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51.
Manfredi R Chiodo F 《Le infezioni in medicina : rivista periodica di eziologia, epidemiologia, diagnostica, clinica e terapia delle patologie infettive》2001,9(2):101-107
In order to assess the epidemiological, microbiological, and clinical features of cellulitis and soft tissue infection occurring during the course of HIV disease, clinical and laboratory data of 2221 hospitalizations carried out since 1991 were retrospectively examined, and 67 bacteriologically-proven episodes of cellulitis-soft tissue infection were identified (3.02% of overall admissions). Among the 92 cultured pathogens, Staphylococcus aureus was the most frequent (46 cases), followed by Pseudomonas spp., Escherichia coli, and Streptococcus pyogenes; 38.1% of patients had a polymicrobial infection. i.v. drug use (p<.02) and the male gender (p<.05), were significantly associated with the occurrence of these complications, while a great variation in the severity of underlying immunodeficiency was shown. An elevated rate (83.6%) of episodes of cellulitis or soft tissue infection were community-acquired in origin; the comprehensive frequency of these episodes significantly dropped during the highly active antiretroviral therapy (HAART) era (p<.01). Limbs were involved in over 80% of episodes, and an hematogenous dissemination of bacterial infection (which occurred in 25.4% of cases), proved significantly related to a CD4+ lymphocyte count <100 cells/microL (p<.03), and an absolute neutrophil count <1000 cells/microL (p<.05). S. aureus strains showed an elevated in vitro resistance rate to penicillin, ampicillin, and rifampin, and a 21.7% rate of methicillin-resistance, while among the 29 gram-negative microorganisms, resistance to ampicillin and first-generation cephalosporins, and that to amoxycillin-clavulanate and second-generation cephalosporin, occurred in over 90% and 60% of tested strains, respectively. All episodes of HIV-associated cellulitis and soft tissue infection were favorably treated in 5-16 days, in over 60% of cases with associated beta-lactam and aminoglycoside antibiotics; a recurrence of staphylococcal cellulitis occurred in 4 patients only, 6-17 months after the initial episode. Cellulitis and soft tissue infection are underestimated complications of HIV disease, but they have a broad etiological and clinical spectrum, are predominantly community-acquired, and are responsible for an appreciable morbidity, due to the supporting role of i.v. drug addiction, and the frequent hematogenous dissemination (which proved to be significantly related to the progression of immunodeficiency and underlying disease). The frequent polymicrobial etiology requires a combination antimicrobial therapy (to be guided by in vitro susceptibility studies), which may avoid a complicated and recurrent disease course in the great majority of cases. 相似文献
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53.
Paternal effects acting during the first cell cycle of human preimplantation development after ICSI.
BACKGROUND: The ability of human embryos to undergo normal development has been shown previously to be subject to strong paternal (sperm-derived) effects. This study was undertaken to determine whether paternal influences on human embryo quality are detectable as early as the first cell cycle after fertilization. METHODS: The quality of zygotes and cleaving embryos resulting from sibling donor oocytes fertilized by sperm from different patients were compared in a donor oocyte-sharing programme. RESULTS: Fertilizations with sperm from certain individuals repeatedly resulted in the formation of high proportions of zygotes with abnormal pronuclear morphology that subsequently tended to cleave slowly and to show extensive fragmentation and blastomere irregularities. This phenomenon was observed with oocytes from two different donors for each of these individuals and contrasted with normal developmental performance of embryos resulting from sibling oocytes fertilized by sperm from other men with similar basic sperm characteristics. Fertilization rates were not related to these differences. CONCLUSIONS: These data point to a very early onset of paternal effects that condition human embryo development. These effects may be both of genetic (related to the minor gene activity of the male pronucleus) or epigenetic (related to the sperm-derived oocyte-activating factor or sperm centrosome) origin. 相似文献
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55.
E DelGuercio J Greco K E Kim J Chinitz C Swartz 《The New England journal of medicine》1973,289(13):678-679
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58.
C Romano R M Ragusa F Scillato D Greco G Amato C Barletta 《American journal of medical genetics》1991,39(4):391-395
We report on mosaic 46,XY/46,XY,del(5)(p15) cri du chat syndrome. The clinical findings are compared with those compiled from a literature survey. A phoniatric evaluation was performed and compared with that of a cri du chat patient without mosaicism previously observed by the authors. 相似文献
59.
Marchini Maurizio; Manfredi Barbara; Tozzi Luca; Sacerdote Paola; Panerai Alberto; Fedele Luigi 《Human reproduction (Oxford, England)》1995,10(4):815-817
Dysmenorrhoea is a recurrent painful disease which causes physicaland psychological stress. The purpose of the present study wasto investigate whether there was a measurable derangement ofimmune cells and immune responses in women with severe primarydysmenorrhoea. On day 26 of one cycle and on days 1 and 3 ofthe following cycle we measured polyclonal, mitogen-inducedlymphocyte proliferation and -endorphin concentration in peripheralblood mononuclear cells obtained from 16 infertile women withnormal pelvis, of whom eight had and eight did not have thedisorder. In women with dysmenorrhoea, polyclonal mitogen-inducedlymphocyte proliferation was lower than in controls on all 3days considered, but the difference was statistically significantonly on day 26 (43 605 ± 9876 µg/ml versus 67 305± 15 249 µg/ml; P < 0.01). Monocyte -endorphinconcentrations in the patients with dysmenorrhoea were significantlyelevated on day 3 compared to controls (67.8 ± 24.3 pg/106cells versus 29.7 ± 6.9 pg/106 cells; P < 0.05). Ourresults demonstrate that immune responses are modified in patientswith primary dysmenorrhoea. These effects are independent ofcirculating hormone concentrations and are consistent with therole of dysmenorrhoea as a stressful event. 相似文献
60.
Savarino L Fini M Ciapetti G Cenni E Granchi D Baldini N Greco M Rizzi G Giardino R Giunti A 《Journal of biomedical materials research. Part A》2003,66(3):652-661
The concomitant influence of surface roughness and fluorhydroxyapatite (FHA) coating of titanium (Ti) implants on bone response was investigated. For this purpose, titanium screw-shaped implants with a lower degree (Y371) and a higher degree (TiPore300) of surface roughness, coated with FHA and uncoated, were transversally inserted into the diaphyses of sheep tibiae for 12 weeks. Four sheep received Y371 (group A) and Y371 + FHA (group B) screws and four sheep received TiPore300 (group C) and TiPore300 + FHA (group D) screws. For each type of material, the morphology and microstructure of implant-facing bone were evaluated. The host bone of each tibia was used as a control. In all groups the bone tissue did not reach a complete maturation. The higher degree of roughness, perhaps due to an excessive irregularity of the surface, induced the worst osteointegration: a fibrous tissue layer between screw and new bone tissue was often present. Nevertheless, as viewed by XRD, no crystallographic change of the apatite lattice was observed in any of the implants. In contrast, the microhardness value, an index of bone mineralization, was higher in the uncoated screws and decreased progressively in the following order: group C > group A > group B > group D. The association of plasma spraying with roughness treatment constitutes a complex system that seems to interfere with bone mineralization. A chemical change of the surface, perhaps with more Ti release or more coating degradation, could be responsible for such impairment. The authors emphasize the necessity for simultaneous evaluation of surface topography and chemistry as well as an improvement in plasma-spraying and post-processing techniques and in standard procedures for materials characterization. 相似文献