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排序方式: 共有1730条查询结果,搜索用时 15 毫秒
121.
EP Souza Neto PG Durand F Sassolas C Vial JJ Lehot 《Canadian Metallurgical Quarterly》1998,42(7):876-879
The arm is particularly vulnerable to neurological injury, due to the intimate anatomical relationship between the brachial plexus and the traction zones. Severe injuries of the brachial plexus can be caused by compression, traction or laceration. Fortunately, many deficits are superficial and permanent neurovascular deficits are rare. Nevertheless, it is important to identify the probable cause of the injury since the prognosis for recovery directly depends on the underlying nature of the neurological deficit. Two anaesthetised children who suffered brachial plexus injury during cardiac catheterisation are reported. The first, with Ebstein's anomaly and significant pulmonary valve stenosis, presented, after the procedure, with a right arm motor deficit with proximal predominance. The second patient, with tetralogy of Fallot and pulmonary atresia, presented difficulty in left arm abduction and external rotation on awakening. The risk factors for brachial plexus lesions during anaesthesia are discussed. These include improper positioning, anaesthetic agents, extreme variations of body mass index and anatomical anomalies. Prevention, evolution and treatment of the brachial plexus injury are also considered. With proper care by the cardio-radiologist and anaesthesiologist the frequency of this injury can be reduced. 相似文献
122.
M Ballal Baby A Chandran M Mathew PG Shivananda 《Canadian Metallurgical Quarterly》1998,41(4):453-456
An 8-year-old girl presented with marked shortening of the right forearm due to destruction of both the radius and ulna secondary to neonatal osteomyelitis. A one-bone forearm operation was performed to achieve a stable forearm. Two years later, the one-bone forearm was lengthened for 6 months by callus distraction (callotasis) achieving 12 cm of extra length. The patient was last followed up at the age of 16. The appearance and functional outcome of the right upper limb had been improved and she was independent in all activities of daily living. 相似文献
123.
In hippocampal neurons, neurotransmitter release can be regulated by protein kinase A (PKA) through a direct action on the secretory machinery. To identify the site of PKA modulation, we have taken advantage of the ability of the neurotoxin Botulinum A to cleave the synaptic protein SNAP-25. Cleavage of this protein decreases the Ca2+ responsiveness of the secretory machinery by partially uncoupling Ca2+-sensing from fusion per se. This is expressed as a shift toward higher Ca2+ levels of the Ca2+ to neurotransmitter release relationship and as a perturbation of synaptic delay under conditions where secretion induced by the Ca2+-independent secretagogue ruthenium red is unimpaired. We find that SNAP-25 cleavage also perturbs PKA-dependent modulation of secretion; facilitation of ruthenium red-evoked neurotransmitter release by the adenylyl cyclase activator forskolin is blocked completely after Botulinum toxin A action. Together with our observation that forskolin modifies the Ca2+ to neurotransmitter release relationship, our results suggest that SNAP-25 acts as a functional linker between Ca2+ detection and fusion and that PKA modulates an early step in the secretory machinery related to calcium sensing to facilitate synaptic transmission. 相似文献
124.
MA Richerson PG Ambrose R Quintiliani CH Nightingale 《Canadian Metallurgical Quarterly》1998,62(3):165-169
The duplicative mutation of an Ala-Val-Arg sequence at positions 208 to 210 in the loop structure of Enterobacter cloacae class C beta-lactamase caused substrate specificity extension to oxyimino beta-lactam antibiotics and this chromosomal mutation provided bacterial cells with high resistance to the beta-lactams (M. Nukaga et al, 1995, J. Biol. Chem. 270, 5729-5735). In order to confirm the universality of this phenomenon among other class C beta-lactamases, the duplicative mutation was applied to a class C beta-lactamase of Citrobacter freundii, which has 74% homology to the E. cloacae beta-lactamase amino acid sequence. The counterpart sequence to the Ala-Val-Arg of the E. cloacae enzyme in C. freundii beta-lactamase was identified to be Pro-Val-His. A Pro-Val-His sequence was inserted just after the native Pro-Val-His sequence at positions 208 to 210 in the C. freundii beta-lactamase. The resulting mutant of C. freundii beta-lactamase obtained a striking characteristic that we expected, showing substrate specificity extension to oxyimino beta-lactams. Nearly the same result was obtained with the insertion of an Ala-Val-Arg sequence after the native Pro-Val-His sequence. These results indicate that structural modification of this locus commonly induces modification of the substrate specificity to unfavorable substrates for many chromosomal class C beta-lactamases produced by gram-negative bacteria. 相似文献
125.
Though described in 1769, the etiology of Zenker's diverticulum remains unclear. Various primary esophageal motor disorders have been proposed, but no consistent manometric pattern or anatomic etiology has been uniformly recognized. An association with clinical neurologic disease at our institution prompted a review of 12 cases of Zenker's diverticulum in patients over 60 years of age, treated in the last 8 years. Nine patients (75%) underwent cricopharyngeus myotomy and diverticulectomy, with uniformly good results. Ten patients (83%) had an associated neurologic disorder, substantiated by cranial CT or MRI, in most cases. A wide range of neurologic problems were identified, but a strong trend toward brainstem or basilar lesions was present. As expected, the etiology of the neurologic abnormality in most patients in this group was cerebrovascular disease, but two patients had peripheral neuropathies. We suggest that the etiology of Zenker's diverticulum in the elderly may be neurologic in origin. Esophageal motor disorders, including incomplete upper esophageal sphincter opening and increased hypopharyngeal pressures, which may result in Zenker's diverticulum, may be a manifestation of central or peripheral neurologic disease in the elderly. 相似文献
126.
K Micha?lsson JA Baron BY Farahmand O Johnell C Magnusson PG Persson I Persson S Ljunghall 《Canadian Metallurgical Quarterly》1998,316(7148):1858-1863
OBJECTIVE: To determine the relative risk of hip fracture associated with postmenopausal hormone replacement therapy including the effect of duration and recency of treatment, the addition of progestins, route of administration, and dose. DESIGN: Population based case-control study. Setting: Six counties in Sweden. SUBJECTS: 1327 women aged 50-81 years with hip fracture and 3262 randomly selected controls. MAIN OUTCOME MEASURE: Use of hormone replacement therapy. RESULTS: Compared with women who had never used hormone replacement therapy, current users had an odds ratio of 0.35 (95 % confidence interval 0.24 to 0.53) for hip fracture and former users had an odds ratio of 0.76 (0.57 to 1.01). For every year of therapy, the overall risk decreased by 6% (3% to 9%): 4% (1% to 8%) for regimens without progestin and 11% (6% to 16%) for those with progestin. Last use between one and five years previously, with a duration of use more than five years, was associated with an odds ratio of 0.27 (0.08 to 0.94). After five years without hormone replacement therapy the protective effect was substantially diminished (-7% to 48%). With current use, an initiation of therapy nine or more years after the menopause gave equally strong reduction in risk for hip fracture as an earlier start. Oestrogen treatment with skin patches gave similar risk estimates as oral regimens. CONCLUSIONS: Recent use of hormone replacement therapy is required for optimum fracture protection, but therapy can be started several years after the menopause. The protective effect increases with duration of use, and an oestrogen-sparing effect is achieved when progestins are included in the regimen. 相似文献
127.
DH Biesma PJ Bronkhorst PG de Groot A van de Wiel RJ Kraaijenhagen JJ Marx 《Canadian Metallurgical Quarterly》1994,124(1):42-47
We report three cases of Castleman's disease mimicking the features of collagen disease. Case 1: A 39-year-old woman presented with intermittent arthralgia and fever. Laboratory findings were positive results for antinuclear antibody (80x speckled type), the LE test, anti-SSA antibody, anti-RNP antibody, and Coombs test. The patient was suspected to have systemic lupus erythematosus (SLE) or Sj?gren syndrome, but a lymph node biopsy revealed the plasma cell type of Castleman's disease. Steroid treatment led to resolution of her symptoms. Case 2: A 60-year-old man with mixed type Castleman's disease had proteinuria with renal dysfunction, autoimmune thrombocytopenia, antinuclear antibody, anti-RNP antibody, anti-DNA antibody and anti-cardiolipin antibody. The patient was suspected to have SLE but cervical lymph node biopsy revealed the mixed type of Castleman's disease. Symptoms were not controlled with steroid therapy. He developed renal failure that required for hemodialysis and died of gastrointestinal bleeding due to severe thrombocytopenia. Case 3: A 46-year-old woman had Raynaud's phenomenon, sclerodactylia, and nail fold bleeding. Laboratory tests were revealed positive for antinuclear antibody, anti-ENA antibody, and LE cell preparation. Radiographic study showed multiple masses in the retroperitoneal spaces, which necessitated laparotomy. Firstly, the patient was suspected to have systemic sclerosis or mixed connective tissue disease (MCTD). A biopsy revealed the hyaline-vascular type of Castleman's disease. The serum level of IL-6 by ELISA was high in all of three cases. In case 1, symptoms improved and the IL-6 level normalized after steroid treatment.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
128.
EE Brooks NS Gray A Joly SS Kerwar R Lum RL Mackman TC Norman J Rosete M Rowe SR Schow PG Schultz X Wang MM Wick D Shiffman 《Canadian Metallurgical Quarterly》1997,272(46):29207-29211
The activity of cyclin-dependent kinase 2 (CDK2) is essential for progression of cells from G1 to the S phase of the mammalian cell cycle. CVT-313 is a potent CDK2 inhibitor, which was identified from a purine analog library with an IC50 of 0.5 microM in vitro. Inhibition was competitive with respect to ATP (Ki = 95 nM), and selective CVT-313 had no effect on other, nonrelated ATP-dependent serine/threonine kinases. When added to CDK1 or CDK4, a 8.5- and 430-fold higher concentration of CVT-313 was required for half-maximal inhibition of the enzyme activity. In cells exposed to CVT-313, hyperphosphorylation of the retinoblastoma gene product was inhibited, and progression through the cell cycle was arrested at the G1/S boundary. The growth of mouse, rat, and human cells in culture was also inhibited by CVT-313 with the IC50 for growth arrest ranging from 1.25 to 20 microM. To evaluate the effects of CVT-313 in vivo, we tested this agent in a rat carotid artery model of restenosis. A brief intraluminal exposure of CVT-313 to a denuded rat carotid artery resulted in more than 80% inhibition of neointima formation. These observations suggest that CVT-313 is a promising candidate for evaluation in other disease models related to aberrant cell proliferation. 相似文献
129.
Since 1960 the cases of isolating the pseudopathogen agent have been recorded in Georgia at particular regular intervals. The accumulated material mainly involves epizootiological findings, which may provide a definite insight into the prevalence of this disease in Georgia. In 1960-1990, 31 strains were isolated in particular regions and populated areas; these included 17 strains from grey rats, 4 from house mice, 9 from common voles, and 1 from field mice. The particular constancy of isolation of the pseudotuberculosis pathogen from synanthropic rodents indicates that they may really infect humans, contrary to the opinion of G. P. Somov et al. who consider that among the synanthropic rodents there is only a chronic epizootic causing no animal death and that the role of the rodents in the spread of infection among humans is insignificant. However, doubt is cast on the validity of this proposition as the evidence for carriage alone among the rodents is lacking. The special literature contains no information on the dynamics of an epizootic process of pseudotuberculosis among the synanthropic rodents whereas the high pathogen detection rate in the viscera of these animals, recognized by Somov et al., mostly likely confirms the possibility of the course of epizootic manifested by the disease, but not only carriage. There is reason to consider pseudotuberculosis to be a naturally focal disease that is characterized by recurrent epizootics of varying intensity. Therefore, wild and synanthropic rodents may be as a reservoir and a source of infection. The circulation of the pathogen among wild and synanthropic rodents, in terms of their ability to be preserved and breed in the environmental objects, presents a permanent risk of not only sporadic cases, but also pseudotuberculosis outbreaks. 相似文献
130.
We conducted two feedlot trials and one metabolism trial to evaluate the effect of barley level, barley bulk density, and physical form of roughage on lamb growth performance and digesta kinetics. Level of whole barley (50, 70, 90%) and type of roughage (chopped or pelleted alfalfa) were evaluated in Trial 1 (50 d period). Trial 2 (50 d) evaluated barley bulk density (heavy = 671 and light = 607 kg/m3), form of roughage (pelleted or chopped alfalfa), and level of barley (80 or 40%). The influence of treatments used in Trial 2 on digesta kinetics was evaluated in Trial 3. Gain:feed increased and DMI decreased (P < .10) linearly with increasing level of barley, and ADG and DMI were greater (P < . 10) for lambs fed pelleted vs chopped alfalfa in Trial 1. The 70% barley diet produced the highest yield grade and kidney-pelvic fat and the lowest leg score among barley levels (P < .10). Lambs fed pelleted alfalfa had heavier carcasses and a thicker body wall than lambs fed chopped alfalfa (P < .02). In Trial 2, DMI was less and gain:feed greater (P < .01) for lambs fed the heavy barley than for lambs fed the light barley and for the 80% barley diet compared to the 40% barley diet. Lambs fed pelleted alfalfa had greater dressing percentages than lambs fed chopped alfalfa. Backfat and body wall thickness were greater (P < .10) for lambs fed the 80% barley diet than for those fed the 40% barley diet. In Trial 3, retention time of barley was greater (P < .10) for lambs fed light rather than heavy barley, and retention time of alfalfa was greater (P < .10) for lambs fed chopped compared with pelleted alfalfa. Acetate:propionate ratio was greater (P < .10) for lambs fed light vs heavy barley and lambs fed the 40 vs 80% barley diets. Ruminal pH was lower (P = .05) and in situ barley digestion greater (P = .03) over time in lambs fed the 80% barley diet than in lambs fed the 40% barley diet. Feedlot lamb ADG was not always greatest with high levels of barley; however, gain:feed improved at the higher barley levels. The higher barley levels seemed to result in fatter lambs. 相似文献