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991.
药物诱导狗Ⅰ型糖尿病的研究   总被引:5,自引:0,他引:5  
To evaluate the efficiency and toxic and side effect of the combined chemical inducer for Type I diabetes mellitus, Type I diabetes in 9 adult dogs were induced with alloxan(50 mg.kg-1) and streptozotocin (30 mg.kg-1) with vein injection. After 7-14 days, the blood glucose of 5 male dogs was kept on high levels [mean value was (22.7 +/- 3.2) mmol.L-1], exogenous insulin was (21.4 +/- 2.4) U.day-1. Three female dogs died in 7 days after they had been injected with the combined inducers. Alloxan-streptozotocin combination administration reduced the dosage of each drug, and decreased the toxic and side effect of each drug. The results suggest that this method has a high rate of success to induce Type I diabetes male dogs.  相似文献   
992.
肝脏外伤的诊断和治疗   总被引:1,自引:1,他引:0  
随着诊断和救治水平的提高 ,加之通信联络和交通条件的改善 ,肝外伤的总病死率已显著下降。然而 ,严重肝外伤的总病死率和并发症发生率仍分别高达 11%和 2 2 % ,因此正确处理严重肝外伤是创伤外科中的重大课题之一。1 肝外伤的发生率和致伤原因  战时肝外伤的发生率约占腹部战伤的 2 6 .7% ,平时约占交通事故的 16 %~ 30 % ,和平时期钝性肝外伤约占6 8.8%~ 90 %。李宜雄等报道钝性伤占 93.8% ,其中车祸48.9% ,摔伤 32 .0 % ,直接撞击伤 19.1%。平时肝外伤的致伤原因除刀伤、火器伤和摔伤外 ,随着工农业现代化建设工程的增多和交通网的…  相似文献   
993.
Gastrodia elata is an achlorophyllous and fully mycoheterotrophic orchid which obtains carbon and other nutrients from Armillaria species in its life cycle. Many researchers suggested that plant hormones, as signing molecules, play a central role in the plant–fungi interaction. In the process of Armillaria gallica 012 m cultivation, both exogenous indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) distinctly stimulated the growth of mycelia in solid media. The differential expression genes (DEGs) of A. gallica 012 m with IAA versus blank control (BK) and IBA versus BK were investigated. The results showed that more than 80% of DEGs of the IAA group were coincident with the DEGs of the IBA group, and more than half of upregulated DEGs and most of the downregulated DEGs of the IAA group coincided with those DEGs of the IBA group. Above research implied that A. gallica 012 m could perceive IAA and IBA, and possess similar responses and signaling pathways to IAA and IBA. The overlapping differential genes of the IAA group and IBA group were analyzed by GO term, and the results showed that several DEGs identified were related to biological processes including positive regulation of the biological process and biological process. The downregulated NmrA-like and FKBP_C genes might be benefit to the growth of mycelia. Those results can explain that exiguous IAA and IBA improved the growth of A. gallica to some extent. We speculate that IAA and IBA are signaling molecules, and regulate the expression of growth-related genes of A. gallica 012 m by the same signaling pathway.  相似文献   
994.
Chen  Yang  Hou  Xuewen  Yang  Yifeng  Ge  Qianqian  Zhou  Yan  Nie  Shengdong 《Journal of digital imaging》2023,36(2):688-699
Journal of Digital Imaging - Lung cancer manifests as pulmonary nodules in the early stage. Thus, the early and accurate detection of these nodules is crucial for improving the survival rate of...  相似文献   
995.
The poly(l -lactic acid) (PLLA)/carbon nanomaterials composite foams with hierarchical surface microstructural and internal conductive pathways are successfully prepared by a simple crystallization-assisted rapid phase separation (CARPS). The dimension and morphology of carbon nanomaterials can induce different crystallization forms to construct the hierarchical surface microstructure, and they are distributed on the phase interface of solvent and non-solvent to form conductive pathways. It is found that the heterogeneous nucleation of nanomaterials promotes a significant increase in crystallinity, and a stacked granular structure formed on the surface promotes the increase of the water contact angle to 148.7°. Foams with interconnecting pore structures contribute to the formation of 85.3% porosity and 12.33 g g−1 oil absorption. Carbon nanomaterials are distributed on the pore walls of the porous foam, which converts the foam from an insulating material to a conducting polymer. Furthermore, the uniform distribution of nanomaterials significantly affects the thermal stability of the PLLA. In belief, the multifunctional biodegradable foam, prepared by a CARPS method, makes it promising for industrial production and has potential applications in electrical conductivity, oil-water separation, and many other fields.  相似文献   
996.
Compared to the charge–charge interaction, the role of the dipole-dipole interaction has long been ignored in the phase behaviors of charged macromolecules in solutions. Charged macromolecules in solutions exhibit rich phase behaviors due to their complexity and they have been studied extensively. Phase separation can happen for charged macromolecules in the presence of monovalent salt, multivalent salt, and oppositely charged polymers, surfactants, etc., and for more advanced charged macromolecules such as polyzwitterions and polyampholytes, the phase diagram is even richer. In this perspective, the unacknowledged role of dipole-dipole interaction in the phase behaviors of charged macromolecular solutions will be introduced. Dipolar polymers can form complex, self-regulating structures which can be employed in various fields from drug-delivery systems to next-generation polymers. More importantly, it will shed light on how some of the life's basic and coherent structures such as biomolecular condensates and membrane-less organelles are assembled and built by charged biomacromolecules such as DNA, RNA, and proteins.  相似文献   
997.
大肠癌新相关基因HSU17714的染色体定位研究   总被引:6,自引:0,他引:6  
Cai X  Zhang Y  Geng L 《中华肿瘤杂志》1997,19(3):177-179
目的确定大肠癌新相关基因HSU17714的染色体定位。方法采用强化荧光原位杂交技术(FISH),以生物素化酪胺强化荧光原位杂交信号。结果80.0%(128/160)的间期细胞和59.8%(104/174)的中期分裂相可见到明显集中的HSU17714基因的杂交信号,相应荧光R带分析中,85.1%(40/47)在22号染色体上1区3带处有杂交信号。结论HSU17714基因定位于22q13。  相似文献   
998.
人原发性肝细胞癌核基质蛋白的研究   总被引:6,自引:2,他引:4  
Wu S  Liu Z  Qiu YQ 《中华肿瘤杂志》1997,19(5):339-341
目的比较正常肝与原发性肝细胞癌(HCC)核基质蛋白的异同,观察是否有HCC特异性核基质蛋白的存在。方法用双向电泳方法比较了3例正常肝和8例HCC核基质蛋白成分。结果正常肝和HCC的核基质蛋白组成极为相似,但在HCC中发现至少有4个HCC的特异性核基质蛋白。其中以分子量为62000、等电点为5.3的蛋白最具代表性,它存在于所研究的8例HCC中。其余3个HCC特异性蛋白亦存在于大多数HCC中。3例正常肝组织中未见有这4个HCC特异性核基质蛋白。结论HCC确实有HCC特异性核基质蛋白的存在,它的发现可能会为HCC的发生、发展、发病机理的研究提供一个新途径。  相似文献   
999.
Cai Q  Rahn RO  Zhang R 《Cancer letters》1997,119(1):99-107
Several dietary flavonoids such as quercetin, luteolin and genistein have been suggested to have cancer chemopreventive effects, although the mechanisms are not fully understood. In the present study, the effects of these flavonoids as antioxidants were investigated in the following systems: (1) production of hydrogen peroxide (H2O2) and superoxide anion (O2*-), (2) lipid peroxidation induced by FeCl2 in rat liver, and (3) formation of 8-hydroxy-2'-deoxyguanosine (8-OHdG) induced by either UV or Fenton reaction in calf thymus DNA. The results showed that quercetin and luteolin were equally potent in scavenging H2O2, with genistein having a moderate effect. Quercetin and luteolin had a potent inhibitory effect on O2*- generation by xanthine/xanthine oxidase while genistein had a moderate effect. Quercetin and luteolin were potent in inhibiting lipid peroxidation induced by FeCl2 in rat liver while genistein had a very weak inhibitory effect. All the test compounds had a potent quenching effect on 8-OHdG formation induced by UV light irradiation, with the order of effects being genistein > luteolin > quercetin. Of the test compounds, luteolin exhibited the most potent quenching effect on Fenton-induced 8-OHdG formation. The scavenging of oxygen free radicals, the inhibitory effect on lipid peroxidation and the quenching effect on 8-OHdG formation by quercetin, luteolin and genistein may, at least in part, be responsible for their anticarcinogenic effects.  相似文献   
1000.
The presence of natural carbohydrate-binding antibodies may play a role in host defence against malignant cells in addition to elicitation of an immune response by artificial carbohydrate antigens. Human serum contains immunoglobulin G(2) (IgG) fractions with selectivity to alpha- and to beta-galactosides, respectively, irrespective of the type of blood group of the donor. To determine whether these naturally occurring subfractions may have any relevance for tumor disease control, their binding to malignant cells was ascertained by cytofluorimetric assays in vitro with a number of human tumor cell lines of different histogenetic origin. The affinity of cell binding was comparable to that of binding to lactosylated or melibiosylated neoglycoconjugates as model ligands in solid-phase assays and K-D values were found to be in the range of 5-300 nM. Cross-reactivity of the anomer-selective subfractions to the other type of ligand was observed to be rather low. When the IgG contents of plasma samples of patients with diverse types of lung cancer were assessed, the concentrations of both galactoside-binding immunoglobulin G subfractions were significantly increased in association with presence of small cell lung carcinoma and of metastatic lesions to the lung without any marked change in the overall IgG plasma level. Such an apparently general enhancement was seen for patients with adenocarcinoma and included both subfractions with no impact on their percentage in the total IEC content. When detergent extracts of tumor and tumor-free specimens of the same patient were analyzed with the affinity purified antibody subfractions to comparatively determine ligand presentation, increases in sugar-inhibitable binding were especially noted for the tumor tissue of small cell lung carcinomas and apparently tumor-free samples of cases with lung metastasis. Material from other types of lung cancer revealed no significant indication for disease-related alterations with the exception of carcinoids. These data demonstrate that plasma levels and ligand expression for two types of natural galactoside-binding immunoglobulin G fractions can show nonuniform responses in patients within the class of lung cancer. They encourage to deliberately monitor these parameters of the natural carbohydrate-directed antibody fractions in cancer patients with various types of disease to clarify the clinical significance of respective malignancy-associated changes.  相似文献   
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