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1.
目的:调查青少年近视患者配戴渐进多焦眼镜的现状,分析其对眼部参数的影响。方法:随机抽查配戴渐进光眼镜的近视患者214名,对其进行视光学检查,包括屈光度、斜视度、AC/A率、辐接近点和融合范围等项目,并调查其心理感受。其检查结果与256名年龄相匹配的戴用单焦眼镜的近视患者相对照,分析其变量的变化。结果:配戴渐变多焦眼镜的近视患者中140例无不适感觉,满意程度明显高于对照组;屈光度平均为-3.5D,约半数患者(48.6%)存在不同程度的外隐斜,其中8位是间歇性外斜患者,没有融合能力,辐辏近点大于20 cm;平均AC/A率为(2.95±1.49),平均融合力为+16.41°~-7.06°,平均辐转近点为(72.63±24.42)mm。实验组除AC/A率低于对照组(t=3.52,P<0.05),且与屈光度无明显相关(r=-0.0318,P>0.05)外,其余检查与对照组之间没有显著性差别。结论:渐进多焦眼镜可以引起AC/A率降低,并有可能通过掩饰间歇性外斜患者 的症状而耽误其治疗。因此,渐进多焦眼镜虽然普遍受青少年近视患者欢迎,但验配中仍存在适应证选择问题,青少年在验配时最好在医生的指导下进行。  相似文献   
2.
组织型纤溶酶原激活剂及其抑制物的变化与冠心病的关系   总被引:3,自引:0,他引:3  
目的:观察冠心病患者纤溶活性的变化及其在冠心病发病中的作用,探讨其临床意义。方法:用酶联免疫双抗夹心(ELISA)法测定58例冠心病患者血浆中组织型纤溶酶原激活剂(t—PA)及纤溶酶原激活抑制物-1(PAI-1)抗原含量,反映纤溶-抗纤溶活性的变化,并对冠心病患者组与对照组纤溶指标进行不同性别间的比较。结果:急性心肌梗死、不稳定心绞痛患者PM-1的含量、PAI-1/t—PA比值明显高于对照组,且急性心肌梗死患者PM-1的含量较不稳定心绞痛患者显著为高。但t—PA在急性心肌梗死、不稳定心绞痛患者均无显著降低。患者组及对照组不同性别间纤溶及抗纤溶水平均未见有显著差异。结论:血栓性疾病与纤溶系统的异常有密切关系。纤溶系统活性的变化及纤溶-抗纤溶的平衡失调在缺血性心脏病的发生、发展中起着重要作用。  相似文献   
3.
The bacterial ghost (BG) platform system is a novel vaccine delivery system endowed with intrinsic adjuvant properties. BGs are nonliving Gram-negative bacterial cell envelopes which are devoid of their cytoplasmic contents, yet maintain their cellular morphology and antigenic structures, including bioadhesive properties. The main advantages of BGs as carriers of subunit vaccines include their ability to stimulate a high immune response and to target the carrier itself to primary antigen-presenting cells. The intrinsic adjuvant properties of BGs enhance the immune response to target antigens, including T-cell activation and mucosal immunity. Since native and foreign antigens can be carried in the envelope complex of BGs, combination vaccines with multiple antigens of diverse origin can be presented to the immune system simultaneously. Beside the capacity of BGs to function as carriers of protein antigens, they also have a high loading capacity for DNA. Thus, loading BGs with recombinant DNA takes advantage of the excellent bioavailability for DNA-based vaccines and the high expression rates of the DNA-encoded antigens in target cell types such as macrophages and dendritic cells. There are many spaces within BGs including the inner and outer membranes, the periplasmic space and the internal lumen which can carry antigens, DNA or mediators of the immune response. All can be used for subunit antigen to design new vaccine candidates with particle presentation technology. In addition, the fact that BGs can also carry piggyback large-size foreign antigen particles, increases the technologic usefulness of BGs as combination vaccines against viral and bacterial pathogens. Furthermore, the BG antigen carriers can be stored as freeze-dried preparations at room temperature for extended periods without loss of efficacy. The potency, safety and relatively low production cost of BGs offer a significant technical advantage over currently utilized vaccine technologies.  相似文献   
4.
Objective To investigate the effects of Donglian Capsule(the combination of Ophiopogonis Tuber Polysaccharide with Rhizoma Coptidis Alkaloids, OPRA for short, Component of Chinese medicine)on early insulin resistance in experimental diabetic rats. Methods The animal model of insulin resistance in 2 type diabetic was established by injecting low dose of STZ in 60 high fat-fed SD rats. After one week, the successful models were randomly divided into 4 groups: untreated, high and low OPRA-treated, mefformin-treated group, Meanwhile, a normal control group was designed. After four weeks, the differences of FBG, PG, INS and C-P were compared among the groups. Results The OPRA can significantly reduced the level of serum TC and FBG, increased the C-E ]Lightened the IRI(P<0.01). Conclusion The OPRA can reduce the level of serum TG and FBG, and decrease insulin resistance to protect the β-cell function.  相似文献   
5.
Objective To investigate the effects of Donglian Capsule(the combination of Ophiopogonis Tuber Polysaccharide with Rhizoma Coptidis Alkaloids, OPRA for short, Component of Chinese medicine)on early insulin resistance in experimental diabetic rats. Methods The animal model of insulin resistance in 2 type diabetic was established by injecting low dose of STZ in 60 high fat-fed SD rats. After one week, the successful models were randomly divided into 4 groups: untreated, high and low OPRA-treated, mefformin-treated group, Meanwhile, a normal control group was designed. After four weeks, the differences of FBG, PG, INS and C-P were compared among the groups. Results The OPRA can significantly reduced the level of serum TC and FBG, increased the C-E ]Lightened the IRI(P<0.01). Conclusion The OPRA can reduce the level of serum TG and FBG, and decrease insulin resistance to protect the β-cell function.  相似文献   
6.
7.
Colorectal cancer is the second leading cause of cancer-related deaths in the United States.Recent studies prove that though chemotherapeutic agents are being used for the treatment of colon cancer,they become non-effective when the cancer progresses to an invasive stage.Since consumption of certain dietary agents has been linked with various cancers,fruit juices have been investigated for their consistently protective effect against colon cancer.The unique biochemical composition of fruit juices is responsible for their anticancer properties.In this review,the chemo-preventive effect of fruit juices such as pomegranate and citrus juices against colon cancer are discussed.For this purpose,the bioavailability,in vitro and in vivo effects of these fruit juices on colorectal cancer are highlighted.Moreover,there is a scarcity of studies involving human trials to estimate the preventive nature of these juices against colon cancer.This review will support the need for more preclinical tests with these crude juices and their constituents in different colorectal cancer cell lines and also some epidemiological studies in order to have a better understanding and promote pomegranate and citrus juices as crusaders against colon cancer.  相似文献   
8.
BackgroundSpinal muscular atrophy (SMA) is a neuromuscular disease caused by homozygous deletion of SMN1 exons 7 and 8. However, exon 8 is retained in some cases, where SMN2 exon 7 recombines with SMN1 exon 8, forming a hybrid SMN gene. It remains unknown how the hybrid SMN gene contribute to the SMA phenotype.MethodWe analyzed 515 patients with clinical suspicion for SMA. SMN1 exons 7 and 8 deletion was detected by PCR followed by enzyme digestion. Hybrid SMN genes were further analyzed by nucleotide sequencing. SMN2 copy number was determined by real-time PCR.ResultsSMN1 exon 7 was deleted in 228 out of 515 patients, and SMN1 exon 8 was also deleted in 204 out of the 228 patients. The remaining 24 patients were judged to carry a hybrid SMN gene. In the patients with SMN1 exon 7 deletion, the frequency of the severe phenotype was significantly lower in the patients with hybrid SMN gene than in the patients without hybrid SMN gene. However, as for the distribution of SMN2 exon 7 copy number among the clinical phenotypes, there was no significant difference between both groups of SMA patients with or without hybrid SMN gene.ConclusionHybrid SMN genes are not rare in Japanese SMA patients, and it appears to be associated with a less severe phenotype. The phenotype of patients with hybrid SMN gene was determined by the copy number of SMN2 exon 7, as similarly for the patients without hybrid SMN gene.  相似文献   
9.
Circular dichroism calculation for natural products   总被引:1,自引:0,他引:1  
Determination of the absolute configuration (AC) is often a challenging aspect in the structure elucidation of natural products. When chiral compounds possess appropriate chromophore(s), electronic circular dichroism (ECD) may provide a powerful approach to the determination of their absolute configuration. Recently, ECD calculations by time-dependent density functional theory (TDDFT) have come to be used more commonly. In the present review, we give several examples of recent studies using TDDFT-calculated ECD spectra for the AC determination of natural products.  相似文献   
10.
通过概述土家医、壮医、苗医、蒙医、藏医、侗医、畲医、维吾尔医、傣医等民族医的特色理论和诊疗技法,阐释民族医药在防治肝癌中的应用情况。我国部分少数民族在防治肝癌方面有丰富的用药经验和外治方法,主要通过驱毒、扶正等方法指导肝癌防治,在未病先防、既病防变、改善相关症状等方面发挥着一定的优势。  相似文献   
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