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81.
Changes in canine skeletal muscles during experimental tibial lengthening   总被引:8,自引:0,他引:8  
In 24 beagles, lengthening of the right tibia was performed by callus distraction after osteotomy and application of a ring fixator. Distraction was started at the fifth postoperative day, with a distraction rate of 0.5 mm twice per day, and ended after 25 days. A control group of six additional dogs underwent tibial osteotomy and external fixation without distraction. Twelve animals with and three animals without leg lengthening were euthanized immediately after the distraction period of 25 days (Group A); the remaining 15 dogs were euthanized after an additional consolidation phase of another 25 days (Group B). From the distracted right leg and from the left control leg the tibialis anterior muscle, extensor digitorum longus muscle, peroneus longus muscle, and gastrocnemius muscle were removed and studied by means of routine histologic, histochemical, and immunohistochemical analyses, and electron microscopic examination. The muscles of the control group showed no differences between the right and left sides. However, in the other 24 dogs of Groups A and B, the authors saw marked alterations affecting only the lengthened muscles but not the muscles of the control limbs. These changes were highly significant and included muscle fiber degeneration and regeneration, target fibers, central cores, minicores, marked endomysial and perimysial fibrosis, and atrophy of Type 1 and Type 2 fibers. In the consolidation period (Group B) fiber type grouping indicated that reinnervation had occurred. In addition, an increase in satellite cells and myoblasts and proliferation of nuclei were observed. The findings of the current study indicate that leg lengthening results not only in muscle fiber degeneration followed by regeneration and reinnervation but also in formation of new muscle tissue.  相似文献   
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83.
A novel trimethoprim resistance gene, designated dfrA20, was detected on the 11-kb plasmid pCCK154 from Pasteurella multocida. The dfrA20 gene codes for a dihydrofolate reductase of 169 amino acids. Sequence comparisons revealed that the DfrA20 protein differed distinctly from all dihydrofolate reductases known so far.  相似文献   
84.
Oxidative stress is characterized by an overweight of pro-oxidants against antioxidant forces and is associated with atherosclerosis, aging, and reproductive complications. Placenta is the major source of pro-oxidant agents, antioxidant enzyme-systems, and hormones and is able to keep the lipid peroxidation under control in normal pregnancy. As oxidation processes are increased in pregnancy, we would expect a shortening of lag phase of low density lipoprotein (LDL)-oxidation. LDL oxidation assessed by measuring conjugated diene formation is a marker for the early part of lipid peroxidation process and the balance of pro-oxidants and antioxidants influences length of lag phase. Our results show that resistance of LDL oxidation is unchanged during normal pregnancy in the second and third trimester. Only antioxidants are able to protect LDL. Estriol is an antioxidant, increases the lag-phase of LDL-oxidation in vitro, and its serum concentration raises enormous during late pregnancy. Thus the biological role of high levels of estriol during pregnancy may be part of the self-protection to limit oxidative damages.  相似文献   
85.
OBJECTIVES: The intestinal flora of breast-fed infants is generally dominated by Bifidobacteria. We aimed to investigate whether an infant formula supplemented with galacto-oligosaccharides and fructo-oligosaccharides (GOS/FOS) is able to establish a bifido-dominant microflora, not only in numbers but also with respect to the metabolic activity in the colon. METHODS: Two groups of infants fed infant formula with 0.8 g/100 ml GOS/FOS in a ratio of 9:1 (OSF group), or control formula (SF group) were evaluated in a randomised, double blind, placebo controlled intervention study. A breast-fed group was studied in parallel. At study onset and after 4 and 6 weeks, faecal samples were examined for the number of bifidobacteria, pH, short chain fatty acids and lactate. RESULTS: After 6 weeks, the mean proportion of bifidobacteria was significantly higher in the OSF group (59.6% versus 49.5% in the SF group; P < 0.05). Compared with controls, infants in the OSF group had a lower stool mean pH and an increased proportion of acetate and a decreased proportion of propionate. The mean pH in the OSF and SF groups were 5.7 and 6.3, respectively (P < 0.001). CONCLUSIONS: The addition of the prebiotic GOS/FOS mixture to an infant formula has a stimulating effect on the growth of bifidobacteria and on the metabolic activity of the total intestinal flora. The changes in short chain fatty acids, lactate and pH in the prebiotic group represent a fermentation profile that is closer to that observed in breast-fed infants compared to infants fed control formula.  相似文献   
86.
This review summarizes the literature on pathological buying published during the past 15 years. Pathological or compulsive buying is defined as frequent preoccupation with buying or impulses to buy that are experienced as irresistible, intrusive, and/or senseless. The buying behavior causes marked distress, interferes with social functioning, and often results in financial problems. Studies on the phenomenology, diagnosis, classification, comorbidity, epidemiology, and treatment are presented. Pathological buying should be diagnosed as impulse control disorder not otherwise specified (ICD-10 F63.9). Psychiatric comorbidity is frequent, particulary mood, anxiety, substance use, eating, impulse control and obsessive-compulsive disorders. The positive results of pharmacological treatment with antidepressants (usually SSRI) and opioid antagonists could not be confirmed in controlled trials. A disorder specific cognitive-behavioral group treatment manual was published in USA. A controlled study is currently conducted in USA and since 2003 at the Department of Psychosomatics and Psychotherapy at the University Hospital Erlangen.  相似文献   
87.
In the field of paediatric health care, measures based on consequences of health conditions have been recently developed to screen for children with special health care needs. These tools have been primarily used in survey research. The aim of this cross-sectional clinical study is to test the performance of a screener for identifying children with special health care needs (CSHCN) in a population of children with chronic conditions diagnosed and treated in different European paediatric hospitals. In the current study, the screener was employed in a sample of children with different chronic conditions (asthma, arthritis, dermatitis, epilepsy, cystic fibrosis, diabetes and cerebral palsy) across seven European countries; 456 parents of children, aged 4-7, 8-12, and 13-16 years, responded to the screener items. The study included a range of clinical measures to assess the severity of the conditions as well measures on functional health status. The prevalence of children identified positively with the CSHCN screener was 80%, which was higher than in survey estimates in the United States. Considerable variation in the screener classification was found between chronic conditions with cystic fibrosis and epilepsy showing higher rates, and skin conditions lower rates. There was no significant relationship between the screener classification and functional limitation. Findings of this study support in general the validity of the children with special health care needs screener, which shows, however, a differential validity across specific conditions. Several clinical and theoretical explanations for the lack of identifying some children with chronic conditions and the considerable variation between the conditions are discussed.Abbreviations CSHCN questionnaire for identifying children with special health care needs - FSII-(R) functional status II-(R) short form - QUICCC-R questionnaire for identifying children with special health care needs revised Funded by the European Commission, the DISABKIDS project is a cross-national effort to develop standardised instruments of health-related quality of life and needs in children and adolescents with chronic conditions. DISABKIDS international co-ordinator in chief: Monika Bullinger, Department of Medical Psychology, University Hospital of Hamburg, Martinistrasse 52, 20246 Hamburg, contract number: QLG-CT-2000-00716. Study centre: Silke Schmidt, Corinna Petersen; collaborating investigators: Hendrik Koopmann, Rolanda Baars, Department of Paediatrics, Leiden University Medical Centre, Netherlands; Peter Hoare, Hospital for Sick Children, University of Edinburgh, United Kingdom; Mick Power, Clare Atherton, Department of Psychiatry, University of Edinburgh, United Kingdom, Marie Claude Simeoni, Department of Public Health, University Hospital of Marseilles, France; John Tsanakas, Elpis Hatziagorou, Paraskevi Karagianni, University Paediatric Clinic, Athanasios Vidalis, Department of Psychiatry, Hippocratio Hospital, Thessaloniki, Greece, John Eric Chaplin, Department of Paediatrics, University Hospital Lund, Sweden; Michael Quittan, Rima Nourafza, Othmar Schuhfried, Department of Physical Medicine and Rehabilitation, University of Vienna, Austria; Ute Thyen, Esther Müller-Godeffroy, Department of Paediatrics, Medical University of Lübeck, Germany.  相似文献   
88.
The multiple intraluminal impedance (MII) technique is a new method that allows pH-independent gastroesophageal reflux detection via changes in impedance caused by a liquid bolus inside the esophagus. We wanted to know whether this technique yields objective and reproducible results. Twenty 3- to 6-hour recordings of MII from 19 preterm infants (median gestational age at birth 30 weeks, range 24-34 weeks; age at study 26 days, range 13-93 days) were divided into 23-second segments and analyzed for reflux episodes by three investigators; one investigator analyzed the data set twice. Observer agreement was assessed using kappa statistics. Each investigator analyzed 16,627 23-second segments, with a median of 854 (range 486-979) segments per recording. Median kappa values for the 20 recordings were 0.79, 0.83, and 0.83 for the three pairs of investigators and 0.84 for the repeated scoring procedure. MII recordings could be analyzed with a high level of inter- and intraobserver agreement.  相似文献   
89.
The Staphylococcus lentus plasmid pSCFS2 carries a novel florfenicol-chloramphenicol resistance gene, designated fexA, encoding a protein of 475 amino acids with 14 transmembrane domains. The FexA protein differs from all previously known proteins involved in the efflux of chloramphenicol and florfenicol. Induction of fexA expression by chloramphenicol and florfenicol occurs via translational attenuation.  相似文献   
90.
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