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71.
The chemical and radio toxicity of 125-5-iodo-2-deoxyuridine (125IUDR) on 870127T human lung cancer (HLC) cells grown in tissue cultures and the quantitative analysis of the distribution and fate of 125IUDR-labeled 870127T HLC cells in nude mice were evaluated. After 870127T HLC cells were plated and 125IUDR was added to the dishes at levels ranging from 0.1 µCi/ml to 5.0 µCi/ml of media, the growth rate of the cells for 24h was similar to that of non-labeled cells. Nude mice were given intravenous injections of 125IUDR labeled 870127T HLC cells and killed at various intervals ranging from 5 min to 24 h after injection. Organs were collected, processed, and monitored. The lung contained most of the tumor cells at all intervals and the number of tumor cells in the lung decreased gradually post-injection. The tumor cells died rapidly, and only about 1.5% of all cell survived after 24 h post-injection. This study confirmed that very few surviving tumor cells are needed to cause metastasis. 相似文献
72.
Objectives It is likely that genetic factors play a role in the etiology of chronic sinusitis, and airway inflammation is an important pathological feature in chronic sinusitis. We hypothesized that individuals with greater inflammatory responses may be more likely to acquire the disease. Polymorphisms of the tumor necrosis factor (TNF) genes have been described, and certain inflammatory diseases are reportedly associated with certain alleles of TNF genes. The purpose of this study is to examine whether there is an association between some alleles of TNF genes and chronic sinusitis. Study Design Thirty‐eight Japanese patients with intractable chronic sinusitis were selected on the basis of the following criteria: 1) persistent mucous or mucopurulent nasal discharge and/or postnasal dripping for longer than 3 years and 2) opacification in bilateral maxillary sinuses and ethmoid cells on plain radiographic films. Methods Both tumor necrosis factor‐α (TNF‐α) and tumor necrosis factor‐β (TNF‐β) gene polymorphisms were analyzed by polymerase chain reaction (PCR) with restriction fragment length polymorphisms in these patients and 35 healthy control subjects. Results A significantly higher frequency (P < .05) of TNFB*2 allele of TNF‐β gene polymorphism was observed in patients with chronic sinusitis (74%) compared with control subjects (56%). There was no association between alleles of TNF‐α and chronic sinusitis. Conclusion We concluded that TNF‐β gene polymorphism may form a component of the genetic predisposition to chronic sinusitis in Japanese patients. 相似文献
73.
The role of an operating microscope in medico-legal practice 总被引:1,自引:0,他引:1
This article describes our experience in the use of a binocular surgical microscope at autopsy for the in situ forensic examination of various types of mechanical skin wounds. The microscopic image was visualised on a closed-circuit television monitor, and colour photographs and video recordings were simultaneously obtained from the monitor. With abrasions, small epidermal tags, which play a key role in the determination of external force direction, were clearly observed. With lacerations, crushing of the epidermis was observed at the wound margin, and continuous bridges of connective tissue and/or blood vessels were also found within the wound cavity. With incised wounds, the epidermis was intact up to the wound margin, and there was no continuous bridge within the wound cavity. Using these differences, it was, therefore, simple to distinguish lacerations from incised wounds. Ligature marks due to hanging were clearly observed, with petechial haemorrhages and minute abrasions readily seen in the lesion. For stab wounds caused by a single-edge knife, the morphological difference between the two ends of the wound caused by the sharp blade and the blunt side could be distinguished. It was also possible to confirm the identification of unknown cadavers by observing old wound scars using the operating microscope. Abnormal lesions of the blood vessels, such as a mechanical tear of the vertebral artery (the origin of a subarachnoid haemorrhage) and the atherosclerotic stenosis of the coronary artery, were detectable. In addition, the microscope was useful as a teaching aid to colleagues and medical students to study the nature of the wounds during or after the autopsy. We believe that this system presents advantages in terms of education and training of forensic pathologists and physicians as well as crime investigation officers. 相似文献
74.
Hibi M Yoshida K Ohshima H Tomida Y Murakami F Matsuura A Kawamura M 《Kyobu geka. The Japanese journal of thoracic surgery》1999,52(1):79-81
It has been pointed out in general that the resistance against infection is decreased in the diabetic patients. This problem is very important in patients undergoing major surgery. In cardiovascular surgery, the median wound infection may result in life threatening sequelae. We have used the internal thoracic artery as the appropriate graft for its excellent long-term patency. In this series of the diabetic patients who underwent coronary artery bypass grafting with bilateral internal thoracic artery grafts, the incidence of postoperative mediastinitis was significantly higher than other cases. Therefore the use of bilateral internal thoracic artery grafts should be avoided, if possible in the diabetic patients. 相似文献
75.
Yoshimura N Yamaguchi M Ohshima Y Oka S Ohtaki Y Murakami H Hasegawa T Shimazu C Ogawa K Tei T Kuroe K Kido S 《Kyobu geka. The Japanese journal of thoracic surgery》1999,52(4):286-289
From 1989, 4 patients underwent bilateral enlargement of the aortic valve ring for valve replacement. Age at the operation ranged from 2 to 8 (mean 6) years; body weight ranged from 14.9 to 25.4 (mean 19.0) kg. This procedure enabled us to implant a prosthesis 3 to 4 sizes larger (19 to 23 mm) than that measured with the native aortic annulus (13 to 17 mm). There was no late death and no cardiac event over a mean follow-up period of 6.2 years. Pressure gradient across the prosthesis measured by echocardiography was 40 mmHg in 1 patient who underwent aortic valve replacement with the use of 19 mm St. Jude Medical valve at 2 years of age. There was no significant pressure gradient in other 3 patients. All patients showed normal left ventricular function. We conclude that bilateral enlargement of the aortic valve ring for valve replacement has provided good midterm results with no mortality and no cardiac event. 相似文献
76.
Shohei Nakamura Yutaka Kobayashi Kazuhiko Tozuka Akihiko Tokue Akira Kimura Chikuma Hamada 《The Journal of urology》1996,156(4):1275-1279
Purpose
Circadian changes in urinary frequency, diuresis and bladder capacity were evaluated in middle-aged and elderly patients.Materials and Methods
A total of 2,703 urinations from 50 men (median age 66 years) was recorded with a 24-hour uroflowmetry system.Results
During a 24-hour period the elderly group showed increased frequency and decreased bladder capacity. No difference was observed in diuresis between the 2 age groups. From midnight to 6 a.m. frequency in the elderly group was significantly greater (p less than 0.01) than that in the middle-aged group.Conclusions
Increased frequency in the elderly group during these hours was primarily due to an increase in diuresis. 相似文献77.
Tohru Ide Tetsuo Kochi Kazuhiko Iijima Tadanobu Mizuguchi 《Journal canadien d'anesthésie》1996,43(1):44-49
Purpose
The purpose of this study was to determine the effect of increasing the concentrations of sévoflurane anaesthesia on the distribution of diaphragm blood flow (Qdi) in ten dogs during mechanical ventilation.Methods
Animals were divided into two groups, sévoflurane (n = 6) and time control (n = 4) groups. Blood flow to the crural and the costal diaphragm (Qcru, Qcost) was determined by the hydrogen clearance technique at 0, 0.5, 1.0 and 1.5 minimum alveolar concentration (MAC) of sévoflurane after a 30 min period of steady-state conditions. Cardiac output (CO) and the mean arterial blood pressure (MBP) were also measured.Results
Sevoflurane anaesthesia caused a reduction in CO (L · min?1) from a control value of 1.51 ± 0.21 to 1.38 ±0.1 (0.5 MAC), 1.09 ± 0.15 (1.0 MAC) and 0.98 ± 0.12 (1.5 MAC) (Mean ± SD). Mean blood pressure, Qcru and Qcost also decreased with increasing depth of anaesthesia. In addition, the decrease of Qcru was greater than that of Qcost at all levels of MBP and CO. No change occurred in these variables in the lime control group.Conclusion
Sevoflurane anaesthesia changes the distribution of Qdi with a greater reduction occurring in Qcru than in Qcost. 相似文献78.
Penetration of etoposide into human malignant brain tumors after intravenous and oral administration
Katsuzo Kiya Tohru Uozumi Hidenori Ogasawara Kazuhiko Sugiyama Takuhiro Hotta Takashi Mikami Kaoru Kurisu 《Cancer chemotherapy and pharmacology》1992,29(5):339-342
Summary Penetration of etoposide into the cerebrospinal fluid, brain tumor, and brain tissue after intravenous administration was investigated in patients presenting with malignant brain tumors. A relatively low dose (55–65 mg/m2) was used to compare intravenous with oral administration. High-performance liquid chromatography with fluorescence detection was used to evaluate drug levels. Plasma and cerebrospinal fluid levels of etoposide after oral administration (50–150 mg/day) were also studied so as to determine the adequate oral dose for the treatment of malignant brain tumors. The peak plasma concentration after intravenous administration ranged from 7.01 to 10.47 g/ml, varying in proportion to the injected dose, whereas that after oral administration was lower, namely, 1.44–4.99 g/ml, and was unstable when the oral dose was 150 mg daily. The peak cerebrospinal fluid level following either intravenous or oral administration was much lower than the plasma concentration and was influenced by the peak plasma level and the sampling site. The etoposide concentration in cerebrospinal fluid taken from the subarachnoid space and ventricle of patients displaying no tumor invasion and of those presenting with meningeal carcinomatosis and in cerebrospinal fluid taken from the dead space after tumor resection was 0.7%±0.5%, 3.4%±1.0%, and 7.2% ± 8.5%, respectively, of the plasma concentration. Serial oral administration did not result in the accumulation of etoposide in cerebrospinal fluid. The tumor concentration (1.04–4.80 g/g) was 14.0%±2.9% of the plasma level after intravenous administration, was related to the injected dose, and was approximately twice the concentration detected in the brain tissue. Therefore, a relatively low dose of etoposide injected intravenously penetrates the brain tumor at an efficacious concentration. Our results indicate than an oral dose of 100 mg etoposide be given for malignant brain tumors, as limited penetration of the drug into the intracranial region was observed. 相似文献
79.
Fernando Santos James C. M. Chan James D. Hanna Kazuhiko Niimi Richard J. Krieg Jr Martha D. Wellons 《Pediatric nephrology (Berlin, Germany)》1992,6(3):262-266
To investigate the effects of growth hormone (GH) on the reversal of growth failure in uremia, recombinant human GH (rhGH) was administered to rats with chronic renal failure (CRF). The dosage of rhGH was 3 IU/day (i.p.) for 13 days after the induction of CRF by 5/6 nephrectomy. Animals were classified into four groups: untreated nephrectomized rats (NX,n=40), GH-treated nephrectomized rats (NX+GH,n=18), sham-operated rats fed ad libitum (SHAMAL,n=27), and sham-operated rats pair-fed with 10 NX rats (SHAMPF,n=10). NX and NX+GH rats developed a similar and moderate degree of CRF, serum urea nitrogen being (mean±SEM) 49±3 and 54±4 mg/dl, respectively, compared with 16±4 and 19±0 mg/dl in SHAMAL and SHAMPF groups. Weight (56.0±3.3 g) and length (3.5±0.1 cm) gains of NX rats were lower than those of SHAMAL rats (94.2±4.0 g,P<-0.0001 and 4.1±0.2 cm,P<-0.01). Growth of the SHAMPF group and the matched NX rats was not significantly different. Weight (56.2±5.0 g) and length (3.4±0.2 cm) gains of NX+GH and NX rats were similar, the beneficial effect of GH therapy on growth being observed in only those animals with more severe degrees of uremia. This growth-promoting action resulted from greater food efficiency and not from stimulated food intake. The hypercholesterolemia seen in NX rats, 81±2 mg/dl versus 55±3 mg/dl in SHAMAL (P0.0001), was not increased in the NX+GH group, 87±3 mg/dl. There was a positive and significant correlation between serum cholesterol and serum urea nitrogen values in NX and NX+GH animals. This study suggests that growth impairment of mild CRF is mainly due to malnutrition and is refractory to GH administration. GH therapy improves the growth rate of animals with advanced CRF without aggravating their lipid abnormalities. 相似文献
80.