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71.
Obtaining karyotypes from human spermatozoa after microinjection into Syrian golden hamster oocytes is difficult and the hitherto reported results are unsatisfactory. This may be related to the injection and culture technique or to the high susceptibility of the hamster oocytes to undergo parthenogenetic activation or both. Therefore, we investigated the hamster oocyte-human sperm microinjection model using the following two approaches: (i) application of contemporary techniques for injection (touching the sperm tail) and culture (hamster embryo culture medium, HECM-3, 10% CO2) and (ii) omission of Ca2+ from the injection medium. Thus, in the first series of experiments, 252 hamster oocytes were injected with human spermatozoa. Among the 219 (87%) oocytes that survived the injection procedure, the mean percentages of male pronucleus formation [two pronuclei (2PN), two polar bodies (PB)], mitotic metaphase entry and sperm chromosome spreads were 41.4, 27.8 and 18.2% respectively. Analysis of the oocytes which failed to develop the male pronucleus following injection revealed that most of them had developed only the hamster female PN while the sperm nuclei were either intact or swollen (partially decondensed), indicating that failure of oocyte activation was not the likely reason for the failure of male PN formation in these oocytes. In the next series of experiments, sibling oocytes were alternately injected with spermatozoa suspended either in the regular (1.9 mM Ca2+) or Ca2+-free injection medium (experiment set 2, n=278). A significant improvement was noted in the mean percentages of oocytes with 2PN, 2PB, metaphase entry and sperm chromosome spreads in the Ca2+-free group versus the regular group (2PN, 2PB: 51 versus 36.6%, metaphase entry: 36.3 versus 26.9% and sperm chromosome spreads: 28 versus 20.4%; all P < 0.04). Thus, parthenogenetic activation appears to be one of the contributing factors for the failure of male PN formation after heterospecific hamster ICSI. From these experiments it can be concluded that application of the advanced injection and culture techniques and omission of Ca2+ from the injection medium are promising for the routine application of the hamster oocyte microinjection for karyotyping of human spermatozoa with poor fertilizing capacity.   相似文献   
72.
Hypoxia induced by low O2 pressure is responsible for several physiological and behavioral alterations. Changes in physiological systems are frequent, including inflammation and psychobiological declines such as mood and cognition worsening, resulting in increased reaction time, difficulty solving problems, reduced memory and concentration. The paper discusses the possible relationship between glutamine supplementation and worsening cognition mediated by inflammation induced by high altitude hypoxia. The paper is a narrative literature review conducted to verify the effects of glutamine supplementation on psychobiological aspects. We searched MEDLINE/PubMed and Web of Science databases and gray literature by Google Scholar for English articles. Mechanistic pathways mediated by glutamine suggest potential positive effects of its supplementation on mood and cognition, mainly its potential effect on inflammation. However, clinical studies are scarce, making any conclusions impossible. Although glutamine plays an important role and seems to mitigate inflammation, clinical studies should test this hypothesis, which will contribute to a better mood and cognition state for several people who suffer from problems mediated by hypoxia.  相似文献   
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Salmonella typhi is a flagellated, gram-negative bacillus belonging to the family Enterobacteriaceae responsible for typhoid fever, which is a prolonged bacteraemic, systemic illness with minimal, at least initially, diarrhoea. Localized infection is a not uncommon complication of salmonella septicaemia, particularly occurring in immunocompromised patients. However, salmonella localization to the skin presenting as cutaneous ulceration is regarded as a rare event. We report a unique case of such a presentation as the sole clinical manifestation of infection with S. typhi and highlight the possible salmonella aetiology for unusual cutaneous lesions in individuals coming from endemic areas.  相似文献   
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We describe a male patient with rosacea who had a 2-year history of persistent bilateral oedema of the eyelids, leading to an elephantoid condition with blepharoptosis. An upper eyelid blepharoplasty was performed, but swelling progressively recurred over a few months. Based on the case history, clinical appearance and histological findings, rosaceous lymphoedema was considered to be the diagnosis. The latter is a bilateral, solid oedema of the mid-third of the face, regarded as a rare complication of rosacea. It is thought to occur as a result of chronic inflammation and lymphatic stasis, but its exact aethiopathogenesis remains elusive. Predominant eyelid involvement, causing severe visual impairment as in our patient, is unique.  相似文献   
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Background  Dermatologists are often the first-line specialists who recognize and diagnose human immunodeficiency virus (HIV) infection because of pathognomic skin signs. It is therefore important to investigate attitudes and knowledge regarding HIV/acquired immunodeficiency syndrome (AIDS) amongst dermatological patients in order to provide information for dermatologists and to draw their attention to the issues.
Objectives  Awareness of HIV/AIDS, its prevention, and hypothetical behaviour were surveyed in dermatological outpatients.
Patients/method  The anonymous cross-sectional survey was conducted with consecutive German-speaking outpatients aged 18–65 years, who registered at the dermatological outpatient's clinic (excluding venereology, genitourinary or HIV medicine) of the University of Munich (Germany).
Results  Three hundred forty-seven (77.5%) questionnaires were accepted for analysis. Most of the patients knew about HIV incurability (89.4%), HIV transmissibility during needle sharing (95.3%), or vaginal (87.4%) and anal intercourse (79.5%), as well as about HIV prevention by condom use (97.8%), and use of single needles (76.2%). However, knowledge gaps and misconceptions were detected regarding the risk of HIV transmission during oral sex, and the efficacy of sexual fidelity and avoidance of blood transfusions in HIV prevention. The lowest knowledge level (< 50% correct answers) was detected in patients aged 50–59 years, in unemployed, divorced/widowed, and in those without or with incomplete school education.
Conclusions  Patient education about HIV/AIDS in dermatological ambulant settings should be performed differentially with regard to socio-demographic factors, and focused on the topic of oral sexual HIV transmission and on some other specific misconceptions.

Conflicts of interest


None declared.  相似文献   
80.
In this report we describe an open fracture of trapezoid and break in anterior cortex of capitate due to assault in a young adult male. Direct impact force of a sharp object to the first web space caused the above fractures. Open reduction and internal fixation of the trapezoid was carried out using Kirschner wires. Cut extensor tendons, extensor retaniculum, capsule, adductor pollicis muscle, first dorsal interosseous muscle, soft tissue and overlying skin were sutured primarily. Three months after the operation the patient has made a complete recovery. There is no similar case reported in the literature.  相似文献   
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