physician's office or hospital. The system allows the transmission of vital biosignals (3–12 lead ECG, SPO2, NIBP, IBP, Temp) and still images of the patient. The transmission is performed through GSM mobile telecommunication network, through satellite links (where GSM is not available) or through Plain Old Telephony Systems (POTS) where available. Using this device a specialist doctor can telematically "move" to the patient's site and instruct unspecialized personnel when handling an emergency or telemonitoring case. Due to the need of storing and archiving of all data interchanged during the telemedicine sessions, we have equipped the consultation site with a multimedia database able to store and manage the data collected by the system. The performance of the system has been technically tested over several telecommunication means; in addition the system has been clinically validated in three different countries using a standardized medical protocol.  相似文献   

18.

Infant handling (holding or carrying) by adult males is rare in mammals; however, high levels have been reported in some primates. Though infant handling is a costly behaviour, there are many benefits that male handlers can accrue. Infant handling by males is most conspicuous in platyrrhines and tends to be uncommon in catarrhines. In the latter species, research on male–infant interactions has focused on low-cost behaviours, such as proximity and grooming. However, to better understand the evolution of infant handling by males, more data on its occurrence across the Primate order are essential, even in species where it is relatively uncommon. We compare the occurrence of infant handling by males in three closely related species of catarrhine: Colobus vellerosus, C. guereza, and C. angolensis ruwenzorii. We collected focal animal samples on infants to quantify infant handling rates and durations, and found that adult male C. a. ruwenzorii handled infants much more frequently and for much longer than males in the other two species. We discuss how C. a. ruwenzorii’s unique social organization may explain high levels of infant handling by adult males in this species. More long-term and detailed comparisons of infant handling across species and populations will shed light on how sociality has shaped the evolution of this behaviour in the Primate order.

  相似文献   

19.
Abstract. Correspondence Analysis of species by environmental variables matrices is a relatively simple method for handling matrices which include many species and variables. If columns represent species and rows represent the states in which the environmental variables have been divided, each element of the matrix shows the number of releves in which the simultaneous occurrence of that species and that environmental variable state have been recorded. In this paper the use of the method for presence-absence data is considered. The method is appropriate for studies whose main purpose is to look for broad correlations between groups of environmental variables and groups of species. It is particularly useful for handling heterogeneous data sets including rare species and species-poor releves, a situation in which Correspondence Analysis and Canonical Correspondence Analysis are frequently complicated by the production of axes explaining the relationship between rare species and species-poor releves. Examples are presented with artificial data as well as with real data collected in the Mexican portion of the Chihuahuan Desert (Bolsón de Mapimi). It is shown for the Mapimi data that the method is robust to the partition of variables into different numbers of states.  相似文献   

20.
We describe a package of DNA data handling and analysis programs designed for microcomputers. The package is convenient for immediate use by persons with little or no computer experience, and has been optimized by trial in our group for a year. By typing a single command, the user enters a system which asks questions or gives instructions in English. The system will enter, alter, and manage sequence files or a restriction enzyme library. It generates the reverse complement, translates, calculates codon usage, finds restriction sites, finds homologies with various degrees of mismatch, and graphs amino acid composition or base frequencies. A number of options for data handling and printing can be used to produce figures for publication. The package will be available in ANSI Standard FORTRAN for use with virtually any FORTRAN compiler.  相似文献   

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