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61.

Background

Microsatellite instability (MSI) is one of the leading mechanisms for the carcinogenesis of gastric cancer. Its prognostic value is controversial.

Methods

Between May 1988 and Oct 2003, a total of 214 gastric cancer patients undergoing curative surgery were enrolled, and their MSI statuses were classified as MSI-H (high) or MSI-L/S (low/stable). The clinicopathologic characteristics of MSI-H and MSI-L/S gastric cancers were compared.

Results

The MSI-H tumors accounted for 11.7?% (n?=?25) of the 214 total gastric cancers. Although not statistically significant, the MSI-H gastric cancers were more frequently located in the lower third of the stomach (64?% vs. 49.2?%) and were more often the intestinal type (72?% vs. 61.4?%) compared to the MSI-L/S gastric cancers. The MSI-H gastric cancers had a significantly better 5-year overall survival (OS) rate (68?% vs. 47.6?%, p?=?0.030) and a trend of a better 3-year disease-free survival rate (71.8?% vs. 55.2?%, p?=?0.076) compared to the MSI-L/S gastric cancers. A multivariate analysis revealed that pathologic TNM stage and MSI status were the independent prognostic factors for OS after curative surgery.

Conclusions

Compared to MSI-L/S tumors, MSI-H tumors are associated with a better OS rate for gastric cancer patients after R0 resection.  相似文献   
62.
BACKGROUND: An increased biosynthesis of nitric oxide (NO) has been implicated in the hyperdynamic circulation and development of collaterals of portal hypertension (PHT) because of its potent vasodilatory effects. NO is synthesized from L-arginine by three different isozymes of nitric oxide synthase (nNOS, iNOS and eNOS). Thus, the expression of inducible NOS (iNOS) might account for NO overproduction in PHT. However, in previous investigations, the role of iNOS in the pathogenesis of PHT gastropathy remained controversial. Our current study was in both molecular and protein levels to determine whether the expression of iNOS is responsible for PHT gastropathy. MATERIALS AND METHODS: PHT was induced experimentally by partial ligation of the portal vein. Fourteen days after partial ligation of the portal vein, the rats were randomly assigned to receive either vehicle or L-NAME (NOS inhibitor) at doses of 5 mg/kg/day, 10 mg/kg/day, or 25 mg/kg/day by gastric lavage twice a day for 1 week. Sham operated rats served as controls. Northern hybridization and in situ hybridization are used to compare the expression of gastric mucosa iNOS mRNA in the PHT rats and the controls. NO was measured by the Griess method after reduction of nitrate to nitrite with nitrate reductase. Immunohistochemical staining was carried out to detect the iNOS protein. In addition, the severity of gross gastric mucosal lesions was evaluated macroscopically by a gross ulcer index. RESULTS: The iNOS expression at both mRNA and protein was prominently increased in PHT rats, accompanied with the enhanced NO production. The gastric mucosa iNOS mRNA and serum NO levels were significantly decreased after L-NAME administration (P < 0.05). However, the markedly reduced gastric mucosal damage in PHT rats was observed only at high does of L-NAME (25 mg/kg/day) administration. CONCLUSION: PHT triggers overexpression of iNOS mRNA and proteins in rat gastric mucosa, but that this alone does not account for PHT gastropathy.  相似文献   
63.
In this study, we present the evaluation of two new ternary ligand (99m)Tc complexes [(99m)Tc(HYNIC tetramer)(tricine)(L)] [L=isonicotinic acid (ISONIC) and 2,5-pyridinedicarboxylic acid (PDA)] as potential radiotracers for tumor imaging. Athymic nude mice bearing MDA-MB-435 human breast cancer xenografts were used to evaluate their biodistribution and metabolic properties. Solution stability data showed that [(99m)Tc(HYNIC tetramer)(tricine)(L)] (L=ISONIC and PDA) had significant decomposition (14% and 35%, respectively) at 6 h in the absence of excess ISONIC or PDA coligand. Biodistribution data clearly showed that [(99m)Tc(HYNIC tetramer)(tricine)(PDA)] had a much lower uptake in most organs of interest than [(99m)Tc(HYNIC tetramer)(tricine)(ISONIC)] during the 2-h study period. Results from metabolism studies revealed that approximately 50% of [(99m)Tc(HYNIC tetramer)(tricine)(ISONIC)] remained intact in fecal samples at 120 min postinjection, whereas only 10% of [(99m)Tc(HYNIC tetramer)(tricine)(PDA)] remained intact in fecal samples. The extent of metabolism correlated well with radiotracer solution stability. The results from this and our previous studies clearly demonstrated that coligands [trisodium triphenylphosphine-3,3',3'-trisulfonate (TPPTS), ISONIC and PDA] have a significant impact on the tumor uptake, excretion kinetics and metabolism of the (99m)Tc-labeled cyclic RGDfK tetramer. Among the three radiotracers evaluated in this tumor-bearing animal model, [(99m)Tc(HYNIC tetramer)(tricine)(TPPTS)] remained the best with respect to blood clearance, tumor uptake and target/background ratios.  相似文献   
64.

Objective  

The current American Joint Committee on Cancer staging system for esophageal cancer is based on lymph node location, irrespective of the number of involved and examined lymph nodes.  相似文献   
65.
Femoral neuropathy can result from diverse etiologies following abdominal surgery. We describe four cases of postoperative femoral neuropathy after proctological procedures that were carried out at our hospital. The related symptoms developed occultly but eventually impaired patient motor or sensory functions in the lower extremities. When the patient fails to address associated suffering, it is easy for clinicians to neglect this type of morbidity. All patients recovered from neuropathy following timely detection of the disease entity confirmed by electromyography and nerve conduction studies, followed by adequate rehabilitation management. We hypothesize that postoperative femoral neuropathy may be closely related to unsuitable applications of self-retaining retractors, rather than being associated with other factors, such as gender, age, surgery time or body mass index (BMI). Furthermore, we used a literature review to examine the pathophysiology, diagnoses and treatment modalities of femoral neuropathy resulting from inappropriate placement of self-retaining retractors. Based on a thorough comprehension of the femoral nerves anatomical course and meticulous placement of retractor blades, these types of iatrogenic complications may be prevented.  相似文献   
66.
Streptococcus pneumoniae, an important pathogen causing sepsis, sinusitis, otitis media, bacterial meningitis and bacterial pneumonia, results in global morbidity and mortality each year. The burden of pneumococcal disease is highest in children and the elderly. Treatment of pneumococcal infection has been hampered by the complexity of the host immune response. In recent decades, the increase of S. pneumoniae strains' resistance to beta-lactam antibiotics and other classes of antimicrobials has made treatment even more complicated. Fortunately, the advent of heptavalent conjugate vaccine confers a high degree of protection against pneumococcal disease and colonization caused by vaccine serotype strains. After the introduction of conjugate pneumococcal vaccine, invasive pneumococcal disease caused by vaccine serotypes and antibiotic-resistant isolates has been reduced. However, naturally transformable pneumococci may escape vaccine-induced immunity by switching their capsular genes to non-vaccine serotypes. Development of cheaper, serotype-independent vaccines based on a combination of protein antigens should be pursued.  相似文献   
67.
Cutaneous angiocentric T-cell lymphoma associated with Epstein-Barr virus.   总被引:1,自引:0,他引:1  
BACKGROUND: Two unusual cases of cutaneous angiocentric T-cell lymphoma were found to be associated with Epstein-Barr virus infection. OBJECTIVE: The objective was to study the clinical course and the response of the disease to conventional chemotherapy. METHODS: Histologic specimens from both patients were studied. Clonal proliferation was assessed by Southern blot hybridization. RESULTS: The disease in both patients was rapidly progressive and responded poorly to aggressive treatment. Biopsy specimens showed infiltration of atypical lymphoid cells with angiocentricity and angiodestruction, which probably resulted in the observed tissue necrosis. Clonal proliferation of Epstein-Barr virus DNA was detected in tissue from primary skin lesions and disseminated nasal lesions. CONCLUSION: Epstein-Barr virus-associated angiocentric T-cell lymphoma in our patients was characterized by an aggressive course and resistance to conventional chemotherapy. A search for Epstein-Barr virus and the human T-lymphotropic virus should be performed in patients with atypical features of cutaneous T-cell lymphoma.  相似文献   
68.
客观结构式临床测验(OSCE)是目前医学教育发展的重要项目之一。中医教育发展受到西方医学教育影响,也逐步发展出中医的客观结构式临床测验。医病沟通是极为重要的临床能力,藉由OSCE能够观察并给与教学回馈以建立医学生的医病沟通能力。教案设计中的剧本撰写与标准化病人训练是OSCE的关键要素,以期达到一致且具有效度的评量。  相似文献   
69.
BACKGROUND/AIMS: Central vein catheters for patients receiving total parenteral nutrition have a high incidence of colonized catheters and catheter-related bloodstream infections. However, the actual incidence and bacterial pattern have not been well studied. This study was undertaken to investigate the difference in bacteriology between colonized catheters and catheter-related bloodstream infections. METHODOLOGY: From January 1997 to March 1998, 354 patients receiving total parenteral nutrition were included in this study. The patients ranged in age from 49 to 80 years, 151 women and 203 men. Colonized catheters and catheter-related bloodstream infections were defined. RESULTS: The culture was performed in 249 catheter tips (249 of 614, 40.6%). Sixty tips were found to have organisms. The organisms cultured from colonized catheters were Gram(+) aerobic bacteria (34, 56.7%), fungi (14, 23.3%), and Gram(-) aerobic bacteria (12, 20%). The organisms cultured from catheter-related bloodstream infections were fungi (16, 64%), Gram(-) aerobic bacteria (5, 20%), and Gram(+) aerobic bacteria (4, 16%). Dermatogenic infection in colonized catheters should be stressed, but systemic fungal infection in catheter-related bloodstream infections should be emphasized. CONCLUSIONS: A striking difference exists in bacterial species between colonized catheters and catheter-related bloodstream infections. Further studies on different treatment strategy for colonized catheters and catheter-related bloodstream infections should be undertaken. The combined approach of a total parenteral nutrition team, sterile protocols, and early diagnosis of fungemia should be advocated for the total parenteral nutrition patients.  相似文献   
70.

Objective

This study examines (a) providers’ and interpreters’ perception of their competition in controlling the content and process of provider–patient interactions, and (b) the challenges to providers’ and interpreters’ collaboration in bilingual health care.

Methods

I recruited 26 professional medical interpreters from 17 languages and 39 providers from 5 specialties to participate in in-depth interviews and focus groups. Grounded theory was used for data analysis to develop themes in areas where providers and interpreters compete and assert their expertise.

Results

Providers and interpreters experience conflicts over their expertise and authority due to their practice in (a) adopting different speech conventions, (b) controlling the other's narratives, and (c) overstepping expertise and role boundaries.

Conclusion

A successful bilingual medical encounter is dependent on the interpreters’ and providers’ ability (a) to understand, communicate, and negotiate their and others’ communicative strategies/goals and (b) be adaptive of and responsive to others’ management of the communicative process.

Practice implications

Authority in bilingual health care should not be established through pre-existing categories or expertise but negotiated and coordinated during the interactive process, which would allow individuals to be adaptive to the issues emerged in the communicative process.  相似文献   
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