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81.
82.

Purpose

The prenatal assessment of lung volume is becoming increasingly important in determining survival in both preterm infants and newborns affected by pulmonary hypoplasia. This study aimed to examine the lung volumes in the human fetus at varying gestational ages.

Materials and methods

Using anatomical, hydrostatic (water displacement according to Archimedes’ patent) and statistical methods (one-way ANOVA test for paired data and post-hoc Bonferroni test, Kolmogorov–Smirnov test, Levene’s test, Student’s t test, regression analysis), volumes of the right and left lungs were measured in 67 human fetuses of both sexes (35 males, 32 females) aged 16–25 weeks, derived from spontaneous abortions and stillbirths.

Results

No male–female differences concerning the right and left pulmonary volumes were found. The mean volume of the right lung increased from 1.43 ± 0.25 to 8.45 ± 2.66 cm3, according to the cubic function y = –1.592 + 0.0007 × age3 ± 0.851 (R 2 = 0.84). The volumetric growth of the left lung, from 1.24 ± 0.22 to 6.78 ± 3.03 cm3, followed the cubic model y = –1.110 + 0.0005 × age3 ± 0.794 (R 2 = 0.78). The total pulmonary volume increased from 2.67 ± 0.47 to 15.22 ± 5.58 cm3, in accordance with the cubic model y = –2.729 + 0.0012 × age3 ± 1.598 (R 2 = 0.83). The mean volumes of the right and left lungs accounted for 54.9 ± 2.0 and 45.1 ± 2.0 %, respectively, of the total lung volume.

Conclusions

No sex differences are found between the lung volumes in the fetus. The growth of fetal lung volume follows a three-degree polynomial function. Throughout the analyzed period the two lungs grow proportionately to each other, with the volumetric predominance of the right lung. The lung volumes in the fetus are of great relevance in the evaluation of the normal pulmonary growth and the diagnosis of pulmonary hypoplasia.  相似文献   
83.
Detection of human bocavirus in hospitalised children   总被引:1,自引:0,他引:1  
Aim:   The objectives of this study are to assess the frequency of human bocavirus (HBoV) infection in hospitalised children and to study the clinical symptoms associated with the detection of HBoV.
Methods:   Two groups of hospitalised children were included in this study: group 1 consisted of 1946 children hospitalised from 1st September 2004 to 30th May 2005, and group 2 consisted of 448 children hospitalised from 1st November 2003 to 30th March 2004. The respiratory specimens were tested by polymerase chain reaction.
Results:   In the first group, HBoV was detected by polymerise chain reaction in 11/828 (1.3%) of nasal specimens that tested negative for other respiratory viruses. One child tested positive for HBoV in both a nasal aspirate and stool sample. In the second group, nasal specimens were tested for all respiratory viruses, including HBoV. The presence of HBoV infection was detected in seven children (1.6%). Detection of a mixed viral population was observed in four of these children. The main symptoms in children infected with HBoV were rhinitis (50%), cough (45%), dyspnoea (28%), wheezing (28%), fever (23%) and diarrhoea (22%). The final clinical diagnoses were bronchiolitis (seven children), rhinopharyngitis (five children), the exacerbation of asthma (two children) and pneumonia (one child). Moreover, four children have associated gastroenteritis.
Conclusion:   These results contribute to the interest in the HBoV detection in children. HBoV detection in hospitalised children with or without any other respiratory virus detection was essentially associated with lower respiratory tract infection and in a lower score with upper respiratory tract infection and gastroenteritis.  相似文献   
84.
85.
BackgroundEvidence suggests that probiotics, as a group, are reducing the risk of necrotizing enterocolitis (NEC). The efficacy of each probiotic strain needs to be evaluated separately.ObjectiveTo evaluate the efficacy of administering Lactobacillus rhamnosus ATC A07FA (L. rhamnosus) for the prevention of necrotizing enterocolitis (NEC) ≥2 by the criteria of Bell in very low-birth-weight preterm infants.MethodPreterm infants children fulfillingthe inclusion criteria (gestational age <32 weeks and birth weight <1500 g and partial orfull enteral feeding) were enrolled in a randomized, double-blind, placebo-controlled trial. They received L. rhamnosus (commercially available as Lakcid) at a dose of 1.2 × 1010 CFU or a placebo orally, twice daily, for the duration of the hospital stay. The primary outcome measures were NEC ≥2 by the criteria of Beli, sepsis and death.ResultsThe study was stopped prematurely because of slow recruitment. Data from 55 preterm infants were included in the fina? analysis. In the experimental group, compared with the placebo group, the risk of developing NEC ≥2 by the criteria of Beli was reduced, however the difference was not statistically significant (1/30; 3.3% versus A/25; 16%, RR 0.2, 95% Cl 0.02 do 1.75). L. rhamnosus did not significantly affect the risk of developing sepsis or death. There was also no difference between the probiotic and placebo groups for any of the other secondary outcomes. No adverse events were reported.ConclusionThe administration of L. rhamnosus ATC A07FA compared with placebo had no effect on the incidence of NEC. Further studies with sufficient sample size are warranted.  相似文献   
86.
Morphologic features of Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) overlap. No single phenotypic marker or molecular abnormality is pathognomonic. We tested a panel of 8 germinal center (GC) and activated B-cell (ABC) markers for their ability to separate BL and DLBCL. We diagnosed 16 BL and 39 DLBCL cases from 21 patients with AIDS and 34 without AIDS based on traditional morphologic criteria, Ki-67 proliferative index, and c-myc rearrangement (fluorescence in situ hybridization). After immunohistochemically staining tissue microarrays of BL and DLBCL for markers of GC (bcl-6, CD10, cyclin H) and ABC (MUM1, CD138, PAK1, CD44, bcl-2), we scored each case for the percentage of positive cells. Hierarchical clustering yielded 2 major clusters significantly associated with morphologic diagnosis (P < .001). For comparison, we plotted the sum of the GC scores and ABC scores for each case as x and y data points. This revealed a high-GC/low-ABC group and a low-GC/high-ABC group that were associated significantly with morphologic diagnosis (P < .001). Protein expression of multiple GC and ABC markers can separate BL and DLBCL.  相似文献   
87.
Recombinant FimH adhesins of type 1 fimbriae from Salmonella enterica serovar Gallinarum biovars Gallinarum and Pullorum, in contrast to those of Salmonella enterica serovar Typhimurium, did not bind to high-mannose oligosaccharides or to human colon carcinoma HT-29 cells. However, mutated FimH proteins from biovar Gallinarum and biovar Pullorum, in which the isoleucine at position 78 was replaced by the threonine found in S. enterica serovar Typhimurium, bound well to glycoproteins carrying high-mannose oligosaccharides and colon carcinoma cells. The loss of sugar-binding properties by biovar Gallinarum and biovar Pullorum FimH adhesins, which are a part of the type 1 fimbriae, is most probably the result of a single T78I mutation, as was proven by site-directed mutagenesis of FimH proteins.  相似文献   
88.
INTRODUCTION: The successful use of hepatocytes depends on a reliable demonstration of the functional and morphological integrity of isolated cells. Herein we investigated whether the isolation and cryopreservation of primary human hepatocytes can compromise cell viability and liver-specific characteristics. MATERIAL/METHODS: Hepatocytes were isolated from encapsulated human liver segments by a modified 2-step perfusion technique. Isolated cells were Percoll-purified, cryopreserved, and stored in liquid nitrogen for 1-12 months. For rapid assessment of fresh and cryopreserve/thawed hepatocyte yield and viability, the cells were stained with trypan blue or labeled with fluorochromes. For immunocytochemical analysis, the cells were labeled with monoclonal antibodies for the presence of the following antigens and chemokines: CD3, CD45Ro, CD45Ra, CD34, CD68, CD90, CD95, CD20, HLA-DR, Ki67, PCNA, Bcl-2, p53, CXCR3, CXCR4, and SDF-1. The cells were tested for several specific functions, such as ureagenesis, energy status, MTT activity, lactate dehydrogenase leakage, and total CYP450 content. RESULTS: Assessment of both freshly isolated (Percoll-purified) and cryopreserved/thawed hepatocytes revealed a low constitutive level of contamination by non-parenchymal cells compared with crude (unpurified) preparations and tissue sections. All viable hepatocytes showed intact morphology and retained CYP450 protein, energy status, and urea synthesis. CONCLUSIONS: Modifications in hepatocyte preparations, such as depletion of dead, damaged, and nonparenchymal cells, improves cell purity, which can be adapted to further evaluation of hepatocyte immunogenicity. These data illustrate the importance and feasibility of human hepatocyte banking.  相似文献   
89.
Objective: Evaluate physiologic factors associated with reduced maternal perception of fetal movements (RFM).

Methods: A historical cohort study of all women (years 2011–2013, n?=?399) that visited the maternal emergency room (ER) (gestational age 24?+?0–42?+?0) due to RFM (group A), that was compared to a control group consisted from women with normal perception of fetal movements (group B). Groups were compared for maternal characteristics (age, gravity, parity, BMI), gestational age, placental location, gestational age at birth and fetal outcomes (birth-weight and Apgar scores).

Results: In a multivariate regression analysis, including maternal age, height, weight, BMI, gestational age on admission to ER, gravity, parity and placental location, only two variables remained significantly associated with RFM – nulliparity (OR?=?2.28, p?=?0.001) and anterior placenta (OR?=?1.44, p?=?0.034). Group A was not associated with lower Apgar scores (1 and 5-min, p?=?0.40 and 0.57, respectively) or low birth-weight (p?=?0.76), nor was it associated with prematurity (p?=?0.41), low (<7) 5-min Apgar score, fetal death or neonatal death.

Conclusions: Reduced fetal movements are associated with anterior placenta and nulliparity.  相似文献   
90.
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