The study showed that the L-argmine-adsorbing capacity of strong-acidic resin 001?7 was 1.135 meq per ml of wet resin by controlling the flow rate of the broth at 1/52 vvm, and the efficiency of the elution was higher by using ammnia water as an eluent at the flow rate of 1/50 vvm. About 160 ml of the above eluant was decolorized with 10 ml of 201?4 resin, the transparance of the decolorized eluant was over 90%, and no adsorption of L-arginine by the 201?4 resin was observed. Under the controlled conditions, the extraction yield of L-arginine reached over 95%.

Objective To investigate the correlation between vertebral artery tortuosity and posterior circulation ischemia (PCI). Methods The patients with PCI aged ≥50 years old and the controls without PCI at the same time were enrolled. CT angiography was performed in all patients. The cervical vertebral artery tortuosity was observed and rated, and the related risk factors for influencing PCI were analyzed. Results A total of 112 patients with PCI and 90 controls were enrolled. Univariate analysis showed that the proportions of patients with hypertension (80. 36% vs. 54. 44% ; χ2 = 15. 613, P < 0. 001), smoking (35. 71% vs. 18. 89% ; χ2 = 6. 974, P = 0. 008), alcohol consumption (25. 89% vs. 10. 00% ; χ2 = 8. 253, P = 0. 004), posterior circulation vascular stenosis (54. 46% vs. 24. 44% ; χ2 = 18. 578, P < 0. 001), and vertebral artery tortuosity (71. 43% vs. 48. 89% ; χ2 = 10. 695, P = 0. 001), as well as the levels of the total cholesterol (4. 96 ± 1. 26 mmol/L vs. 4. 61 ± 1. 04 mmol/L; t = - 2. 110, P = 0. 036 ), low-density lipoprotein cholesterol (3. 02 ± 0. 90 mmol/L vs. 2. 69 ± 0. 78 mmol/L; t = - 2. 671, P = 0. 008 ), and fibrinogen (3. 67 ± 1. 69 mg/L vs. 3. 25 ± 0. 97 mg/L; t = - 2. 002, P = 0. 047) in the PCI group were significantly higher than those in the control group. The proportion of bilateral vertebral artery tortuosity in the PCI group was significantly higher that in the control group (30. 36% vs. 12. 22% ; χ2 = 9. 478, P =0. 002). The proportion of grade 3 vertebral artery tortuosity in the PCI group was significantly higher than that in the control group (43. 75% vs. 26. 67% ; χ2 = 6. 310, P = 0. 012). Multivariate logistic regression analysis showed that smoking (odds ratio [OR] 2. 339, 95% confidence interval [CI] 1. 037-5. 278; P =0. 041), low-density lipoprotein cholesterol (OR 1. 580,95% CI 1. 050-2. 377; P = 0. 028), hypertension (OR 2. 631, 95% CI 1. 237-5. 596; P = 0. 012), posterior circulation vascular stenosis (OR 3. 419, 95% CI 1. 638-7. 134; P = 0. 001), and vertebral artery tortuosity (OR 2. 413, 95% CI 1. 212-4. 803; P = 0. 012) were the independent risk factors for PCI. Conclusion The vertebral artery tortuosity is an independent risk factor for PCI in the middle-aged and elderly people.

Objective To investigate the predictive value of peripheral blood neutrophil-to-lymphocyte ratio (NLR) for stroke-associated pneumonia (SAP) in patients with acute stroke.Methods Consecutive patients with acute stroke were enrolled.Their clinical data were collected.The peripheral blood white blood cells,neutrophil and lymphocyte counts were detected within 24 h after admission,and the NLR was calculated.Multivariate logistic regression analysis was used to determine the independent correlation between NLR and SAP.The receiver operating characteristic (ROC) curve was used to analyze the predictive value of NLR for SAP.Results A total of 126 patients with acute stroke were enrolled,including 45 females (35.7％) and 81 males (64.3％).Their mean age was 64.8 years.Fifty-two patients (41.3％) had intracerebral hemorrhage,and 74 (58.7％) had ischemic stroke.Thirty-nine patients (31.0％) occurred SAP,and 87 (69.0％) did not occur SAP.Univariate analysis showed that age,National Institutes of Health Stroke Scale scores,fasting glucose,total white blood cell count,neutrophil count,NLR,and proportions of patients with hyperlipidemia,ischemic heart disease,atrial fibrillation,smoking,dysphagia,using acid suppressing drugs and indwelling gastric tube in the SAP group were significantly higher than those in the non-SAP group (all P ＜0.05),and the high-density lipoprotein cholesterol level and lymphocyte count in the SAP group were significantly lower than those in the non-SAP group (all P ＜ 0.05).Multivariate logistic regression analysis showed that NLR (odds ratio 2.079,95％ confidence interval 1.174-3.194;P =0.001) was an independent risk factor for SAP after adjustment for confounding factors.ROC curve analysis showed that when the NLR cutoff value was 6.765,the sensitivity of predicting SAP was 64.1％,the specificity was 73.6％,and the area under ROC curve was 0.721 (95％ confidence interval 0.630-0.813).Conclusions The elevated NLR in peripheral blood within 24 h after admission may has a certain predictive value for SAP in patients with acute stroke.