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21.
Henryk Barthel Michael Wiener Claudia Dannenberg Simone Bettin Bernhard Sattler Wolfram H. Knapp 《European journal of nuclear medicine and molecular imaging》1997,24(10):1245-1252
This study addresses the question of whether the normal range for distribution of local cerebral blood flow (lCBF) in adults
can be transferred to the 4- to 15-year-old age group. Twenty-three children (age: 4–15 years; mean 11±3 years, group I) and
10 adults (age: 27–56 years; mean 45±10 years, group II) without evidence of cerebrovascular disease or other brain diseases
underwent technetium-99m ethyl cysteinate dimer single-photon emission tomography. Counts in cortical and subcortical regions
of interest (ROIs) were related to those in cerebellar ROIs (= 100%). Relative cortical activity in group I exceeded that
in group II, particularly in left parietal (107.6%±9.8% vs 84.1%±12.4%), left frontal (97.7%±6.7% vs 79.4%±8.9%) and left
temporal areas (99.7%±7.4% vs 84.9%±10.1%) and in the cingulate cortex (112.1%±9.1% vs 95.9%±10.1%, P<0.05). Cerebral activity uptake per injected dose was inversely correlated with age in 19 children of group I (r = –0.77, P<0.001). In group I, there was also an inverse correlation between age and the relative local count density in the parietal
(r = –0.42 to –0.57), frontal (r = –0.48), temporal (r = –0.42 to –0.58) and occipital cortex (r = –0.44). In these cortical regions relative counts differed when subgroups of children aged 4–10 and 11–15 years were analysed.
It is concluded that there are systematic differences between 4- to 15-year-old children and adults with regard to normal
lCBF. Diagnostic use of perfusion agents has to consider age-adjusted normal flow maps; normal ranges should be determined
separately for the age groups 4–10 and 11–15 years.
Received 23 March and in revised form 11 July 1997 相似文献
22.
C De Simone A Misefari V Covelli A B Maffione S Antonaci E Jirillo 《Journal of clinical laboratory analysis》1989,3(6):345-349
The effects of substance P (SP) on Salmonella minnesota R345 (Rb) binding to human peripheral blood lymphocytes (PBL) were evaluated. Two parameters of bacterial cytoadherence were considered, namely the binding lymphocytes (BL) and the number of bound-bacteria/lymphocyte (BB). The results showed that SP inhibits both BL and BB in a significant manner. Furthermore, distribution of Salmonella binding to CD4+ and CD8+ lymphocytes was studied following SP pretreatment of lymphoid cells. This neuropeptide is able to hamper the bacterial cytoadherence to both T-cell subpopulations and, in particular, the inhibitory effect on the T-suppressor/cytotoxic subset was more pronounced. These findings are discussed in terms of SP intervention in the mechanism of host protection against invading microorganisms. 相似文献
23.
Munzel Peter; Bock-Hennig Barbara; Schieback Sylvia; Gschaidmeier Harald; Beck-Gschaidmeier Simone; Bock Karl Walter 《Carcinogenesis》1996,17(2):197-202
Modulation of DNA synthesis by 2,3,7,8-tetrachlorodi-benzo-p-dioxin(TCDD) was studied in primary cultures of hepatocytes and inrat liver epithelial cells (WB-F344) to develop models for studieson the interactions between the activated Ah receptor and cellulargrowth control. In hepatocytes TCDD either positively or negativelymodulated EGF-stimulated DNA synthesis. In the presence of ethlnylestradiol1012 M TCDD moderately increased EGF-stimulated DNA synthyesis( 相似文献
24.
Annalisa Volpi Francesco Bacci Angelo Paradiso Luca Saragoni Emanuela Scarpi Monica Ricci Mirella Aldi Simonetta Bianchi Pietro Muretto Fiorella Nuzzo Gianni Simone Anita Mangia Francesco Schittulli Dino Amadori 《Modern pathology》2004,17(9):1038-1044
Available results highlight the lack of good level of evidence studies on the pure prognostic value of histological grade. In the present study, the prognostic relevance of histological grade and of its three components, tubule formation, nuclear pleomorphism and mitotic count, was analyzed in a series of 372 patients with node-negative breast cancer treated with locoregional therapy alone until early relapse. Histological grade was determined blindly by two observers and discordance between evaluations was resolved after joint review using a multihead microscope. No relation was observed between histological grade and any of its three components and disease-free survival. Conversely, a significant relation was observed between histological grade and distant metastasis-free survival (at 6 years, 94, 86 and 76% for grades 1, 2 and 3, respectively, P=0.013) as well as overall survival (98, 90 and 86%, P=0.001). A breakdown analysis as a function of the three components showed that neither tubule formation nor nuclear pleomorphism was associated with prognosis, and only mitotic count strongly influenced both distant metastasis-free survival (91, 82 and 74%, P=0.014) and overall survival (97, 87 and 85%, P=0.011). Histological grade suffers from a much higher subjectivity than any other microscopic evaluation of biomarkers as it is the sum of three different morphological features. Within the Italian Network for Quality Assessment of Tumor Biomarkers program we observed that histological grade is an independent prognostic variable, but also that this role is ascribable only to the number of mitotic figures. In conclusion, due to the ever smaller size of diagnosed breast cancers, resulting in less cancer tissue for biofunctional and molecular analysis, mitotic count evaluated under strict quality control conditions seems to be an accurate and feasible prognostic variable. 相似文献
25.
26.
The octadecyl rhodamine (R18) fluorescent dequenching assay was used to examine membrane fusion between mumps virus and mammalian cells. Rapid fluorescent dequenching, indicative of membrane fusion, was observed when labeled mumps virus was mixed with either ghost erythrocytes or CV-1 cells. After 15 min a saturation limit of 18 virus per erythrocyte ghost and 6400 virus per CV-1 cell was observed. Fetuin was found to inhibit virus fusion, suggesting a role for sialic acid in virus binding to the cells. Two dequenching processes were observed of which the faster process is thought to be membrane fusion and the second process is thought to be probe proximal transfer. 相似文献
27.
Marco Montorsi Guido Torzilli Uberto Fumagalli Stefano Bona Riccardo Rosati Matilde de Simone Vittorio Rovati Franco Mosca Carlo Filice 《HPB surgery》1994,8(2):89-94
The increased use of Ultrasonography (US) has led to increased detection of simple hepatic cysts.
For symptomatic cysts treatment is necessary. Until some years ago surgery was the only
therapy. We have treated a large number of patients with Percutaneous Alcohol Sclerotherapy
(PAS) and evaluated retrospectively the efficacy of this approach.Data on 21 patients with symptomatic simple hepatic cysts were reviewed retrospectively.
Cysts had a mean diameter of 9 cm (range: 7–15 cm). PAS was always performed under local
anesthesia and US guidance. 25% of the volume was replaced with 95% ethanol and then
completely aspirated after 20–30 minutes.No complications or deaths occurred. In all patients symptoms disappeared after treatment.
In 15 out of 21 cases there was no evidence of residual cyst on US, computed tomography (CT) or
magnetic resonance (MRI). In 6 patients with shorter follow-up, cysts showed a mean reduction
in diameter of 50%. The mean follow-up was 18 months (range 6–60 months).We conclude that PAS is easy with low risk for the patients and with good long-term results; it
should therefore become the procedure of choice for simple hepatic cysts. 相似文献
28.
29.
Dr. A. Belluzzi MD C. Brignola MD M. Campieri MD E. P. Camporesi BS P. Gionchetti MD F. Rizzello MD C. Belloli MD G. De Simone MD S. Boschi MD M. Miglioli MD L. Barbara MD 《Digestive diseases and sciences》1994,39(12):2589-2594
Fish oil has been recently proposed as a possible effective treatment in inflammatory bowel disease (IBD); however, a lot of annoying side effects (ie, belching, halitosis, diarrhea, etc) affect patient compliance. We carried out a study of patient tolerance in a group of Crohn's disease (CD) patients with a new fish oil derivative consisting of 500-mg capsules of eicosapentaenoic-docosahexaenoic (EPA 40%-DHA 20%), a free fatty acid mixture (Purepa), and we also evaluated its incorporation into phospholipids, both in plasma and in red cell membranes. Five groups of 10 CD patients in remission received nine Purepa capsules daily in four different preparations (A: uncoated, B: coated, pH 5.5; C: coated, pH 5.5, 60 min time release; D: coated, pH 6.9) and 12 × 1-g capsules daily of a triglyceride preparation (Max-EPA, EPA 18%-DHA 10%), respectively. We coated three of the four Purepa preparations in order to delay the release of contents in an attempt to minimize the side effects. After six weeks of treatment, the group taking Purepa capsules, coated, pH 5.5, 60 min time release (group C) showed the best incorporation of EPA and DHA in red blood cell phospholipid membranes (EPA from 0.2 to 4.4%, DHA from 3.7 to 6.3%), and no side effects were registered, whereas in all other groups side effects were experienced in 50% or more of subjects. This new preparation will make it possible to treat patients for long periods. 相似文献
30.
Priv.-Doz. Dr. J. E. Hoppe cand. med. Simone Köster Prof. Dr. D. Niethammer Priv.-Doz. Dr. F. Bootz 《Infection》1994,22(3):178-182
Summary During recent years, a significantly increased incidence of acute mastoiditis was observed at the University Children's Hospital, Tübingen, Germany (1975–1979: 1.4 patients/year; 1987–1992: 4.2 patients/year; p<0.05). We therefore reviewed the records of all patients with acute mastoiditis (n=58) that had been treated at the Children's Hospital between 1975 and 1992 and at the Clinic of Otorhinolaryngology between 1978 and 1992. The male to female ratio was 1.8:1 and 60.4% of the patients were younger than 24 months. Retroauricular swelling was more often observed (n=49) than protrusion of the pinna (n=45) and retroauricular redness (n=38).Streptococcus pneumoniae was the most frequently isolated pathogen. Several factors predisposing for the development of acute mastoiditis were identified. These included withholding antimicrobials for treatment of the preceding episode of otitis media; use of suboptimal agents for therapy of otitis media (penicillin and, possibly, erythromycin ethylsuccinate); and insufficient duration of treatment.
Akute Mastoiditis — wieder ein aktuelles Problem
Zusammenfassung In den letzten Jahren wurde an der Univ.-Kinderklinik Tübingen eine signifikante Zunahme der Inzidenz der akuten Mastoiditis beobachtet (1975–1979: 1,4 Patienten/Jahr; 1987–1992: 4,2 Patienten/Jahr; p<0,05). Wir analysierten daher die Krankengeschichten aller Patienten mit akuter Mastoiditis (n=58), die zwischen 1975 und 1992 an der Universitäts-Kinderklinik und zwischen 1978 und 1992 an der Universitäts-Hals-Nasen-Ohrenklinik behandelt worden waren. Das Verhältnis von Jungen zu Mädchen betrug 1,8:1, und 60,4% der Patienten waren jünger als 24 Monate. Eine retroaurikuläre Schwellung wurde häufiger beobachtet (n=48) als ein abstehendes Ohr (n=45) und eine retroaurikuläre Rötung (n=38).Streptococcus pneumoniae war der häufigste Erreger. Mehrere für das Auftreten einer akuten Mastoiditis prädisponierende Faktoren wurden gefunden: die Nichtbehandlung der vorausgegangenen Otitis media mit Antibiotika, der Einsatz suboptimaler Antibiotika (Penicillin und möglicherweise Erythromycin-Ethylsuccinat) für die Otitis-Behandlung und eine ungenügende Therapiedauer.相似文献