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Gonadal steroid levels were determined in the ovary ofSalamandra salamandra infraimmaculataduring the reproductive cycle in populations from a xeric region in northern Israel. Varying proportions of previtellogenic and vitellogenic oocytes were present throughout the year, and mature oocytes were present in winter and spring. The numbers of mature oocytes were greater between December and April, after parturition. The levels of 17β-estradiol and testosterone rose during oocyte vitellogenesis and maturation. Levels of progesterone and 17α-hydroxy progesterone appeared to be related to the level of vitellogenesis. Gravid females contained greater quantities of all four steroids than did nongravid females.  相似文献   
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BALB/c mice with pulmonary tuberculosis (TB) develop a T helper cell type 1 that temporarily controls bacterial growth. Bacterial proliferation increases, accompanied by decreasing expression of interferon (IFN)‐γ, tumour necrosis factor (TNF)‐α and inducible nitric oxide synthase (iNOS). Activation of dendritic cells (DCs) is delayed. Intratracheal administration of only one dose of recombinant adenoviruses encoding granulocyte–macrophage colony‐stimulating factor (AdGM‐CSF) 1 day before Mycobacterium tuberculosis (Mtb) infection produced a significant decrease of pulmonary bacterial loads, higher activated DCs and increased expression of TNF‐α, IFN‐γ and iNOS. When AdGM‐CSF was given in female mice B6D2F1 (C57BL/6J X DBA/2J) infected with a low Mtb dose to induce chronic infection similar to latent infection and corticosterone was used to induce reactivation, a very low bacilli burden in lungs was detected, and the same effect was observed in healthy mice co‐housed with mice infected with mild and highly virulent bacteria in a model of transmissibility. Thus, GM‐CSF is a significant cytokine in the immune protection against Mtb and gene therapy with AdGM‐CSF increased protective immunity when administered in a single dose 1 day before Mtb infection in a model of progressive disease, and when used to prevent reactivation of latent infection or transmission.  相似文献   
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Infections with hepatitis C virus, (HCV), hepatitis B virus (HBV), and human T lymphotropic type I/II (HTLV-I/II) virus are commonly found in patients infected with human immunodeficiency virus type 1 (HIV-1). We conducted a seroepidemiologic study among 174 HIV-positive heterosexuals in Buenos Aires, Argentina in 1999. Evidence of exposure to HCV, HBV, and HTLV-I/II was found in 32%, 17%, and 5%, respectively. A higher prevalence of HBV infection was observed among males (33%) compared with females (12%; P < 0.05). Among women, a prior history of a sexually transmitted infection, injecting drug use (IDU), having had more than five lifetime sex partners, and having exchanged sex-for-goods were significantly associated with HCV infection, whereas an IDU history, syringe sharing, and having exchanged sex-for-goods were found to be associated with HBV infection. Among men, an IDU history and syringe/needle sharing were significantly associated with HCV infection. The IDU-related and sexual transmission of hepatitis viruses constitute a significant problem among young, HIV-infected, heterosexuals in Argentina.  相似文献   
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BACKGROUND: Leprosy is an infectious disease with two polar forms, tuberculoid leprosy (TL) and lepromatous leprosy (LL), which are dominated by T-helper (Th) 1 and Th2 cells, respectively. High concentrations of prostaglandin E2 produced by the inducible enzyme cyclooxygenase type 2 (COX-2) in LL could inhibit Th1 cytokine production, contributing to T-cell anergy. OBJECTIVES: To compare the COX-2 expression in LL and TL. METHODS: Skin biopsies from 40 leprosy patients (LL, n = 20; TL, n = 20) were used to determine by immunohistochemistry and automated morphometry the percentage of COX-2 immunostained cells. RESULTS: Most COX-2-positive cells were macrophages; their percentages in the inflammatory infiltrate located in the papillary dermis, reticular dermis and periadnexally were significantly higher in LL than TL (P < 0.001 by Student's t-test). CONCLUSIONS: The high expression of COX-2 in LL may be related to high prostaglandin production contributing to T-cell anergy.  相似文献   
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Bilateral sudden deafness is uncommon and characterized by an acute sensorineural hearing loss in both ears of 30 dB or more in 3 consecutive frequencies. We report the case of a 57 yeras old female with this diagnosis who presented a right anacusia and a severe audiometric loss on left ear without vestibular pathology associated. She was admitted and treated by the protocol of medical therapy that we have performed in our E.N.T. Department (4 days EV and then 10 ones oral medication) with improvement in her audition 25-30 dB average. If sudden bilateral sensorineural deafnes is founded, we must consider an immuno-mediated inner ear disease (IMIED).  相似文献   
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