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Results for “sensitivity analysis”

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PubMed2026

High-Sensitivity ctDNA Analysis Uncovers Relevant Signals Missed by NGS in Pancreatic Cancer.

PURPOSE: Pancreatic ductal adenocarcinoma (PDAC) carries high mortality despite multimodal therapy, and improved biomarkers are needed to guide perioperative care. This study evaluated the prognostic significance of Kirsten rat sarcoma virus (KRAS)-mutant circulating tumor DNA (ctDNA) detected by next-generation sequencing (NGS) and digital droplet PCR (ddPCR) in localized PDAC. EXPERIMENTAL DESIGN: In this prospective cohort study (2020-2024), patients with localized PDAC undergoing neoadjuvant chemotherapy (NAC) were enrolled across multiple sites within Northwestern Medicine. Blood samples for ctDNA were assessed at diagnosis, after NAC, and after resection using tumor-agnostic NGS and ddPCR targeting KRAS G12D/V/R mutations. Overall survival (OS) was assessed using Kaplan-Meier analysis. RESULTS: The cohort included 106 patients. At diagnosis, KRAS ctDNA was detected in 17.2% (17/99) by NGS and 64.9% (63/97) by ddPCR. Detection by both platforms was associated with shorter OS, with the higher-sensitivity ddPCR assay providing greater prognostic discrimination by identifying additional patients with poor outcomes not captured by NGS (NGS median OS 11.2 vs. 30.5 months, P < 0.001; ddPCR median OS 24.7 vs. 70.9 months, P = 0.004). Stratified by detection method, median OS was shortest in patients with ctDNA detected by both NGS and ddPCR (10.9 months), longest in those not detected by either platform (40.7 months), and intermediate in patients detected only by ddPCR (26.9 months; P < 0.001). CONCLUSIONS: In localized PDAC, KRAS-mutant ctDNA detected by NGS or ddPCR was associated with worse survival. ddPCR identified additional patients missed by NGS. Integrating ddPCR with NGS ctDNA measures may improve perioperative risk stratification, although validation is needed before clinical implementation.

Humans↗
PubMed2024

Causal effects of sedentary behaviours on the risk of migraine: A univariable and multivariable Mendelian randomization study.

BACKGROUND: Migraine is a common and burdensome neurological disorder. The causal relationship between sedentary behaviours (SBs) and migraine remains instinct. We aimed to evaluate the roles of SBs including watching TV, using computer and driving in the risk of migraine. METHODS: We conducted a univariable and multivariable Mendelian randomization (MR) study based on summary datasets of large genome-wide association studies. The inverse variance weighted method was utilized as the primary analytical tool. Cochran's Q, MR-Egger intercept test, MR pleiotropy residual sum and outlier and leave-one-out were conducted as sensitivity analysis. Additionally, we performed a meta-analysis to combine the causal estimates. RESULTS: In the discovery analysis, we identified causal associations between time spent watching TV and an increased risk of migraine (p&#x2009;=&#x2009;0.015) and migraine without aura (MO) (p&#x2009;=&#x2009;0.002). Such causalities with increasing risk of migraine (p&#x2009;=&#x2009;0.005), and MO (p&#x2009;=&#x2009;0.006) were further verified using summary datasets from another study in the replication analysis. There was no significant causal association found between time spent using computer, driving and migraine or its two subtypes. The meta-analysis and multivariable MR analysis also strongly supported the causal relationships between time spent watching TV and an increased risk of migraine (p&#x2009;=&#x2009;0.0003 and p&#x2009;=&#x2009;0.034), as well as MO (p&#x2009;<&#x2009;0.0001 and p&#x2009;=&#x2009;0.0004), respectively. These findings were robust under all sensitivity analysis. CONCLUSIONS: Our study suggested that time spent watching TV may be causally associated with an increased risk of migraine, particularly MO. Large-scale and well-designed cohort studies may be warranted for further validation. SIGNIFICANCE STATEMENT: This study represents the first attempt to investigate whether a causal relationship exists between SBs and migraine. Utilizing MR analysis helps mitigate reverse causation bias and confounding factors commonly encountered in observational cohorts, thereby enhancing the robustness of derived causal associations. Our MR analysis revealed that time spent watching TV may serve as a potential risk factor for migraine, particularly MO.

Humans↗
PubMed2026

Vestibular schwannoma associated normal pressure hydrocephalus: clinical features and shunt responsiveness compared with idiopathic NPH.

BACKGROUND: Vestibular schwannoma (VS) is commonly associated with obstructive hydrocephalus due to mass effect; however, a rarer communicating form resembling normal pressure hydrocephalus (NPH) has also been described, possibly related to impaired CSF absorption from elevated CSF protein. We aimed to characterize the clinical and imaging features of VS-associated NPH (VS-NPH) and compare them with those of an idiopathic NPH (iNPH) cohort. METHODS: We retrospectively analyzed 18 patients with VS-NPH identified between 2008 and 2024. For comparison, 41 iNPH patients were drawn from a prospective longitudinal study at our center. Variables included demographics, tumor size, VS treatment modality, CSF parameters, Radscale imaging features, and shunt responsiveness. RESULTS: VS-NPH patients had markedly higher CSF protein levels than patients with iNPH (median 100 vs. 51&#xa0;mg/dL, p&#xa0;<&#xa0;0.001). Radiological features largely overlapped; however, parasagittal sulcal narrowing was more frequent in VS-NPH (61&#xa0;% vs.13&#xa0;%, p&#xa0;=&#xa0;0.002). These differences remained significant in the sensitivity analysis excluding the two patients without gait impairment. VS-NPH patients were younger in the primary analysis (66.8 vs. 72.0&#xa0;years, p&#xa0;=&#xa0;0.03), while exploratory associations between larger tumor size and both earlier NPH symptom onset (r&#xa0;=&#xa0;-0.48, p&#xa0;=&#xa0;0.049) and smaller callosal angle (r&#xa0;=&#xa0;-0.49, p&#xa0;=&#xa0;0.048) attenuated to non-significant trends in the sensitivity analysis. Tumor size was&#xa0;<&#xa0;30&#xa0;mm in 89&#xa0;% of patients. Ventriculoperitoneal shunt (VPS) resulted in clinical improvement in both groups, although response rates were numerically lower in VS-NPH than in iNPH (63&#xa0;% vs.75&#xa0;%). CTT was positive in 9 of 11 VS-NPH patients who underwent testing, although improvement after shunting also occurred in patients with negative CTT results or without prior CTT. CONCLUSIONS: VS-NPH may represent a secondary subtype of NPH with distinct biochemical and subtle imaging features. Elevated CSF protein may contribute to altered CSF dynamics. These findings are exploratory and require confirmation in larger prospective studies.

Humans↗
PubMed2025

Efficacy of Janus kinase inhibitor combined with phototherapy in non-segmental vitiligo: systematic review and meta-analysis.

BACKGROUND: Vitiligo is a chronic autoimmune disease causing skin depigmentation and psychosocial issues. Non-segmental vitiligo often shows limited response to standard therapies. The IFN-&#x3b3;-JAK-STAT pathway plays a key role, and combining JAK inhibitors with NB-UVB may improve repigmentation. AIM: To evaluate the efficacy of JAK inhibitors (baricitinib or tofacitinib) plus NB-UVB versus NB-UVB without JAK inhibitors in adult NSV. METHODS: PubMed, Cochrane, and ClinicalTrials.gov were searched till August 2024 for randomized controlled trials. Four studies, comprising 217 adults (121 in the combination group and 96 in the control group), were analyzed using RevMan 5.4. Bias was assessed via Newcastle-Ottawa, Cochrane ROB-2, and ROBINS-I tools. RESULTS: Combination therapy significantly reduced total VASI compared to controls (MD = -4.96, 95% CI [-9.29, -0.63], p&#x2009;=&#x2009;0.02), with a greater effect on sensitivity analysis (MD = -6.84, p&#x2009;=&#x2009;0.0007). Significant reductions were seen in face/neck (MD = -0.17, p&#x2009;=&#x2009;0.002), trunk (MD = -3.62, p&#x2009;=&#x2009;0.0001); acral (MD = -0.85, p&#x2009;=&#x2009;0.0002) and extremity (MD = -4.61, p&#x2009;<&#x2009;0.00001) regions after sensitivity analysis. Patients were more likely to achieve &#x2265;50% (RR = 6.87, p&#x2009;<&#x2009;0.00001) and &#x2265;75% (RR = 15.13, p&#x2009;=&#x2009;0.006) repigmentation. CONCLUSIONS: JAK inhibitor plus NB-UVB markedly improves the repigmentation in adult NSV compared to NB-UVB alone.

Humans↗
PubMed2026

Distal versus proximal radial access for diagnostic cerebral angiography: comparative outcomes and learning curve analysis.

BACKGROUND AND PURPOSE: Distal transradial access (dTRA) is an alternative to proximal transradial access (pTRA) for neuroangiography, but comparative real-world data and evidence on its early learning curve remain limited. We compared procedural performance and access-site complications between dTRA and pTRA and evaluated the early learning curve of dTRA. METHODS: We retrospectively analyzed 470 diagnostic cerebral angiography procedures, representing 421 unique patients, performed via radial access at a single center between January 2025 and February 2026, including 237 dTRA and 233 pTRA procedures. Baseline characteristics, including age, sex, body mass index (BMI) category, aortic arch type, and antiplatelet/anticoagulant use, procedural performance, and clinically assessed access-site events were compared between groups. Radial artery occlusion (RAO) was assessed by postoperative bedside pulse examination and confirmed with Doppler ultrasound when clinical findings were uncertain. Multivariable logistic regression was used to evaluate predictors of RAO, persistent bleeding or repeated compression, hand edema, and a composite access-site event endpoint. Because repeated procedures occurred in a subset of patients and event counts were limited, first-procedure sensitivity analysis and analyses of infrequent outcomes were interpreted cautiously. The dTRA learning process was assessed in the first 100 dTRA cases performed by a single operator using multivariable regression, cumulative sum (CUSUM) analysis, segmented trend analysis, and phase-based comparisons. RESULTS: Baseline characteristics were comparable between groups, including age, male sex, BMI category, aortic arch type, and antiplatelet/anticoagulant use. Compared with pTRA, dTRA was associated with more puncture attempts (3.0 [2.0-4.0] vs 2.0 [1.0-3.0], P&#xa0;<&#xa0;0.001), longer puncture time (2.0 [1.0-5.0] vs 2.0 [1.0-3.0] min, P&#xa0;=&#xa0;0.003), lower first-pass success (19.4% vs 35.2%, P&#xa0;<&#xa0;0.001), and a higher crossover rate (11.4% vs 6.0%, P&#xa0;=&#xa0;0.037). However, dTRA was associated with a lower clinically assessed RAO rate (2.5% vs 7.7%, P&#xa0;=&#xa0;0.011). On multivariable analysis, pTRA was independently associated with higher odds of RAO (OR 3.27, 95% CI 1.26-8.49, P&#xa0;=&#xa0;0.015) and the composite access-site event endpoint (OR 3.12, 95% CI 1.55-6.28, P&#xa0;=&#xa0;0.001). Similar findings were observed in a sensitivity analysis restricted to the first procedure per patient. In the first 100 dTRA cases, cumulative dTRA experience was independently associated with shorter total procedure time (beta&#xa0;=&#xa0;-0.074&#xa0;min/case, P&#xa0;=&#xa0;0.009), while CUSUM and moving-average analyses suggested that the major learning effect occurred within approximately the first 10-15 cases. CONCLUSIONS: In this retrospective single-operator cohort, dTRA was associated with lower clinically assessed RAO than pTRA despite greater access difficulty. The early learning effect was mainly reflected in shorter total procedure time. These findings support the feasibility of dTRA but should be interpreted cautiously given the study's observational design and limited anatomical data.

Humans↗
PubMed2024

Uric Acid Levels and Cardiovascular and Cerebrovascular Diseases: A Mendelian Randomization Study.

INTRODUCTION: The relationship between uric acid (UA) levels and cardiovascular and cerebrovascular diseases (CCVD) is controversial. A two-sample Mendelian randomization (MR) study was conducted to explore the causal effects of UA levels on CCVD. METHODS: Genetic variants strongly associated with UA levels were selected as instrumental variables from the Genome-Wide Association Study (GWAS) dataset. The GWAS data, sourced from the Global Urate Genetics Consortium (GUGC), comprised a sample size of 110,347 individuals. The selected CCVD outcomes included stroke, coronary artery disease (CAD), as well as atrial fibrillation and flutter. The primary analytical approach employed the inverse-variance weighted (IVW) method, supplemented by MR-Egger and weighted median as complementary methods. Sensitivity analysis was performed to test heterogeneity and pleiotropy. RESULTS: The MR analysis results indicated a causal association between UA levels and stroke (odds ratio [OR]: 1.002; 95% confidence interval [CI]: 1.000-1.003; p = 0.036), CAD (OR: 1.118; 95% CI: 1.044-1.197; p = 0.001), as well as atrial fibrillation and flutter (OR: 1.141; 95% CI: 1.037-1.256; p = 0.007). The results of MR-Egger and weighted median methods confirmed the direction of the IVW results, enhancing the robustness of the findings. No significant anomalies were detected in the sensitivity analysis. CONCLUSION: The MR study suggests that UA levels exert causal effects on stroke, CAD, as well as atrial fibrillation and flutter.

Humans↗
PubMed2026

Prevalence of homologous recombination repair genes alterations in metastatic castration-resistant prostate cancer, a multicentric study.

INTRODUCTION: Homologous Recombination Repair (HRR) genes alterations are a resistance mechanism to therapies by taxanes or Androgen Receptor Signalling inhibitors in Metastatic Castration Resistant Prostate Cancer (mCRPC). BRCA-mutated mCRPC patients are eligible to poly adenosine diphosphateribose polymerase inhibitors (PARPi). Therefore, assessing the population-specific prevalence of HRR-related genes alterations is of public healthcare importance. METHODS: This retrospective, non-interventional, multicentric study was conducted across 6 reference French centers in a "real-life" setting. 788 paraffin-embedded mCRPC patient-samples were included and submitted to testing for BRCA1/2 in six different centers; additionally, non-BRCA HRR-related genes were investigated in two different centers. RESULTS: Among the samples, n=602 (76.4%) were contributive for molecular testing. In multivariate analysis by logistic regression and sensitivity analysis, only sample age (P<0.01), sample surface area (P=0.02) and institution (P=0.018) remained statistically significant. BRCA alterations were detected in n=39/602 (6.5%) of contributive samples, with n=35 and n=4 alterations of BRCA2 and BRCA1 respectively. Non-BRCA HRR-related genes alterations were detected in n=12/157 (7.6%) of contributive samples, with alterations of mainly ATM (n=6, 3.8%), CDK12 (n=4, 2.5%) and CHEK2 (n=2, 1.3%). DISCUSSION: In this study, testing contributivity was similar or higher that of other studies in the literature, and observed mutations prevalences were similar to that of other screenings of western populations. Harmonising per-centres protocols and enhancing molecular testing contributivity with the screening of circulating DNA samples and expanding its range by including non-BRCA HRR-related genes in all reference centres will enable more patients to be accurately treated by targeted therapies. LEVEL OF EVIDENCE: 3 (grade C).

Male↗
PubMed2025

Plasma metabolites mediate the causal relationship between gut microbiota and erectile dysfunction: insights from Mendelian randomization study.

BACKGROUND: While the relationship between gut microbiota and erectile dysfunction (ED) has been reported, the specific pathways involved remain unclear. AIM: This study aims to investigate the causal relationship between gut microbiota and ED, and to identify the potential role of plasma metabolites as mediators. METHODS: Utilizing aggregated genome-wide association study (GWAS) data, a comprehensive two-sample Mendelian randomization (MR) analysis was performed involving 196 gut microbiota taxa, 1400 plasma metabolites and ED. Causal relationships between gut microbiota, plasma metabolites and ED were explored. In addition, mediation analysis was applied to identify the pathway from gut microbiota to ED mediated by plasma metabolites. OUTCOMES: This study reveals that plasma metabolites act as mediators regulating the influence of gut microbiota on ED. RESULTS: MR analysis identified causal relationships between six gut microbial taxa and ED, with Butyrivibrio increasing the risk of ED, while Alistipes, Prevotella 9, Dialister, Marvinbryantia, and LachnospiraceaeUCG010 exhibited protective effects. Additionally, 45 plasma metabolites demonstrated causal associations with ED. Finally, mediation analysis revealed four mediation relationships. Sensitivity analysis indicated no heterogeneity or pleiotropy in this study. CLINICAL IMPLICATIONS: Modulating gut microbiota or targeting specific metabolites may offer new therapeutic approaches for ED, highlighting the potential for microbiome-based interventions. STRENGTHS AND LIMITATIONS: The MR approach and large-scale GWAS data provide robust causal evidence, but the findings are limited by their focus on European populations and lack of experimental validation. Further studies are needed to confirm these mechanisms in diverse cohorts and functional models. CONCLUSION: This study establishes a causal link between gut microbiota, plasma metabolites, and ED, identifying specific microbial taxa and metabolites as key contributors to ED risk. The mediating role of plasma metabolites highlights potential therapeutic strategies, such as probiotics or dietary interventions targeting harmful metabolites.

Mendelian randomization↗
PubMed2026

Integrated transcriptome analysis and machine learning to construct a homeostatic model of acetylation for bladder cancer and validate the key gene CES1.

BACKGROUND: Bladder cancer (BLCA) is one of the most common malignant tumors of the urinary system. Protein acetylation (PA) plays a critical role in regulating multiple biological processes (BPs), cellular homeostasis, and cancer-related signaling pathways. This study aimed to construct a homeostatic model of acetylation for BLCA using integrated transcriptome analysis and machine learning and to validate the key gene CES1. METHODS: RNA sequencing (RNA-seq) and clinical data were obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Acetylation-related differentially expressed genes (DEGs) in BLCA were screened using differential expression analysis (DEA). An acetylation homeostatic model was constructed via univariate, machine learning-based least absolute shrinkage and selection operator (LASSO) and multivariate Cox regression analyses, followed by validation in multiple cohorts. Single-cell RNA-seq analysis was used to explore gene expression patterns in diverse cell types. Enrichment analysis (EA), immune infiltration, and drug sensitivity analysis (DSA) were performed to characterize molecular features of different risk groups. Finally, the biological function of CES1 as the key gene was verified by in vitro knockdown experiments. RESULTS: We established a robust acetylation homeostatic model consisting of five genes, which effectively predicted overall survival (OS) and served as an independent prognostic factor in BLCA. High-risk patients showed significantly poorer prognosis, distinct immune infiltration profiles, and differential drug sensitivity. CES1 was identified and validated as the key gene in this model, which was highly expressed in BLCA and associated with poor prognosis. Knockdown of CES1 markedly suppressed cell proliferation, invasion, and migration, and reduced intracellular coenzyme A (CoA) levels, thereby regulating PA homeostasis. CONCLUSIONS: We developed and validated a novel acetylation homeostatic model for survival stratification and personalized treatment guidance in BLCA, based on integrated transcriptome analysis and machine learning. CES1 is closely associated with intracellular CoA levels and the malignant progression of BLCA. Its potential association with PA homeostasis requires further mechanistic validation, and it may act as a candidate therapeutic biomarker for BLCA.

Bladder cancer (BLCA)↗
PubMed2025

Causal relationship between educational attainment and the occurrence of venous thromboembolism.

BACKGROUND: The association between educational attainment (EA) and arterial thrombotic disease has been reported, but the causal relationship between EA and venous thromboembolism (VTE) is not clear. We aimed to assess the causal effect of EA on VTE using the two-sample mendelian randomization (MR) method. METHODS: Data mining was conducted on the genome wide association studies (GWAS), with exposure factor EA and outcome factor VTE. Two-sample Mendelian Randomization (TSMR) analysis was conducted, with the results obtained from the random effects inverse variance weighted method (IVW). Use the MR-Egger method for pleiotropy analysis and leave one method for sensitivity analysis to verify the reliability of the data. RESULTS: Genetically predicted decreased EA was associated with a decreased risk of VTE in both the FinnGen consortium and UK Biobank (FinnGen-VTE: OR&#x2009;=&#x2009;0.848; 95% CI 0.776-0.927; P&#x2009;=&#x2009;2.84&#x2009;&#xd7;&#x2009;10-4; UKB-VTE OR&#x2009;=&#x2009;0.996; 95% CI 0.994-0.999; P&#x2009;=&#x2009;0.008) under a multiplicative random-effects IVW model. Results were consistent in all sensitivity analyses and no horizontal pleiotropy was detected. CONCLUSIONS: The MR technique instructed a potential inverse causative relationship between EA and occurrence of VTE. Therefore, patients with low EA should be more vigilant about the occurrence of VTE.

Venous Thromboembolism↗
PubMed1976

Sensitive fluorometric method for tissue tocopherol analysis.

A sensitive, highly reproducible method for tissue tocopherol analysis that combines saponification in the presence of large nmount of ascorbic acid to remove interfering substances, extraction fo the nonsponifiable lipids with hexane, and fluorometric measurement of the tocopherol is presented. The nonsaponifiable lipids phase contained only one fluorochrome in the 290 am excitation and 330 nm emission range, and it was identified as tocopherol by thin layer and column chromatography. Column chromatography of the hexane extract of a saponified, 14C-tocopherolspiked microsomal fraction showed that no measurable oxidation to tocopherylquinone had occurred. The flurometric method for tocopherol analysis was applied to homogenates and subcellular fractions from rat liver, kidney, lung, and heart and red blood cells. The heavy mitochondrial and microsomal fractions had the highest subcellular concentrations of tocopherol.

Animals↗
PubMed2025

Exploring the causal association between television viewing and meniscal injuries: A two-sample Mendelian randomization analysis.

The aim of this study was to assess whether there is a potential causal relationship between sedentary behavior and meniscal injuries based on the Mendelian randomization (MR) method. This study used a two-sample MR design to integrate pooled data from a large-scale genome-wide association studies (GWAS). Single nucleotide polymorphisms (SNPs) that were significantly associated with sedentary behavior (represented by daily TV-viewing time) and independent of each other were selected as instrumental variables, while focusing on data from populations of European ancestry. To ensure the robustness and reliability of the analyses, 3 mainstream MR analysis methods were combined in this study: inverse variance weighted (IVW), weighted median estimation (WME) and MR-Egger regression. Heterogeneity test, horizontal multivariate analysis, and leave-one-out sensitivity test were also conducted to further validate the stability of causal estimation. The results of the IVW method showed that sedentary behavior was significantly associated with the risk of meniscus injury, with an OR (95% CI) of 2.93 (1.89-4.52), and a P-value of&#x2005;<&#x2005;.001, suggesting that sedentary behavior may be an important risk factor for meniscus injury. No significant bias was found in the heterogeneity test and the assessment of multiple validity, and the sensitivity analysis showed that the effect of individual SNPs on the overall estimation was small, and the results had good robustness. This study provides genetic epidemiological evidence of a positive causal effect of sedentary behavior on meniscal injuries based on a causal inference approach with genetic instrumental variables. The results suggest that reducing sedentary time, especially prolonged TV watching behavior, may reduce the risk of meniscus injury to some extent.

Humans↗
PubMed1979

Evaluation of emergency ambulance characteristics under several criteria.

A methodology and analysis are presented for evaluating response time characteristics of emergency ambulance systems. The methodology is based on a Monte Carlo simulation technique and a heuristic optimal-seeking technique for locating emergency ambulances under several criteria based on response time distribution. Optimization criteria include minimum mean system response time, minimum system fractile response time and minimum level-loaded response time. The evaluation methodology is applied to the metropolitan area of Los Angeles County. Ambulance response characteristics and loads are discussed in detail. From these results alternative dispatch polices can be evaluated. Complementing the analysis is a presentation of a sensitivity analysis and an analysis of existing ambulance sites. Unique to the methodology is the adaption of the heuristic optimal-seeking technique to include any of the three criteria and the effectiveness of the methodology for analyzing small or large ambulance systems.

Ambulances↗
PubMed1976

Simplified low-pressure high-resolution nucleotide analyser.

A simple nucleotide analyser was constructed from commercially available components. A 20 cm X 0.4 cm I.D. column of pellicular anion exchanger operating at approximately 20 p.s.i. was found to perform identically with published methods using high-pressure equipment. The eluant was monitored using a variable-wavelength UV monitor. A very simple device for producing variable gradients was employed. The nucleotide analyser was trouble free to operate and the results were both linear and reproducible. Applications to the rapid analysis of nucleotides and the high-sensitivity analysis (approx. 10 pmoles) of cyclic 3',5'-adenosine monophosphate and cyclic 2',3'-guanosine monophosphate and tissue nucleotides are described.

Anion Exchange Resins↗