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751.
为了空气消毒和预防呼吸道传染病,生产了中草药烟熏剂"寿而康空气消毒保健香"。经中国人民解放军第二军医大学等单位检测,杀灭空气中细菌有效率99.95%。急性经口毒性试验LD50>5000mg/kg,慢性毒理试验观察未发现中毒和蓄积中毒,属于实际无毒类。现场试验自然菌杀灭率90%以上,对预防呼吸道传染病流感、流脑等效果显著。 相似文献
752.
《Endocrine practice》2023,29(7):509-516
ObjectiveThe cardiovascular (CV) and renal benefits of sodium-glucose cotransporter-2 inhibitors (SGLT2i) in people with type 2 diabetes are well known. However, similar beneficial effects of SGLT2i in combination with dipeptidyl peptidase-4 inhibitors (DPP4i) are unknown. It is of interest to explore a trial-level meta-analysis to fill this knowledge gap.MethodsA literature search was conducted in the PubMed and Embase databases until January 31, 2023. All CV outcome trials (CVOTs) reporting the CV and renal outcomes of SGLT2i with or without background DPP4i therapy against the placebo were retrieved. A meta-analysis was subsequently conducted by applying the inverse variance-weighted averages of pooled logarithmic hazard ratio using primarily random-effects analysis.ResultsThis meta-analysis showed that the beneficial 3-point major adverse cardiovascular events composite (3 CVOTs; N = 32 418), the composite of CV death or heart failure hospitalization (hHF) (4 CVOTs; N = 37 687), hHF (3 CVOTs; N = 27 545), CV death (4 CVOTs; N = 34 565), and renal outcomes (2 CVOTs; N = 25 406) with SGLT2i were similar with or without background DPP4i therapy against the placebo (Pheterogeneity = .71, .07, .87, .72, and .25; respectively). However, against the placebo, the summary estimates for the 3-point major adverse cardiovascular events composite, hHF, and renal outcomes were stronger with SGLT2i alone, whereas the summary estimates for CV death or hHF composite were larger with SGLT2i with background DPP4i therapy.ConclusionBeneficial CV and renal effects of SGLT2i are similar against the placebo regardless of background DPP4i therapy. 相似文献
753.
754.
A benign-by-design method for the determination of boron (B) in microsamples of biological tissues was developed. This is
a simple, automated, microdigestion method. Use of reagents and generation of waste are minimized, and the use of toxic/hazardous
reagents is eliminated as compared to currently available B methodology. Microsamples are accommodated by the method; 100–400
mg sam ples were used in this study. B is determined by inductively coupled plasma atomic emission spectrometry (ICPAES) at
249.678 nm. The instrument detection limit for B is 0.01 Μg/mL. Interference studies have been investigated for 21 common
elements. Over 250 analyses of standard reference materials were analyzed during the study dura tion. Recoveries for a series
of biological tissues, both plant and ani mal, ranged from 82–104%. 相似文献
755.
【目的】了解红树林有害生物风险及其防控,维护红树林健康生长,发挥红树林的生态功能。【方法】2018—2019年,连续2年对广东省中山市红树林有害生物种类进行系统调查监测,并对薇甘菊和星天牛2种有害生物在中山市的分布状况、定殖和扩散的可能性、潜在危害性、受害对象的重要性、防控难度等进行分析,结合红树林的生态效益,参照国际有害生物风险性分析方法对两者在中山市红树林的危害风险性进行综合分析评估。【结果】调查发现,中山市红树林主要有害生物有23种,其中薇甘菊、星天牛最为严重,评估风险性R值分别为1.63和1.61,属中度危险的林业有害生物。【结论】薇甘菊和星天牛目前仅在中山市红树林局部地区发生危害,但具有明显扩散蔓延趋势,应该建立以应急除治、生物防治、生态修复等多种技术相结合的生态控制技术体系。 相似文献
756.
F.W. Jennings G.M. Urquhart P.K. Murray B.M. Miller 《International journal for parasitology》1980,10(1):27-32
Three nitroimidazole compounds were tested for trypanocidal activity against early (3-day) T. brucei TREU 667 infections. Compound 1 (1-methyl-2-carbamoyl-oxy-methyl-5-nitroimidazole) at both 5 and 20 mg/kg given as four daily doses was ineffective, while Compound 2 (3-(1-methyl-5-nitroimidazole-2-yl)-3α, 4,5,6,7, 7α-hexahydro-1, 2-benz-isoxazole) at 4 × 80 mg/kg and Compound 3 (3-(1-methyl-5-nitroimidazole-2-yl)-4, 5-hexamethylene-Δ2-isoxazoline) at 4 × 20 mg/kg both elicited a permanent cure. When tested against late (21-day) infections of T. brucei 667 neither Compound 2 nor Compound 3 given singly, or in various combinations was effective in that parasitaemias returned rapidly in nearly all mice.When the trypanocidal drug ‘Berenil’ was administered followed by the Compound 3, the majority of the mice with a 21-day infection of T. brucei TREU 667 or T. brucei LUMP 1001 were cured permanently. When ‘Berenil’ alone was used the mice usually relapsed within a few weeks of treatment. The isolate used affected the outcome of the treatment. Higher dosages of ‘Berenil’ followed by Compound 3 were required to cure infections with T. brucei LUMP 1001 than with T. brucei TREU 667.The importance of these findings in the treatment of human sleeping sickness with central nervous system involvement is discussed. 相似文献
757.
Abdullah Ali H. Alzahrani Raed A. Alharbi Mohammed Sarhan A. Alzahrani Mohammed A. Sindi Ghalia Shamlan Faisal A. Alzahrani Mohammad A. Albanghali Abdulmajeed Abdulghani A. Sindi 《Saudi Journal of Biological Sciences》2021,28(7):4016-4021
Vitamin D deficiency and periodontitis are commonly prevalent among Saudi adults. However, the association between periodontitis and vitamin D status has not been well documented. This study aims to examine the association between periodontitis and vitamin D status among adults in the Albaha region of Saudi Arabia. A case-control study of 123 Saudi adults was conducted; 60 had severe or moderate periodontitis, and 63 were periodontally healthy. Data was collected by an online self-reported sociodemographic questionnaire. All participants then underwent a full periodontal examination. Blood samples were also provided to assess participants’ vitamin D statuses through serum levels of 25-hydroxyvitamin D (25(OH)D). A total of 60 cases and 63 controls matched for BMI (30.2 ± 4.86 kg/m2), age (40.01 ± 7.73 years), and sex (46.3% and 53.7% male and female, respectively) participated in the study. Mean levels of 25(OH)D were significantly lower in periodontitis participants than in controls (25.03 ± 8.55 ng/ml, 29.19 ± 12.82 ng/ml, p = 0.037, respectively). Lower odds of periodontitis were detected per unit of 25(OH)D level (OR 0.964, 95% CI; 0.931–0.999, p = 0.043). In conclusion, periodontitis is significantly associated with deficient and insufficient levels of vitamin D among Saudi adults in the Albaha region. Future longitudinal research with a larger sample size may be suggested to confirm these results. 相似文献
758.
Melvin L. Myers 《人类与生态风险评估》2007,13(5):1042-1052
Methods for the identification, evaluation, and control of hazards are well recognized, whereas a method for the anticipation of hazards has eluded the field of industrial hygiene. The Emerging Technologies Team at the National Institute for Occupational Safety and Health has developed a method for anticipating not only occupational hazards but also potential benefits of emerging technologies for occupational safety and health. This method incorporates forecasting tools with a prospective assessment step into the risk assessment model, stresses research results as an iterative driver in the assessment, and depends on inherently safer design to eliminate or reduce hazards. An iterative process that involves the occupational safety and health professional as a team member in the development of emerging technologies is recommended. 相似文献
759.
760.
Prevention of biofilm formation by polymer modification 总被引:3,自引:0,他引:3
Bacterial biofilm formation on synthetic polymers plays an important role in industry and in modern medicine, leading, for example, to difficult-to-treat infections caused by colonized foreign bodies. Prevention of biofilm formation is a necessary step in the successful prophylaxis of such infections. One approach is to inhibit bacterial adherence by polymer surface modification. We have investigated polymer modification by glow discharge treatment in order to study the influence of the modified surface on bacterial adherence. Surface roughness, surface charge density and contact angles of the modified polymers were determined and related to the adherence ofStaphylococcus epidermidis KH6. Although no influence of surface roughness and charge density on bacterial adherence was noticed, a correlation between the free enthalpy of adhesion (estimated from contact angle measurements) and adherence was observed. There seems to exist a certain minimum bacterial adherence, independent of the nature of the polymer surface. Modified polymers with negative surface charge allow for bacterial adherence close to the adherence minimum. These polymers could be improved further by the ionic bonding of silver ions to the surface. Such antimicrobial polymers are able to prevent bacterial colonization, which is a prerequisite for biofilm formation. It is suggested that modification of polymers and subsequent surface coupling of antimicrobials might be an effective approach for the prevention of bacterial biofilm formation. 相似文献