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91.
Background:Decreased platelet (PLT) count is one of the independent risk factors for mortality in intensive care unit (ICU) patients.This study was to investigate the relationship between PLT indices a...  相似文献   
92.
研究小酸浆Physalis minima L.的活性成分。小酸浆的地上部分经乙醇提取,氯仿萃取,D-101大孔树脂柱色谱粗分,Sephadex LH-20、MCI gel CHP 20P、RP-18等色谱柱分离,并通过理化常数和波谱学方法鉴定化合物结构。从小酸浆中分离鉴定了5个化合物,分别为Withaphysalin P(Ⅰ)、14,18-di-O-acetylwithaphysalin C(Ⅱ)、Withaphysalin Q(Ⅲ)、Withaphysalin型化合物1(Ⅳ)、Withaphysalin型化合物2(Ⅴ)。化合物Ⅳ、Ⅴ为新化合物,分别命名为Withaphysalin T、Withaphysalin U。  相似文献   
93.
94.
目的分析高危型人乳头瘤病毒(high-risk human papillomavirus,HR-HPV)阴性的不典型鳞状细胞(atypical squamous cells undetermined significance,ASCUS)和低度鳞状上皮内病变(low squamous intraepithelial lesion,LSIL)患者的随访结果,探讨HR-HPV阴性的ASCUS和LSIL患者的合理处理方法。方法回顾性分析2010年1月1日至2012年12月31日期间,就诊于首都医科大学附属北京朝阳医院妇科门诊,HR-HPV阴性、宫颈液基细胞学为ASCUS和LSIL的356例患者的病理资料,对HR-HPV阴性的ASCUS和LSIL经阴道镜及宫颈活检排除高级别病变的306例患者定期进行HR-HPV随访。HR-HPV检测采用杂交检测法2代(hybird capture-Ⅱ,HC-Ⅱ)。结果 HR-HPV阴性/ASCUS和LSIL患者宫颈上皮内瘤变(cervical intraepithelial lesions,CIN)-Ⅲ及以上病变发病率分别为7.9%和9.1%。HR-HPV阳性/ASCUS和LSIL患者CIN-Ⅲ及以上病变发病率分别是22.9%和17.9%。HRHPV阳性的ASCUS和LSIL患者CIN-Ⅲ及以上病变发病率明显高于HR-HPV阴性患者,差异具有统计学意义(P=0.000)。HRHPV阳性对ASCUS及LSIL患者宫颈高级别病变的阴性预测值分别为87.13%和84.42%。HR-HPV阴性/ASCUS和LSIL患者CIN-Ⅱ及以上病变检出率是14.3%。不同年龄段的HR-HPV阴性/ASCUS和LSIL的患者,宫颈高级别病变患者的发生率不同,差异具有统计学意义(P<0.05)。30~39岁妇女宫颈高级别病变的发生率最高(18.2%)。结论 HR-HPV阴性的ASCUS和LSIL患者发生CIN-Ⅲ及以上病变分别是7.9%和9.1%,CIN-Ⅱ及以上病变达14.3%,30~39岁的HR-HPV阴性/ASCUS和LSIL患者宫颈高级别病变发生率达18%,建议对于HR-HPV阴性的ASCUS和LSIL患者应行阴道镜检查可疑病变部位活检。  相似文献   
95.
目的探讨碳酸酐酶IX(carbonic anhydrase-IX,CA-IX)在宫颈脱落细胞中的表达情况及与高危型人乳头瘤病毒(high risk-human papilloma virus,HR-HPV)感染的关系,分析CA-IX预测宫颈病变自然转归方向的价值。方法运用免疫细胞化学技术观察CA-IX在不同宫颈病变宫颈脱落细胞中的表达,采用HC-Ⅱ测定HR-HPV DNA,定期随访,比较CA-IX表达与HR-HPV感染状态的相关性。结果 CA-IX的表达与HPV的感染存在相关性(χ2=81.8,P=0.000)。低级别〔宫颈炎、宫颈上皮内瘤变(cervical intraepithelial neoplasia,CIN-Ⅰ)〕和高级别(CIN-Ⅱ、CIN-Ⅲ及宫颈癌)宫颈病变,CA-IX的阳性表达率差异有统计学意义(χ2=4.5,P=0.032)。不同HPV感染状态下(持续性感染、一过性感染、无HPV感染),CA-IX表达的阳性率分别为60.6%、38.4%、15.6%,差异具有统计学意义(χ2=11.69,P=0.001)。结论 CA-IX的表达与HPV感染相关,在持续性HPV感染中,CA-IX的表达阳性率较一过性HPV感染、无HPV感染明显升高,提示CA-IX有可能是参与持续HPV感染致宫颈上皮内瘤变的分子标志之一。  相似文献   
96.
Bladder cancer (BC) is a lethal cancer that threatens the health of millions of people. Chemotherapy drug resistance, for example, cisplatin (DDP) resistance, is a huge limitation for BC therapy. PTEN pseudogene-1 (PTENP1) has been identified as a significant biomarker of multiple cancers. Therefore, it is essential to illuminate the molecular mechanism of PTENP1 in BC cell DDP resistance and progression. Serum exosomes were isolated using an ExoQuick precipitation kit. Serum exosomes were round-shaped vesicles of 100 ± 60 nm in size. The expression of PTENP1 was down-regulated in serum exosomes isolated from cisplatin non-responsive patients compared with responsive patients. ROC curves certified the diagnostic value of PTENP1. Apparently, PTENP1 transfection inhibited DDP-resistant BC cell proliferation, migration, cisplatin resistance and facilitated apoptosis. Next, we discovered that PTENP1 was a sponge of miR-103a, while PDCD4 was a target of miR-103a. More importantly, PTENP1 regulated DDP-resistant cell viability, migration, apoptosis and cisplatin resistance by interacting with the miR-103a/PDCD4 axis. In addition, PTENP1 hindered tumor growth of cisplatin-resistant mice. Exosome-derived PTENP1 suppressed the DDP resistance of BC by inhibiting cell proliferation, migration and promoting apoptosis through regulating the miR-103a/PDCD4 axis, representing a targeted therapy for DDP-resistant BC patients.

Bladder cancer (BC) is a lethal cancer that threatens the health of millions of people.  相似文献   
97.
目的探讨西安地区部分人群肺功能的特点,生活习惯和环境等因素与肺功能的关系。方法2012年7—8月对西安地区东郊和北郊共405人进行问卷调查和肺功能检测,并用多元逐步回归分析不同因素对肺功能指标的影响。结果西安地区东郊和北郊人群FVC,PEF和FEF25—75均低于正常预计值,东郊和北郊人群之间肺功能主要指标差异有统计学意义(P〈0.001);肺功能主要指标与年龄增长、性别和肺部疾病呈负相关(P〈0.05)。结论西安地区部分人群肺功能主要指标偏低,为今后该地区呼吸系统疾病防治提供依据。  相似文献   
98.
Standardized Ginkgo biloba leaf extract has been used in clinical trials for its beneficial effects on brain functions,particularly in dementia.Substantial experimental evidences indicated that Ginkgo biloba leaf extract (EGB) protected neuronal cells from a variety of insults.We investigated the effect of EGB on cognitive ability and protein kinase B (PKB) activity in hippocampal neuronal cells of dementia model rats.Rats received an intraperitoneal injection of D-galactose to induce dementia.Forty-eight Spraque-Dawley rats were randomly divided into six groups,including the control group,D-galactose group (Gal),low-dose EGB group (EGB-L),mid-dose EGB group (EGB-M),high-dose EGB group (EGB-H) and treatment group.The EGB-L,EGB-M and EGB-H groups were administered with EGB and D-galactose simultaneously.Y-maze,cresyl violet staining,TUNEL assays and immunohistochemistry staining were performed to detect learning and memory abilities,morphological changes in the hippocampus,neuronal apoptosis and the expressing level of phospho-PKB,respectively.Rats in the Gal group showed decreased abilities of learning and memory,and hippocampal pyramidal cell layer was damaged,while EGB administration improved learning and memory abilities.The Gal group exhibited many stained,condensed nuclei and micronuclei,either isolated or within the cytoplasm of cells (39.5±1.4).Apoptotic cells decreased in the groups of EGB-L (35.9±0.9),EGB-M (16.8±1.0) and EGB-H (10.1±0.8),and there were statistical significances compared with the Gal group.Immunoreactivity of phospho-PKB was localized diffusely throughout the cytosol of cells in all groups,while the immunoreactivity of the Gal group was weak.EGB significantly attenuated learning and memory impairment in a dose-dependent manner,while it could decrease the nmber of TUNEL-positive cells,and increase the activity of PKB.Our results demonstrated that EGB attenuated memory impairment and cell apoptosis in galactose-induced dementia model rats by activating PKB.  相似文献   
99.
Antigens encoded in the region of difference (RD) of Mycobacterium tuberculosis constitute a potential source of specific immunodiagnostic antigens for distinguishing tuberculosis (TB) infection from BCG vaccination. We evaluated the diagnostic potential of specific T-cell epitopes selected from two immunodominant antigens, Rv1985c and Rv3425, from RD2 and RD11, respectively, on the basis of epitope mapping, in TB patients and BCG-vaccinated healthy individuals. Using a whole-blood gamma interferon release assay, a wide array of epitopes was recognized on both Rv1985c and Rv3425 in TB patients. Those epitopes that could specifically discriminate TB infection from BCG vaccination were carefully selected, and the most promising peptide pools from Rv1985c showed a sensitivity of 53.9% and a specificity of 95.5%. When the novel specific peptides from Rv1985c joined the diagnostic antigens in the QuantiFERON-TB Gold In-Tube (QFT-IT) assay, the sensitivity was increased from 86.4% to 96.2%, with no drop in specificity. These results indicate that the peptide pools selected from Rv1985c and Rv3425 have the potential to diagnose TB infection by a method that may be routinely used in clinical laboratories.  相似文献   
100.
AIM: To evaluate immunological protection of nitric oxide (NO) in hepatopulmonary syndrome and probable mechanisms of ischemia-reperfusion (IR) injury in rat liver transplantation.METHODS: Sixty-six healthy male Wistar rats were randomly divided into three groups (11 donor/recipient pairs). In group II, organ preservation solution was lactated Ringer’s solution with heparin 10  000/μL at 4 °C. In groups I and III, the preservation solution added, respectively, L-arginine or NG-L-arginine methyl ester (L-NAME) (1 mmol/L) based on group II, and recipients were injected with L-arginine or L-NAME (50 mg/kg) in the anhepatic phase. Grafted livers in each group were stored for 6 h and implanted into recipients. Five rats were used for observation of postoperative survival in each group. The other six rats in each group were used to obtain tissue samples, and executed at 3 h and 24 h after transplantation. The levels of alanine aminotransferase (ALT), tumor necrosis factor (TNF)-α and NO metabolites (NOx) were detected, and expression of NO synthase, TNF-α and intercellular adhesion molecule 1 (ICAM-1) was examined by triphosphopyridine nucleotide diaphorase histochemical and immunohistochemical staining.RESULTS: By supplementing L-arginine to strengthen the NO pathway, a high survival rate was achieved and hepatic function was improved. One-week survival rate of grafted liver recipients in group I was significantly increased (28.8 ± 36.6 d vs 4 ± 1.7 d, P < 0.01) as compared with groups II and III. Serum levels of ALT in group I were 2-7 times less than those in groups II and III (P < 0.01). The cyclic guanosine monophosphate (cGMP) levels in liver tissue and NOx in group I were 3-4 times higher than those of group II after 3 h and 24 h reperfusion, while in group III, they were significantly reduced as compared with those in group II (P < 0.01). The levels of TNF-α in group I were significantly lower than in group II after 3 h and 24 h reperfusion (P < 0.01), while being significantly higher in group III than group II (P < 0.01). Histopathology revealed more severe tissue damage in graft liver and lung tissues, and a more severe inflammatory response of the recipient after using NO synthase inhibitor, while the pathological damage to grafted liver and the recipient’s lung tissues was significantly reduced in group I after 3 h and 24 h reperfusion. A small amount of constitutive NO synthase (cNOS) was expressed in liver endothelial cells after 6 h cold storage, but there was no expression of inducible NO synthase (iNOS). Expression of cNOS was particularly significant in vascular endothelial cells and liver cells at 3 h and 24 h after reperfusion in group II, but expression of iNOS and ICAM-1 was low in group I. There was diffuse strong expression of ICAM-1 and TNF-α in group III at 3 h after reperfusion.CONCLUSION: The NO/cGMP pathway may be critical in successful organ transplantation, especially in treating hepatopulmonary syndrome during cold IR injury in rat orthotopic liver transplantation.  相似文献   
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