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1.
Zhonghua Yi Xue Za Zhi ; 104(14): 1184-1187, 2024 Apr 09.
Artigo em Chinês | MEDLINE | ID: mdl-38583051

RESUMO

The clinical data of 23 patients undergoing real-time echocardiography-guided infusion port implantation in the Breast Center of Tsinghua Changgung Hospital in Beijing from January to July 2021 were analyzed. The length of catheter insertion L1 was initially estimated using surface measurement method in all patients. Intraoperatively, transthoracic echocardiography was applied using the parasternal four-chamber view to visualize the catheter image within the right atrium, and the length of catheter insertion L2 was recorded under the guidance of echocardiography. Postoperatively, chest radiographs were taken in the upright position to observe the position of the catheter tip. According to chest CT scans, the ideal length (L) for catheter tip placement was calculated when it was located at the junction of superior vena cava and right atrium. Bland-Altman scatter plot analysis and linear regression fitting test were used on L1 and L2 respectively with L to evaluate the consistency. A total of 23 patients were included in this study, among which one case of left breast cancer patient undergoing breast-conserving surgery had difficulty in identifying the catheter tip position due to residual pleural effusion obscuring the imaging of the cardiac apex four-chamber view. In 22 patients, the results of intraoperative ultrasound imaging were good, including 1 case of catheter ectopic to azygos vein, and 21 cases of right atrial catheter could be detected by ultrasound. Statistical analysis showed that there was a good consistency between L1 and L, L2 and L, and the difference between them was d=0.28 cm (95%CI:-1.76-2.31 cm) and d=0.20 cm(95%CI:-0.84-1.23 cm), respectively, with no statistical significance (P>0.05). In the linear regression model, L2 and L had a higher fit than L1, and the difference was statistically significant (R²=0.954, P<0.001). This study found that real-time echocardiographic localization technique can be applied in adult port surgery to replace X-ray-guided real-time catheter tip detection and adjustment to the optimal position.


Assuntos
Cateterismo Venoso Central , Cateteres Venosos Centrais , Adulto , Humanos , Cateteres de Demora , Ecocardiografia/métodos , Veia Cava Superior/diagnóstico por imagem , Feminino
3.
Genet Mol Res ; 15(4)2016 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-27808392

RESUMO

The retracted article is: Cao L-H, Zhao P-L, Liu Z-M, Sun S-C, et al. (2015). Efficacy and safety of nucleoside analogues in preventing vertical transmission of the hepatitis B virus from father to infant. Genet. Mol. Res. 14: 15539-15546. The article published in Genetics and Molecular Research 14 (4): 15539-15546 (2015) is a very good paper, but it appears that the authors' group submitted this manuscript to multiple journals, which is ethical misconduct. This manuscript (similar language and identical data) was published in the Experimental and Therapeutic Medicine Journal prior to being submitted to GMR. There are parts copied from "Efficacy and safety of nucleoside analogs on blocking father-to-infant vertical transmission of hepatitis B virus", by Li-Hau Cao, Pei-Li Zhao, Zhi-Min Liu, Shao-Chun Sun, et al. Exp. Ther. Med. 9 (6): 2251-2256 (2015) - DOI: 10.3892/etm.2015.2379. The GMR editorial staff was alerted and after a thorough investigation, there is strong reason to believe that the peer review process was failure. Also, after review and contacting the authors, the editors of Genetics and Molecular Research decided to retract this article in accordance with the recommendations of the Committee on Publication Ethics (COPE). The authors and their institutions were advised of this serious breach of ethics.

4.
Genet Mol Res ; 14(4): 15539-46, 2015 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-26634520

RESUMO

We examined the efficacy and safety of nucleoside analogues in preventing the vertical transmission of hepatitis B virus (HBV) from father to infant. We included 201 patients who visited the liver clinic of our hospital. The patients were positive for HBV surface antigen (HBsAg), HBeAg, anti-HBc, and HBV DNA; 189 patients (94%) had abnormal liver function. In all couples, the fathers were HBV DNA-negative and had normal liver function, and the mothers were anti-HB-positive before pregnancy. The control group comprised 188 couples who visited our hospital during the same time period. The fathers in the control group were positive for HBsAg, HBeAg, anti-HBc, and HBV DNA. The mothers were HBsAg-negative and anti-HBs-positive. No infants in the case group were HBsAg-positive and HBV DNA-positive, and all were anti-HBs-positive, indicating that father to infant HBV vertical transmission was prevented in the case group. In the control group, 147 of 188 newborns (78.2%) were anti-HBs-positive at birth, 28 (14.9%) were HBV DNA-positive, and 19 (10.1%) were HBsAg-positive. A significant difference was observed between the two groups. No statistically significant difference was observed in the gestational age, birth weight, birth length, 1-min and 8-min Apgar score, jaundice, other internal and surgical diseases, delivery mode, and other birth information between the neonates born to couples in the case and control groups; there were no fetal malformations and stillbirths in the two groups. Our results showed that administration of antiretroviral therapy to HBV DNA-positive fathers before pregnancy can cause a decrease in the viral load and prevent father to infant HBV vertical transmission. The use of antiviral nucleoside analogues before pregnancy was safe in fathers, and the fathers who wanted children could continue to use anti-viral therapy. The sample size in our study was small, and further studies with a large sample size and longer follow-up time are required for determining the use of nucleoside analogues from the point view of prenatal and postnatal care.


Assuntos
Antivirais/uso terapêutico , Pai , Vírus da Hepatite B , Hepatite B/tratamento farmacológico , Hepatite B/transmissão , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Adulto , Antivirais/efeitos adversos , Biomarcadores , Estudos de Casos e Controles , Feminino , Hepatite B/diagnóstico , Hepatite B/virologia , Vírus da Hepatite B/genética , Humanos , Lactente , Recém-Nascido , Masculino , Gravidez , Complicações na Gravidez , Fatores de Risco
5.
Genet Mol Res ; 14(2): 4651-7, 2015 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-25966239

RESUMO

The aim of this study was to examine the efficacy of combined immunization of hepatitis B immunoglobulin (HBIG) and hepatitis B vaccine (HBVac) in blocking father-infant transmission of hepatitis B virus (HBV). Newborns positive at birth for blood HBV sur-face antigen (HBsAg) and/or HBV DNA were selected and immunized with HBIG combination HBVac. At 7 months, HBV markers and HBV DNA of each neonate were measured using electrochemiluminescence with the Cobas-e-411 Automatic Electrochemiluminescence Immuno-assay Analyzer and fluorescence quantitative polymerase chain reaction. Among all 7-month-old subjects, the negative conversion rates of HBV DNA and HBsAg were 48/61 (78.7%) and 19/41 (46.3%), respectively. Therefore, this study demonstrated that prompt combination injection of HBIG and HBVac can protect some of the HBV DNA- and/ or HBsAg-positive newborns from HBV.


Assuntos
Pai , Vacinas contra Hepatite B/administração & dosagem , Vírus da Hepatite B/imunologia , Hepatite B/prevenção & controle , Imunoglobulinas/administração & dosagem , Feminino , Hepatite B/transmissão , Humanos , Recém-Nascido , Masculino
6.
Scand J Rheumatol ; 31(4): 230-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12369656

RESUMO

OBJECTIVE: To evaluate the efficacy and tolerability of rofecoxib 25 mg and 50 mg once daily versus placebo and naproxen 500 mg twice daily in patients with RA. METHODS: Eligible patients were randomized (double-blind) to placebo (n = 289), rofecoxib 25 mg (n = 306), 50 mg (n = 286) once daily, or naproxen (n = 142) for 12 weeks. Efficacy assessments included the ACR core set, with prespecified primary endpoints: patient and investigator global assessments of disease activity, tender and swollen joint counts. Investigator-reported adverse experiences, routine laboratory and vital sign measurements were monitored. RESULTS: Rofecoxib 25 mg, 50 mg, and naproxen provided similar treatment effects, significantly different from placebo, consistent with improvement, for all primary endpoints. Effects were evident at the earliest assessment (week 2) and sustained for 12 weeks. All treatments were generally well-tolerated. CONCLUSIONS: Rofecoxib 25 mg once daily had similar efficacy to naproxen 500 mg twice daily (a standard dose). No additional benefit was seen with 50 mg rofecoxib.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Inibidores de Ciclo-Oxigenase/administração & dosagem , Lactonas/administração & dosagem , Adulto , Idoso , Artrite Reumatoide/fisiopatologia , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Isoenzimas/antagonistas & inibidores , Articulações/fisiopatologia , Lactonas/efeitos adversos , Masculino , Proteínas de Membrana , Pessoa de Meia-Idade , Naproxeno/administração & dosagem , Placebos , Prostaglandina-Endoperóxido Sintases , Sulfonas , Resultado do Tratamento
7.
MedGenMed ; 3(4): 6, 2001 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-11965201

RESUMO

CONTEXT: Patients treated with nonselective cyclooxygenase inhibitors (nonsteroidal anti-inflammatory drugs [NSAIDs]) often experience dyspepsia and upper gastrointestinal (GI) adverse effects, and frequently require GI comedications and diagnostic procedures. OBJECTIVE: This study combined existing data to test the hypothesis that GI comedications and GI diagnostic procedures occur less frequently in osteoarthritis (OA) patients treated with rofecoxib compared with nonselective NSAIDs. DESIGN: Combined analysis of 8 randomized controlled clinical trials. SETTING: Rheumatology and general practice clinics. PATIENTS: Men and women aged 40 years and older with OA. INTERVENTIONS: Random assignment to placebo (n = 514), rofecoxib (n = 3357; 12.5, 25, or 50 mg daily combined; average 24.7 mg), or NSAIDs (n = 1564; ibuprofen 800 mg thrice daily, diclofenac 50 mg thrice daily, or nabumetone 1500 mg daily, combined). MAIN OUTCOME MEASURES: The cumulative incidence of patients using GI comedications (antacids, antispasmodics, antiflatulents, antiregurgitants, H2 antagonists, proton pump inhibitors, sucralfate, prostaglandins, other antiulcer therapy) and needing GI procedures (upper GI barium studies, upper or lower GI endoscopies) over 12 months. RESULTS: Compared with those treated with NSAIDs, patients treated with rofecoxib had a significantly lower incidence of GI comedication use (17.5% vs 27.0%, P <.001) and GI procedures (3.3% vs 5.3%, P =.02) over 12 months. Similar results were seen in analyses of protocols with placebo; in these studies, rates of GI comedications and procedures were highest with NSAIDs, while those with rofecoxib and placebo were similar to each other. CONCLUSIONS: OA patients treated with rofecoxib for up to 12 months required significantly less GI comedication and significantly fewer GI procedures than those treated with NSAIDs.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Inibidores de Ciclo-Oxigenase/uso terapêutico , Gastroenteropatias/induzido quimicamente , Gastroenteropatias/tratamento farmacológico , Lactonas/uso terapêutico , Osteoartrite/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/efeitos adversos , Butanonas/administração & dosagem , Butanonas/efeitos adversos , Butanonas/uso terapêutico , Ensaios Clínicos como Assunto , Inibidores de Ciclo-Oxigenase/administração & dosagem , Inibidores de Ciclo-Oxigenase/efeitos adversos , Diclofenaco/administração & dosagem , Diclofenaco/efeitos adversos , Diclofenaco/uso terapêutico , Método Duplo-Cego , Esquema de Medicação , Quimioterapia Combinada , Feminino , Gastroenteropatias/diagnóstico , Humanos , Ibuprofeno/administração & dosagem , Ibuprofeno/efeitos adversos , Ibuprofeno/uso terapêutico , Lactonas/administração & dosagem , Lactonas/efeitos adversos , Masculino , Pessoa de Meia-Idade , Nabumetona , Ensaios Clínicos Controlados Aleatórios como Assunto , Sulfonas
8.
Arch Intern Med ; 160(19): 2998-3003, 2000 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-11041909

RESUMO

BACKGROUND: Most nonsteroidal anti-inflammatory drugs (NSAIDs) are nonselective cyclooxygenase (COX-1 and COX-2) inhibitors and are associated with a variety of upper gastrointestinal (GI) tract symptoms. The roles of COX-1 and COX-2 in the pathogenesis of these symptoms are unclear. To test whether COX-2 inhibition with rofecoxib would have greater GI tolerability than nonselective COX-1 and COX-2 inhibition, we compared the incidences of (1) treatment discontinuations for GI adverse events (AEs) and (2) prespecified dyspeptic-type GI AEs among patients with osteoarthritis treated with rofecoxib vs NSAIDs. METHODS: A prespecified, combined analysis of investigator-reported GI AEs in all 8 double-blind, randomized, phase 2b/3 osteoarthritis trials of rofecoxib was conducted. Patients included men and women with osteoarthritis (N = 5435); there was no upper age limit for entry. Treatments tested included rofecoxib, 12.5, 25, or 50 mg (combined), vs ibuprofen, diclofenac, or nabumetone (combined). Primary outcomes were the time (by survival analysis) to (1) treatment discontinuation due to GI AEs and (2) first reported dyspeptic-type GI AE. Between-treatment comparisons were made by log-rank test. RESULTS: The number of treatment discontinuations caused by GI AEs during 12 months was significantly lower (P=.02) with rofecoxib vs NSAIDs (8.2 vs 12.0 per 100 patient-years; relative risk, 0.70; 95% confidence interval, 0.52-0.94). The incidence of prespecified dyspeptic-type GI AEs during the first 6 months was significantly lower (P=.02) with rofecoxib vs NSAIDs (69.3 vs 85.2 per 100 patient-years; relative risk, 0.85; 95% confidence interval, 0.74-0.97). However, the difference between treatments in dyspeptic-type GI AEs was attenuated after 6 months. CONCLUSION: Rofecoxib was associated with a lower incidence of treatment discontinuations due to GI AEs over 12 months and a lower incidence of dyspeptic-type GI AEs over 6 months than treatment with nonselective COX inhibitors, or NSAIDs. Arch Intern Med. 2000;160:2998-3003


Assuntos
Inibidores de Ciclo-Oxigenase/efeitos adversos , Dispepsia/induzido quimicamente , Lactonas/efeitos adversos , Osteoartrite/tratamento farmacológico , Prostaglandina-Endoperóxido Sintases/metabolismo , Dor Abdominal/induzido quimicamente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios não Esteroides/uso terapêutico , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Feminino , Humanos , Isoenzimas/antagonistas & inibidores , Masculino , Proteínas de Membrana , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Sulfonas
9.
J Bone Miner Res ; 15(7): 1275-85, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10893676

RESUMO

L-type calcium channels have been identified previously in both osteoblast-like osteosarcoma cell lines and primary cultures of osteoblasts using numerous techniques such as patch clamp recording, drug inhibited 45Ca2+ uptake, and Fura-2 measurements, but intact bone has not been investigated. Using reverse-transcription polymerase chain reaction (RT-PCR) we found that the three major isoforms of the alpha 1-subunit of L-type calcium channels, (alpha 1C, alpha 1D, and alpha 1S) are present in RNA extracted from ROS 17/2.8 osteosarcoma cells, rat femur, and rat skull. Sequencing of most of the alpha 1C-subunit from rat femur and ROS cells revealed that the splice variants in osteosarcoma cells and intact bone differ, but there are no unique sequence variations compared with those found in other tissues. Northern blot analysis of ROS cell RNA indicated that cyclic adenosine monophosphate (cAMP), but not 1 alpha, 25-dihydroxyvitamin D3, increased the messenger RNA (mRNA) of the alpha 1C-subunit. Western blot of ROS cell lysates revealed a band of more then 220 kDa, the amount of which increased in cells treated with cAMP. Using confocal microscopy combined with immunohistochemistry in ROS cells, intact bone, and cartilage, we found that the alpha 1C-subunit of this channel is expressed in osteoblasts and chondrocytes suggesting this channel may be a pathway for signal transduction in intact tissue, because it is in osteosarcoma cell lines and primary osteoblasts grown in tissue culture.


Assuntos
Osso e Ossos/metabolismo , Canais de Cálcio Tipo L/genética , AMP Cíclico/farmacologia , Miocárdio/metabolismo , Biossíntese de Proteínas , Transcrição Gênica , Animais , Calcitriol/farmacologia , Cálcio/metabolismo , Cartilagem/metabolismo , Células Cultivadas , Fêmur/metabolismo , Osteoblastos/metabolismo , Osteossarcoma , Biossíntese de Proteínas/efeitos dos fármacos , Isoformas de Proteínas/genética , Subunidades Proteicas , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Crânio/metabolismo , Transcrição Gênica/efeitos dos fármacos , Células Tumorais Cultivadas
10.
Hunan Yi Ke Da Xue Xue Bao ; 25(1): 23-6, 2000 Feb 28.
Artigo em Chinês | MEDLINE | ID: mdl-12212238

RESUMO

Small loading and strengthening exercises were performed by 22 athletes(11 males and 11 females). The levels of serum hormones and their urinary metabolites were detected. The results showed that the serum levels of testosterone(T), free testosterone(FT) and 17-OH-progesterone(17-OHP) in male athletes exhibited no conspicuous changes. The excretion of their urinary androsteroids was significantly increased after exercises(P < 0.05), but significantly decreased in the recovery period(P < 0.05). After small loading exercises, their serum levels of T and FT revealed no obvious changes except those of 17-OHP which evidently increased in female athletes(P < 0.05); whereas the excretion of their urinary steroid hormones declined promptly after the exercises and in the recovery period (all P < 0.05). After strengthening exercises, the serum levels of T, FT and 17-OHP decreased distinctly in female athletes (all P < 0.05), the excretion of their urinary steroid hormones raised clearly after training and in the recovery period(P < 0.05). Therefore, it is suggested that the secretion and metabolism of sex hormones in the organism are influenced by the loading quality of sports during training, and sexual difference exists simultaneously.


Assuntos
17-alfa-Hidroxiprogesterona/sangue , Esportes/fisiologia , Testosterona/sangue , 17-alfa-Hidroxiprogesterona/urina , Adolescente , Adulto , Exercício Físico/fisiologia , Feminino , Humanos , Masculino , Fatores Sexuais , Testosterona/urina , Suporte de Carga
11.
JAMA ; 282(20): 1929-33, 1999 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-10580458

RESUMO

CONTEXT: Nonsteroidal anti-inflammatory drug (NSAID)-induced gastrointestinal (GI) toxic effects, such as upper GI tract perforations, symptomatic gastroduodenal ulcers, and upper GI tract bleeding (PUBs), are thought to be attributable to cyclooxygenase 1 (COX-1) inhibition. Rofecoxib specifically inhibits COX-2 and has demonstrated a low potential for causing upper GI injury. OBJECTIVE: To compare the incidence of PUBs in patients with osteoarthritis treated with rofecoxib vs NSAIDs. DESIGN: Prespecified analysis of all 8 double-blind, randomized phase 2b/3 rofecoxib osteoarthritis trials conducted from December 1996 through March 1998, including one 6-week dose-ranging study, two 6-week efficacy studies vs ibuprofen and placebo, two 1-year efficacy studies vs diclofenac, two 6-month endoscopy studies vs ibuprofen and placebo, and one 6-week efficacy study vs nabumetone and placebo. SETTING: Multinational sites. Participants Osteoarthritis patients (N = 5435; mean age, 63 years [range, 38-94 years]; 72.9% women). INTERVENTIONS: Rofecoxib, 12.5, 25, or 50 mg/d (n = 1209, 1603, and 545, respectively, combined) vs ibuprofen, 800 mg 3 times per day (n = 847), diclofenac, 50 mg 3 times per day (n = 590); or nabumetone, 1500 mg/d (n = 127) (combined). MAIN OUTCOME MEASURE: Cumulative incidence of PUBs for rofecoxib vs NSAIDs, based on survival analysis of time to first PUB diagnosis, using PUBs that met pre-specified criteria judged by a blinded, external adjudication committee. RESULTS: The incidence of PUBs over 12 months was significantly lower with rofecoxib vs NSAIDs (12-month cumulative incidence, 1.3% vs 1.8%; P = .046; rate per 100 patient-years, 1.33 vs 2.60; relative risk, 0.51; 95% confidence interval, 0.26-1.00). The cumulative incidence of dyspeptic GI adverse experiences was also lower with rofecoxib vs NSAIDS over 6 months (23.5% vs 25.5%; P = .02), after which the incidence rates converged. CONCLUSION: In a combined analysis of 8 trials of patients with osteoarthritis, treatment with rofecoxib was associated with a significantly lower incidence of PUBs than treatment with NSAIDs.


Assuntos
Analgésicos não Narcóticos/efeitos adversos , Anti-Inflamatórios não Esteroides/efeitos adversos , Inibidores de Ciclo-Oxigenase/efeitos adversos , Hemorragia Gastrointestinal/induzido quimicamente , Lactonas/efeitos adversos , Úlcera Péptica/induzido quimicamente , Adulto , Idoso , Analgésicos não Narcóticos/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Butanonas/efeitos adversos , Butanonas/uso terapêutico , Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase/uso terapêutico , Diclofenaco/efeitos adversos , Diclofenaco/uso terapêutico , Feminino , Hemorragia Gastrointestinal/diagnóstico , Humanos , Ibuprofeno/efeitos adversos , Ibuprofeno/uso terapêutico , Isoenzimas , Lactonas/uso terapêutico , Masculino , Proteínas de Membrana , Pessoa de Meia-Idade , Nabumetona , Osteoartrite/tratamento farmacológico , Úlcera Péptica/diagnóstico , Modelos de Riscos Proporcionais , Prostaglandina-Endoperóxido Sintases , Ensaios Clínicos Controlados Aleatórios como Assunto , Sulfonas
12.
Stat Med ; 16(17): 1913-23, 1997 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-9304763

RESUMO

Estimation of sample size in clinical trials requires knowledge of parameters that involve the treatment effect and variability, which are usually uncertain to medical researchers. The recent release within the European Union of a Note for Guidance from the Commission for Proprietary Medical Products (CPMP) highlights the importance of this issue. Most previous papers considered the case of continuous response variables that assume a normal distribution; some regarded the portion up to the interim stage as an 'internal pilot study' and required unblinding. In this paper, our concern is with the case of binary response variables, which is more difficult than the normal case since the mean and variance are not distinct parameters. We offer a design with a simple stratification strategy that enables us to verify and update the assumption of the response rates given initially in the protocol. The design provides a method to re-estimate the sample size based on interim data while preserving the trial's blinding. An illustrative numerical example and simulation results show slight effect on the type I error rate and the decision making characteristics on sample size adjustment.


Assuntos
Ensaios Clínicos como Assunto/estatística & dados numéricos , Projetos de Pesquisa , Tamanho da Amostra , Humanos , Modelos Estatísticos , Distribuição Aleatória
14.
Proc Natl Acad Sci U S A ; 92(22): 10212-6, 1995 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-11607586

RESUMO

Combinatorial chemistry is gaining wide appeal as a technique for generating molecular diversity. Among the many combinatorial protocols, the split/recombine method is quite popular and particularly efficient at generating large libraries of compounds. In this process, polymer beads are equally divided into a series of pools and each pool is treated with a unique fragment; then the beads are recombined, mixed to uniformity, and redivided equally into a new series of pools for the subsequent couplings. The deviation from the ideal equimolar distribution of the final products is assessed by a special overall relative error, which is shown to be related to the Pearson statistic. Although the split/recombine sampling scheme is quite different from those used in analysis of categorical data, the Pearson statistic is shown to still follow a chi2 distribution. This result allows us to derive the required number of beads such that, with 99% confidence, the overall relative error is controlled to be less than a pregiven tolerable limit L1. In this paper, we also discuss another criterion, which determines the required number of beads so that, with 99% confidence, all individual relative errors are controlled to be less than a pregiven tolerable limit L2 (0 < L2 < 1).

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