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51.
Serum levels of pregnancy zone protein (PZP) were measured in 506 apparently normal males and 329 normal non-pregnant females, the age range being 18 to 70 years. The estimations of PZP were performed by sensitive radiorocket-line immunoelectrophoresis. The distribution of the data had a marked positive skew in both sexes which was reduced following logarithmic transformation. Serum concentrations in both men and women were found to increase significantly with advancing age. This increase and the mean concentrations were significantly higher in females.  相似文献   
52.
BACKGROUND: Periodontitis shares several clinical and pathogenic characteristics with chronic arthritis, and there is some degree of coexistence. The aims of this study were to elucidate whether patients with localized aggressive periodontitis (LAgP), generalized aggressive periodontitis (GAgP), juvenile idiopathic arthritis (JIA), and rheumatoid arthritis (RA) share periodontal and hematological characteristics distinguishing them from individuals free of diseases. METHODS: The study population consisted of white adults (or=4 mm, CAL>or=2 mm, and ABL>or=2 mm compared to controls. The percentage of sites with CAL>or=2 mm significantly correlated with the levels of IgM-RF and IgA-RF. Missing teeth in JIA and RA patients were not lost due to periodontitis. Patients with GAgP showed higher levels of leukocytes, including neutrophils, and CRP compared to controls. In part, JIA and RA patients showed similar results. CONCLUSIONS: Young adults with RA may develop periodontal destruction, and these patients require professional attention. Both differences and similarities in periodontal and hematological variables were seen in individuals with periodontitis, JIA, and RA.  相似文献   
53.
The highly leukotoxic JP2 clone of Actinobacillus actinomycetemcomitans is strongly associated with periodontitis in adolescents. Availability of the DNA sequence of the complete genome of A. actinomycetemcomitans strain HK1651, a representative strain of the JP2 clone (http://www.genome.ou.edu/act.html), has provided new possibilities in basic research regarding the understanding of the pathogenesis of A. actinomycetemcomitans in periodontitis. This case report describes the periodontal treatment of the original source of A. actinomycetemcomitans HK1651, a 16-year-old Ghanaian adolescent girl with aggressive periodontitis. The bacterial examination involved polymerase chain reaction analysis for presence of JP2 and non-JP2 types of A. actinomycetemcomitans. The treatment, including periodontal surgery supplemented by antibiotics, arrested the progression of periodontitis for more than 10 years. Initially, infection by A. actinomycetemcomitans, including the JP2 clone, was detected at various locations in the oral cavity and was not limited to the periodontal pockets. Post-therapy, the JP2 clone of A. actinomycetemcomitans disappeared, while the non-JP2 types of A. actinomycetemcomitans remained a part of the oral microflora.  相似文献   
54.
55.
Chronic coinfection with hepatitis C virus (HCV) and human immunodeficiency virus (HIV) is among the greatest challenges facing public health worldwide. In this population, the response to hepatitis C therapy by treatment with pegylated interferon plus ribavirin (PEG-IFN+RBV) is lower than in HCV-monoinfected patients, particularly in those infected by HCV genotype 1. A PKR/eIF-2α phosphorylation homology domain (PePHD) within the E2 protein has been found to interact with PKR and inhibit PKR in vitro, suggesting a possible mechanism for HCV to evade the antiviral effects of IFN. The aim of this work was to analyze the amino acid conservation in the HCV-E2-PePHD and quasispecies diversity among HCV-HIV-coinfected patients exhibiting sustained virological response, non-response, or partial response with viral relapse to PEG-IFN+RBV by ultra-deep pyrosequencing. For this purpose, HCV-E2-PePHD PCR products were generated and sequenced directly for four patients with a sustained response, seven patients with no virological response, and four patients with viral relapse before and after treatment with PEG-IFN+RBV. HCV-E2-PePHD amino acid sequences were obtained for isolates from serum collected before and during treatment (24 h, 4 weeks, and 12 weeks). Quasispecies analysis of the HCV-E2-PePHD and flanking genomic regions was performed using 454/Roche pyrosequencing, analyzing 39,364 sequence reads in total. The HCV-E2-PePHD sequence at the amino acid and nucleotide level was highly conserved among HCV genotype 1 strains, irrespective of the PEG-IFN+RBV response. This high degree of amino acid conservation and sporadic mutations in the HCV-E2-PePHD domain do not appear to be associated with treatment outcome. The HCV-E2-PePHD sequence before or during treatment cannot be used to predict reliably the outcome of treatment in patients coinfected with HCV genotype 1 and HIV.  相似文献   
56.
The impact of suppressed concentrations of circulating luteinizing hormone (LH) during ovarian stimulation on the outcome of in-vitro fertilization or intracytoplasmic sperm injection treatment in 200 consecutive, normogonadotrophic women (couples) was analysed retrospectively. A standard stimulation protocol with mid-luteal gonadotrophin-releasing hormone (GnRH) agonist down-regulation and ovarian stimulation with recombinant follicle stimulating hormone (FSH) was used in all cases. Blood was sampled from each woman on stimulation days 1 and 8 for analysis of oestradiol and LH in serum. A threshold value of serum LH of 0.5 IU/l on stimulation day 8 (S8) was chosen to discriminate between women with low or 'normal' LH concentrations. Low concentrations of LH on S8 (<0.5 IU/l) were found in 49% (98/200) of the women. This group of women was comparable with the normal LH group with regard to pre-treatment clinical parameters, and to the parameters characterizing the stimulation protocol with the exception of serum oestradiol concentration, which on S8 was significantly lower than in the normal LH group (P < 0.001). The proportion of positive pregnancy tests was similar in the two groups (30% versus 34% per started cycle), but the final clinical treatment outcome was significantly different, with a five-fold higher risk of early pregnancy loss (45% versus 9%; P < 0.005) in the low LH group and consequently a significantly poorer chance of delivery than in the normal LH group. It is concluded that a substantial proportion of normogonadotrophic women treated with GnRH agonist down-regulation in combination with FSH, devoid of LH activity, experience LH suppression, which compromises the treatment outcome. Whether these women would benefit from supplementation with recombinant LH or human menopausal gonadotrophin during ovarian stimulation, remains to be proven in the future by prospective randomized trials.  相似文献   
57.
Fetal antigen 1 (FA1), an epidermal growth factor (EGF) multidomain glycoprotein, was investigated in the human reproductive system. Immunohistochemical analysis of the male reproductive system revealed staining for FA1 in the Leydig cells only. Concentrations of FA1 in seminal plasma and serum were similar and significantly correlated in weekly samples from three men (P < 0.0065). The concentrations in seminal plasma from vasectomized men (n = 4) were not significantly different from those of normal men (n = 187). The concentration of FA1 in seminal plasma was significantly correlated with the sperm counts of normozoospermic men (P < 0.0001), and significantly higher in seminal plasma from men with sperm counts > 20 x 10(6)/ml, compared with those with counts 相似文献   
58.
We investigated the development of lateral bias in infant tufted capuchins (Cebus apella) by recording head orientation during the first 2 postnatal weeks and hand preference during Weeks 23 to 24 and 47 to 48. We found that lateral bias for head orientation at 1 to 2 weeks was negatively related to hand preference at 23 to 24 weeks. Further, we found population-level left-hand preferences at both 23 to 24 and 47 to 48 weeks, and that hand preference at 23 to 24 weeks is positively correlated with hand preference at 47 to 48 weeks. We also noted a trend toward a sex difference in the direction of neonatal head orientation, with males exhibiting a left-side preference and females exhibiting a lack of preference toward either side. Our findings differ from those obtained in studies with developing humans and chimpanzees in two important ways. First, the trend for head orientation and hand preference in infant capuchins was to the left rather than to the right. Second, we found a negative relation between direction of early head orientation and subsequent hand preference. It seems likely that research examining cerebral development in capuchins will help us to better understand the occurrence of left-handedness and the development of cerebral dominance in humans. © 1998 John Wiley & Sons, Inc. Dev Psychobiol 32: 45–50, 1998  相似文献   
59.
University settings have demonstrated potential for coronavirus disease (COVID-19) outbreaks; they combine congregate living, substantial social activity, and a young population predisposed to mild illness. Using genomic and epidemiologic data, we describe a COVID-19 outbreak at the University of Wisconsin–Madison, Madison, Wisconsin, USA. During August–October 2020, a total of 3,485 students, including 856/6,162 students living in dormitories, tested positive. Case counts began rising during move-in week, August 25–31, 2020, then rose rapidly during September 1–11, 2020. The university initiated multiple prevention efforts, including quarantining 2 dormitories; a subsequent decline in cases was observed. Genomic surveillance of cases from Dane County, in which the university is located, did not find evidence of transmission from a large cluster of cases in the 2 quarantined dorms during the outbreak. Coordinated implementation of prevention measures can reduce COVID-19 spread in university settings and may limit spillover to the surrounding community.  相似文献   
60.
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