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81.
Oral immunoglobulin has been described as preventing necrotizing enterocolitis(NEC) in preterm infants. To prevent NEC in
extremely low birth weight infants (ELBW), we have carried out oral IgG prophylaxis since April 1991. The efficacy of this
prophylaxis was examined in a study comparing historical cohorts. ELBW infants delivered in the Department of Obstetrics and
Gynaecology of the University of Ulm and treated until day 28 in the level III intensive care nursery, Division of Neonatology,
University of Ulm were included. Cohort 1, born between 1.1.1988 and 31.3.1991, received no oral IgG and served as a control
[n=84, gestational age: median 26 weeks, range 24–34; birth weight: 811 g, 490–990], cohort 2, born between 1.4.1991 and 31.12.1995
[n=137, gestational age: 26 weeks, 22–32; birth weight: 760 g, 362–995], received 6 × 100 mg/kg human IgG (Beriglobin) orally
on days 1–28. NEC, stage 2a and higher according to the modified classification of Bell, was observed in 9 of 84 (10.7%) infants
of cohort 1 and in 11 of 137 (8%) infants of cohort 2 until day 28. The difference did not reach statistical significance
(P=0.63 Fisher's exact test).
Conclusion In this historical cohort study, ELBW infants were not protected against NEC by oral IgG. The present published evidence
does not allow recommendation of oral human IgG administration in preterm infants as a prophylactic measure against NEC.
Received: 8 June 1997 / Accepted in revised form: 1 January 1998 相似文献
82.
Guo RJ; Wang Y; Kaneko E; Wang DY; Arai H; Hanai H; Takenoshita S; Hagiwara K; Harris CC; Sugimura H 《Carcinogenesis》1998,19(9):1539-1544
Mutations in the transforming growth factor beta type II receptor
(TGFbetaRII) gene have been detected in several human cancer types
exhibiting microsatellite instability. Using intron primers previously
reported for examination of the entire coding region of the TGFbetaRII
gene, 29 sporadic gastric cancers were screened with non-radioactive single
strand conformation polymorphism and subsequent DNA sequencing analysis.
Mutations of the TGFbetaRII gene were detected in three out of 29 tumors
(10%). Two cases showed deletions in a polyadenine tract in both alleles
and was positively associated with replication error. One case had an
insertion of GA dinucleotide sequence in one allele. Mutations of the
TGFbetaRII gene were restricted to exon 3 and other coding regions were not
affected. Loss of heterozygosity was detected by analyzing a polymorphic
site in intron 2. Three out of nine (33%) informative cases, which were all
of intestinal type and advanced cases, showed loss of heterozygosity but
neither TGFbetaRII mutation nor replication error was found in these cases.
Immunoreactivity of TGFbetaRII in tumor tissues was reduced to a different
extent in the gastric cancer with genetically abnormal transforming growth
factor. Although the numbers studied are small, homozygous (A)10 deletion
or loss of heterozygosity of TGFbetaRII is involved in tumorigenesis and
progression of at least some part of sporadic gastric cancer.
相似文献
83.
84.
Lauer I Czech N Zieron J Sieg P Richter E Baehre M 《European journal of nuclear medicine》2000,27(10):1552-1556
The purpose of this study was to investigate the value of bone scintigraphy including single-photon emission tomography (SPET) and semiquantitative analysis for the assessment of graft viability following microvascularized bone transplantation. We evaluated 60 scintigraphic studies of 36 patients with 39 bone grafts. Thirty-four investigations were performed 6-11 days (early bone scans) and 26 up to 11 months (late bone scans) after mandibular reconstruction. After administration of 550 MBq technetium-99m methylene diphosphonate, planar scintigrams and a SPET study were performed. The data were reconstructed iteratively. Scans were evaluated visually and semiquantitatively by a region of interest technique using the ratio between transplant and cranium (T/C). Patients with uncomplicated healing showed a T/C ratio >1.0 in early and late bone scans. In cases with necrosis, the T/C ratio was below 1.0 when performing early bone scans. However, in late bone scans, some patients with necrosis showed a slightly increased uptake and a T/C ratio >1.0. The data demonstrate that as early as 6-11 days after mandibular reconstruction, increased tracer uptake proves that the surgery has been successful and indicates a normal healing process. Especially in the early bone scans no false-positive or false-negative results were observed and the T/C ratio clearly differentiated between vital and non-vital bone grafts. At later times false-positive findings could be observed; these were, however, rare because of the significantly higher tracer uptake of the healthy grafts when compared with completely or partially necrotic transplants. 相似文献
85.
K(ATP) channels regulate the neuronal excitability and their activation during hypoxia/ischemia protect neurons. The activation of K(ATP) channels during hypoxia is assumed to occur mainly due to the fall in intracellular ATP levels, but other intracellular signalling pathways can be also involved. We measured single K(ATP) channel currents in inspiratory brainstem neurones of neonatal mice. The activity of K(ATP) channels was enhanced in hypoosmotic bath solutions, or after applying negative pressure to the recording pipette. Cytochalasin B activated K(ATP) channels and prevented the effects of osmo-mechanical stress, indicating that cytoskeleton rearrangements, which occur during hypoxia, contribute to the activation of K(ATP) channels. During hypoxia, extracellular levels of many neurotransmitters increase, leading to activation of corresponding metabotropic receptors that can modulate K(ATP) channels. K(ATP) channels were activated by GABA(B) agonist, baclofen, by mGLUR2/3 agonists and were inhibited by mGLUR1/5 agonists. K(ATP) channels were activated by phorbol esters and were inhibited by staurosporine. These treatments did not occlude the modulating actions of mGLUR agonists, indicating that they are not mediated by protein kinase C. Activator of alpha-subunits of G-proteins Mas 7 increased and their inhibitor GPant-2 decreased the activity of K(ATP) channels. In the presence of either agent, the modulatory actions of baclofen and mGLUR agonists were not observed. We conclude that K(ATP) channels are modulated by G-proteins that are activated by metabotropic receptors for GABA and glutamate and their release during hypoxia complements activation of channels by osmo-mechanical stress and [ATP](i) depletion. 相似文献
86.
Fritzsche K Sandholzer H Werner J Brucks U Cierpka M Deter HC Härter M Höger C Richter R Schmidt B Wirsching M 《Psychotherapie, Psychosomatik, medizinische Psychologie》2000,50(6):240-246
Since 1987, psychosocial primary care (PPC) provided by General Practitioners, are reimbursed by German health insurances. The aim of the psychosocial primary care is to improve recognition and treatment of mental disorders in the primary care sector. As a part of a eight-center national demonstration program on quality management in the outpatient services, General Practitioners (n = 191) from 5 regions participated in the study. 1341 treatment episodes of patients with predominately psychosocial strain were documented. Differences between psychosocial strain, treatment and outcome were determined by analyses of variance. Men and patients beyond the age of 65 were underrepresented. Psychosocial treatments were offered more often to those patients, who had the highest level of anxiety and depression. Patients with physical illness, with pain and without psychological attribution to the illness belief were offered less psychosocial interventions and reached a worse outcome. The study outcome helps to improve training programs as to recognition and treatment of psychosocial problems in primary care. Male and generally elderly patients with somatic symptoms and lack of psychological attribution need a special psychosocial intervention to improve the outcome. 相似文献
87.
The assessment of therapists' behaviour an essential part of psychotherapy research, especially for controlling the validity of studies. In the last decade, particularly in English-speaking countries, research has been developed that studied two constructs important in this context: adherence and competence. Adherence refers to the extent to which therapists use the strategies recommended in a therapy manual; competence refers to the quality of the use of these strategies. This article is a review of research associated with adherence and competence scales and its relevance. First of all, definitions and examples of use are presented and discussed. Secondly, some of the most important scales that have been developed in this context are described. Thirdly, aspects of realisation are presented. Finally, the pros and cons of this type of research are discussed. It is argued that despite some problems adherence and competence scales are a significant contribution to the systematic assessment of therapist behaviour. 相似文献
88.
Diaphysäre Femurpseudarthrosen – nur ein technisches Problem? 总被引:2,自引:0,他引:2
Between 1981 and 1994 at the Bergmannsheil Ruhr University Hospital in Bochum, Germany, we treated 145 patients with femoral diaphyseal nonunions following initial operative treatment. Of these patients, 138 received this initial operative treatment at an outside institution. The primary reconstructions for the fractures utilized plates in 112 cases, reamed nails in 24 cases and external fixators in 9 cases. The average age of the patients was 35 years and the mean time from the initial operative treatment was 2 years. Twenty-seven patients (19%) presented with a hypertrophic nonunion and 118 (81%) with an atrophic nonunion. There was a significant correlation between primary "classic" plating and development of an atrophic nonunion (chi 2-test: P < 0.01). We observed 34 wound infections (23%) with no significant correlation to the type of primary osteosynthesis. We determined that 73 of the pseudarthroses were due to improper osteosynthesis techniques. Of these cases, 41% involved the use of plates, 83% involved the use of reamed nails, and 78% involved the use of external fixators. Fracture location near the diaphyseal-metaphyseal junctions was common in this problematic group. Ninety-two percent of all plates led to atrophic nonunions. There were 21 open fractures and of these 90% (n = 19) developed an atrophic pseudarthrosis and 29% (n = 6) developed a wound infection. Fifty-seven (39%) of all patients had additional injuries, but we found that did not increase the risk of disturbed bone healing. Our revision operations focused on the elimination of wound infections, refreshment of bone healing, and improvement in fragment stability. Only 28% of all "classic" plates and 11% of all external fixators were changed to an intramedullary implant at the time of the first revision surgery. Hypertrophic nonunions required a mean of 1.3 revision operations to achieve bone healing whereas a mean of 2 revision operations were necessary to fuse atrophic bone ends (P < 0.05). In cases of diaphyseal pseudarthrosis healing time was not affected by the type of osteosynthesis used for primary reconstructions. Since lack of fracture healing can often already be observed directly from postoperative X-rays, we recommend that revision procedures be performed early. The prolonged length of time to care for femoral nonunions underlines the importance of appropriate primary fracture treatment. That takes into consideration both the biomechanical and the biological aspects of bone healing. 相似文献
89.
Methyl mercury (MeHg) at a concentration of 20 microM significantly inhibits the synthesis of aminoacyladenylates (AAA) in vitro from serine and histidine, and fails to inhibit AAA synthesis from phenylalanine, leucine, arginine and aspartate. In vivo administration of MeHg (single i.p. injection of 50 nmol/g body weight) leads to 75-80% suppression of AAA synthesis from serine, histidine, phenylalanine, leucine, arginine and aspartate in rat brain tissue. 相似文献
90.