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31.
A series of 227 consecutive laparoscopies performed over 3 years at a provincial hospital in the North Solomons Province is presented. There were no deaths due to the procedure and morbidity was 2.4%. Positive findings were revealed in 89% of patients, allowing rapid decisions to be made regarding patient management: a vital consideration in a busy surgical unit with limited resources. Laparoscopy provides an efficient, safe, rapid and direct approach to many abdominal problems encountered in general surgery, particularly liver disease, blunt abdominal trauma, intraperitoneal infection and neoplasia.  相似文献   
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The exact opioid-sensitive receptors participating in EtOH-seeking behaviors remains unclear. Previous studies have reported higher densities of micro-opioid receptor binding in the nucleus accumbens (NACC) of P relative to NP rats; however, no differences were seen in delta-receptor binding. In contrast to the NACC, substantially lower levels of micro-receptor binding have been observed in the ventral tegmental area (VTA) of both P and NP rats, albeit no line differences have been observed. In the present study, opioid receptors in the NACC, VTA, and hippocampus were evaluated for their capacity to regulate both EtOH- and saccharin-motivated behaviors in the genetically selected alcohol-preferring (P) rat. To accomplish this, nalmefene, an opiate antagonist with preferential binding affinity for the micro-opioid receptor was unilaterally or bilaterally infused during concurrent availability of 1 h daily EtOH (10% v/v) and saccharin (0.025 or 0.050% w/v) solutions. Rats performed under a two-lever fixed ratio (FR) schedule in which four responses on one lever produced the EtOH solution, and four on a second lever produced the saccharin solution. The results demonstrated that when responding maintained by both EtOH and saccharin are matched at basal levels, unilateral (1-60 microg) or bilateral (0.5-10 microg) microinjections of nalmefene into the NACC produced selective dose-dependent reductions on responding maintained by EtOH. Unilateral (40, 60 microg) and bilateral (10 microg) VTA infusions were also observed to selectively reduced EtOH responding; however, greater nalmefene doses were required and the magnitude of suppression on EtOH responding was markedly less compared with the NACC. The greater sensitivity of nalmefene to suppress EtOH responding in the NACC is likely due to the greater number of opioid receptors in the NACC relative to the VTA. Only bilateral infusion of the 40 microg dose in the NACC and VTA suppressed responding maintained by both EtOH and saccharin. In contrast, intrahippocampal infusions dose dependently suppressed EtOH- and saccharin-maintained responding over a range of doses (1-20 microg). The present study provides evidence that nalmefene suppresses EtOH-motivated behaviors via blockade of opioid receptors within the NACC and VTA, and under various dose conditions both reinforcer and neuroanatomical specificity can be observed.  相似文献   
34.
OBJECTIVE: The purpose of the present study was to investigate the cerebral correlates of varying ages of emotional memories using quantitative electroencephalography. BACKGROUND: Recollection of emotional memories has often been used as a method of inducing emotional arousal in studies seeking to investigate the cerebral correlates of emotional arousal. However, the specific effects of the ages of the memories recalled on resulting changes in cerebral activity have not been investigated. METHOD: A total of 16 female undergraduates were asked to recollect an angry memory while quantitative electroencephalography was recorded. Following recollection, they were further asked to indicate the age of the memory recalled. RESULTS: The results indicated that significant correlations existed between ages of angry memories and changes in the magnitude of low beta (13 to 21 Hz) and high beta (21 to 32 Hz) at the right frontal, left temporal, and bilateral parietal regions of the brain. CONCLUSIONS: The results support an integration of the spreading activation and parallel distributed processing models of memory in predicting the cerebral effects of varying ages of emotional memories. Further, given the present findings, it may be important for investigators to determine the ages of the memories recalled so as to control or otherwise account for the effects of this potentially confounding variable.  相似文献   
35.
36.
Regulation of calcium levels in brain tissue from adult and aged rats.   总被引:4,自引:0,他引:4  
The possibility that regulation of Ca2+ levels in brain nerve terminals is altered as the brain ages was examined in synaptosomes from adult and aged Fischer 344 rats. Free intrasynaptosomal [Ca2+]i was monitored with fura-2 as synaptosomes were depolarized with KCl, veratridine and ibotenic acid. With all three depolarizing agents, synaptosomes from aged animals reached higher free Ca2+ levels, and the maximal Ca2+ increases (delta Ca2+) estimated from computer assisted-fitting of the curves, ranged from 35% to 80% greater in synaptosomes from aged animals. The total Ca2+ content of the brain and of synaptosomes was also found to be considerably higher in aged than in adult animals. These results suggest that the aging process in brain is accompanied by alterations in both dynamic aspects of Ca2+ handling in nerve endings and the overall content of Ca2+ in the brain and synaptic terminals.  相似文献   
37.
Cartilage sulfation (somatomedin) inhibitors (CSI) from rat liver produce reversible inhibition of cartilage growth. After gel filtration Sephadex G-200, CSI appear to have MW approximately 100,000 and they are urea- and trypsin-labile factors. To explore further the mechanism of CSI action, we used the chick pelvic rudiment bioassay and studied the effect of CSI on the incorporation on 35S-sulfate (proteoglycan synthesis), 14C-leucine (protein synthesis), 3H-uridine (RNA synthesis), and 3H-thymidine (DNA synthesis). Normal rat serum (NRS) significantly stimulated the incorporation of all four isotopes, as expected. After a 24-hour incubation, CSI significantly blunted cartilage stimulation by NRS regarding total isotope uptake (1), 35S-sulfate (NRS, 96 +/- 8 mcg/100 mg cartilage dry weight; NRS + CSI, 48 +/- 4, mean +/- SEM, n = 29, P less than .05); and (2) 14C-leucine (NRS, 2,089 +/- 172 cpm/mg dry weight; NRS + CSI, 1,102 +/- 141, n = 18, P less than .05); and (3) 3H-uridine (NRS, 6,711 +/- 832 cpm/mg; NRS + CSI, 3,227 +/- 425 cpm/mg, n = 18, P less than .05); but not (4) 3H-thymidine (NRS, 3,540 +/- 620 cpm/mg; NRS + CSI 3,249 +/- 285, n = 19). The inhibition of 35S-sulfate and 14C-leucine uptake by CSI was dose-dependent and reversible. For 35S-sulfate, uptake by cartilage incubated with CSI alone for 40 hours was 13 +/- 3 micrograms/100 mg; with CSI for 16 hours then fresh medium with NRS for 24 hours uptake was 39 +/- 12, P less than .05.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
38.
Although recent clinical case presentations suggest that diabetes does not predispose free tissue transfers to increased risk of failure, this remains an open question. The present study used a syngeneic rat strain (Lewis) for free groin flap transplantations between normal rats and streptozotocin-induced diabetic rats (2 months' duration of symptoms), to investigate the influence of diabetes on flap transfer. Flap survival at 1 week, vascular patency, flap histology and ultrastructure, and scanning electron microscopy of anastomotic sites and of corrosion casts of flap vasculature were used as bases for comparison. No differences were found in comparisons of flap survival between any groups of transfer combinations (normal flap onto normal recipient, diabetic flap onto normal recipient, normal flap onto diabetic recipient, and diabetic flap onto diabetic recipient); 100% success was achieved in each group. No differences were found in histology or corrosion casts. Transmission electron microscopy revealed a thickening of the capillary basement membrane in rat diabetic skin after only 8 weeks of symptoms. This ultrastructural finding is consistent with similar capillary basement membrane thickening seen in many other tissues of short- and long-term diabetic animals and humans. Re-endothelialization across the arterial anastomosis at 2 weeks postoperatively was significantly faster in normal versus diabetic animals (p less than 0.05). The predominantly negative findings of this study support the application of free flap transfers in diabetic patients. It is concluded that reconstructive efforts involving free tissue transfer may not be contraindicated in diabetic patients.  相似文献   
39.
The coat protein open reading frame (ORF) sequence of Helenium virus S (HelVS) was cloned and expressed in E. coli, rabbit reticulocyte and transgenic tobacco. In E. coli the size of the protein was identical to that obtained for the coat protein from purified virus particles and less than that predicted for the fusion protein. This may be due to ribosome binding at a potential ribosome binding site present on the viral sequence, approximately 45 nucleotides upstream from the initiating methionine of the coat protein ORF. This region of HelVS, equivalent to the 1.5 kb subgenomic RNA, also produced high levels of protein when transcribed and translated in vitro. When introduced into Nicotiana tabacum by leaf disk transformation via Agrobacterium tumefaciens, high levels of stable coat protein were detected which were identical in molecular weight to that of HelVS coat protein and constituted approximately 0.1-0.5% of the total extracted protein.  相似文献   
40.
Cricket fast bowlers are the potent strike force in a multidiscipline team. They subject their spines to repetitive sagittal plane and rotatory movements over many years. The effect of this repetitive stress has not previously been analysed. This study examined 20 former fast bowlers to determine the incidence of spondylolysis, spondylolisthesis and degenerative change. Fast bowlers are noted to have an increased incidence of spondylolysis. A mixed front/side bowling style involving more lumbar hyperextension or rotation has significant association with spondylolysis when compared with side-on bowling styles. There was a high incidence of radiological thoracolumbar degenerative facet joint and disc disease in former fast bowlers.  相似文献   
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