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61.
A bstract A new instrument for the immobilization and hemostasis of an anastomotic site is described for use during minimally invasive off-pump direct coronary artery bypass (MID-CAB). The mechanism is based on air suction of the heart surface. The instrument is unique in that it can avoid direct temporary of the distal end of the coronary artery to control bleeding. With this instrument, anastomosis of left intemal thoracic artery to left anterior descending artery (LAD) was successfully performed on three pigs. Additionally, in six patients the LAD could be stably and securely immobilized in the beating heart by the present instrument. The instrument is hereinafter referred as "MIDCAB doughnut," which can make an operative field motionless and bloodless without distal snaring.  相似文献   
62.
In this study, we analyzed T cell receptor (TCR) gene rearrangements in tumor-infiltrating lymphocytes (TIL) freshly obtained from 15 patients with head and neck cancer using the reversely transcribed polymerase chain reaction (RT-PCR) method. These TILs showed preferential expression of Vα10, Vα8 and Vα1, detected in 13 (87%), 11 (73%), and 9 cases (60%), respectively. The TCRVβ gene revealed diversity without preferential usage. The head and neck region is exposed to bacteria and viruses, so it is possible that the tumor site can become infected and accumulate T cells involved in infection and inflammation. Therefore, we also investigated TCR gene usage in T cells infiltrating in chronic sinusitis mucosa to address the question of whether the Vα1, Vα8, and Vα10 subfamilies are characteristic in TIL from squamous cell carcinoma of head and neck. TCR Vα10 gene usage was also the most common in Vα segment in T cells infiltrating the sinus mucosa, but Vα and Vα8 were not detected in the T cells in sinusitis. These results indicate that the Vα10 subfamily, the preferred T cell population in both TIL and T cells in inflammatory disease, might he involved mainly in inflammation or infection. On the other hand, Vα1 and Vα8 appear to be relatively specific populations for antitumor immunity in head and neck cancer.  相似文献   
63.
Summary Forty-nine out of 54 male workers engaged in the production of an epoxy compound, t-methyl-3-phenylglycidate, showed skin symptoms in varing degrees that may be due to the skin-irritative effect of the compound. The exposed workers were also shown to have subjective symptoms which may be related to the irritative property of the compound on surface tissue. Laboratory examinations on the blood obtained from the exposed workers showed significantly higher values of leukocyte concentration as compared with the non-exposed controls. This was chiefly caused by the increase of neutrophilic granulocytes and T-cell lymphocytes. Serum IgA levels of the exposed workers were shown to be significantly lower than those of the control group. Hemoglobin concentration, hematocrit value and red cell count of the exposed workers remained at the same level as those of the control subjects. Liver or kidney damage was not found in biochemical analyses on the sera of exposed workers.  相似文献   
64.
Purpose: We examined whether bone marrow-derived dendritic cells (DCs) could induce antitumor immunity when a chemotherapeutic drug was added. Methods: CT26 (a murine colon cancer cell line syngeneic with BALB/c) and CT26-bearing mice were treated with mitomycin C (MMC) intraperitoneally (i.p.). Next, mice immunized with a coinjection of DCs and MMC-treated CT26 (i.p.) were given an intradermal inoculation of CT26. Finally, CT26-bearing mice were treated with MMC (i.p.) with or without DCs, given peritumorally. Results: Although the inoculated tumor was not rejected in the control mice, CT26 was rejected in 50% of the mice injected with MMC alone. Apoptosis was observed in the MMC-treated CT26 cells in vitro and in vivo. Immunization with DCs and apoptotic CT26 cells, but not with apoptotic CT26 alone, gave protection against tumor challenge in 7 of 13 mice. A significantly higher level of cytotoxic T-cell activity and interferon-γ production was seen in the protected mice. When MMC (i.p.) treatment was followed by peritumoral DC injection in the CT26-bearing mice, remarkable therapeutic effects were observed. Conclusion: DCs can collaborate with chemotherapy-induced apoptotic tumor cells and elicit improved antitumor immunity, probably through the acquisition of tumor-associated antigens from apoptotic tumor cells. Received: January 7, 2002 / Accepted: September 3, 2002 Acknowledgments. We thank Dr. Kazuo Kinoshita for his useful advice on using flow cytometry. This research was partly supported by the Ministry of Education, Culture, Sports, Science and Technology (No. 11671160). Reprint requests to: S. Yamasaki  相似文献   
65.
The patient was a 48-year-old male who was diagnosed with unstable angina. He had worsening cardiogenic shock during coronary angiography. Emergency coronary artery bypass grafting (CABG) was performed. He had a methicillin-resistant Staphylococcus aureus (MRSA) mediastinitis on day 22 after CABG. Drains were placed in the anterior mediastinum, left thoracic cavity, and abscess cavity, and another drain was placed in the mediastinal space for continuous cleansing with povidone iodine, oxydol. For antibiotics, teicoplanin (TEIC) was administered intravenously and to the local site via the cleansing drain for about one month. No MRSA was detected by culture in discharges from the mediastinal drain. Inflammatory findings were improved, and the patient was discharged and resumed everyday life without recurrence of inflammation as of eight months. Although the number of cases of MRSA mediastinitis is small and accumulation of cases is necessary to investigate therapeutic methods and selection of antibiotics, our department will select closed continuous cleansing and TEIC for antibiotics as the first choice for MRSA mediastinitis, and accumulate cases to investigate its efficacy.  相似文献   
66.
Achieving coverage after digital injury is crucial, because simple skin defects can expose essential structures such as tendons or bones. This is particularly true on the dorsal surfaces of the digits, where the skin provides the only protection for the tendons. However, longitudinal skin defects of the digit have not been specifically identified in the literature and there have been few reports focusing on longitudinal dorsal skin defects. Here we report on the use of a bipedicle flap for reconstruction of complex longitudinal dorsal tissue defects of the digits, including those associated with tendon or bone damage.  相似文献   
67.
Treatment strategies for hepatic metastasis from colorectal cancer   总被引:3,自引:0,他引:3  
Hepatic micrometastases of the parenchyma adjacent to a macroscopic lesion were detected in 17 of 31 resected liver metastases. Fifty-nine micrometastatic lesions were detected in total; 26 lesions were situated in the portal vein (PV), 22 in the central vein (CV), 5 in the bile duct (BD), and 6 in the sinusoid (SS). A histological study confirmed the direct invasion of the macrometastatic cancer cells into the adjacent PV, CV, BD, and SS. According to the tumor doubling time, the mean diameter of the macrometastases in 19 remnant livers was calculated to have been 0.57±0.87 cm at the time of the primary resection. The calculated diameter of 3 of these 19 macrometastases was found to be less than 0.01 cm, the minimum implantable size, indicating that the cancer recurrence in these specimens may have developed from macroscopic metastatic lesions as a satellite, and not from the primary tumor. In 13 patients who received doses of 5250 mg or more of 5 fluorouracil (FU) via the hepatic artery, the cumulative disease-free rate 2 years postoperatively was 100%; this value was 47.6% in 11 patients who received less than 5250 mg of 5 FU via the hepatic artery, and 0% in 39 patients who received no chemotherapy (P<0.005). These results suggest that anatomical hepatic resection for satellite lesions, combined with prophylactic hepatic arterial chemotherapy for micrometastases, decreases the recurrence rate of hepatic metastases in the remnant liver.  相似文献   
68.
To investigate whether a selective intercellular communicationexists between transformed epithelial cells and their counterparts,the homologous and heterologous communication capacities offour rat liver epithelial cell lines were compared with theirexpression of transformed phenotypes. All four cell lines showedreasonably good homologous junctional communication capacity,as measured by the dye-transfer assay. In heterologous co-cultures,the non-transformed cell line IAR 20 did not communicate withthe transformed cell lines IAR 6–1 or IAR 27 F. Thesetwo cell lines showed a high degree of transformed phenotypessuch as cell morphology, growth in soft agar and expressionof -glutamyltrans-peptidase activity. Another cell line IAR27 E, showed the least degree of transformation and it communicatedwith IAR 20 cells. Thus, it appears that there is an inversecorrelation between the extent of expression of transformedphenotypes by rat liver epithelial cells and their ability tocommunicate with non-transformed counterparts. There was noheterologous intercellular communication between any combinationof IAR 27 E, IAR 27 F and IAR 6–1 cell lines.  相似文献   
69.
Intracranial hemorrhage is a fatal complication associated with aplastic anemia. We have encountered four patients who experienced six episodes of intracranial hemorrhage (intracerebral hemorrhage; 3, subarachnoid hemorrhage; 2, and subdural hematoma; 1,). Intracranial hemorrhage occurred without traumatic episodes, and was followed by frequent hemorrhagic episodes in other parts of about one year duration. This disease is considered to recur after a short interval. The site, type and degree of intracranial hemorrhage varied, and therefore intracranial hemorrhage seemed to be caused not only by thrombocytopenia but also by multifactorial hemorrhagic tendency. Transfusion of platelet rich plasma, and administration of Glycerol and steroids produced good results for conservative therapy. Continuous spinal drainage for subarachnoid hemorrhage was a relatively safe and useful means of management. In the patients who showed precipitous deterioration, the CT scan findings indicated that the high-density-area was diffusely spread with an unclear border, just like "contusional hemorrhage". For such severe cases, blood evacuation with craniotomy and emergency splenectomy are considered to be valuable.  相似文献   
70.
The effect of aging on 11C-N-methylspiperone binding to living human striatum was demonstrated using positron emission tomography. The 11 normal volunteers (22 to 72 years old) participated in this study. The uptake of 11C-N-methylspiperone in the brain following intravenous injection was highest in the striatum in individual subject. And the uptake in the striatum only gradually increased until the end of the study. The uptake of 11C-N-methylspiperone in cerebellum peaked within 10 minutes following injection and then rapidly dropped. The association rate constant "k3" was calculated from the slope of the radioactivity-ratio of striatum to cerebellum versus the equivalent time. The equivalent time was calculated from the radioactivity of cerebellum as an input function. The exponential decrease of the k3 value with aging was observed. The k3 value of the youngest subject (22 years old, male) was 0.035/min, while that of the oldest one (72 years old, male) was found to be 0.020/min. These data suggested that the dopaminergic activity through D2 dopamine receptors reduces with aging in human striatum.  相似文献   
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