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11.
基于化学指纹图谱-生物热活性图谱关联检测的注射用双黄连冻干粉针质量控制方法的初步研究 总被引:2,自引:0,他引:2
为了建立包括生物热活性检测在内的中药注射剂质量控制方法, 本文以注射用双黄连冻干粉针为模式药, 建立HPLC-ELSD特征图谱, 进行相似度评价; 采用微量量热法, 建立生物热活性图谱, 并提取相关生物热动力学参数 (达峰时间 T2m , Tj和抑制率I%), 以相关系数法进行相似度评价。结果表明, HPLC-ELSD特征图谱不易区分不同贮藏条件下样品之间的微小差异, 特别是对生物污染样品基本无法辨识; 生物热活性图谱可以区别高温处理样品及污染变质样品, 并可以全面反映模型生物的热生物学信息, 提供了专属性较强的二维信息, 可作为化学特征图谱的有益补充。本文从质量均一性出发, 通过HPLC-ELSD特征图谱和生物热活性图谱关联检测对注射用双黄连冻干粉针进行质量控制, 为实现对中药注射剂质量变化的早期快速筛查, 预警其不良反应提供了技术参考。 相似文献
12.
Ti-6Al-4V profiles prepared by hot extrusion are usually accompanied by bending and twisting. The hot twist-stretch straightening is an effective strategy such that the bending deflection and twisting angle can be simultaneously decreased by a single straightening process. In addition, utilizing stress relaxation effect, the residual stress and springback can be greatly reduced by holding the straightening temperature and strain constant for a period after twist-stretch straightening. In this study, the hot deformation behaviors of the Ti-6Al-4V profile were revealed by experiments. The tensile model was obtained by uniaxial tensile tests within ranges of temperatures (500–700 °C) and strain rates (5 × 10−5–1 × 10−3 s−1). The creep constitutive model was acquired with stress relaxation experiments in ranges of temperatures (500–700 °C) and pre-strain of 1.5%. Then, the coupled thermo-mechanical model of hot twist-stretch straightening was established. Based on orthogonal experiment strategy, the effects of straightening temperature, stretch strain, and holding time on the bending deflection and torsion angle of profile were investigated systematically and the process was optimized. The straightening accuracy is significantly affected by straightening temperature and holding time. By using optimized process parameters in practical straightening experiments, the deflection/length and angle/length after straightening does not exceed 2‰ and 2.5‰°/mm, respectively, which is basically consistent with the numerical simulation result. 相似文献
13.
Maciej Combrzyski Agnieszka Wjtowicz Anna Oniszczuk Dariusz Karcz Jarosaw Szponar Arkadiusz P. Matwijczuk 《Materials》2022,15(14)
The impact of the amount of durum wheat bran additive used on the selected structural, mechanical, and spectroscopic properties of thermoplastic starch moldings was examined in this study. Bran was added to corn starch from 10 to 60% by weight in the blends. Four temperature settings were used for the high-pressure injection: 120, 140, 160, and 180 °C. The highest value of elongation at break (8.53%) was observed for moldings containing 60% bran. Moreover, for these moldings, the tensile strength and flexural strength were lower (appropriately 3.43 MPa and 27.14 MPa). The highest deformation at break (1.56%) were obtained for samples with 60% bran and injection molded at 180 °C. We saw that higher bran content (50 and 60%) and a higher injection molding temperature (160 °C and 180 °C) significantly changed the color of the samples. The most significant changes in the FTIR spectra were observed at 3292 and 1644 cm−1 and in the region of 1460–1240 cm−1. Moreover, notable changes were observed in the intensity ratio of bands at 1015 and 955 cm−1. The changes observed correspond well with the amount of additive used and with the injection temperature applied; thus it may be considered as a marker of interactions affecting plasticization of the material obtained. 相似文献
14.
In this paper, the duplex stainless steel welded joints were produced by a K-TIG welding system. The weld geometry parameters under different welding speeds were analyzed by combining the morphological characteristics of the keyhole. The microstructure and impact toughness of the base metal and weld metal zone under different welding speeds were studied. The experiment results show that the welding speed has quite an effect on the geometry profile of the weld. In addition, the characteristic parameters of the keyhole can effectively predict the geometry profile of the weld. The test results prove that the microstructure, Σ3 coincidence site lattice grain boundary, and phase boundary of ferrite and austenite have an effect on the impact property of the weld metal zone. When the proportion of the austenite, Σ3 coincidence site lattice grain boundary and random phase boundary increased, the impact property of the weld metal zone also increased. S32101相似文献
15.
Freeman RK 《Seminars in perinatology》2008,32(4):271-Evaluation
Antepartum fetal testing in pregnant patients with hypertensive disorders may be beneficial in preventing stillbirth and hypoxic sequelae in the fetus. The highest risk patients in this category are those with intrauterine growth restriction, superimposed preeclampsia, associated medical complications such as diabetes, systemic lupus erythematosis, chronic renal disease, or history of a prior stillbirth. The current recommended method of primary testing is a twice weekly modified biophysical profile with either a full BPP or a contraction stress test for backup evaluation of those patients with lack of reactivity or decreased amniotic fluid volume on a modified biophysical profile. Even uncomplicated patients with chronic hypertension or pregnancy-induced hypertension carry an increased risk of perinatal mortality and for these patients testing should begin at 33 to 34 weeks gestation. Patients with complications of intrauterine growth restriction, preeclampsia, diabetes, systemic lupus erythematosis, or chronic renal disease should have antepartum testing begin when intervention for fetal indications is judged to be appropriate, usually beginning at about 26 weeks gestation. Doppler velocimetry may be helpful in further evaluation of those patients in the early third trimester with abnormal primary testing. 相似文献
16.
Growth-restricted fetuses are at higher risk for poor perinatal and long-term outcome than those who are appropriately grown. Multiple antenatal testing modalities can help document the sequence of fetal deterioration. The full extent of this compromise is best identified by a combination of fetal biometry, biophysical profile scoring, and arterial and venous Doppler. In the preterm growth-restricted fetus, timing of delivery is critically determined by the balance of fetal versus neonatal risks. In the near-term fetus, accurate diagnosis continues to be a challenge as unrecognized growth restriction contributes to a significant proportion of unexplained stillbirths. In this review, we present an integrated diagnostic and surveillance approach that accounts for these factors. 相似文献
17.
Fetal growth restriction 总被引:1,自引:0,他引:1
Normal fetal growth is determined by the genetically predetermined growth potential and further modulated by maternal, fetal, placental, and external factors. Fetal growth restriction (FGR) is a failure to reach this potential and is clinically suspected if sonographic estimates of fetal weight, size, or symmetry are abnormal. Integration of fetal anatomy assessment, amniotic fluid dynamics, uterine, umbilical, and fetal middle cerebral artery Doppler is the most effective approach to differentiate potentially manageable placenta-based FGR from aneuploidy, nonaneuploid syndromes, and viral infection. Although placental dysfunction results in a multisystem fetal syndrome with impacts on short- and long-term outcome, only cardiovascular and behavioral responses are helpful to guide surveillance and intervention. Early-onset FGR before 34 weeks gestation is readily recognized but challenging to manage as questions about optimal delivery timing remain unanswered. In contrast, near-term FGR provides less of a management challenge but is often missed as clinical findings are more subtle. Once placenta-based FGR is diagnosed, integrating multivessel Doppler and biophysical profile score provides information on longitudinal progression of placental dysfunction and degree of fetal acidemia, respectively. Choosing appropriate monitoring intervals based on anticipated disease acceleration and intervention when fetal risks exceed neonatal risks are the prevailing current management approaches. 相似文献
18.
19.
Chandra Yogal Marianne Borgen Sunila Shakya Biraj Karmarcharya Rajendra Koju Mats P. Mosti Miriam K. Gustafsson Bjrn Olav svold Berit Schei Astrid Kamilla Stunes Unni Syversen 《Nutrients》2022,14(11)
Hypovitaminosis D is prevalent worldwide, and especially in South-Asia. According to the Institute of Medicine (IOM), 25(OH)D levels below 30 nmol/L are defined as vitamin D deficiency (VDD) and levels between 30–50 nmol/L as insufficiency (VDI). Besides its role in calcium homeostasis, it has been postulated that vitamin D is involved in metabolic syndrome. Given the scarcity of data on vitamin D status in Nepal, we aimed to examine the prevalence of VDD and VDI, as well as the determinants and association with metabolic parameters (lipids, HbA1c), in a cohort of women in rural Nepal. Altogether, 733 women 48.5 ± 11.7 years of age were included. VDD and VDI were observed in 6.3 and 42.4% of the participants, respectively, and the prevalence increased by age. Women reporting intake of milk and eggs > 2 times weekly had higher 25(OH)D levels than those reporting intake < 2 times weekly. Women with vitamin D levels < 50 nmol/L displayed higher levels of cholesterol, LDL-cholesterol, triglycerides, and HbA1c. Additionally, a regression analysis showed a significant association between hypovitaminosis D, dyslipidemia, and HbA1c elevation. In conclusion, VDI was prevalent and increased with age. Milk and egg intake > 2 times weekly seemed to decrease the risk of VDI. Moreover, hypovitaminosis D was associated with an adverse metabolic profile. 相似文献
20.
目的 :建立青藤碱的透皮吸收研究方法 ,比较青藤碱渗透小鼠皮肤、裸鼠皮肤、家兔皮肤、大鼠皮肤、猪耳皮肤及人体皮肤的透皮吸收行为。方法 :青藤碱的含量测定采用HPLC法 ,计算透皮速率常数J,比较青藤碱渗透上述 6种实验皮肤的透皮速率常数。结果 :青藤碱透过 6种皮肤的透皮速率常数分别为 46 6 7± 16 35、40 34± 8 40、17 6 0± 9 46、2 3 71± 8 79、44 5 6± 11 2 7、38 33± 13 81。结论 :青藤碱对 6种皮肤的渗透性 ,以裸鼠及猪耳皮肤的透皮速率常数与人体皮肤较为接近。 相似文献