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1.
The purpose of the study was to attempt to replicate a finding of Persky et al. (1978) that midcycle peak values of testosterone (T) in women predicted differences in frequency of intercourse among married couples. Luteinizing hormone (LH), total testosterone (TT), and free testosterone (FT) values from 10 to 14 daily midcycle blood samples donated by 43 volunteering wives were analyzed against sexual activity patterns reported by the couples over a longer period of time. All couples were contracepting by means other than exogenous hormones or the rhythm method. Each morning through three menstrual cycles husbands and wives recorded independently and on separate forms answers to a series of questions concerning sexual activity in the previous 24 hr. Wives also recorded basal body temperatures (BBT). We designated midcycle values of TT and FT according to several definitions of midcycle. Total testosterone levels at the day of the BBT nadir and the day before the nadir correlated significantly with average intercourse frequency. Correlations with FT were statistically significant regardless of which midcycle measure was used; the day before the BBT nadir gave the highest correlation, 0.618, p = 0.01. Mean testosterone (TT or FT) values were not significantly related. We conclude that female midcycle total testosterone or free testosterone is indexing some unobserved event that affects the frequency of intercourse of couples. We speculate that this event affects the motivation of females, which influences the set point of the compromise frequency characteristic of couples.Research supported in part by NICHD Grant No. 1-R01-HDO7454-01.  相似文献   
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Croup is an acute infectious illness usually occurring in children; it is characterized by brassy cough and stridor. The main pathogens include mainly parainfluenza and influenza viruses. Recently there have been reports of prolonged croup caused by the herpes simplex viruses. We report two cases of prolonged croup due to herpes simplex types 1 and 2. We also review and summarize the reported pediatric cases of herpetic croup.  相似文献   
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The prototypical cutaneous manifestations of human parvovirus B19 (B19) infection include a petechial eruption in a glove and stocking distribution, reticular truncal erythema, and the "slapped cheek" sign. An association with connective tissue disease (CTD) stigmata has recently been made. The clinical and dermatopathologic findings in 14 patients whose skin lesions were accompanied by serological evidence of B19 infection or documentation of B19 genome in lesional skin are presented. The authors encountered skin biopsy specimens from 14 patients who presented with skin eruptions accompanied by clinical signs or serology suggestive of antecedent B19 infection. Clinical findings were correlated to the light microscopic appearance of the lesions and the presence of B19 genome in lesional skin. The study group comprised 9 women, 3 men, and 2 boys. Eruptions characteristic of fifth disease, including the slapped cheek sign, reticulated truncal erythema, and acral petechiae, were present in 3 patients, 1 of whom later developed granuloma annulare. The other patients had atypical clinical presentations comprising an asymptomatic papular eruption (2), an eruption clinically resembling Sweet's syndrome (3), myopathic dermatomyositis (DM) (2), lupus erythematosus (LE)-like syndromes (2), and lower-extremity palpable purpura (2). Skin biopsy specimens in 12 cases showed interstitial histiocytic infiltrates with piecemeal fragmentation of collagen and a mononuclear cell-predominant vascular injury pattern. Other features included an interface dermatitis, eczematous alterations, and papillary dermal edema. Lesions with features of DM or LE also showed mesenchymal mucinosis, whereas a biopsied lesion of palpable purpura showed leukocytoclastic vasculitis (LCV). Immunofluorescent testing showed a positive lupus band test (LBT) with epidermal IgG and C5b-9 decoration in 1 patient with a systemic LE-like illness, whereas the DM patients had negative LBTs and vascular C5b-9 deposition typical for DM. Skin biopsy specimens from 11 patients, including those whose presentations resembled LE and DM, were positive for B19 genome. The dermatopathology of B19 infection suggests tissue injury mediated by delayed-type hypersensitivity, by antibody-dependent cellular immunity directed at microbial antigenic targets in the epidermis and endothelium, and by circulating immune complexes in the setting of LCV. These mechanisms appear to generate a clinical and histopathological picture that recapitulates that of CTD.  相似文献   
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Primitive Neuroectodermal Tumors of the Central Nervous System   总被引:2,自引:0,他引:2  
Controversial issues relating to the pathobiology and classification of central nervous system primitive neuroectodermal tumors (PNETs) have plagued neuropathologists for more than 70 years. Hypotheses advanced in the mid-1920's have remained as fixed concepts in contemporary literature, largely consequent to repetitious support by a small number of neuropathologists despite a growing body of information discrediting these ideas from neuroembryologists, oncologists, neuroscien-tists and pathologists.
Attention has largely focused upon PNETs arising in the cerebellum (commonly known as medul-loblastomas [MBs]), because about 80% of central nervous system (CNS) PNETs originate in this site. It has been asserted that the 20% which do not are biologically different, although most individuals agree that the histological features of PNETs that occur in different sites throughout the CNS are indistinguishable from those growing in the cerebellum.
The historical aspects of this controversy are examined in the face of evidence that there is, in fact, a unique class of CNS tumors which should appropriately be regarded as primitive neuroectodermal in nature. Specifically, a number of different approaches to the problem have yielded data supporting this hypothesis. These approaches include the identification of patterns of expression among a variety of cellular antigens (demonstrated by the use of immunopathological techniques), molecular analyses of cell lines derived from these tumors, experimental production of PNETs and molecular genetic analyses.
Differences of opinion among surgeons, oncologists and radiotherapists are typically resolved by conducting cooperative studies of patients with these tumors who are diagnosed and treated at multiple centers.  相似文献   
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Cortical auditory evoked potentials (N1 wave) were studied in 24 adults (12 men, 12 women) and 20 children (12 boys, 8 girls; age: 4-8 years). In adults, this wave was recorded with maximal amplitude at frontocentral sites, peaking at about 100 ms poststimulation, whereas in children the auditory response displayed maximal amplitude at the midtemporal sites, with a positive wave at about 100 ms and a large negative wave at approximately 170 ms. Moreover, the modulatory effects of intensity on N1 amplitude were prominent at frontocentral sites in adults and at temporal sites in children. Frontocentral negative response was also recorded in children but was smaller in amplitude and longer in peak latency (around 140 ms) than in adults; responses were of greater amplitude at the frontal site than at the vertex before 6 years of age, whereas the reverse was more often found after this age. These data suggest great differences with age in the neural generators contributing to auditory evoked potentials recorded in the N1 latency range.  相似文献   
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In order to identify T cell epitopes within the Mycobacterium leprae 45-kD serine-rich antigen, we analysed responses to overlapping 17-mer peptides encompassing the whole antigen in non-exposed UK controls, Pakistani leprosy patients and tuberculosis patients in both the United Kingdom and Pakistan. This antigen has been described as M. leprae-specific, although it has a hypothetical homologue in M. tuberculosis. Human peripheral blood mononuclear cells were stimulated with peptide for 5 days and IFN-gamma measured in supernatants by ELISA. Some peptides were recognized more frequently by T cells from tuberculoid leprosy patients than those from UK controls, suggesting that such T cell epitopes might have diagnostic potential, while other peptides induced greater responses among UK control subjects. Short-term cell lines confirmed that these assays detected specific T cell recognition of these peptides. However, many tuberculosis patients also recognized these potentially specific peptides suggesting that there could be a true homologue present in M. tuberculosis.  相似文献   
9.
BackgroundWe compared cord blood antibody titers in unvaccinated pregnant women to those vaccinated with seasonal influenza vaccine during the 2nd and the 3rd trimesters.MethodsPregnant women had cord blood collected at delivery for hemagglutination inhibition assay against vaccine reference viruses: A/California/07/2009 (H1N1)pdm09, A/Switzerland/9715293/2013 (H3N2), and B/Phuket/3073/2013 (Yamagata lineage). Geometric mean titer (GMT) ratios were calculated comparing vaccinated versus unvaccinated pregnant women, and women vaccinated in the 2nd and the 3rd trimesters. Proportions of women achieving defined titers were compared using the χ2 test.ResultsOf 307 women, 190 (62%) were unvaccinated. Fifty and 67 were vaccinated during the 2nd and the 3rd trimesters, respectively. Median enrollment age was 29 years (interquartile range 24–34). Sixteen (5%) women had pre-existing conditions, but none were immunocompromised. GMT ratios comparing vaccinated and unvaccinated women were 5.90 (95% confidence interval [CI] 5.06–6.96) for influenza A/California, 5.39 (95% CI 4.18–6.08) for influenza A/Switzerland, and 5.05 (95% CI 4.43–5.85) for influenza B/Phuket. Similarly, the GMT ratios comparing the 3rd and the 2nd trimester vaccinated women were 2.90 (95% CI 2.54–3.39), 2.82 (95% CI 2.56–3.13), and 2.83 (95% CI 2.56–3.14), respectively. The proportions of women with defined titers for the three vaccine reference viruses did not differ between 2nd and 3rd trimester vaccinated women (titers ≥40: 68–92% versus 70–93%; ≥110: 32% versus 33–63%; and ≥330: 4–10% versus 3–21%).ConclusionsPregnant women vaccinated against influenza had more placental transfer of influenza antibodies to their infants than unvaccinated women. Placental transfer of antibodies was higher among those vaccinated in the 3rd trimester than in the 2nd trimester. There was no difference in the proportions of women achieving antibody titers corresponding to protection against influenza in children. Findings support the current World Health Organization’s recommendation that pregnant women may be vaccinated in either 2nd or 3rd trimester of pregnancy.  相似文献   
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