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71.
In 2009, the Global Alliance to Prevent Prematurity and Stillbirth Conference charged the authors to propose a new comprehensive, consistent, and uniform classification system for preterm birth. This first article reviews issues related to measurement of gestational age, clinical vs etiologic phenotypes, inclusion vs exclusion of multifetal and stillborn infants, and separation vs combination of pathways to preterm birth. The second article proposes answers to the questions raised here, and the third demonstrates how the proposed system might work in practice.  相似文献   
72.
OBJECTIVES: Oral hairy leukoplakia (HL) is an acan-thotic, hyperparakeratotic lesion characterised by the presence of a replicative Epstein-Barr virus (EBV) infection in the superficial and adjoining layers of the epithelium. EBV or its gene products are capable of modifying epithelial differentiation. The aim of this study was to establish whether the presence of EBV was associated with an alteration in cell turnover by assessing bromodeoxyuridine (BrdU) incorporation and Ki 67 expression in lesional tissue and control mucosa.
METHODS: Biopsies of HL together with age, site and sex matched controls ( n = 7 and 8 respectively) were incubated in 200 μM BrdU in vitro , fixed in methacarn and processed to paraffin wax. Following acid hydrolysis, incorporated BrdU and Ki 67 were identified in serial 5 fim sections using a three-stage immunoperoxidase technique and cell density expressed as the number of positive cells per mm basement membrane length.
RESULTS: Overall, there was no difference in the number of BrdU positive cells per mm basement membrane length between control and HL tissue. However, within HL alone, the presence'of focal EBV replication was associated with a significant reduction in the number of basal cells incorporating BrdU compared to adjacent EBV free areas (P < 0.05). There was no significant difference between Ki 67 positive cells in control and HL tissue and no evidence of a reduction of Ki 67 positive cells in areas associated with EBV replication.
CONCLUSIONS: These results suggest that there is no evidence of a generalised alteration of the proliferative capacity of basal cells in HL, although the focal reduction in BrdU incorporation may reflect subtle changes on cell turnover by EBV infection.  相似文献   
73.
Lymphadenopathy is the commonest presentation in HIV positive individuals. Fine needle aspiration cytology of 196 HIV positive patients was studied during six monthly review. 75% paients in this study who were asymptomatic were detected to have lymphadenopathy during the surveillance. 82% had lymph nodes smaller than 1cm size. Lymphadenopathy at more than one site was observed in 46.8% cases. Commonest opportunistic infection noticed was tuberculosis (TB) in 34.2%. Cyto-morphologically reactive pattern with Add fast bacilli (AFB) positivity was observed in 16.4% of TB cases. In 2.9% cases AFB were detected even in the tissue fluid. Negative images of AFB were observed in the macrophages in 3 cases. TB was detected with equal frequency in both asymptomatic and symptomatic groups. Axillary nodes pose problem due to deeper location. False positives were a case of dermatopathic lymphadenopathy and a case of Kimura''s disease. False negatives include two cases of TB lymphadenitis. Pathogens should be looked for irrespective of cyto-morphology. Biopsy should be done to confirm cases of lymphomas. Fine needle aspiration cytology should be included in the protocol of six monthly review of HIV infected cases.KEY WORDS: AIDS, FNAC, HIV, Lymph node, Tuberculosis  相似文献   
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Blom  M; Tool  AT; Kok  PT; Koenderman  L; Roos  D; Verhoeven  AJ 《Blood》1994,83(10):2978-2984
Eosinophil functions can be modulated by several cytokines such as granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin- 3 (IL-3), and IL-5. We have investigated the modulatory role of these cytokines on the interaction of human eosinophils with opsonized particles (serum-treated zymosan [STZ]). Addition of STZ to eosinophils isolated from the peripheral blood of normal human donors resulted in an interaction of the STZ particles with only 15% to 25% of the cells. Treatment of the eosinophils with GM-CSF, IL-3, or IL-5 strongly enhanced both the rate of particle binding and the percentage of eosinophils binding STZ. The effect of the cytokines is most likely mediated by a change in affinity of the complement receptor type 3 (CR3) on the eosinophils for the complement fragment iC3b on the STZ particles. This is indicated by the observation that (1) the effect of the cytokines on STZ binding was prevented by a monoclonal antibody against the iC3b-binding site on CR3 and (2) the enhanced binding was already apparent before upregulation of CR3 on the cell surface was observed. In a previous study, similar results were obtained with platelet-activating factor (PAF)-primed eosinophils. Because we found that the cytokines strongly enhanced the STZ-induced PAF synthesis, we investigated the role of both released PAF and cell-associated PAF in the priming phenomenon by the cytokines. Cytokine priming appeared to be largely independent of the synthesis of PAF.  相似文献   
76.
Yue  Wentao  Zhang  Enjie  Liu  Ruixia  Zhang  Yue  Wang  Chengrong  Gao  Shen  Su  Shaofei  Gao  Xiao  Wu  Qingqing  Yang  Xiaokui  Papageorghiou  Aris T.  Yin  Chenghong 《European journal of epidemiology》2022,37(3):295-304
European Journal of Epidemiology - The China birth cohort study (CBCS) is a prospective longitudinal, mega-cohort study and the first national-based birth cohort study, aiming to establish a birth...  相似文献   
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OBJECTIVES: To determine the safety and efficacy of imiquimod (Aldara) 5% cream in the treatment of prepuce-associated warts in uncircumcised males. METHODS: An open-label study in six UK medical centres with 35 uncircumcised males with prepuce-associated warts treated with imiquimod 5% cream three times per week for up to 16 weeks. Other anogenital warts were also treated. RESULTS: Three times weekly application of imiquimod was found to be safe, with erythema as the most commonly reported local skin reaction. Forty per cent of patients had complete clearance of anogenital warts within 16 weeks. CONCLUSIONS: Imiquimod cream at a dosing regimen of three times per week, is effective and has an acceptable safety profile in the treatment of prepuce associated warts and other external anogenital warts in uncircumcised males.  相似文献   
80.
Thirteen carnitine-deficient children (mean age, 16.1 ±2.56 years) on a three-times-weekly hemodialysis program for at least 1 year, and 11 healthy age matched children were involved in the study. All the patients had stable blood pressure and hemoglobin (Hb) levels with a maintenance dose of erythropoetin and none were digitalized. The total carnitine (TC) and free carnitine (FC) plasma levels were sampled prior to hemodialysis (HD) before and after 3 months of carnitine supplementation. A free carnitine (FC) to acylcarnitine (AC) ratio less than 4 was defined as carnitine deficiency. Intravenous L-carnitine was injected at a dose of 20–4.0 mg/kg three times weekly at the end of each dialysis session for a 3-month period. Echocardiographic examination was performed the day following HD, before and after carnitine treatment. Systolic and diastolic functions of the left ventricle, including the ejection fraction, were measured. Almost all the parameters were significantly different in controls and hemodiaiyzed patients. In carnitine-deficient hemodiaiyzed patients. 3 months of L-carnitine supplementation resulted in a significant increase in blood carnitine levels and the FC/AC ratio, but this was not associated with any significant improvement of cardiac function. Furthermore no significant changes were observed in plasma triglycerides, total cholesterol or other lipoprotein parameters before or after carnitine supplementation. Although there was a moderate increase in mean hematocrit (Hct) and Hb levels, these also did not reach statistically significant levels. These results suggest that the 3 months of carnitine supplementation is not sufficient to ameliorate cardiac function or increase Hb levels in children.  相似文献   
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