细胞功能测定

Missing data frequently arise in the course of research studies. Understanding the mechanism that led to the missing data is important in order for investigators to be able to perform analyses that will lead to proper inference. This chapter will review different missing data mechanisms, in ...

In this chapter, we introduce the basics of Bayesian data analysis. The key ingredients to a Bayesian analysis are the likelihood function, which reflects information about the parameters contained in the data, and the prior distribution, which quantifies what is known about the paramete ...

This chapter introduces some fundamental results in survival analysis. We first describe what is censored failure time data and how to interpret the failure time distribution. Two nonparametric methods for estimating the survival curve, the life table estimator and the Kaplan-Meier e ...

The Medical Subject Headings (MeSH) thesaurus used by the National Library of Medicine defines logistic regression models as “statistical models which describe the relationship between a qualitative dependent variable (that is, one which can take only certain discrete values, su ...

When the same subjects or laboratory animals are observed across a set of different conditions or over time, we are usually interested in studying change. In these study designs, each subject serves as its own control. In this chapter, we consider different ways to assess change over time, for exampl ...

Hematopoietic stem cells (HSCs) have been studied for decades in order to understand their stem cell biology and their potential as treatments in gene therapy, and those studies have resulted in tremendous advancement of understanding HSCs. However, most of the studies required the sacri ...

Bacterial artificial chromosome (BAC) recombineering is a novel technique for DNA manipulation. It starts from an original chromosomal gene locus that is modified to introduce a transgene under the expression control of the original gene locus. In most cases a cell type specific promoter ...

Stable transgene insertion into a host genome irrevocably and unambiguously marks individual cells and all their descendants, i.e., the respective cell clone. Based thereon, retroviral gene marking has become an important tool for investigating the in vivo fate of different cell types, ...

This chapter describes the methods we use to transduce mouse and human hematopoietic stem cells (HSCs) and human embryonic stem cells (hESCs). We provide detailed protocols for producing high-titer lentiviral supernatants by transient transfection and for measuring viral titers. ...

The benzodiazepines are a large, commonly prescribed family of psychoactive drugs. We describe a method permitting the simultaneous detection and quantification of 12 benzodiazepines in serum using ultra-performance liquid chromatography (UPLC) coupled with tandem mass sp ...

Busulfan is a chemotherapy drug widely used as part of conditioning regimens for patients undergoing bone marrow transplantation (BMT). Challenges of busulfan treatment include a narrow therapeutic window and wide inter- and intra-patient variability. Inappropriately low dr ...

Nonketotic hyperglycinemia (NKH), a metabolic disorder due to defects in the glycine cleavage system, leads to the accumulation of toxic levels of glycine. Glycine levels in these patients may be lowered by sodium benzoate treatment. Benzoic acid binds to glycine to form hippurate, which is s ...

Marijuana, which is made from crushing the leaves, flowers, and sometimes the stems of the plant Cannabis sativa, contains more than 30 cannabinoids. The major psychoactive cannabinoid is delta-9-tetrahydrocannabinol (THC). The major metabolite of THC, 11-nor-delta 9-carboxy-tet ...

Cocaine is a widely abused stimulant. Numerous methods exist for the identification of the drug, or more commonly, one of its metabolites in urine. Urine testing is useful for most cases, but it is necessary to use other matrices in forensic situations and when subjects are anuric. We describe a novel me ...

Cocaine, a stimulant, is a commonly abused drug. Cocaine and its metabolites are measured in various biological specimens for clinical and forensic purposes. Urine or plasma or serum is spiked with deuterated internal standards cocaine-d3, benzoylecgonine-d3, ecgonine methyl este ...

The simultaneous determination and quantification of cocaine and its major metabolite, benzoylecgonine, in meconium using UPLC-MS/MS is described. Ultra-performance liquid chromatography (UPLC) is an emerging analytical technique which draws upon the principles of chro ...

Creatine metabolism disorders include a creatine transporter deficiency, as well as, deficiencies of two enzymes involved in creatine synthesis, arginine–glycine amidinotransferase (AGAT) and guanidinoacetate methyltransferase (GAMT). Laboratory diagnosis of th ...

A liquid–liquid extraction (LLE) of drugs and internal standard (promazine) is performed by mixing urine at basic pH with 1-chlorobutane. There are no hydrolysis or derivatization steps. After centrifugation the organic (upper) layer is transferred to another tube and evaporated. The d ...

Centrifuged urine, internal standard (promazine), and ammonium formate buffer are mixed in an autosampler vial to achieve a 10-fold dilution of the specimen. Without additional pretreatment, 10 �L of the sample is injected onto a C18 reverse phase column for gradient analysis with ammonium ...

Clinical laboratories around the world are recognizing the power of mass spectrometry. This technique, especially when coupled to gas chromatography or liquid chromatography, is revolutionizing the analysis of many analytes. Unlike many other techniques which measure one anal ...