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71.
BACKGROUND: The aim of this study was to determine by radioisotope use whether the sentinel lymph node concept is applicable to esophagogastric cancers. In addition, we examined radioactivities of hot nodes and compared them with the sensitivity of a gamma probe. METHODS: The subjects were 44 patients, 23 with esophageal cancer and 21 with gastric cancer. The day before surgery, patients underwent endoscopic submucosal injection of 184 MBq of Tc-99m tin colloids into sites surrounding the tumor. Radioisotope activities of lymph nodes dissected at surgery were measured with a well-typed gamma detector and each lymph node was categorized as a hot or cold node. Histopathology of the lymph nodes was examined by hematoxylin and eosin staining. Radioisotope activities and histopathological results were compared to determine whether radioisotope flow reflects lymphatic flow to regional lymph nodes. The sensitivity of a gamma probe was measured in a laboratory study and the relation between the radioisotope activities of hot nodes and the detection sensitivity of the gamma probe was examined. RESULTS: Histopathological examination revealed lymph node metastasis in 18 of the 44 patients. In 15 of these 18 patients, metastatic foci were recognized in at least one hot node. Subsequent analysis was performed on the 36 patients in whom tumor invasion was confined to the muscle layer and in whom endoscopic clippings had not been applied. Lymph node metastases were observed in 12 of these 36 patients. In these 12 patients, at least one hot node was positive for metastasis. The laboratory study revealed that the gamma probe was able to detect radioisotope activities of >/=0.02 micro Ci. Thirty-two of 63 (51%) esophageal cancer hot nodes and 16 of 86 (19%) gastric cancer hot nodes showed radioisotope activities below the detection sensitivity of the gamma probe. CONCLUSION: The sentinel lymph node concept is applicable to patients with esophageal and gastric cancers; however, further studies are necessary to identify hot nodes accurately using gamma probes.  相似文献   
72.
To assess dermal absorption of nicotine from tobacco leaves in relation to Green Tobacco Sickness (GTS), urinary cotinine concentrations were measured in 80 male tobacco-growing farmers and in 40 healthy males (controls) who did not handle wet tobacco leaves in Kelantan, Malaysia. Among non-smokers, urinary cotinine levels in farmers were significantly higher than those of controls; farmers with urinary cotinine of 50 ng/ml/m2 or above showed eye symptoms more frequently than those below this level (p<0.05). Farmers who did not wear protective equipment had subjective symptoms more frequently than those who used the equipment (p<0.05); some of these symptoms were seen more frequently in organophosphate (Tamaron) users than in non-users. As tobacco farmers evidence a risk of nicotine poisoning from tobacco leaves, assessment including GTS together with effects of pesticides will be necessary.  相似文献   
73.
Protein transduction by poly-arginine   总被引:1,自引:0,他引:1  
Protein transduction methods have been developed utilizing the delivery of peptides and proteins into eukaryotic cells by the protein transduction domain (PTD). Initially, the PTD domain was developed from the sequences from HIV-1 TAT, HSV VP-22 and antennapedia homeoprotein. Recently, several novel PTDs were developed and has been used as a valuable strategy for transduction of therapeutic protein. We developed a novel, high efficiency PTD (11 arginine) based on the TAT sequence and used 11R for the regulation of intracellular signal cascades. PTD can deliver proteins and other bioactive compounds and therefore serves as a very useful strategy for the development of therapeutic agents.  相似文献   
74.
Background. Assessment of malignant potential in gastrointestinal stromal tumors (GISTs) is still problematic. The maximum tumor diameter and the mitotic index are generally used as an index of malignancy of GISTs. The Ki-67 labeling index has recently been used as an index of cell growth, and the prognosis of GISTs was reported to be significantly poor when the value of this index was 10% or higher. Methods. Clinicopathological and immunohistological factors were analyzed in 15 patients who underwent surgical resection of gastric stromal tumors at our department between April 1997 and July 2002. The patients were divided into metastasis/recurrence and benign groups. Also, the relationship of changes in the Ki-67 labeling index to the degree of malignancy in recurrent lesions was assessed in an 84-year-old woman who underwent five reoperations because of recurrences in the peritoneum. Results. Significant differences were noted between the metastasis/recurrence and benign groups in relation to the mean maximum tumor diameter (186.7 ± 80.8mm vs 41.3 ± 22.9mm), mitotic index (88.3 ± 5.0/50 high-power fields [HPF] vs 3.0 ± 2.9/50 HPF), and the Ki-67 labeling index (11.4 ± 2.5% vs 0.01 ± 0.51%). In the patient who had metastasis to the liver 3.5 years after initial operation and underwent five reoperations before death, the intervals until detection of recurrence tended to be shortened gradually. The Ki-67 labeling index varied with each operation, and tended to be higher at the time of reoperations than at the initial operation. Conclusion. The maximum tumor diameter, mitotic index, and Ki-67 labeling index were useful as an index of malignancy for gastric stromal tumor. The efficacy of surgical resection alone may be insufficient in patients with disseminated metastasis to the peritoneum.  相似文献   
75.
A case of distant metastasis to mesh-plug prosthesis in gastrointestinal cancer is presented herein. An 88-year-old man had received mesh-plug repair with high ligation for a recurrence of a right inguinal hernia. Six months later, advanced gastric cancer and advanced transverse colon cancer were detected, and therefore a distal gastrectomy and partial colectomy were performed. Two weeks after the operation, the patient complained of right groin tenderness, and the mesh-plug prosthesis was removed to control any infection. A histopathological investigation demonstrated adenocarcinoma in the plug prosthesis. The patient died of carcinomatosis peritonei 45 days after the last operation.  相似文献   
76.
To investigate the changes in the principal subunit of N-methyl-D-aspartate (NMDA) receptor 1 (NR1) following the transient ischemia and postischemic hypothermia, in situ hybridization was used in the gerbil hippocampus. One of the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors, Glutamate receptor 2 (GluR2) was also investigated to compare with NR1. Even at 1 day, NR1 and GluR2 mRNAs in the CA1 region were reduced following ischemia. Although postischemic hypothermia prevented almost all the neuronal cell death by ischemia and inhibited the reduction of NR1 and GluR2 mRNAs in the CA1 region after 7 days, the downregulation of NR1 mRNA in the CA2 region was observed even at 1 day. This change was specific for NR1 and not for GluR2. These results suggest that the changes in NR1 and GluR2 receptors at the mRNA level would occur in spite of postischemic hypothermia. The phenomenon in the CA2 region may play an important role to rescue neuronal cell death by ischemia.  相似文献   
77.
Purpose. To obtain an improved characterisation of the raffinose-water solid-solid and solid-liquid state diagram, and to study the thermophysical behaviour of the solid amorphous phase. This information is expected to shed light on the potential of rafTinose as a pharmaceutical excipient, for stabilising labile preparations at high temperatures. Methods. X-ray diffraction, scanning electron microscopy, polarised-light microscopy, differential scanning calorimetry (DSC) and thermo-gravimetric analysis (TGA) were applied to study raffinose pentahydrate and its behaviour during progressive dehydration. Results. Isothermal dehydration of raffinose pentahydrate led to its gradual amorphisation, but also to minor changes in the diffractograms, suggesting the probability of lower stable hydrates. Their existence was confirmed by DSC. Anhydrous raffinose was found to be completely amorphous, and this was supported by the gradual disappearance of birefringence during dehydration. In contrast, electron micrographs, taken during the dehydration process, exhibited no changes in the original ultrastructural crystal morphology. The widths of the glass-to-fluid transitions and the absolute specific heats of crystalline and amorphous phases in the vitreous and fluid states were used to estimate some structural and relaxation characteristics of amorphous raffinose-water mixtures. Conclusions. Raffinose forms the most 'fragile' glass of those pharmaceutical excipients for which data are available. In its thermomechanical properties, it is superior to trehalose and should therefore be effective as a long-term stabiliser for dried biopharmaceutical preparations at temperatures up to 65°C.  相似文献   
78.
BACKGROUND: The relationship between ascites, as detected by preoperative computed tomography (CT), and peritoneal metastasis of gastric cancer requires clarification because of its likely significance for clinical outcome. METHODS: A retrospective analysis of 293 patients with advanced gastric cancer investigated the association between preoperative CT findings of ascites and surgical findings of peritoneal washing cytology and peritoneal metastasis. RESULTS: Forty-five of 293 patients (15%) presented with ascites on preoperative CT. Positive ascites on CT predicted the presence of free tumor cells with 40% sensitivity and 97% specificity, and peritoneal metastasis with 51% sensitivity and 97% specificity. Ascites on CT was an independent prognostic factor by univariate (P < .001) and multivariate (relative risk, 2.03; 95% confidence interval, 1.39-2.96; P < .001) analyses. The median survival time was 6.0 months in patients with positive ascites on CT. CONCLUSIONS: The presence of ascites on CT suggests the presence of peritoneal metastasis and indicates a poor prognosis. The presence of peritoneal metastasis should be confirmed by diagnostic laparoscopy in gastric cancer patients with ascites.  相似文献   
79.
Ffteen cases of peripheral T cell lymphoma were studied to evaluate the respective properties of various histologic types using enzyme histochemical and ultrastructural examinations in addition to immunological methods. Eleven cases in an ATLA negative group manifested various histologic patterns such as IBL like, pleomorphic and Lennert's lymphomas in comparison with the relatively monomorphic proliferation of neoplastic lymphoid cells in the 4 ATLA positive cases. The presence of neoplastic clear cells is characteristic of peripheral T-cell malignancies, and is likely to be found in CD4 lymphomas. There is an occasional reaction of epithelioid histiocytes and plasma cells with eosinophils, the former being designated Lennert's lymphoma and the latter IBL like T-cell lymphoma. Immunological examination revealed four immunophenotypic patterns: (1) CD2+3+4+8+, (2) CD2+ 34+8, (3) CD2+3+48+, and (4) CD2+3+4+8+, but did not provide information concerning the intimate relationship between histologic types and immuno phenotyes. β-Glucuronidase reactivity, however, contributed to the distinction between helper and suppressor T cell malignancies, suggesting its usefulness for distinguishing these two cell types and their malignant counterparts.  相似文献   
80.

Purpose

The clinical implications of mucinous components in rectal tumors, especially with regard to the efficacy of neoadjuvant chemoradiotherapy, remain unclear.

Methods

One hundred and thirty rectal cancer patients who received curative resection after neoadjuvant chemoradiotherapy were retrospectively reviewed. Patients were classified into 3 groups according to the proportion of extracellular mucin: low (<5 %), moderate (5–25 %), and high (>25 %).

Results

There were 82 (63.1 %), 26 (20.0 %), and 22 (16.9 %) patients in the low, moderate, and high mucin groups, respectively. Patients with a high mucinous tumor component were significantly more likely to have an advanced tumor stage (p = 0.010) and a shorter disease-free (p = 0.002) and distant recurrence-free survivals (p < 0.001), whereas the mucinous tumor component showed no correlation with local recurrence (p = 0.101). A high mucinous component was also an independent predictive factor for a shorter disease-free survival (p = 0.041, hazard ratio = 2.56) and distant recurrence-free survival (p = 0.001, hazard ratio = 5.74) according to a multivariate analysis.

Conclusions

Because the mucinous components showed little correlation with local recurrence, mucinous cancer should not be a determining factor for chemoradiotherapy. However, the frequent occurrence of metachronous distant metastasis among patients with a high mucin component makes this a possible indicator for more robust postoperative adjuvant treatment and close surveillance of recurrence.
  相似文献   
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