RP-HPLC法测定紫杉醇在大鼠血浆中的含量

目的建立紫杉醇在大鼠血浆中的定量分析方法,为药物动力学研究提供分析方法。方法采用RP-HPLC法。Li Chrospher 100反相C18色谱柱(250 mm×4.6 mm,5μm),乙腈-水(体积比50∶50)为流动相,流速为1.0 mL.min-1,紫外检测波长为227 nm,血浆样品经乙酸乙酯萃取,以内标法定量。结果线性范围为0.025~100.0 mg.L-1(r=1.0,n=5),日内RSD小于5%,日间RSD小于10%,定量限25μg.L-1。在以7.5 mg.kg-1的剂量静脉注射紫杉醇到大鼠身上后,药物很快分布到体内(t1/2α=0.16 h),并且快速的消除,消除半衰期仅有1.65 h,药物的平均保留时间tMR为0.52 h。结论所用方法简便、准确、专属性好,能够满足药物动力学研究的需要。     

Stimulation Hierarchy: Optimal Sequence for Double and Triple Extrastimuli During Electrophysiological Studies

To determine the optimal ventricular stimulation sequence, an 11-step programmed electrical stimulation (PES) protocol was completed, even if a ventricular arrhythmia (VA) was induced with earlier steps. The protocol consisted of one, two, and three extrastimuli during sinus rhythm (SR), and at two drive pacing rates (VP1 and VP2) plus rapid burst and ramp pacing. By analyzing the 79 completed protocols that induced the clinical arrhythmia, the following were determined: (1) the frequency of induced clinical and nonclinical VA with each stimulation step; (2) the yield ratio (YR) of each step, defined as the probability of inducing clinical versus nonclinical arrhythmia; (3) the cumulative yield of induced clinical and nonclinical arrhythmia with two widely used stimulation sequences, i.e., triple extrastimuli delivered early in the stimulation protocol (MMC sequence) and triple extrastimuli delayed until after double extrastimuli failed to induce the clinical arrhythmia (B sequence); (4) the relative efficiency of these sequences were determined. The percentage of induced clinical and nonclinical arrhythmia with SR + 3 extrastimuli, VP1 + 2 extrastimuli, and VP2 + 2 extrastimuli were (53%, 5%), (36%, 5%), and (41%, 9%), respectively. The cumulative yield of induced clinical VA with the MMC-type sequence reached 55% by the third step of the protocol, whereas 50% was attained only at the eighth step of the B-type sequence. The cumulative percentage of induced nonclinical VA with either sequence was similar during the early steps of the protocol. The MMC sequence was more efficient, requiring overall 36% of potential steps for clinical arrhythmia induction, compared with 48% for the B sequence (P less than 0.001). For questionable arrhythmia states, e.g., syncope of unknown origin and nonsustained VT, a modified sequence is proposed that may further reduce the induction of uninterpretable arrhythmias.     

Impact of childhood cancer on religious life of Korean families

This paper reports on the social and personal relevance of religious faith entering into the situation of family stress due to the illness of a child with cancer. The expectations of religious faith may include, objectively, the actual physical healing of the child or the determination of the child's fate; it may include, subjectively, the hope for emotional support, the provision of moral guidance in time of difficulty, or an overarching life-view. There were major religious changes in 20% of the families. While all the major religious faiths in South Korea were represented in the study, 61% of the sample identified Christianity as their primary religious response.     

Retrograde ejaculation: a systematic approach to non-invasive recovery of spermatozoa from post-ejaculatory urine for artificial insemination

Summary. Retrograde ejaculation is an uncommon but treatable form of male infertility. Successful recovery of live spermatozoa from the post-ejaculatory urine for artificial insemination is dependent on careful regulation of pH and osmolarity of the urine into which ejaculation takes place, and separation of the motile spermatozoa from the debris and cells which are found in these samples. Three pregnancies established by artificial insemination of spermatozoa recovered by non-invasive means from the bladders of men suffering from retrograde ejaculation are described. The techniques for preparing the urine for spermatozoal survival, and for removal of cells and debris by sedimentation or buoyant density centrifugation are discussed.     

Synthesis of 3-(3-pyridyl)- and 3-(3-benzo[b]thienyl)-D-alanine

The DL-arylamino acid ethyl ester derivatives of β-(3-pyridyl)-DL-alanine, and β-(3-benzo[b]thienyl)-DL-alanine were synthesized by diethyl acetamidomalonate condensation with the respective arylmethyl halides followed by partial hydrolysis to the monoethyl ester and decarboxylation. Each derivative was enzymatically resolved to a separable mixture of the corresponding N-acetyl-L-amino acid and the unchanged D amino acid derivative. Acidic hydrolysis of the latter gave the corresponding D-amino acid, the optical purity of which was established by HPLC analysis of the 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl isothiocyanate (GITC) derivative. The free D amino acids were converted to D-BOC derivatives by reaction with di-tert-butyldicarbonate in tert-butyl alcohol, water and sodium hydroxide.     

The histology of autologous auricular cartilage implanted into the nasal septum

This study attempts to evaluate the use of auricular cartilage for the treatment of nasal septal defects. A defect was made in the nasal septal cartilage in five rabbits and auricular cartilage grafted into the defect. The cartilage was microscopically examined 4 weeks later. The implanted cartilage was completely covered by ciliated columnar epithelium with minimal scar formation. Proliferation of the implanted cartilage and scattered ossification were observed. Seventeen patients with a nasal septal defect were treated by auricular cartilage implantation from April 1987 to through June 1992. Fiften patients (88%) had relief of symptoms and showed complete closure of the defect with a follow-up period of 2 years. The results of this study suggest that auricular cartilage may be of value in the repair of a nasal septal defect.