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排序方式: 共有438条查询结果,搜索用时 15 毫秒
41.
Voutilainen M Färkkilä M Juhola M Nuorva K Mauranen K Mäntynen T Kunnamo I Mecklin JP Sipponen P 《The American journal of gastroenterology》1999,94(4):913-918
OBJECTIVES: In Barrett's esophagus (BE) normal squamous esophageal epithelium is replaced by specialized columnar epithelium (SCE). BE is related to gastroesophageal reflux disease (GERD) and is a risk factor for esophageal adenocarcinoma. SCE is detected also at normal-appearing esophagogastric junction without BE (junctional SCE). The relationships between junctional SCE, GERD, and cardia adenocarcinoma are obscure and controversial. The aims of the present study were to investigate the prevalence and demographics of junctional SCE and to compare these figures with those reported for BE, and esophageal and cardia adenocarcinoma. A further aim was to examine the association between junctional SCE and GERD, Helicobacter pylori infection, and gastritis. METHODS: One thousand one hundred-nineteen consecutive dyspeptic patients underwent gastroscopy and were enrolled into the study. RESULTS: Junctional SCE was detected in 110 patients (10%). The age-specific prevalence of junctional SCE increased with age. The male:female ratio was 1:1.1. In multivariate analysis, junctional SCE was independently and positively related to endoscopic erosive esophagitis (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.1-3.1), cardia inflammation (carditis) (OR, 3.1; 95% CI, 1.4-6.8), and age (OR, 1.4 per decade; 95% CI, 1.2-1.6), but not to corpus H. pylori infection (OR, 1.4; 95% CI, 0.7-2.8), antral (OR, 1.0; 95% CI, 0.5-2.1) or corpus (OR, 0.8; 95% CI, 0.4-1.8) gastritis, or intestinal metaplasia of the antral mucosa in stomach (OR, 1.2; 95% CI, 0.7-2.1). In univariate analysis, junctional SCE was, however, significantly more common in patients with antral-predominant atrophic gastritis (20%), compared with those with normal gastric histology (8%, p < 0.001). CONCLUSIONS: Junctional SCE is age related and may therefore be an acquired lesion. It is associated with cardia inflammation and endoscopic erosive esophagitis, but not with H. pylori infection or gastric intestinal metaplasia. Unlike BE and cardia cancer, junctional SCE occurs with similar frequency in men and women. 相似文献
42.
Cytochrome P-450scc (P-450scc) catalyzes the cholesterol side-chain cleavage reaction, a rate-limiting enzymatic step for progesterone synthesis in trophoblastic and other steroidogenic cells. Adrenodoxin is the iron/sulfur protein donating electrons to P-450scc during this reaction. We examined the effects of cholera toxin (CT), an activator of adenylate cyclase, and 12-O-tetradecanoylphorbol acetate (TPA), a phorbol ester protein kinase C activator, on the levels of mRNAs encoding P-450scc and adrenodoxin in JEG-3 choriocarcinoma cells. CT induced in a concentration- and time-dependent manner P-450scc and adrenodoxin mRNA levels to 8-fold and 1.5-fold above that of control, respectively. TPA also increased P-450scc and adrenodoxin mRNA levels about 3-fold and 1.5-fold above that of control, respectively. Epidermal growth factor (EGF) was found to weakly induce P-450scc mRNA accumulation with a maximal 20% stimulation above basal levels. The effects of CT and TPA were apparently additive on both mRNAs. The protein synthesis inhibitor cycloheximide diminished basal, CT-, TPA-, and EGF-stimulated P-450scc mRNA accumulation whereas the opposite was observed for the adrenodoxin mRNA. Insulin-like growth factor I (IGF-I) appeared to have no effect on either mRNA. These data indicate that: (1) the accumulation of P-450scc and adrenodoxin mRNAs is mainly controlled by the cyclic adenosine 3',5'-monophosphate (cAMP)-dependent pathway but their stimulation by TPA- and EGF-induced signals may also play a weaker synergistic role; (2) the protein synthesis inhibitor cycloheximide inhibits basal, CT-, TPA- and EGF-stimulated P-450scc mRNA levels while it increases the expression of adrenodoxin mRNA suggesting that in the malignant trophoblasts these two enzyme mRNAs are differentially controlled. 相似文献
43.
Expression of phosphorylcholine-specific B cells during murine development 总被引:1,自引:0,他引:1 下载免费PDF全文
NH Sigal AR Pickard ES Metcalf PJ Gearhart NR Klinman 《The Journal of experimental medicine》1977,146(4):933-948
The TEPC 15 (T15) clonotype, a putatively germline antibody specificity, does not appear in the neonatal B-cell repertoire until approximately 1 wk of age. This report extends this observation by the demonstration that (a) the T15 clonotype follows similar kinetics of appearance in germfree as well as conventionally-reared mice; (b) maternal influences and genetic background play a minor role in the development of the T15 clonotype since CBFI neonates raised by C57BL/6 or BALB/c mothers acquire the T15 clonotype at the same time in ontogeny as BALB/c neonates; (c) the lack of phosphorylcholine (PC)-specific B cells shortly after birth is reflected in a dearth of PC-binding cells in the neonate as well; and (d) no PC-specifc B cells are found in 19-day fetal liver or in bone marrow until 7 days of life, coincident with their appearance in the spleen. These findings, along with a previous report that PC-specific splenic B cells are tolerizable as late as day 10 after birth, confirm the invariant, late occurrence of the T15 clonotype and support a highly- ordered, rigorously predetermined mechanism for the acquisition of the B- cell repertoire. The results are discussed in light of other studies on the ontogeny of B-cell specificity, and in terms of the implications on the mechanism by which antibody diversity is generated. 相似文献
44.
45.
J K Huttunen E L?nsimies E Voutilainen C Ehnholm E Hietanen I Penttil? O Siitonen R Rauramaa 《Circulation》1979,60(6):1220-1229
A controlled trial is reported on the effects of mild-to-moderate physical activity on serum lipoproteins. After two baseline examinations 100 asymptomatic middle-aged men were randomly assigned to exercise and control groups. The exercise group participated in a 4-month exercise program that consisted of 3-4 weekly sessions. The control group was advised to maintain their previous exercise habits. The success of the program was corroborated by the increase in VO2 in the training group, but not in the control group. Serum triglycerides decreased from 1.54 +/- 0.10 to 1.27 +/- 0.08 mmol/1 (p less than 0.001) and high-density lipoprotein (HDL) cholesterol increased from 1.27 +/- 0.04 to 1.41 +/- 0.04 mmol/1 (p less than 0.01) in the exercise group during the trial. No change was seen in the control group. As the concentration of apolipoprotein AI stayed constant in both groups, the ratio HDL cholesterol/apolipoprotein AI increased only in the exercise group. The level of low-density lipoprotein (LDL) cholesterol and apolipoprotein AII decreased in both groups during the trial. The alterations in serum triglycerides and HDL cholesterol in the exercise group were not dependent on weight reduction; similar changes were also seen in subjects with constant body weight during the intervention. 相似文献
46.
Louheranta AM Schwab US Sarkkinen ES Voutilainen ET Ebeling TM Erkkilä AT Turpeinen AK Uusitupa MI 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2000,10(4):177-187
BACKGROUND AND AIMS: To investigate the effect of a reduced-fat diet and a monoene-enriched diet (MUFA diet) on serum lipids, glucose and insulin metabolism in subjects with elevated cholesterol and triglyceride concentrations. METHODS AND RESULTS: Eighteen subjects with elevated serum cholesterol and triglyceride concentrations consumed the MUFA diet (39% of energy (E%) as fat and 21 E% monoenes) and the reduced-fat diet (34 E% fat, 16 E% monoenes) for 4 weeks according to a randomized cross-over design. Both periods were preceded by consumption of a standardized baseline diet for 2 weeks. Serum lipid and lipoprotein concentrations were determined at the beginning and end of each diet period. A frequently sampled intravenous glucose tolerance test was performed after the MUFA diet and the reduced-fat diet. Insulin sensitivity index (SI) was 40% higher after the reduced-fat diet than after the MUFA diet (2.42 +/- 0.42 vs 1.73 +/- 0.24 10(-4) min-1 U-1 ml-1, p = 0.018). This change in insulin sensitivity was seen in 13 subjects and was most evident in those who began with the MUFA diet. Compared to the baseline diet (high in saturated fat), both experimental diets lowered serum total and LDL cholesterol concentrations (6.6-6.9%, p < 0.05 and 7.4-8.0%, p < 0.05 respectively). CONCLUSIONS: Both diets were equally effective in lowering serum lipid concentrations, but the reduced-fat diet resulted in better insulin sensitivity. 相似文献
47.
Mackinnon S; Papadopoulos EB; Carabasi MH; Reich L; Collins NH; Boulad F; Castro-Malaspina H; Childs BH; Gillio AP; Kernan NA 《Blood》1995,86(4):1261-1268
Infusions of large numbers (> 10(8)/kg) of donor leukocytes can induce remissions in patients with chronic myeloid leukemia (CML) who relapse after marrow transplantation. We wanted to determine if substantially lower numbers of donor leukocytes could induce remissions and, if so, whether this would reduce the 90% incidence of graft-versus-host disease (GVHD) associated with this therapy. Twenty-two patients with relapsed CML were studied: 2 in molecular relapse, 6 in cytogenetic relapse, 10 in chronic phase, and 4 in accelerated phase. Each patient received escalating doses of donor leukocytes at 4- to 33-week intervals. Leukocyte doses were calculated as T cells per kilogram of recipient weight. There were 8 dose levels between 1 x 10(5) and 5 x 10(8). Lineage-specific chimerism and residual leukemia detection were assessed using sensitive polymerase chain reaction (PCR) methodologies. Nineteen of the 22 patients achieved remission. Remissions were achieved at the following T-cell doses: 1 x 10(7) (n = 8), 5 x 10(7) (n = 4), 1 x 10(8) (n = 3), and 5 x 10(8) (n = 4). To date, 15 of the 17 evaluable patients have become BCR-ABL negative by PCR. The incidence of GVHD was correlated with the dose of T cells administered. Only 1 of the 8 patients who achieved remission at a T-cell dose of 1 x 10(7)/kg developed GVHD, whereas this complication developed in 8 of the 11 responders who received a T-cell dose of > or = 5 x 10(7)/kg. Three patients died in remission, 1 secondary to marrow aplasia, 1 of respiratory failure and 1 of complications of chronic GVHD. Sixteen patients who were mixed T-cell chimeras before treatment became full donor T-cell chimeras at the time of remission. Donor leukocytes with a T-cell content as low as 1 x 10(7)/kg can result in complete donor chimerism together with a potent graft-versus-leukemia (GVL) effect. The dose of donor leukocytes or T cells used may be important in determining both the GVL response and the incidence of GVHD. In many patients, this potent GVL effect can occur in the absence of clinical GVHD. 相似文献
48.
Inhibin/activin betaB-subunit expression in pheochromocytomas favors benign diagnosis 总被引:3,自引:0,他引:3
Salmenkivi K Arola J Voutilainen R Ilvesmäki V Haglund C Kahri AI Heikkilä P Liu J 《The Journal of clinical endocrinology and metabolism》2001,86(5):2231-2235
Malignancy of pheochromocytomas is difficult to estimate on the basis of histopathological features. Good prognostic markers are not available. In our search for new markers to differentiate malignant pheochromocytomas from benign ones we tested the value of inhibin/activin subunit expression. Inhibins are heterodimeric glycoproteins consisting of an alpha-subunit and either a betaA- or a betaB-subunit. Activins are composed of beta-subunits only. Immunohistochemically inhibin/activin betaB-subunit was strongly positive in the normal adrenal medulla, but the cortex was negative. A striking difference was found in inhibin/activin betaB expression between benign and malignant pheochromocytomas. The majority of benign adrenal tumors (27 of 30) showed strong or moderate immunoreactivity, whereas all seven malignant tumors were negative or only weakly positive for inhibin/activin betaB-subunit. The percentage of positively staining cells varied greatly in extraadrenal pheochromocytomas and in those benign tumors that showed over 5 mitoses/10 high power fields, necrosis, or capsular or vascular invasion, here called borderline tumors. Inhibin/activin betaB messenger ribonucleic acid was also found in pheochromocytomas. However, no significant differences in messenger ribonucleic acid levels were found in various types of tumors. Weak immunohistochemical positivity for inhibin/activin betaA-subunit was detected in the adrenal cortex, but the medulla and most of the pheochromocytomas were negative. Our data show that inhibin/activin betaB-subunit is expressed in normal adrenal medullary cells. Strong staining is found in most benign adrenal pheochromocytomas, whereas malignant tumors are almost negative. This suggests that loss of inhibin/activin betaB-subunit expression in pheochromocytomas may be used as an indicator of malignant potential. 相似文献
49.
50.
I M Penttil? J Herranen E Lampainen E Voutilainen 《Clinica chimica acta; international journal of clinical chemistry》1987,170(2-3):143-149
According to the present study, in hyperlipidemias where triglyceride values in serum are raised, the triglyceride values are associated with increased amounts of branched-chain alpha-keto-acids (BCKA) in the serum. In particular, the concentration of alpha-ketoisocaproic acid (KICA), which in the control sera was 34.4 mumol/l, was in type IIB hyperlipidemia 40.4% and in type IV 49.4% higher than in controls with normal serum lipid values. In type IV hyperlipidemia, values for alpha-ketoisovaleric acid (KIVA) and alpha-keto-beta-methyl-n-valeric acid (KMVA) were also high when compared to the corresponding mean values of the controls, 7.1 and 18.8 mumol/l. The respective differences were 57.7 and 44.1 per cent. In type IIB hyperlipidemia, KIVA was significantly and KMVA insignificantly increased compared to the control group. In type IIA hyperlipidemia with normal triglyceride values, none of the three BCKA differed significantly from the controls. These results also indicate that the increased amounts of individual BCKA somehow depend on the concentration of triglycerides in serum, while no relationship was found between BCKA values and cholesterol concentration. 相似文献