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1.
A 41-year-old woman had acute hepatitis A infection complicated with severe anemia due to selective erythroblastopenia and hemolysis. A mechanism involving a cellular immune reaction is suggested. The hematological complications resolved during steroid treatment. She later developed a transient seropositive arthritis.  相似文献   
2.
In cases of moderate congenital ptosis, better lid elevation can be achieved by resection of the levator muscle through a skin incision, combined with tarsectomy and shortening of the superior tarsal muscle. The function of the levator muscle can thus be fully exploited.  相似文献   
3.
The use of direct susceptibility testing from specimens has led to the fortuitous observation that penicillin-susceptible strains have larger inhibition zones for mecillinam than do β -lactamase producers. The current study was, therefore, undertaken to test 179 Staphylococcus aureus isolates for mecillinam susceptibility by Rosco Neo-Sensitabs and to compare the results with commonly used tests for β -lactamase production, i.e. size and character of penicillin inhibition zones, chromogenic cephalosporin (nitrocefin) tests and clover leaf assays. Agreement between methods was reached for 175 of 179 strains when disregarding the results of the nitrocefin tests, 88 isolates being found susceptible and 87 being found to be β -lactamase producers. All 88 susceptible isolates had mecillinam zones of >22 mm, with the great majority being >25 mm; double zones did, however, occur. The 87 β -lactamase producers had zones <14 mm or no zones. Four isolates presenting problems in had mecillinam zones of ≤20 mm and were without tapering growth at the penicillin inhibition zone edge. In conclusion, the size of the mecillinam inhibition zone is found to be a useful supplementary test in the clinically important distinction between β -lactamase-producing and non-producing isolates of S. aureus .  相似文献   
4.
A prospective, consecutive study of the aetiology of treatment-associated diarrhoea was conducted in 25 patients with disseminated germ cell cancer treated with intensive chemotherapy. Clostridium difficile was isolated in 45% of the diarrhoea episodes, which makes this species the most important bacterial pathogen in the development of clinically significant diarrhoea in this group of immunocompromised patients.  相似文献   
5.
The development of photoreceptors and two putative neurotransmitter systems in the pineal organ and retina was studied during embryogenesis in the three-spined stickleback Gasterosteus aculeatus L. The investigation was performed by aid of immunocytochemistry using well characterized antisera to the retinal proteins alpha-transducin (TD alpha) and S-antigen (SA) (photoreceptor-markers), antisera against L-glutamic acid decarboxylase (GAD), gamma-aminobutyric acid (GABA), choline-O-acetyltransferase (ChAT) and with acetylcholinesterase (AChE) histochemistry (neurotransmitter-markers). It was possible to set up the following developmental time-table concerning the first appearance of positive immuno- and enzyme-reactive cells in the pineal organ and retina: I AChE-activity and TD alpha- and SA-immunoreactive cells in the pineal organ; II GAD- and GABA-immunoreactive cells in the pineal organ and retina; ChAT immunoreactivity and AChE activity in the retina; III hatching; IV SA-immunoreactive cells in the retina. The obtained results provide good evidence that while photoreceptor cells develop much earlier in the pineal organ than in the retina, neurons develop simultaneously in the pineal organ and retina.  相似文献   
6.
Background –  In this article, current scientific knowledge on the chronic fatigue syndrome (CFS) is reviewed. The US case definition of CFS (the CDC-definition) is most widespread in research and clinical practice. Estimates of prevalence vary from 0.2% to above 2%. The female–male ratio is approximately 3:1.
Clinical Features –  Severe fatigue is the dominating complaint; it is worsened from exertions and not substantially relieved by rest. In addition, the patients might have a varying combination of accompanying symptoms. Clinical evaluation should be based upon standardized guidelines, including an assessment of functional impairments.
Pathophysiology –  The pathophysiology should be interpreted within a biopsychosocial framework. Present knowledge suggests that certain genetic polymorphisms and personality traits might be regarded as predisposing factors, some infections and severe psychosocial stress constitute precipitating factors, whereas disturbances of immunity, skeletal muscle, cognitive abilities, endocrine control and cardiovascular homeostasis are possible perpetuating factors.
Treatment –  Cognitive behavioural therapy and graded exercise therapy are of proven value in randomized controlled trials. Several pharmaceutical measures have been explored and found to have no beneficial effect. Most patients might expect long-term improvement, but full recovery is rare; however, the prognosis is better among adolescents.  相似文献   
7.
Among 75 members of a Danish family, 12 were found with a syndrome not previously described. Clinically, the syndrome consists of low body height and rigid flat feet, with weight-bearing pain in the feet. Radiologically, the deformation of the feet is a medial synostosis between the talus and the calcaneus combined with ankle joint dysplasia. The cause of the syndrome is most probably an autosomal dominant gene with complete penetrance. No linkage was found of the gene to 18 marker genes.  相似文献   
8.
Histamine, an important inflammatory mediator in allergic diseases and asthma, has been reported to have modulator effects on T cells, suggesting that the bronchial microenvironment may regulate the function of resident T cells. We examined the effect of histamine on the release of the Th2-associated cytokines IL-4 and IL-5 and the Th1-associated cytokine IFN-γ by 30 CD4+ T cell clones from peripheral blood or bronchial biopsy of one atopic subject. Based on the IL-4/IFN-γ ratio, the clones were ascribed to the Th2 (ratio >1), Th0 (ratio 0.1 and 1) or Th1 (ratio <0.1) phenotype. Histamine inhibited IFN-γ production by Th1-like cells (P<0.02, Kruskall–Wallis), especially from bronchial biopsy, but had no effect on IL-4 release. Regarding Th0 clones, histamine inhibited IL-4 production (P<0.02) in a dose-dependent manner and slightly inhibited IFN-γ production, but had no effect on Th2-like cells. Histamine had a heterogeneous and insignificant effect on IL-5 production. The H2-receptor antagonist ranitidine completely reversed the inhibition of IL-4 and IFN-γ production, whereas the agonist dimaprit mimicked this effect. In contrast, H1- and H3-receptor agonists and antagonists had no significant effect. These data demonstrate that histamine has different effects on IL-4 and IFN-γ release by T helper cells according to their phenotype via H2-receptors. This study extends the immunomodulatory effects of histamine which may contribute to the perpetuation of airway inflammation in asthma.  相似文献   
9.
10.
OBJECTIVES: To examine factors influencing the rate of transmitted drug resistance (TDR) among seroconverters, with particular emphasis on 3 widely used genotypic drug resistance algorithms. METHODS: The study used data from CASCADE (Concerted Action on Seroconversion to AIDS and Death in Europe), a collaboration of seroconverter cohorts in Europe and Canada. Genotypic resistance data were derived within 18 months of the last seronegative test or date of laboratory evidence of acute infection and before the initiation of antiretroviral therapy. The Stanford algorithm was used to analyze each individual's nucleotide sequence. A multivariate logistic model was used to assess independent relationships between the presence of TDR and exposure category, sex, age at seroconversion, and year of seroconversion. The paper also describes 3 alternative definitions of resistance: the Stanford algorithm, the key resistance mutations defined by the International AIDS Society, and the Agence Nationale de Recherches sur le Sida (ANRS) algorithm. RESULTS: Forty-five of 438 patients (10.3%) seroconverting between 1987 and 2003 were infected with a drug-resistant HIV-1 variant. Forty patients (9.1%) showed resistance mutations to only 1 class of antiretroviral drugs, 2 (0.5%) to 2 classes, and 3 (0.7%) to 3 classes of antiretroviral therapy. It was suggested that individuals seroconverting later in calendar time were more likely to have TDR (relative risk 3.89 and 95% CI: 0.84 to 18.02, and relative risk 4.69 and 95% CI: 1.03 to 21.31, for 1996-1999 and 2000-2003, respectively, compared with pre-1996; P trend = 0.08). This trend was apparent regardless of the definition of TDR used. The total estimated proportion of individuals with TDR varied between 10.3% and 15.5% according to which definition was used. CONCLUSIONS: Evidence was found for the rise of TDR over time. A specific definition of what constitutes TDR rather than a simple list of mutations is needed.  相似文献   
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