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31.
Somatic Mutation in Human B-Cell Tumors   总被引:15,自引:0,他引:15  
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32.
To evaluate the presence of Epstein–Barr virus (EBV) in lung cancers of Japanese patients, 81 lung cancers were examined using a highly sensitive in situ hybridization (ISH) method, employing an antisense oligonucleotide probe for EBV-encoded small nuclear RNA-1 (EBER). EBER1 expression was demonstrated in one poorly differentiated squamous cell carcinoma associated with marked lymphoid stroma (PDSCC-LS), two well differentiated adenocarcinomas, and two moderately differentiated squamous cell carcinomas, but was not detectable in other lung cancers, including small cell carcinomas. Unlike lymphoepithelioma-like undifferentiated carcinoma (LELC) of the lung, the PDSCC-LS consisted of poorly differentiated cells with distinct cell borders and nuclei with a coarse chromatin pattern and some prominent nucleoli. Most of the cancer cells expressed intense EBER1 signals. Although small to moderate numbers of cells positive for EBER1 were present in two adenocarcinomas and two squamous cell carcinomas, EBER1 signals varied in intensity and number in these four cases. Although polymerase chain reaction (PCR) and Southern blot hybridization with a 32P-labelled probe internal to the primers were conducted to detect the EBV genome in 24 lung cancers, including five EBER1-positive cases, the genome was found to be positive in the five cases with EBER1-positive staining, including the PDSCC-LS, two adenocarcinomas and two squamous cell carcinomas, but not in the other cases. This study indicates that the morphological features of EBV-associated lung cancers are not restricted to the typical LELC type.  相似文献   
33.
To investigate whether the rate of change in blood pressure affects the sensitivity of the aortic baroreceptor afferent response, the change in aortic nerve activity (ANA) to two different rates of ramp increase in mean blood pressure (MBP), elicited by phenylephrine administration, was determined in the rat under urethane (1.5 g kg−1) anesthesia. The sensitivity of the increase in ANA following a rapid (average ramp rate, 9.14 ± 0.60 mmHg s−1, n = 11) or gradual (1.78 ± 0.24 mmHg s−1, n = 11) increase in MBP was 2.03 ± 0.14% and 1.81 ± 0.20% of baseline mmHg−1, respectively. These values were not significantly different from each other (P = 0.16). Furthermore, we found no correlation between the rate of ramp increase in MBP and the sensitivity of the increase in ANA (r = 0.24, P = 0.29, n = 22). These results suggest that, at least within the normal physiological range of MBP, the rate of the ramp change in blood pressure does not affect aortic baroreceptor afferent sensitivity in the anesthetized rat.  相似文献   
34.
Differentiated gastric carcinoma (DGC) corresponds roughly to the intestinal type of gastric carcinoma described by Laurén. It has been suggested that DGCs arise from intestinalized gastric mucosa, but recent findings regarding their mucin expression do not support this hypothesis. To evaluate the histogenetic relationship between DGCs and intestinal metaplasia, lesions that are as small as possible should be examined. Twenty-five DGCs, ranging in their greatest dimension from 0.4 to 2.7 mm, were collected and divided into two groups by size. Group A consisted of 13 lesions less than 1.4 mm across, and group B of 12 lesions 1.4 mm or more. The presence of mucin and a brush border was assessed by immunostaining with antibodies against human gastric mucin, pyloric-gland-type mucin, Muc-2 glycoprotein, and CD10 antigen, and the lesions were classified as having the gastric phenotype (G-type), intestinal phenotype (I-type), mixed gastric and intestinal phenotype (M-type), or null phenotype (N-type). Thirteen (52%) of the 25 lesions were N-type, 5 (20%) lesions were G-type, 5 (20%) were I-type, and 2 (8%) were M-type. Group A had a larger proportion of N-type lesions than B (10/13, or 77%, vs. 3/12, or 25%; p = 0.027, chi-square test for proportions). Group B had a larger proportion of G-type lesions than A (5/12, or 42%, vs. 0/13, or 0%; p = 0.033). The phenotypes of the carcinomas and their surrounding mucosa were unrelated. Therefore, DGCs may arise from gastric mucosa affected by intestinal metaplasia or not, without having either the gastric or intestinal phenotype.  相似文献   
35.
Osteopenia/osteoporosis and sarcopenia are common geriatric diseases among older adults and harm activities of daily living (ADL) and quality of life (QOL). Osteosarcopenia is a unique syndrome that is a concomitant of both osteopenia/osteoporosis and sarcopenia. This review aimed to summarize the related factors and clinical outcomes of osteosarcopenia to facilitate understanding, evaluation, prevention, treatment, and further research on osteosarcopenia. We searched the literature to include meta-analyses, reviews, and clinical trials. The prevalence of osteosarcopenia among community-dwelling older adults is significantly higher in female (up to 64.3%) compared to male (8–11%). Osteosarcopenia is a risk factor for death, fractures, and falls based on longitudinal studies. However, the associations between osteosarcopenia and many other factors have been derived based on cross-sectional studies, so the causal relationship is not clear. Few studies of osteosarcopenia in hospitals have been conducted. Osteosarcopenia is a new concept and has not yet been fully researched its relationship to clinical outcomes. Longitudinal studies and high-quality interventional studies are warranted in the future.  相似文献   
36.
The effects of exercise on nutrient digestion and absorption in the intestinal tract are not well understood. A few studies have reported that exercise training increases the expression of molecules involved in carbohydrate digestion and absorption. Exercise was also shown to increase the blood concentration of glucagon-like peptide-2 (GLP-2), which regulates carbohydrate digestion and absorption in the small intestine. Therefore, we investigated the effects of exercise on the expression of molecules involved in intestinal digestion and absorption, including GLP-2. Six-week-old male mice were divided into a sedentary (SED) and low-intensity exercise (LEx) group. LEx mice were required to run on a treadmill (12.5 m/min, 1 h), whereas SED mice rested. All mice were euthanized 1 h after exercise or rest, and plasma, jejunum, ileum, and colon samples were collected, followed by analysis via IHC, EIA, and immunoblotting. The levels of plasma GLP-2 and the jejunum expression of the GLP-2 receptor, sucrase-isomaltase (SI), and glucose transporter 2 (GLUT2) were higher in LEx mice. Thus, we showed that acute low-intensity exercise affects the expression of molecules involved in intestinal carbohydrate digestion and absorption via GLP-2. Our results suggest that exercise might be beneficial for small intestine function in individuals with intestinal frailty.  相似文献   
37.

This study aimed to evaluate the efficacy and safety of excimer laser coronary atherectomy (ELCA) prior to paclitaxel-coated balloon angioplasty for de novo coronary artery lesions. This retrospective observational study analyzed 118 eligible patients with de novo coronary artery disease whose only percutaneous coronary intervention was a drug-coated balloon angioplasty (i.e., no subsequent stent placement). Data related to our primary outcomes of interest—incidence of major adverse cardiovascular and cerebral events (MACCE), and incidence of procedural complications (bailout stenting and minor complications)—were collected and retrospectively analyzed. ELCA was used significantly more often in the cases of main branch and ostial lesions (i.e., of the circumflex, right coronary, or left anterior descending arteries, or high lateral branch), normally associated with poor treatment outcomes (55.6% vs. 14.3%, p < 0.0005). However, the two groups were not different in terms of cumulative incidence as estimated by the Kaplan–Meier method (log-rank test, p = 0.603) and a causal relationship between ELCA and MACCE was not identified (OR, 2.223; 95% CI, 0.614–8.047; p = 0.223). This study confirms the safety of ELCA prior to paclitaxel DCB angioplasty to treat de novo coronary artery lesions. While difficult-to-treat lesions were significantly more prevalent in the group treated by ELCA, the study revealed similar efficiency as conventional pre-dilation methods. Our findings provide grounds for a prospective randomized trial with consistent lesion and procedural characteristics to evaluate the potential benefits of combining paclitaxel DCB angioplasty following ELCA for de novo coronary artery lesions.

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38.
39.
Blood samples and 24-h duplicates of food were collected in the years around 1980 and then in 1990's from inhabitants of nonpolluted regions in Japan. The 1990 study is still in progress with 286 blood samples and 125 food duplicates already collected from 7 regions. A preliminary analysis is made in the present study with the data obtained from the 7 study regions where the survey was conducted in 1980 and then in 1990, to examine possible changes in dietary cadmium intake (Cd-D) and consequently cadmium levels in blood (Cd-B) during this 10 year period. The food duplicate analysis showed that Cd-D in 1980 was 47.1 g/day (1.74):65 [GM (GSD):N] for men and 27.7 g/day (1.75):65 for women. The counterpart values in 1990 were 29.5 g/day (1.66):40 for men and 23.8 g/day (1.73):85 for women; the difference between the two values for the same sex is significant (P<0.05) both=" in=" men=" and=" in=" women,=" suggesting=" that=" there=" occurred=" about=" 37%=" and=" 14%=" reduction=" in=" dietary=" cadmium=" intake=" during=" this=" 10=" year=" period=" in=" men=" and=" in=" women,=" respectively.=" comparison=" in=" cd-b=" showed=" that=" cd-b=" for=" men=" and=" women=" in=" 1990=" were=" 1.79=">g/l (2.01):121 and 1.84 g/l; (1.67):165, respectively, whereas the counterpart values in 1980 were 3.84 g/l (1.64):123 and 3.57 g/l (1.42):141, respectively, indicating significant (P<0.01) reduction=" in=" cd-b=" in=" both=" sexes=" in=" parallel=" to=" the=" reduction=" in=" cd-d.=" the=" role=" of=" rice=" as=" a=" major=" source=" of=" cadmium=" among=" japanese=" population=" together=" with=" recent=" reduction=" in=" the=" importance=" is=" discussed;=" cd=" in=" rice=" accounted=" for=" 72%=" in=" late=" 1970's,=" whereas=" it=" is=" about=" 35%=" in=" the=" present=">  相似文献   
40.
Summary The inhibitory effect of a new dihydropyridine derivative, (±)-2-[benzyl(phenyl)amino]ethyl-1,4-dihydro-2,6-dimethyl-5-(5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorinan-2-yl)-4-(3-nitrophenyl)-3-pyridinecarboxylate hydrochloride (NZ-105), on whole cell Ca2+ current (ICa) in cultured vascular smooth muscle cells was investigated with the patch clamp technique. NZ-105 blocked ICa in a concentration-dependent manner when the command pulse ranged from +10 mV to –50 mV. The inhibitory effect of NZ-105 appeared at concentrations higher than 10 mol/l and it blocked ICa completely at a concentration of 1 nmol/l. The concentration which produced the half-maximal inhibitory effect was estimated to be around 20 mol/l. NZ-105 (500 pmol/l) completely blocked ICa elicited by depolarization to + 10 mV at a holding potential of –40 mV, whereas it blocked ICa by only 67% at a holding potential of –90 mV. NZ-105 (100 mol/l) shifted the steady-state inactivation curve by 40 mV to more negative potentials without affecting its slope factor. The blocking time constant of 500 mol/l NZ-105 was 57.6 + 9.9 s at a holding potential of –70 mV. These results indicate that NZ-105 has characteristics typical of dihydropyridines and binds to Ca2+ channels of vascular smooth muscle cells with a high affinity. They also suggested that the slow onset of its action is due to the slow binding of the drug to Ca2+ channels. Send offprint requests to S. Kokubun at the above address  相似文献   
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