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Meckel's diverticulum is the most common congenital anomaly of the small intestine, occurring in about 2 % of the population. The most common complications associated with a Meckel's diverticulum include obstruction, bleeding, and inflammation (7, 9, 11, 18-20). The estimated lifetime risk of developing symptoms with a Meckel's diverticulum is 4-6 % (16), with the risks of complications decreasing with age. Stones within Meckel's diverticulum are recognized as a rare complication in the adult population (13,15). However, it has not been reported in the pediatric age group. The authors describe a 19-month-old male who presented with intermittent abdominal pain and vomiting, chronic microcytic anemia and a calcified stone in the lower abdomen, who was found to have a Meckel's enterolith.  相似文献   
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A number of studies using the repeat expansion detection (RED) technique have suggested an association between unknown large CAG/CTG repeats and schizophrenia. The polymorphic CAG/CTG repeat loci CTG18.1 and ERDA1 have been reported to account for a high proportion (approximately 90%) of the large repeats detected by RED and may therefore be responsible for the cited association. The recently described locus TGC13-7a contains a highly polymorphic CTA/TAG and CAG/CTG composite repeat, and is thus another authentic candidate. In the present investigation, each locus was analysed for association with schizophrenia in a sample of 206 patients and 219 group-matched controls. No evidence for association of CTG18.1, ERDA1 and/or TGC13-7a with schizophrenia was found. The combined data accounted for only 54% of the CAG/CTG arrays of > 40 repeats found in our previous RED analysis.  相似文献   
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Variability of skin temperature in the waking monkey   总被引:3,自引:0,他引:3  
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The activity patterns in self- and cross-reinnervated flexor digitorum longus (FDL) and soleus (SOL) muscles were examined during natural movements in awake, unrestrained cats in which electromyographic (EMG) electrodes, tendon-force gauges, and muscle-length gauges had been chronically implanted under anesthesia and aseptic conditions. Kinesiological data were recorded between 13 and 22 mo after nerve surgery. Self-reinnervated FDL and SOL muscles (i.e., FDL----FDL and SOL----SOL, respectively) exhibited locomotor activity patterns that were the same as observed in normal, unoperated FDL and SOL muscles (26). FDL----FDL muscles exhibited primarily brief bursts of activity in early swing, just after the toes had left the ground, whereas SOL----SOL muscles showed bursts of activity just before and during stance. In contrast, the cross-reinnervated muscles (both SOL----FDL and FDL----SOL) that had little or no unwanted self-reinnervation showed the patterns of activity that are associated with the innervating foreign motoneurons. That is, cross-reinnervated SOL----FDL muscles were intensely active in quadrupedal standing and, during the stance phase of stepping, producing large force transients while actively lengthening. Conversely, cross-reinnervated FDL----SOL muscles were active mainly in short bursts at the onset of the swing phase of stepping, just after the foot had left the ground. There was considerable modulation of EMG and peak force output in FDL----SOL muscles with changing speed of locomotion, whereas little modulation was evident in SOL----FDL muscles. The activity patterns in self- and cross-reinnervated FDL and SOL muscles were also recorded during scratch and paw-shaking reflexes. As in locomotion, the observed patterns were in all cases consistent with those expected for the innervating motor pool rather than the innervated muscle. Muscles that had been dually reinnervated by both the original and foreign motor pools displayed activity patterns that were a mixture of the FDL and SOL activity patterns described above. The present results demonstrate that motoneuron activation patterns remain qualitatively unaltered when their motor axons reinnervate foreign muscles. In addition, the observations permit some quantitative estimates of the degree to which cross-reinnervated muscles are subjected to patterns of motoneuron activity and to conditions of mechanical loading that are markedly different from those in the self-reinnervated or normal conditions.  相似文献   
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Molecular genetic studies have suggested a reading disability (RD, dyslexia) susceptibility locus on chromosome 15q. We have previously mapped this locus by association to the region surrounding D15S994. Very little is known about the neurobiological processes involved in RD, and therefore selecting positional candidate genes for analysis based upon function is difficult. Nevertheless we were able to identify two functional candidates based upon existing hypotheses. Both were phospholipase genes, phospholipase C beta 2 (PLCB2) and phospholipase A2, group IVB (cytosolic; PLA2G4B). D15S944 is located within PLCB2 and is 1.6 Mb from PLA2G4B. We examined each gene for association using a mixed direct and indirect association approach, a case (n = 164)/control (n = 174) sample, and a partially overlapping sample of 178 RD parent-proband trios from South Wales and England. Mutation analysis revealed 14 sequence variants in PLCB2 and 33 variants in PLA2G4B. All non-synonymous SNPs were genotyped as were SNPs across each gene with maximum distance between SNPs of 6 kb. Case-control analyses revealed modest evidence (0.01 < P < 0.05) for association between a single variant in PLCB2 and two variants in PLA2G4B. However, association was not confirmed in the family based sample. As the latter sample has previously generated replicated significant evidence for association between RD and markers/haplotypes surrounding D15S944, it should have sufficient power to detect association to variants in susceptibility gene itself. We conclude that neither gene accounts for the association signal we previously observed. As these are the only clear cut functional candidate genes in the region, identification of the putative susceptibility locus for RD on 15q will require more methodical non-hypothesis driven positional cloning approaches.  相似文献   
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