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31.
Summary Southern hybridization of the total DNA of Agrocybe aegerita with cloned mitochondrial (mt) probes revealed a sequence homology between two distant mitochondrial restriction fragments. From the mtDNA restriction map and the distribution of restriction sites on the cross-hybridizing mitochondrial fragments, two copies of a large inverted repeated sequence (IR) of 3 kbp were located on the mitochondrial genome. These IR sequences divided the 80 kbp mtDNA into two singlecopy regions of 24 kbp (SSC) and 50 kbp (LSC). For the first time in higher fungi, this IR sequence has been shown to be involved in an intramolecular homologous recombinational event. Such a rearrangement led to an inversion of the orientation of the two unique-copy regions, without any change in mtDNA complexity. The location of the recombinational event was compared with previously reported plant and fungal mitochondrial rearrangements and the potential role of the IR sequence was discussed.  相似文献   
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Only a few studies of long-term survivors of AIDS (those who survive more than twice the median expected time) have been done but these reveal a constellation of psychological characteristics including, but not limited to, those with active coping, social support, life involvement, ability to communicate, and active collaboration with one's doctor. Another related literature consists of longitudinal studies following people infected with the HIV virus to determine whether psychological characteristics are related to disease progression. These studies have focused on coping, depression, negative expectancies and social support as predictors. This article reviews and integrates the two bodies of literature combining the variables identified into four psychosocial strategies related to longer survival with HIV/AIDS: following healthy self care; maintaining connectedness; having a sense of meaning or purpose in life; and maintaining perspective. Affect, beliefs, and behaviour are all seen as important. Biological variables, SES and psychological resources that the person brings to the situation and external stresses are seen as important variables to consider in prediction studies. The pathways through which these four strategies may operate (both psychological and biological) to impact on health are discussed. Psychological pathways include distress and behavioural disengagement, while biological pathways involve the sympathetic nervous system, neuroendocrine and immune mediation. Finally suggestions for future research are given.  相似文献   
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Lasers in Medical Science - Acne vulgaris is the most recurring skin condition in the world, causing great harm to the physical and psychological well-being of many patients. Antimicrobial...  相似文献   
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Annals of Surgical Oncology - The liver-first approach in patients with synchronous colorectal liver metastases (CRLM) has gained wide consensus but its role is still to be clarified. We aimed to...  相似文献   
37.
Myofibroma (MF) is a benign mesenchymal myofibroblast-derived tumor, which occurs most frequently in children, and rarely affects the maxilla. We reported a case of an aggressive intraosseous lesion found in the maxilla of a 9-year-old female child. Intraorally, the swelling extended from tooth 12 to 16, causing displacement of teeth 13, 14, and 15. Computed tomography revealed a large osteolytic lesion causing thinning and cortical erosion. Microscopically, the lesion showed a proliferation of spindle-shaped cells, with elongated nuclei and eosinophilic cytoplasm, arranged in interlaced fascicles. The immunohistochemical analysis revealed cytoplasmic positivity for α-SMA and HHF-35, and negativity for desmin, laminin, S-100, β-catenin, and CD34. Ki-67 was positive in 8% of tumor cells. The diagnosis was MF. Herein, we describe an additional case of central MF arising in the maxilla, including clinical, imaging, microscopical, and immunohistochemical features, as well as a review of the literature.  相似文献   
38.
Pseudoangiosarcomatous squamous cell carcinoma, also called pseudovascular, pseudoangiomatoid or adenoid pseudovascular carcinoma, is an uncommon and highly aggressive variant of squamous cell carcinoma. Histologically, it is characterized by proliferation of atypical keratinocytes with acantholysis and formation of pseudovascular spaces, forming anastomosed channels lined with neoplastic cells that invade the dermis. These cells are positive for cytokeratin and negative for vascular markers such as CD31 and CD34. There are few reports of this variant in the literature. Skin, breast, lung and vulva involvement have been described, but to the best of our knowledge, no cases involving the penis has been described. This study aims to describe the first case of angiosarcomatous squamous cell carcinoma of the penis. The patient presented with a painful lesion in the penis associated with urinary retention. Macroscopic findings exhibited an ulcerative vegetating lesion that involving the entire glans and part of the penile body, as well as infiltration of penile structures and scrotal skin. Microscopy shows atypical proliferation of sarcomatous keratinocyte pattern mimicking vascular spaces. Human papilloma virus (HPV) biomarkers and polymerase chain reaction (PCR) were all negative. Advanced penile squamous cell carcinoma with aggressive lymph node metastasis. This report presents the first case of penile pseudoangiosarcomatous squamous cell carcinoma, as an important differential diagnosis.  相似文献   
39.
BackgroundThe evaluation of immune responses to RTS,S/AS01 has traditionally focused on immunoglobulin (Ig) G antibodies that are only moderately associated with protection. The role of other antibody isotypes that could also contribute to vaccine efficacy remains unclear. Here we investigated whether RTS,S/AS01E elicits antigen-specific serum IgA antibodies to the vaccine and other malaria antigens, and we explored their association with protection.MethodsNinety-five children (age 5–17 months old at first vaccination) from the RTS,S/AS01E phase 3 clinical trial who received 3 doses of RTS,S/AS01E or a comparator vaccine were selected for IgA quantification 1 month post primary immunization. Two sites with different malaria transmission intensities (MTI) and clinical malaria cases and controls, were included. Measurements of IgA against different constructs of the circumsporozoite protein (CSP) vaccine antigen and 16 vaccine-unrelated Plasmodium falciparum antigens were performed using a quantitative suspension array assay.ResultsRTS,S vaccination induced a 1.2 to 2-fold increase in levels of serum/plasma IgA antibodies to all CSP constructs, which was not observed upon immunization with a comparator vaccine. The IgA response against 13 out of 16 vaccine-unrelated P. falciparum antigens also increased after vaccination, and levels were higher in recipients of RTS,S than in comparators. IgA levels to malaria antigens before vaccination were more elevated in the high MTI than the low MTI site. No statistically significant association of IgA with protection was found in exploratory analyses.ConclusionsRTS,S/AS01E induces IgA responses in peripheral blood against CSP vaccine antigens and other P. falciparum vaccine-unrelated antigens, similar to what we previously showed for IgG responses. Collectively, data warrant further investigation of the potential contribution of vaccine-induced IgA responses to efficacy and any possible interplay, either synergistic or antagonistic, with protective IgG, as identifying mediators of protection by RTS,S/AS01E immunization is necessary for the design of improved second-generation vaccines.Clinical trial registration: ClinicalTrials.gov: NCT008666191.  相似文献   
40.
Summary From 1982 to 1984 nine of 300 patients undergoing transluminal coronary angioplasty died. The nine coronary arteries and one saphenous aorto-coronary by-pass graft affected by angioplasty were studied by light microscopy. The following types of lesions were found, frequently in association: rupture of the plaque, circumscribed or reaching to the intimal layer or extending beyond it, dissections (fissures) between arterial layers, intra-plaque haemorrhage, plaque emboli and thrombosis. In two cases the therapeutic approach was considered to be clinically and pathologically successful; the patients survived 24 h (case 6) and forty days (case 4). Case 6 which presented recent lesions indicative of success showed, in contrast with the other non-successful cases, rupture affecting not only the initimal layer but also deeper structures of the arterial wall. There were also more extensive fissures. Case 4 which presented late alterations indicative of success showed a plaque fracture whose borders were kept apart by fibrous tissue. In conclusion, we believe that angioplasty allows the re-establishment of arterial blood flow by provoking deep intimal and medial rupture producing a small fissure between the arterial layers and a widening of the lumen; in cases with good late results these alterations cicatrize leaving a wider arterial lumen.  相似文献   
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