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11.
Human gastric carcinoma cells from one of three long-term cultured cell lines (HPE-GAC-T) were injected into peritoneal cavities of BALB/c mice. The surviving celss in vivo were collected 3 days later. Following brief cultivation in vitro, those cells were reinjected into mice by the same route. This procedure was repeated 3 times. The cultured cancer cells recovered from the mice on the 3rd passage, at a 92.5% recovery rate, showed xenotransplantability in BALB/C nu/nu mice by subcutaneous injection. This subline (GAC-T.M-2) can be maintained in vitro but not in vivo while maintaining heterotransplantability. Three original cancer cell lines did not show tumorigenicity in nude mice. Animal passages by the same protocol failed to select tumorigenic sublines from the other cell lines (HPE-GAC-2 and -3). Factors affecting tumorigenic capacity of cancer cells in nude mice were studied in vivo and in vitro by comparing the properties of GAC-T.M-2 and parental cancer cells (GAC-T.O). Treatment of the hosts by injection of anti-asialoGM1 antibody or cyclophosphamide, adult thymectomy of BALB/c mice, and 400 rads whole body irradiation did not enhance the growth of either GAC-T.M-2 or -T.O cells. There was no detectable difference between in vitro growth properties of the original and variant cells at a rather high cell density. However, at a low cell density GAC-T.M-2 cells showed a higher cell growth rate and increased [3H] thymidine incorporation and possessed higher colony forming activity in the liquid medium than their parental cells. High dense expression of epidermal growth factor (EGF) receptors was evident equally in both GAC-T cells, however, GAC-T.M-2 cells were more sensitive to down-regulation by EGF in culture. Tumor cells of HPE-GAC-2 and -3 lines expressed minimum amount of EGF receptors on their cell surfaces and were refractory to additional EGF in culture. The results indicate that growth factors and their receptors are responsible for tumorigenicity in nude mice.  相似文献   
12.
A 47-year-old male visited our hospital complaining of painless swelling of the right scrotum. Ultrasonography demonstrated hydrocele and a 13 x 12 x 10 mm cystic space along the margin of the right testis. Hydrocelectomy and simple resection of the cyst were performed. Pathologic examination of the excised cyst showed a serous cyst lined with simple flattened epithelium. Ultrasonography is useful for the diagnosis of tunica albuginea cyst.  相似文献   
13.
Thoracoscopic surgery for lung cancer.   总被引:1,自引:0,他引:1  
Thoracoscopic surgery has raised awareness in minimizing invasiveness in respiratory surgery. In the case of lung cancer, technical difficulties associated with standard curative surgery may not allow the use of a total thoracoscopic procedure. Although thoracoscopic lung cancer surgery is minimally invasive and safe, it demands a high level of skill and care. Surgery is often performed using a small incision and direct vision, with the thoracoscope serving as a light source. However, thoracoscopic surgery is expected to progress further in the near future. In addition, a new surgical system that comprehends both open and video-assisted thoracic surgery (VATS) may gain popularity.  相似文献   
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15.
The effect of ganglioside on diabetic neurogenic bladder   总被引:1,自引:0,他引:1  
The effect of ganglioside was studied in 6 diabetic patients with neurogenic bladder. Ganglioside is glycosphingolipids which seems to be involved in the processes of nerve growth, regeneration and tissue reinnervation. The treatment consisted in the daily intramuscular administration of 20 mg ganglioside. Clinical symptoms, vibration sensation and urodynamic studies were recorded at the beginning and 4 weeks later. The clinical responses assessed by subjective complaints and vibration sensation were effective, but no statistically significant difference in urodynamic studies was obtained. Side effects were not observed. In conclusion, ganglioside treatment seems to have a positive effect on diabetic neurogenic bladder.  相似文献   
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17.
Previous studies have suggested that facial displays in the presence of others are influenced by the relationship with accompanying persons. In these studies, subjects participated with friends or strangers, without any focus on social interactions between partners. In the current study, pairs of friends or strangers viewed film clips expected to elicit positive and negative affects; the control group participated without partners. We measured synchronous smiles between partners as a social interactive display, in addition to the duration and the frequency of smiles and frowns. Subjective emotion and social motive were also measured. Smiles were facilitated by the presence of a friend than a stranger or the condition of lone participation, regardless of stimulus valence. Synchronous smiles and the communication motive were also enhanced with a friend than with a stranger. These results suggested that the expression of smiles was facilitated by the communication motive and social interactions between partners.  相似文献   
18.
BACKGROUND: Exposure to acute stressors modulates both innate and acquired immune function. However, little is known about whether stress has the potential to modulate the pathogenesis of allergic rhinitis. OBJECTIVES: To determine the effects of acute restraint stress on the initiation of allergic rhinitis in a murine model. METHODS: CBA/J mice were repeatedly intranasally sensitized with phospholipase A2 (PLA2) from honeybee venom without adjuvant. Restraint stress was applied using uniform cylinders once a week for a continuous 8-hour period, on five occasions in total. Production of PLA2-specific antibodies and degree of nasal and blood eosinophilia were compared between stressed and control mice. RESULTS: Repeated intranasal sensitization with PLA2 induced PLA2-specific IgE and marked eosinophilia in both the nose and blood in CBA/J mice. Exposure to restraint stress significantly inhibited production of PLA2-specific IgE, IgG1 and IgG2a. Conversely, the stress exerted no significant effect on eosinophilia. CONCLUSIONS: Exposure to acute restraint stress inhibits antigen-specific antibody production, but not local or systemic eosinophilia. The results of this study suggest that acute stress has the potential to modulate the initiation of allergic rhinitis.  相似文献   
19.
Two cell lines designated IC KMS and D KMS were established from human adenovirus type 12 induced tumors of C3Hf/OK mouse. The cell lines retained the characteristics of the original tumor i.e., production of numerous C type and intracisternal A-type particles, integration of Adl2 El region DNA and amplification of the myc gene family. Chromosomal analysis revealed chromosome aberrations in both IC KMS and D KMS cells. The modal chromosome number of IC KMS cells was 54 and that of D-KMS cells was 48. Metacentric chromosomes and mini-chromosomes were found. Trisomy of chromosome 3, 7 and 12 was seen frequently in D KMS cells. Although DNA aneuploidy was revealed by flow cytometry, the DNA indices of these cells showed no relation to the copy number of integrated Adl2 DNA. These cells have been propagated by serial culture during the past 17 months. Production of endogenous virus particles is a unique characteristic of IC KMS and D KMS cells. These cell lines would be useful materials for examining the contribution of Adl2 carcinogenesis to activation of endogenous virus particles, and also the correlation between Adl2 carcinogenesis and cancer related genes. Acta Pathol Jpn 42: 242-248, 1992.  相似文献   
20.
Point of care testing(POCT) is defined as clinical testing done at or near the site of patient treatment and care in the medical field, and includes all clinical test other than those performed at hospital laboratories and outside testing centers. Home testing is also a form of POCT relating to residential medical care. The ratio of clinical tests based on POCT has not tended to increase as rapidly in Japan, although such tests are greatly increasing in the US while clinical tests performed at hospital laboratories are decreasing. POCT products are generally applied to direct analysis of test samples obtained from patients. Since storage, transportation or pretreatment after sampling is not necessary in POCT, test data can be obtained in real time. Therefore, it is important to complete testing immediately after obtaining samples without transporting or storing them, when handling POCT samples. Consideration of POCT as a part of health care services covered by health insurance is the same as in the case of conventional testing. Recent technological innovation has provided a wide variety of POCT products that do not require medical equipment or reagents. Further development of novel, innovative POCT procedures in the near future is promising.  相似文献   
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