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101.
目的:近期研究发现,壳聚糖纳米化后,不仅可改善其溶解性,还可提高其生物学功能。拟建立壳聚糖纳米粒的制备方法,并对壳聚糖纳米粒的表征及抗肿瘤生物学效应进行初步研究。方法:实验于2006-08/2007-05在浙江省医学科学院生物工程所完成。①建立壳聚糖纳米粒的制备方法:将壳聚糖粉末溶于乙酸溶液,用NaOH调节其pH为5,采用三聚磷酸钠为凝聚剂,进行离子交联来制备壳聚糖纳米颗粒。通过离心和冷冻干燥得到壳聚糖纳米粒粉末。②纳米粒的表征:经超声得到壳聚糖的悬浊液,用透射电镜来观察纳米颗粒的外观形态;用动态光散射仪来测定纳米颗粒的粒径大小与分布。③采用MTT法对壳聚糖纳米粒体外抗肿瘤生物学效应进行了初步研究。结果:①透射电镜下观测到了稳定、均一的颗粒;激光粒度分析仪测量发现纳米粒粒径大小在300nm左右,粒径分布较窄。②500mg/L的壳聚糖纳米粒对Hela细胞的抑制率为27%;对SMMC-7721细胞的抑制率为23%;对BGC-823细胞的抑制率为29%;对MCF-7细胞的抑制率最高,达55%。结论:建立的壳聚糖纳米粒的制备方法可靠,并证明其体外具有较好的抗肿瘤作用。  相似文献   
102.
Morphometry of human leukocytes   总被引:14,自引:0,他引:14  
Schmid-Schonbein  GW; Shih  YY; Chien  S 《Blood》1980,56(5):866-875
In order to establish quantitative models of leukocyte functions, several morphometric parameters on individual white cells are needed. These include the diameter, volume, and membrane area of the cells and their nuclei in the undeformed state. A stereologic method was used to obtain these quantities from transmission electron microscopy of random sections through human white blood cells (neutrophils, lymphocytes, monocytes, and eosinophils). In order to estimate possible artifacts due to preparation of the cells for transmission electron microscopy, a detailed comparison with light microscopy was made. The results show that undeformed white cells in isotonic solution are spherical with many membrane foldings and have a significantly smaller diameter than that measured on blood smears. A method of chemical fixation was employed so that the shrinkage due to fixation of the cells is below the resolution of light microscopic measurements. Further, it was shown that all leukocytes, including lymphocytes, have much more membrane area than is needed to cover their volumes, and this membrane area remains constant when the cell is hypotonically swollen.  相似文献   
103.
In this study, we retrospectively evaluated 37 consecutive patients who underwent stand-alone anterior lumbar interbody fusion (ALIF); for indications that included degenerative disc disease, concordant pain on discography, disc space collapse of more than 50%, and failure of nonoperative management for at least 4 consecutive months. Patient demographics, procedural data, and prospective Short Form 36 General Health Survey composite scores were collected. Mean follow-up was 24.2 months. In this cohort of patients with degenerative disc disease, there was no loosening or migration of implants. Stand-alone ALIF using a threaded interbody fusion device provided excellent clinical results and return-to-work rates with few complications. Increased lordosis was associated with increased subsidence and less favorable outcome. Patients with a transitional segment displayed relatively smaller increases in lordosis and better outcomes than patients without a transitional segment.  相似文献   
104.
OBJECTIVE: Individuals with obsessive-compulsive disorder (OCD) who have compulsive hoarding behavior are clinically different from other OCD-affected individuals. The objective of this study was to determine whether there are chromosomal regions specifically linked to compulsive hoarding behavior in families with obsessive-compulsive disorder. METHODS: The authors used multipoint allele-sharing methods to assess for linkage in 219 multiplex OCD families collected as part of the OCD Collaborative Genetics Study. The authors treated compulsive hoarding as the phenotype of interest and also stratified families into those with and without two or more relatives affected with compulsive hoarding. RESULTS: Using compulsive hoarding as the phenotype, there was suggestive linkage to chromosome 14 at marker D14S588 (Kong and Cox logarithm of the odds ratio [LOD] [KAC(all)=2.9]). In families with two or more hoarding relatives, there was significant linkage of OCD to chromosome 14 at marker C14S1937 (KAC(all)=3.7), whereas in families with fewer than two hoarding relatives, there was suggestive linkage to chromosome 3 at marker D3S2398 (KAC(all)=2.9). CONCLUSIONS: The findings suggest that a region on chromosome 14 is linked with compulsive hoarding behavior in families with OCD.  相似文献   
105.
Tang  Fuk-hay  Xue  Cheng  Law  Maria YY  Wong  Chui-ying  Cho  Tze-hei  Lai  Chun-kit 《Journal of digital imaging》2023,36(3):1081-1090
Journal of Digital Imaging - Tumor phenotypes can be characterized by radiomics features extracted from images. However, the prediction accuracy is challenged by difficulties such as small sample...  相似文献   
106.

Aim

To assess composite endpoints combining glycaemic control (HbA1c < 7.0%, ≤ 6.5% or < 5.7%) with weight loss (≥ 5%, ≥ 10% or ≥ 15%) and without hypoglycaemia with tirzepatide in type 2 diabetes (T2D).

Materials and Methods

Data from the phase 3 SURPASS programme were evaluated post hoc by trial. Participants with T2D were randomized to tirzepatide (5, 10 and 15 mg), placebo (SURPASS-1,5), semaglutide 1 mg (SURPASS-2) or titrated basal insulin (SURPASS-3,4). The proportions of participants achieving the composite endpoints were compared between tirzepatide and the respective comparator groups at week 40/52.

Results

The proportions of participants achieving an HbA1c value of less than 7.0% with 5% or more weight loss and without hypoglycaemia ranged from 43% to 82% with tirzepatide across the SURPASS-1 to -5 trials versus 4%-5% with placebo, 51% with semaglutide 1 mg and 5% with basal insulin (P < .001 vs. all comparators). The proportions of participants achieving an HbA1c value of less than 7.0% with 10% or more, or 15% or more weight loss and without hypoglycaemia were significantly higher with all tirzepatide doses versus comparators across trials (P < .001 or P < .05). Similar results were observed for all other combinations of endpoints with an HbA1c value of 6.5% or less, or less than 5.7%, with more tirzepatide-treated participants achieving these endpoints versus those in the comparator groups, including semaglutide.

Conclusions

Across the SURPASS-1 to -5 clinical trials, more tirzepatide-treated participants with T2D achieved clinically meaningful composite endpoints, which included reaching glycaemic targets with various degrees of weight loss and without hypoglycaemia, than those in the comparator groups.  相似文献   
107.
Myelitis and Guillain-Barré syndrome occurring concurrently after varicella infection is very rare. A 34-year-old man presented with progressive flaccid tetraparesis, facial palsy, respiratory failure, sensory loss and urinary incontinence one week after varicella infection. Clinical, imaging and electrodiagnostic studies supported the diagnosis of myelitis and Guillain-Barré syndrome. He improved with intravenous acyclovir and gammaglobulin.  相似文献   
108.
OBJECTIVE: This study was designed to investigate the possible synergism of atenolol and nitrendipine on blood pressure (BP) and blood pressure variability (BPV) reductions, baroreflex sensitivity (BRS) amelioration, and organ protection in hypertensive rats. METHOD: The dose was 20 mg/kg for atenolol, 10 mg/kg for nitrendipine and 20 + 10 mg/kg for the combination of these two drugs. In an acute study, a single dose was given via a catheter previously inserted into the stomach in spontaneously hypertensive rats (SHR).  相似文献   
109.
旱莲草化学成分旱莲甙A和旱莲甙B的分离和鉴定   总被引:7,自引:1,他引:7  
张梅  陈雅妍 《药学学报》1996,31(3):196-199
自旱莲草(Eclipta alba(L.)Hassk)全草中分得4个三萜化合物,经理化常数测定和光谱(IR,MS,UV,1HNMR,13CNMR和13C-1HCOSY)解析,2个已知的三萜类化合物分别为刺囊酸(echinocysticacid,I)和齐墩果酸(oleanlicacid,II),另2个为新化合物,分别命名为旱莲甙A(eclip-tasaponinA,II)和旱莲甙B(ecliptasaponinB,IV)。I和II为首次从鳢肠属植物中获得。  相似文献   
110.
瘤体内注射卡铂和消痔灵对荷瘤鼠的抗肿瘤作用及其毒性   总被引:3,自引:0,他引:3  
目的:观察瘤内注射(it)卡铂(CBP)和消痔灵(XZL)的抗肿瘤作用。方法:选用小鼠S180实验体瘤模型,it XZL,it及静脉注射(iv)CBP治疗,测定各组小鼠的瘤重,体重,脾指数和胸腺指数。结果:与生理盐水(NS)组比较,iv CBP 30mg/kg,it XZL 10ml/kg和it CBP 30,60mg/kg的抑瘤率分别为20.23%和,25.6%,27.4%和41.9%,脾指数变化分别为-41.0%,12.2%-28.4和-49.2%,胸腺指数变化分别为-8.5%,33.0%,-5.3%和-12.8%。结论:it CBP和XZL均有抗肿瘤作用,CBP降低荷瘤鼠免疫器官指数,而ZL则增加荷瘤鼠免疫器官指数。  相似文献   
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