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101.
Summary In a cross-sectional study on 236 individuals in Japan (174 males, 62 females; 149 smokers, 87 non-smokers) plasma nicotine (pnic), cotinine (pcot) and thiocyanate (pSCN), urinary creatinine ratios of nicotine (unic), cotinine (ucot) and thiocyanate (uSCN) as well as carboxyhemoglobin (COHb) and expired carbon monoxide (COex) were determined. All tobacco smoke uptake parameters (TSUP) were significantly elevated in smokers as compared to non-smokers. The discriminant power (smokers vs non-smokers) rank in the following order: ucot pcot unic > pSCN COHb pnic > COex uSCN. All parameters except for pnic are significantly correlated with the self-reported number of cigarettes smoked per day. The reason for the poor correlation of pnic with daily cigarette consumption is the short half-life of pnic coupled with the arbitrary time of blood drawing in relation to the last time of smoking.Dr. Muranaka, the chief author of this paper, was the director of our hospital. He died suddenly on 18 April 1986. This article is therefore the last monument to be planned and achieved under the late Dr. Muranaka's direction.  相似文献   
102.
Nineteen patients with typical osteosarcoma were studied for evidence of association with human leukocyte antigen (HLA) phenotypes. HLA-A11 was detected in nine of 19 patients (47.4%) compared with 16.9% of 235 controls (chi 2 " 10.861, p less than 0.001), which yielded an odds ratio of 4.523. The positive rate of HLA-A11 was significantly increased in the patients. Interestingly, five of seven patients with poor prognosis had HLA-A11, compared with two of nine disease-free patients, 18 months after the initial treatment. These data suggest that major histocompatibility complex (MHC)-linked genes determines susceptibility to the occurrence of osteosarcoma and its prognosis.  相似文献   
103.
Thirty-two cases of congenital arachnoid cyst (AC), 26 cases of supratentorial, and 6 cases of infratentorial cyst are reported. They were encountered over a period of 9 years. The 26 supratentorial cysts consisted of 21 cases located in the middle fossa, 2 in the frontal, and 3 in the suprasellar. Patients' ages ranged from 7 months to 67 years (mean: 19.3 years), with a male to female ratio of 23:9. The most common symptoms were headache, epileptic seizure, and cranial enlargement. Based on observations between neuroradiological examinations including analysis of the cyst content, and operation, typical AC might be defined as "duplicated arachnoid and its splitting", and it may be said that "there is continuous existence of cerebral structure such as cortex and white matter lying adjacent to AC on MRI". Out of 32 cases, 15 received surgical treatment because of mass effect of AC itself, abnormal dynamics of the AC fluid, and/or increasing sign of ICP. 13 cases had resection of AC outer membrane with craniotomy, and the remaining two had cystoperitoneal shunt. One of the shunting cases complicated subdural hematoma. Surgical treatment was discussed and radical craniotomy rather than a shunt procedure was preferred. Prognosis of all cases was favorable and uneventful.  相似文献   
104.
Transient induction of single GST-P positive hepatocytes by DEN   总被引:12,自引:3,他引:9  
The single cells positive for placental glutathione S-transferase(GST-P), detectable in livers of rats soon after treatment withhepatocarcinogens, are possible ‘initiated cells’,the hypothesis tested in the present series of experiments.No low dose threshold was observed in male Sprague-Dawley ratsat different single doses of diethylnitrosamine (DEM) althougha plateau was reached between 160 and 200 mg/kg body weight.At the latter single dose 12 400 positive cells/cm3 were observedimmunohistochemically in rat livers after one week, the numbersthen decreasing to week 8 and thereafter rising again. In thenumbers then decreasing to week 8 and thereafter rising again.In the early stages single cells predominated but with timea gradual increase in mini-foci and larger lesions became evident.Application of selection pressure (feeding of diet containing0.02% 2-AAF plus partial hepatectomy) to rats 2–24 weeksafter single DEN-treatment resulted in the formation of largefoci positive for GST-P, especially in the early stages, thegrowth response being less pronounced with time. The numberof foci, on the other hand. was correlated with the number offoci, on the other hand, was correlated with the number ofsingle cells/mini-foci detected inhepatectomy tissue of thesame individuals. These results suggest that the early GST-Ppositive populations could be the precursor for preneoplasticfoci and nodules.  相似文献   
105.
It is known that benzodiazepines have a hypotensive effect, but the mechanism has not been well elucidated yet. To clarify whether this effect is due to central or peripheral mechanism, we administered 5 mg of diazepam or saline intravenously to healthy volunteers and assessed the change in blood pressure, heart rate, muscle sympathetic nerve activity and heart rate variability. After diazepam administration, systolic and mean blood pressure decreased significantly. Muscle sympathetic nerve activity was also significantly reduced but heart rate did not change, whereas the variables of spectral analysis of heart rate variability did not show significant change. We concluded that the hypotensive effect of diazepam in human is mainly due to the central mechanism.  相似文献   
106.
Bruch's membrane exists between the retinal pigment epithelium and the choriocapillary endothelium. Its structure is very complicated, having five sublayers containing basement membranes of retinal pigment epithelium and choriocapillary endothelium, outer and inner collagenous layers, and a central elastic layer. In the development of Bruch's membrane in normal mice, both basement membranes are created first. Secondarily, collagen fibers are accumulated in the space between these basement membranes and then form a collagenous layer. Finally, the elastic layer elaborated in the collagenous layer separates this into outer and inner collagenous layers. Brachymorphic mice have a disorder in the sulfation pathway, resulting in undersulfation. Consequently, in Bruch's membrane of brachymorphic mice, the expression of decorin, a small proteoglycan containing chondroitin sulfate and an indispensable component in collagen assembly, is at a very low level. It is clear that hypoplasia of the collagenous layer in Bruch's membrane of brachymorphic mice induces a disorder in the following formation of the elastic layer. These findings suggest that the formation of the collagenous layer, regulated with acidic glycoconjugates such as decorin, is important in the development of Bruch's membrane.  相似文献   
107.
Perforin-dependent killing of tumor cells by Vgamma1Vdelta1-bearing T-cells   总被引:1,自引:0,他引:1  
The T-cell subset expressing Vdelta2 paired primarily with Vgamma2 comprises a majority of gammadelta T-cells in human adult peripheral blood and expands significantly during a variety of infectious diseases. In contrast, the other subset of gammadelta T-cells that express Vdelta1 is rare among circulating T-cells and its function is poorly understood. Here, we show that a Vgamma1Vdelta1(+) T-cell line, 3-D, established from human peripheral blood by immortalization with Herpesvirus saimiri was able to specifically recognize tumor cells, such as K562 cells, and release cytotoxic granules containing perforin for target cell killing. Some tumor cells, including Daudi cells that are known to be susceptible to killing by Vdelta2(+) T-cells, were resistant to 3-D killing, implicating distinct pathways for tumor cell control by Vdelta1(+) and Vdelta2(+) T-cells. The 3-D T-cell receptor (TCR):CD3 complex reconstituted in TCR-deficient Jurkat cells was capable of transmitting signals, evidenced by activation of the interleukin 2 (IL-2) gene following ligation with anti-CD3 antibody, yet the TCR-reconstituted cells failed to produce IL-2 in response to the target cells. Thus, these results raise the possibility that some Vgamma1Vdelta1(+) T-cells could potentially be stimulated and lyse tumor cells via ligation of TCR/CD3-unassociated molecules.  相似文献   
108.
109.
A type C RNA virus was isolated from mink lung cell line (American Type Culture Collection No. CCL 64) which had been cocultivated with 5-bromodeoxyuridine (BUDR)-treated mouse spleen cells. The virus has type C RNA virus morphology as demonstrated by electron microscopy. The complement fixation and immunofluorescent tests performed with mouse anti-p30 antisera show a distinctive difference between mink and mouse type C viruses. Complement fixation tests also indicate that mink type C virus is antigenically different from rat, feline leukemia, feline endogenous (RD-114), baboon, and woolly monkey type C viruses. The virus propagates in cells of mouse, rat, cat, sheep, dog, and human origin, but not in bovine (MDBK) or simian (BSC-1) cells. The infection of rabbit (SIRC) cells and cells of virus origin (mink lung) was followed by delayed and low-titer polymerase release in tissue culture media. The virus sediments in sucrose density gradients as a broad band of densities, 1.13–1.17 g/ml, and contains 70 and 4S RNA. The protein profile is similar to that observed in other mammalian type C viruses. The DNA complementary to the poly(A)-containing virion RNA hybridized to a high degree (72%) with the RNA from virus-producing mink lung cells but not with the RNA from mouse cell lines or uninfected mink lung cell line. The nucleotide sequences homologous to mink viral cDNA were found in mink cell DNA from both virus-producing and nonproducing cells, but not in the DNA of mouse, rat, or feline origin. The virus here described therefore represents an endogenous mink type C virus.  相似文献   
110.
To demonstrate ultrastructural events in the early phase of hepatic metastasis of human colon carcinoma, we intrasplenically injected a highly metastasizable, human colon carcinoma cell line LM-H3 (1 x 10(6) cells) into nude mice, and electron microscopically investigated the hepatic metastasis. At 24 h, tumor cells adhered to the endothelial wall of terminal portal venules and periportal sinusoids. At 48-72 h, after extravasation, they deeply invaded the hepatic cell plate and the interstitial tissue of the portal tract, in which they underwent proliferation and made the metastatic foci. Tumor cells were linked with each other or with surrounding hepatocytes by desmosomes. Desmosomes were maintained during the mitosis. When invading tumor cells were exposed to the bile canaliculi, they generated microvilli on the surface. Microvilli were also formed at the luminal surface of intracytoplasmic inclusions. In the interstitial tissue of the portal tract, tumor cells were closely associated with fibroblasts. However, no junctional specializations were seen between them. The present study demonstrated that human colon carcinoma cell line LM-H3 formed desmosomes with hepatocytes soon after invasion of the hepatic cell plate, suggesting the regulatory role of an interaction with hepatocytes in the growth of metastatic foci within the liver parenchyma.  相似文献   
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