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71.
In the present study, two ulcer models—central thyrotropin-releasing hormone (TRH) injection and cold-restraint stress (CRS) application—were compared. Animals were treated either with salmon calcitonin (sCT) or saline intracerebroventricularly (ICV) before CRS exposure or ICV TRH injection. In both models, besides ultrastructural properties, ulcer indexes and lipid peroxidation (LP) and glutathione (GSH) levels of liver and stomach were determined. While TRH treatment did not affect GSH and LP levels of the stomach and led to a slight decrease in hepatic GSH levels. CRS induced a marked reduction in gastric and hepatic GSH and an increase in LP levels of both tissues. sCT pretreatment prevented the reduction of gastric and hepatic GSH levels and morphological damage of both tissues in the CRS group. However, the same treatment did not prevent the TRH-induced reduction of hepatic GSH levels and, interestingly, it worsened the ultrastructural disturbances in the liver. Although sCT prevented macroscopic ulcer formation in both models, it did not totally reverse the microscopic effects of TRH.  相似文献   
72.
Does Helicobacter pylori infection play a role in lung cancer?   总被引:1,自引:0,他引:1  
BACKGROUND: Helicobacter pylori infection is a world-wide common disease and leads to many gastrointestinal and respiratory illnesses. It is suggested that one of these respiratory illnesses is lung cancer. METHODS: Forty-three patients with non-small cell lung cancer and 28 control subjects have been included to this study. H. pylori status of the patients and controls was determined by immunoblot for the detection of IgG (RIDA Blot Helicobacter). All subjects were examined to evaluate the presence of VacA and CagA gene. RESULTS: Seropositivity of anti H. pylori IgG was significantly higher in cancer patients than in control groups, 40 (93%) and 12 (42%), respectively (P<0.01). Although both VacA and CagA seropositivity was high in lung cancer patients, only VacA positivity was statistically significant when compared with control subjects, 35 (81%) and 11 (42%), respectively (P<0.05). CONCLUSION: H. pylori infection may be associated with development of lung cancer.  相似文献   
73.
Peritoneal dialysis (PD) is one of the commonly used choices of continuous renal replacement therapies. Peritoneal membrane is damaged by using solutions with lower biocompatibility, peritonitis episodes, and vintage of PD therapy. Encapsulating peritoneal sclerosis (EPS) is a rare complication of PD and is presented by progressive fibrosis of the peritoneum. Fibrous tissue entrapment of the intestine, leading to complete intestinal obstruction, is referred to as EPS, the most severe form of sclerosing peritonitis. EPS is irreversible fibrosis of the peritoneal membrane usually associated with high rates of morbidity and mortality. Preventive strategies are the best choice of treatment. Also there is no proven effective therapy for EPS; there are only small-sized trials. Herein we present a case of EPS who improved with everolimus plus tamoxifen therapy.  相似文献   
74.
The use of monoclonal antibodies (mAbs) as therapeutic tools has increased dramatically in the last decade and is now one of the mainstream strategies to treat cancer. Nonetheless, it is still not completely understood how mAbs mediate tumor cell elimination or the effector cells that are involved. Using intravital microscopy, we found that antibody-dependent phagocytosis (ADPh) by macrophages is a prominent mechanism for removal of tumor cells from the circulation in a murine tumor cell opsonization model. Tumor cells were rapidly recognized and arrested by liver macrophages (Kupffer cells). In the absence of mAbs, Kupffer cells sampled tumor cells; however, this sampling was not sufficient for elimination. By contrast, antitumor mAb treatment resulted in rapid phagocytosis of tumor cells by Kupffer cells that was dependent on the high-affinity IgG-binding Fc receptor (FcγRI) and the low-affinity IgG-binding Fc receptor (FcγRIV). Uptake and intracellular degradation were independent of reactive oxygen or nitrogen species production. Importantly, ADPh prevented the development of liver metastases. Tumor cell capture and therapeutic efficacy were lost after Kupffer cell depletion. Our data indicate that macrophages play a prominent role in mAb-mediated eradication of tumor cells. These findings may help to optimize mAb therapeutic strategies for patients with cancer by helping us to aim to enhance macrophage recruitment and activity.  相似文献   
75.
Women of reproductive age (WRA) need adequate nutrient intakes to sustain a healthy pregnancy, support fetal growth, and breastfeed after childbirth. However, data on women''s dietary intake in low‐ and middle‐income countries (LMICs) are limited, and assessment of differences between dietary intakes of pregnant or lactating women compared with that of nonpregnant, nonlactating (NPNL) women is untested. Using single, multiple‐pass 24‐h dietary recall data from a sample of WRA residing in rural Bangladesh, we examined women''s dietary intakes for energy, protein, calcium, iron, vitamin A, and dietary diversity for three groups: NPNL (n = 2,903), pregnant (n = 197), and lactating women (n = 944). We used equivalence testing to examine similarity in adjusted intakes for pregnant versus NPNL women and lactating versus NPNL women with a predetermined equivalence threshold based on recommendations specific for each reproductive stage. On average, both pregnant and lactating women had insufficient intakes for all dietary measures. Although statistically significant differences were observed between pregnant and NPNL women for energy intake and dietary diversity and between lactating and NPNL women for energy and protein intake, the magnitudes of these differences were too small to reject equivalence. Statistical similarity was also evident in all micronutrients and dietary diversity for both two‐group comparisons. Understanding statistical differences and similarities between dietary measures of women in distinct reproductive stages has important implications for the relevance, appropriateness, and evaluation of maternal diet‐enhancing interventions in LMICs, especially during pregnancy and lactation, when demand for macronutrients and micronutrients is elevated.  相似文献   
76.
Surgery is a stressful experience. Many minor interventions have been shown to cause considerable anxiety in patients, but whether arthroscopy leads to such anxiety is not well-known. Methods for lowering perioperative anxiety have been sought and listening to music or watching a movie have been recommended. The method of permitting patients to watch their own endoscopy has been studied infrequently. Our aim in this study was to find out the effect of watching simultaneous arthroscopic views on postoperative anxiety. A total of 63 patients were randomly divided into two groups: those watching their own arthroscopy formed group W, while patients that were only verbally informed formed group NW. The mean age of patients in both groups were 33 and 34, respectively. Meniscal surgery was the most commonly performed procedure (49/63 patients). The patients filled in state scale of State-trait anxiety inventory (STAI) forms and the study questionnaire (SQ) prepared for this study, just before and after the arthroscopy. Group W had significantly lower postoperative scores of STAI-S, whole questionnaire (Q-score) and all but one of individual statements in SQ. Having a previous operation history did not affect STAI scores. Age and level of education was not correlated with any of the studied parameters either. The ratio of patients that were pleased with the arthroscopy experience in group W and NW were 94 and 63%, respectively. Watching live arthroscopic views has led to a significant decrease in postoperative anxiety and worries about the surgery and the postoperative period, while increasing overall understanding and satisfaction of the patient.  相似文献   
77.
Abstract The clinical and immunological data from 4 patients with generalized prepubertal periodontitis are presented. The peripheral blood neutrophil chemo-taxis was measured using zymosan activated sera as the chemoattractant. All of the 4 patients have shown depressed neutrophil chemotaxis compared to those of the healthy controls. Peripheral blood lymphocyte subpopulations were analysed by double-coloured flow cytometry using monoclonal antibodies for the receptors CD2. CD3. CD4. CD8. CD19. CD29, CD45RA +, 34,29dK, CD56, CD11b/CD18. Lymphocytes bearing CD3 receptors showed a significant decrease compared to those of the controls. Natural killer cells were lowered in 3 of the 4 cases. All of the patients showed a higher increase in CD11b/CD18 expression. The evaluation of CDllb/CD18 receptor in peripheral blood leukocytes may be of help explaining the rôle of neutrophils in the pathogenesis of the disease.  相似文献   
78.
BACKGROUND/AIMS: A significant association between variations in amino acid sequences resides between 2209-2248 nucleotides of HCV non-structural 5A (NS5A) gene, and response to interferon treatment has been proposed. The aim of this study was to determine whether the amino acid sequence changes in ISDR could be correlated to response to alpha interferon treatment in Turkish patients infected with HCV genotypes 1b and 1a. METHODS: Thirty-nine patients with chronic C virus infection (35 and 4 patients with genotype 1b and 1a, respectively), receiving 3x3-5 MU of interferon a-2b for six months were included in the study. Following PCR amplification of the region from pre-treatment serum samples, the products were directly sequenced. The amino acid sequence of NS5A was compared with the published sequence for HCV-J (AA 2209-2248). Mutant type was defined as three or more amino acid mutations, and intermediate type as 1-3 amino acids in this region. Otherwise, they were defined as the wild type (no amino acid mutations). HCV RNA serum viremia levels were analyzed by branched DNA assay. RESULTS: Eighteen patients were responders (R; 46%), whereas 21 patients were non-responders (NR; 54%). Amino acid changes in both R and NR groups did not show significant difference. Intermediate or wild type strains were detected in both groups. CONCLUSIONS: In this study, we could not determine a significant association between number of amino acid changes in NS5A2209-2248 and response to interferon treatment. In the majority of the patients, it seems that amino acid sequences in this region are well conserved.  相似文献   
79.
Anticancer agents may cause side effects and some of which may be dose dependant. It is important for clinicians to see the effects on tissues histopathologically. The aim of this study was to investigate the effects of topotecan (hycamtin®), a topoisomerase I inhibiting anticancer agent, on nasal, buccal, and lingual mucosa of rabbits. The study was carried out in two groups each consisting of 20 rabbits. Rabbits in group I received i.v. topotecan (0.5 mg/kg once daily) for 3 days. Rabbits in group II received i.v. topotecan (0.25 mg/kg once daily) for 3 days. In group I and II, biopsies from the nasal, buccal, and lingual mucosa were taken on the fourth (1 day after the 3-day topotecan treatment) and 15th day (12 days after the 3-day topotecan treatment). Light and transmission electron microscopic (TEM) observations have shown that nasal mucosa was not affected by topotecan administration. Topotecan treatment resulted in the formation of some ulcerative lesions in the lingual mucosa especially on the lower surface of the tongue. On the dorsal surface, the epithelium showed highly edematous and degenerating cells and separations in the stratum granulosum. In the buccal mucosa, effects were similar. In lingual and buccal mucosa, healing was observed on the 15th day. The oral (lingual and buccal) mucosal side effects of topotecan were observed as reversible and not dose dependent. It was concluded that these side effects are not severe, and topotecan may be used safely in cancer treatment.  相似文献   
80.
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