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1.
The B cell functional response following ligation of surface(s) lgM is dependent upon the differentiation stage of the populationstudied: cross-linking slgM promotes proliferation of restingtonsillar follicular mantle (FM) B lymphocytes but induces apoptosisin the susceptible Epstein- Barr virus genome-negative Burkittlymphoma (BL) cell line Ramos (Ramos-BL). This study investigateswhether phosphatidylinositol-3-kinase (Pl3-kinase), which hasbeen reported to be intimately involved in the regulation ofcellular growth, plays a role in the regulation of these sig-promoted B cell responses, and uses the selective and irreversibleinhibitor of Pl3-kinase activity, wortmannin (Wm). In Ramos-BLB cells, at 8 h post-treatment, Wm triggers a transient increasein apoptosis of 16 ± 6.9% with a concomitant cellularloss of 16 ± 6.1% from the G1 phase of cell cycle; [3H]thymidineincorporation also decreases by 33 ± 5.0%, from 37,274c.p.m. ± 10% to 25,127 c.p.m. ± 4.0%. Moreover,at 72 h culture, Wm inhibits anti-lgM-induced FM B lymphocytelevels of [3H]thymidine incorporation typically by 47% and triggers80% apoptosis from the G0G1 phase of cell cycle. Ramos-BL Bcells exhibit high basal levels of Pl3-kinase activity, as determinedby immunoprecipitation with antibody to the p85 regulatory subunitof Pl3-kinase and 32P incorporation into phosphatidylinositol,which is not significantly affected by anti-lgM stimulation;by contrast, anti-lgM stimulates significant Pl3-kinase activityover negligible basal levels in FM B lymphocytes. Pre-treatmentwith Wm inhibits Pl3-kinase activity in both cell types. Takentogether these data indicate that in Ramos-BL B cells slgM-triggeredgrowth arrest and apoptosis is Pl3- kinase independent, whereasPl3-kinase activity is critical for slgM-triggered mitogenesisof FM B lymphocytes. Thus Pl3-kinase plays a pivotal role inthe regulation of both normal and neoplastic B lymphocyte progressionthrough the cell cycle, such that if this Pl3-kinase-dependentpathway is inhibited these cells default to apoptosis.  相似文献   
2.
Summary: This is the first report of the largest study of blood pressure measurement in pregnancy in a New Zealand population using standardized definitions and methodology. Over 3,800 women who delivered in an 8-month period in the Wellington region were included in the study. Blood pressure measurement and the presence of oedema and proteinuria were recorded from booking until delivery and in the puerperium. Only 2.7% of women were unable to be contacted after delivery for details on outcomes. The results established normal ranges for blood pressure throughout pregnancy. The data show that Mood pressure greater than 140/90 until 35 weeks' gestation is outside 2 standard deviations at all gestations and justifies using these measurements as the definition of hypertension in pregnancy. The fall in blood pressure in the 2nd trimester was less than 1 mm Ffg per week in both the systolic and diastolic pressures. This fall was smaller than previously recorded in other studies. Gestational hypertension was the commonest blood pressure abnormality occurring in 15.2% of the population. This represented 69% of the pregnant women with a hypertensive disorder. The overall incidence of both gestational hypertension and preeclampsia was 18.5% which is higher than reported in other parts of the world. In this study obesity was significantly associated with hypertensive disorders in pregnancy. An arm circumference of >33 cm, one of the measurements of obesity, was found in 6.8% of the study population. Even after the effect of arm circumference was taken into account, hypertensive disorders were also more common in Pacific Island women. Ankle oedema was significantly associated with the development of both gestational hypertension and preeclampsia but the incidence of oedema was noted in only 11.9% of the subjects.  相似文献   
3.
4.
Four hundred out of 422 patients with primary gastric cancer seen from 1965 to 1979 underwent surgical treatment and were studied retrospectively. Fifty-eight percent underwent curative procedures. The five year survival rate was 19.14%. Subtotal and total gastrectomy gave survival rates of 35.8% and 9% respectively (p less than 0.05). Postoperative mortality (24.2%) was influenced by both the type of procedure performed (p less than 0.001) and the stage of the neoplasis (p less than 0.001). This study confirms the influence of staging on short, intermediate and long term survival and demonstrates the importance of the early diagnosis of gastric cancer in carrying out effective surgical treatment.  相似文献   
5.
While there is a burgeoning body of research linking smoking during pregnancy to problem behaviour in offspring, a major criticism of this work has been the crude measurement of exposure in these studies (e.g. retrospective, self-reported only) that could lead to biased estimates. To address this issue, we used a pregnancy cohort with repeated prospective measures of exposure as well as biological assays to generate estimates of exposure patterns using a range of modelling techniques. In this paper we report on the analytical approaches we have developed, including patterns of exposure over time and best-estimate approaches that combine self-report and cotinine measures, and compare their predictive value in relation to different dimensions of fetal growth as a first step towards examining the utility of greater precision of exposure measurement.
Surprisingly, in this sample the more complex assessments of exposure, including biological measures, generally did not perform better than simple indicators of exposure based on repeated self-report measures, with one exception: a combined self-report cotinine 'best estimate' of third trimester exposure was uniquely associated with lower brain : body ratio. Further study is needed using more sophisticated cotinine assays and testing prediction of a range of outcomes to ascertain whether these findings represent true differences or are specific to the sample, methods and outcomes used. Such research will inform the development of guidelines for adequate exposure characterisation in developmental studies.  相似文献   
6.
Edited by Lauren Dundes. Walnut Creek (CA): Altamira Press, 2003. 239 pages. $27.95, paperback, $75.00, hardback.  相似文献   
7.
A hypothalamic pathogenesis for the reduced GH secretion in aging has been reported for both animal and man. To further address this issue we studied in 31 elderly normal subjects (6 males and 25 females, aged 66-90 yr) and in 22 young healthy controls (13 males and 9 females, aged 20-35 yr) the GH responses to GHRH test (GHRH29, 1 microgram/kg i.v. as a bolus at 0 min) alone and combined with pyridostigmine, a cholinesterase inhibitor (PD, 120 mg po 60 min before GHRH), or with arginine (ARG, 30 g in 100 ml infused from 0 to 30 min). Serum IGF-I levels were lower in elderly than in young subjects (mean +/- SE: 86.9 +/- 7.2 vs 288.7 +/- 22.1 micrograms/L, p < 0.01). The GHRH-induced GH increase was lower in elderly than in young subjects (p < 0.01). PD increased the GH response to GHRH in both groups (p < 0.001), but in elderly subjects this response persisted lower (p < 0.0001) than that observed in young adults. Also ARG coadministration potentiated the GHRH-induced GH release in both groups (p < 0.0001) but in this case the elderly's responses overlapped with the young's. The GH increase observed after combined administration of ARG and GHRH was higher (p < 0.0001) than that elicited by PD plus GHRH in elderly but not in young subjects. Analyzing individual GH responses, a GH peak below the limit of normality for young adults was observed in 19 (61.3%) elderly subjects after PD plus GHRH administration while ARG plus GHRH test elicited a normal GH peak in all but one.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
8.
Sequential salivary gland scintigraphy with 99mTc-technetium pertechnetate (Tc-99) is a safe, minimally invasive test for study of major salivary glands. However, its relationship to salivary function has not been investigated in detail. We have investigated the relationship between major salivary gland flow rates and Tc-99 scans and developed a new rating scale using scans of a control group with normal salivary function. Salivary flow rates and Tc-99 scans were obtained from healthy, non-medicated subjects (n = 33) and from xerostomic patients (n = 22). There were significant differences between the groups for salivary flow rates and Tc-99 ratings. Significant correlations were found between salivary flow rates and Tc-99 ratings in the control and xerostomic groups. The Tc-99 rating scale proved reliable in assessing salivary dysfunction, and showed a high inter-examiner correlation. These results demonstrate the usefulness of salivary gland scintigraphy in assessing major salivary gland flow rates and the utility of a new rating scale.  相似文献   
9.
Laboratory studies suggest that ghrelin is involved in bone metabolism, but studies of ghrelin and bone in humans are limited. We studied sex-specific associations of ghrelin with BMD, NTX, and bone loss. Ghrelin was not associated with BMD or bone loss in either sex. There was a significant inverse association with NTX in men but not in women. INTRODUCTION: Ghrelin is a gastric hormone recently shown to be associated with bone metabolism in animal and in vitro studies. Studies in humans are limited. We investigated the association of ghrelin with BMD, the bone resorption marker N-telopeptide (NTX), and bone loss in older men and women. MATERIALS AND METHODS: Participants were 977 community-dwelling men and non-estrogen-using postmenopausal women, 50-91 years of age. Plasma ghrelin was measured by radioimmunoassay from blood obtained between 1984 and 1987. Between 1988 and 1991, BMD was measured at the midshaft radius by single photon absorptiometry and at the femoral neck, total hip, and lumbar spine by DXA. Axial BMD measurements were repeated an average of 4 years later in 544 participants. Bone turnover was assessed by NTX in urine obtained at the same time as the initial BMD. Multiple regression analyses were used to test sex-specific associations of ghrelin with BMD, NTX, and bone loss in both sexes. RESULTS: No significant ghrelin-BMD or ghrelin-bone loss associations were observed in either sex, after adjusting for age and body mass index (BMI). Ghrelin was inversely associated with NTX in men and positively associated with NTX in women, independent of age. After adjusting for both age and BMI, this association reached statistical significance in men and was weakened in women. CONCLUSIONS: Ghrelin may be associated with bone turnover, but there is no evidence for an association with BMD or short-term change in BMD in older adults.  相似文献   
10.
Background: Pain after amputation is common but difficult to treat, and few controlled treatment studies exist.

Methods: In the current study, 94 treatment-naive posttraumatic limb amputees with phantom pain (intensity: mean visual analog scale score [0-100], 40 [95% confidence interval, 38-41]) were randomly assigned to receive individually titrated doses of tramadol, placebo (double-blind comparison), or amitriptyline (open comparison) for 1 month. Nonresponders were crossed over to the alternative active treatment.

Results: After 1 month, phantom pain intensity was 1 (0-2) in the 48 tramadol responders (mean dose, 448 mg [95% confidence interval, 391-505 mg]), 0 (0-0) in the 40 amitriptyline responders (55 [50-59] mg), and 0 (0-0) in the 2 placebo responders, with similar effects on stump pain. Cytochrome P-450 2D6 slow metabolizers derived greater analgesia from tramadol and less from amitriptyline compared with fast metabolizers in the first treatment week (P < 0.01). Electrical pain thresholds increased and pain during suprathreshold stimulation decreased markedly on the stump and, to a lesser extent, on the contralateral limb after 1 month of treatment with amitriptyline or tramadol. Adverse effects were minor in all groups, but more common with tramadol.  相似文献   

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