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71.
A report is given on a 10 year old girl with dwarfism, disturbances of metaphyseal ossification, which were localised especially in the distal metaphyses of the long bones and metaphyses of the tubular bones; the biochemical tests were normal. This girl shoewed similar radiographic changes as patients described by Vaandrager and Pena. In the authors' opinion it is a new entity, different from all hitherto known well-defined types of metaphyseal dysplasia. The eponyme Vaandrager-Pena is proposed for this rare but well defined type of metaphyseal dysplasia.
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Opioids are frequently associated with side effects such as nausea, vomiting, and pruritus. We hypothesized that a prophylactic, continuous small-dose naloxone infusion would reduce the incidence of opioid-induced side effects without affecting analgesia or opioid consumption. In this prospective, double-blind, randomized, controlled clinical trial, we studied 46 postoperative patients (M:F, 21:25), averaging 14 +/- 2.5 yr and 53 +/- 17 kg, at the start of morphine IV patient-controlled analgesia. Patients were randomized to either saline (control, n = 26) or naloxone 0.25 microg . kg(-1) . h(-1) (n = 20). We found that the incidence and severity of pruritus (77% versus 20%; P < 0.05) and nausea (70% versus 35%; P < 0.05) was significantly more frequent in the placebo group compared with the naloxone group. Morphine consumption (1.02 +/- 0.41 mg . kg(-1) . d(-1) versus 1.28 +/- 0.61 mg . kg(-1) . d(-1)), pain scores at rest (4 +/- 2 versus 3 +/- 2), and pain scores with coughing (6 +/- 2 versus 6 +/- 2) were not different. We conclude that, in children and adolescents, a small-dose naloxone infusion (0.25 microg . kg(-1) . h(-1)) can significantly reduce the incidence and severity of opioid-induced side effects without affecting opioid-induced analgesia. When initiating morphine IV patient-controlled analgesia for the treatment of moderate to severe pain, clinicians should strongly consider starting a concomitant small-dose naloxone infusion.  相似文献   
77.
The involvement of blood microvessels, representing the anatomic site of the blood-brain barrier (BBB), in brain damage induced by prenatal exposure to lipopolysaccharide (LPS) and/or valproic acid (VPA) was studied in four-week-old rats. The immunogold procedure was applied for localization at the ultrastructural level of endogenous albumin and glucose transporter (GLUT-1) in three brain regions: cerebral cortex, cerebellum and hippocampus. Four groups of rats were used: (1) untreated control, (2) prenatally VPA-treated, (3) prenatally LPS-treated, and (4) prenatally LPS- and VPA-treated. The functional state of the BBB was evaluated as follows: (a) by its tightness, i.e., permeability to blood-borne albumin, and (b) by the expression of GLUT-1 in the endothelial cells (ECs). Using morphometry, the labelling density for GLUT-1 was recorded over luminal and abluminal plasma membranes of the ECs, also providing information on their functional polarity. No extensive increase of vascular permeability and/or any considerable dysfunction of the BBB in experimental groups nos. 2 and 3 were observed, although in solitary vascular profiles, increased endocytosis or even transcytosis of albumin by ECs was noted. In experimental group no. 4, some vascular profiles showed scanty leakage (microleakage), manifested by the presence of immunosignals for albumin in the perivascular area. Although some fluctuations in the expression of GLUT-1 occurred in all experimental groups, especially in group no. 3, a most pronounced and significant diminution of the labelling density, in all three regions of the brain, was observed in group no. 4. This finding suggests the synergistic action of prenatally applied LPS and VPA that affects specific transport functions of glucose in the microvascular endothelium. The diminished or disturbed supply of glucose to selected brain regions can be one of the factors leading to previously observed behavioral disturbances in similarly treated rats.  相似文献   
78.
The authors describe a simple technique for diagnosis of tricuspid regurgitation. Red blood cells were labeled in vivo with 99mTc and 22 patients were studied with ECG-gated blood-pool imaging of the liver. A single region of interest was manually drawn around the liver and a time-activity curve obtained. The per cent change in liver counts during the cardiac cycle was found to be significantly higher in the 12 patients with tricuspid regurgitation (Group I) (mean, 4.04 +/- 1.6%; range, 1.3-21.4%) compared with the 10 controls (Group II) (mean, 0.35 +/- 0.16%; range, 0.013-1.3%) (p less than 0.05). Using a 1% change in liver counts as the criterion of a positive study, all 12 cases in Group I were diagnosed correctly, but there was one false positive in Group II; thus the sensitivity was 100% and the specificity 90%.  相似文献   
79.
Fluorescence in situ hybridization (FISH) analyses were performed on supernumerary marker chromosomes (SMCs) detected in 43,273 prenatal diagnoses over a period of 11 years, 1993-2003. A total of 42 pregnancies with SMC were identified, indicating a prevalence of one in 1032. A total of 15 SMCs were endowed with detectable euchromatin (prevalence, 1/2884), including six SMCs containing the cat eye critical region (CECR) on chromosome 22q11.21 (1/7212). De novo SMCs were found in 29 pregnancies (1/1492), including 14 euchromatic SMCs (48.2%). Follow-up studies were available for 24 cases. Nine pregnancies (37.5%) were terminated; two children (8.3%) were born with Pallister-Killian syndrome and cat eye syndrome (CES), respectively; 13 children (54.1%) showed apparently normal development. Familial SMCs were identified in 13 pregnancies (1/3328) from 11 unrelated women. They were all acrocentric. In all, 10 were heterochromatic and one was an extra der(22)t(11;22) chromosome. A total of 12 cases were available for follow-up. One pregnancy was terminated due to anhydramnios, spina bifida, and cystic-dysplastic kidneys; one child suffered from a der(22) syndrome; 10 children (83.3%) appeared unaffected. Studies for uniparental disomy were performed on seven pregnancies and revealed a case of maternal heterodisomy for chromosome 22. So far this is the largest FISH study of prenatally ascertained SMCs and the first study with detailed data on the prevalence. Findings illustrate the spectrum and clinical outcomes of prenatally diagnosed SMCs, and indicate a higher frequency of SMCs than generally assumed.  相似文献   
80.
Antibody (Ab) responses to polysaccharides (PS), such as Neisseria meningitidis group C PS (MCPS), are characterized as being thymus independent and are restricted with regard to clonotype and isotype expression. PS conjugated to proteins, e.g., MCPS coupled with tetanus toxoid or the diphtheria toxin derivative CRM197, elicit thymus-dependent responses. The present study developed a surface plasmon resonance approach to evaluate Ab responses to MCPS conjugate vaccines, including either O-acetylated (OAc+) or de-O-acetylated (OAc-) forms of the PS. The results were generally consistent with those obtained by enzyme-linked immunosorbent assay and showed that sera from mice immunized with conjugate vaccines contain Abs that bind more effectively to OAc+ and OAc- MCPS than sera from mice immunized with fixed bacteria. The data suggest a critical shared or overlapping epitope recognized by all the conjugate vaccine immune sera and strategies for assessing polyclonal Ab avidity.  相似文献   
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