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排序方式: 共有396条查询结果,搜索用时 15 毫秒
21.
Expression of 8-hydroxy-2’-deoxyguanosine in gastric carcinomas   总被引:1,自引:0,他引:1  
Reactive oxygen species may be involved in the progression of gastric carcinomas. To clarify whether the pathology of gastric carcinoma are related to oxidative DNA damage, the expression of 8-hydroxy-2'-deoxyguanosine (8-OHdG) was examined in 30 patients with gastric carcinomas. Methods: The expression of 8-OHdG and apoptosis in the gastric carcinoma were measured using the methods of immunocytochemistry and deoxynucleartididyl transferase-mediated dUTP-biotin nick end labeling (TUNEL), respectively. Results: Of the 30 cases, 25(83%) showed stronger immunoreactivity than normal control. The patients with poorly differentiated gastric carcinoma had a larger tumor size and higher labeling indices of TUNEL- and 8-OHdG-positive cells than those with well and moderately differentiated gastric carcinoma. Conclusion: Our findings suggest that oxidative DNA damage is increased in association with necroinflammation in chronic gastric injuries and determination of 8-OHdG is useful in assessing high-grade malignancy in gastric carcinomas.  相似文献   
22.
Objective To study the effect of natural killer (NK) cells on graft-versus-host disease (GVHD) after H-2 haploidentical bone marrow transplantation (BMT) in mice. Methods Murine model of H-2 haploidentical BMT was established by using Balb/c (H-2d) mouse as recipient, and Balb/c(H-2d)×C57BL/6 (H-2b) (H-2d/b) mouse as donor. Lethally irradiated Balb/c (H-2d) mice were transplanted with the bone marrow cells from Balb/c(H-2d)×C57BL/6(H-2b) (H-2d/b) mice containing donor spleen cells and/or NK cells. GVHD and survival rates were studied by observation of clinical manifestations and pathological changes. ResultsIn the group of bone marrow spleen cells, GVHD was induced in 90% mice; but in the group plus with low amount of NK cells,GVHD was induced in 20% mice; and in the group transplanted with high amount of NK cells, GVHD was induced only in 10% mice. Compared to the group transplanted only with BM plus spleen cells, the incidences of GVHD in the latter two groups decreased significantly (P<0.01) and the survival rates at different periods of 15, 30, 45 and 60 days increased obviously (P<0.01 ). Conclusion In mouse H-2 haploidentical BMT, alloreactive NK cells can reduce the incidence of GVHD and increase the survival rate.  相似文献   
23.
Objective: To explore the effects of thiazolidinediones (TZDs) pioglitazone on proliferation and differentiation of human preadipocytes. Methods :Omental adipose tissue biopsies were obtained from 15 patients who were undergoing elective open-abdominal surgery. The primary culture and differentiated induction of human preadipocytes were performed, and the human preadipo-cytes were treated with pioglitazone at different concentrations at proper moments. Dynamic morphological changes of the human preadipocytes were observed, and their proliferation and differentiation were assessed with Colorimetric MTT Assay and Oil Red O Staining. Results:After 24 hours and 72 hours with pioglitazone, 0.1 μmol/L (μmol/ml) pioglitazone increased the MTT values of the human preadipocytes by 25.3% and 34.8% ,respectively(P < 0.05), while 1 μ mol/L pioglitazone by 27.4% and 26.6%(P< 0.05), compared with the control group without pioglitazone. The human preadipocytes with pioglitazone cumulated more adipose in the endochylema than those without pioglitazone obviously. 0.1 μmol/L pioglitazone increased the differentiation degree of the human preadipocytes differentiated for 8-10 days by 44.81% and 1 μmol/L pioglitazone by 53.76%(P < 0.05). Conclusion:Thiazolidinediones pioglitazone may significantly promote the proliferation and differentiation of the human omental preadipocytes.  相似文献   
24.
Purpose. To reduce the systemic toxicity and prolong the systemic presence of l-(2-chloroethyl)-3-cyclohexyl-l-nitrosourea (CCNU), a lipid-based drug carrier was designed and characterized. Methods. The degree of CCNU association with lipid vesicles composed of 1,2-dimyristoyl-sn- glycero-3-phosphocholine (DMPC) and l,2-dimyristoyl-sn-glycero-3-phosphoglycerol (DMPG) (1:1, m/m) was characterized and the drug decomposition rates of lipid-drug complexes were monitored. Effects of lipid association on drug potency against medulloblastoma cells and total systemic drug exposure in rats were determined. Results. At a CCNU:lipid molar ratio greater than 1:5, more than 90% of the drug was associated with the lipid vesicles. In aqueous suspensions, lipid association significantly reduced the first-order drug decomposition rate. In addition, lipid-associated CCNU exhibited a 4-fold increase in drug sensitivity with medulloblastoma cells. IC50 values for CCNU admixed and encapsulated with lipid vesicles were 18 ± 4.9 and 14.0 ± 2.2 M, respectively, compared to 83 ± 11.0 M for free CCNU. When administered to rats, lipid-associated CCNU increased the AUC (area under the concentration-time curve) of CCNU by approximately 2-fold (20.46 ± 2.15 compared to 39.59 ±1.87 gmin/ml), and the terminal half-life (t1/2) by almost 9-fold (17 ± 9 compared to 147 ± 48 min) over free CCNU. Despite the increase in total systemic drug exposure, rats treated with lipid-associated CCNU exhibited a significantly lower frequency of acute neurotoxicity. Conclusions. These data indicate that CCNU associated with lipid vesicles may increase drug stability, potency, and systemic exposure in rats.  相似文献   
25.
AIMS: The diagnosis of psychogenic urinary dysfunction (PUD) is one of exclusion, particularly from urologic and neurologic causes, and is usually accompanied by more obvious psychologic/ psychiatric features. We here describe patients with PUD who were diagnosed in our uro- neurological laboratory. MATERIALS AND METHODS: We reviewed the digitized records of 2,300 urodynamic cases treated in the past 6 years to identify patients who fulfilled the diagnostic criteria of PUD. All 2,300 patients had completed a urinary questionnaire and undergone both electromyography (EMG)-cystometry and a detailed neurological examination. In addition, pressure-flow analysis, neurophysiology tests including sphincter EMG analysis, and MRI of the brain and spinal cord were performed as applicable. RESULTS: PUD was seen in 16 cases (0.7%): 6 men, 10 women, mean age 37 years. Lower urinary tract symptoms (LUTS) included overactive bladder (OAB) alone in 5, difficult urination alone in one, and both in 10. LUTS commonly occurred in particular situations, for example, OAB only while riding the train. Some patients showed extremely infrequent toileting. The urodynamic findings were normal except for increased bladder sensation (50%) for OAB and acontractile detrusor (31%) for difficulty. The final diagnosis was conversion reaction in six followed by anxiety in four. CONCLUSIONS: PUD patients experienced the situational occurrence of OAB and/or difficult urination and, in some patients, extremely infrequent toileting. The main urodynamic abnormalities were increased bladder sensation and acontractile detrusor. However, even in cases suggestive of PUD, a non-PUD pathology behind the symptoms should be explored.  相似文献   
26.
目的研究17β-雌二醇(17β-E2)对子宫内膜异位症(内异症)患者在位子宫内膜间质细胞β-catenin mRNA和蛋白表达的影响,探讨Wnt/β-catenin信号通路在介导雌激素促进内异症发生发展的作用。方法体外分离培养内异症患者在位子宫内膜间质细胞。用不同浓度17β-E2处理子宫内膜间质细胞48 h;此后选用10-10mol/L 17β-E2处理子宫内膜间质细胞12、24和48 h,逆转录聚合酶链反应(RT-PCR)和免疫印迹法(Western blotting)检测17β-E2处理前后子宫内膜间质细胞β-catenin mRNA和蛋白的表达水平。同法分析雌激素受体拮抗剂ICI182,780(10-6mol/L)对17β-E2促进β-catenin mRNA和蛋白表达的影响。免疫组织化学染色观察17β-E2作用后β-catenin在子宫内膜间质细胞中的定位。结果17β-E2能明显促进内异症患者在位子宫内膜间质细胞β-catenin mRNA和蛋白的表达,并呈剂量和时间依赖性,于10-10mol/L作用48 h最明显。雌激素受体拮抗剂ICI182,780能明显抑制17β-E2对子宫内膜间质细胞β-catenin mRNA和蛋白的表达。免疫组织化学染色发现17β-E2能促进β-catenin在子宫内膜间质细胞核内的表达。结论雌激素可能通过激活Wnt/β-catenin信号通路促进内异症在位子宫内膜的异位种植。  相似文献   
27.
臧佳佳  高艳锋  韩书芝  平芬 《临床荟萃》2022,37(10):931-933
目的 探讨急性嗜酸性粒细胞肺炎的临床特点及诊疗方法。方法 对该患者行经气管肺部灌洗和肺组织活检,并给予糖皮质激素治疗,观察患者肺部影像学变化趋势。结果 经气管肺部灌洗和肺组织活检确诊后,给予糖皮质激素治疗,患者症状明显好转,胸部炎症渗出完全吸收。结论 急性嗜酸性粒细胞肺炎的临床症状不典型,可经气管肺部灌洗和肺组织活检确诊,且糖皮质激素治疗快速有效,一般预后良好。  相似文献   
28.
Cerebral magnetic resonance imaging (MRI) was performed on 18 patients with migraine characterized by aura consisting of both visual symptoms and paresthesias. Fifteen headache-free individuals of the same age range were used as controls. Records were randomized and read in blind fashion by two neuroradiologists. Small subcortical white matter lesions were seen in three migraine cases and two controls. In one migraine case cortical infarctions were seen. In two controls, small areas of increased density similar to those in migraine were seen. No consistent correlation of migraine or its duration with cerebral atrophy was found. It is concluded that identification of both these MRI findings (small subcortical white lesions and cerebral atrophy) as significantly associated with migraine is doubtful.  相似文献   
29.
30.

Background/purpose

We evaluated the long-term umbilical appearance and patient/parent satisfaction at follow-up after umbilical hernia repair (UHR).

Methods

In a retrospective review of 128 children who underwent UHR and were followed up for over 5 years, satisfaction was assessed using e-mailed questionnaires and attached photographs of the umbilicus.

Results

The survey response rate was 80.3% by parents, 79.5% by patients, and 72.1% using photographs. The median follow-up period was 7.6 (range, 5.3–10.1) years. The satisfaction rate was 78.9% among parents and 91.5% among patients; however, eight patients (8.5%) reported dissatisfaction with the results. The main reason for dissatisfaction was the shallow depth of the umbilicus (parents, 10/20; patients, 5/8). During the follow-up period, satisfaction increased in 14 cases (14.7%) and decreased in 10 cases (10.5%). Superior hooding was considered an ideal shape for the umbilicus. Concomitant laparoscopic surgery and higher age at surgery were significantly associated with dissatisfaction in parents (P = 0.045) and patients (P = 0.046), respectively. Large defect size was significantly associated with decreased satisfaction during the follow-up period (P = 0.030).

Conclusion

E-mail surveys are useful for long-term follow-up after UHR. Patients with these above risk factors should receive long-term follow-up with careful attention to patient satisfaction.

Level of evidence

Type of study: prognosis study, level II.  相似文献   
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