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91.

Purpose  

Worldwide, many displaced distal forearm fractures in children are treated by closed reduction under local anesthesia and cast immobilization. If mal-alignment of the fracture persists after initial reduction attempt, final fracture reduction will be performed under general anesthesia, followed by cast immobilization. The purpose of this study was to analyze the results of minimally invasive fixation with K-Wire or ESIN after fracture reduction in children under general anesthesia, compared with the results of closed reduction and plaster immobilization. We hypothesize that primary percutaneous fixation prevents secondary redisplacement and reduces the number of secondary interventions.  相似文献   
92.
Many chronic obstructive pulmonary disease (COPD) patients use their inhaler ineffectively and there is a trend towards increased inhaler resistance. We wanted to answer two questions: Is there a difference in preference and ease of use between Diskus (DK) and Handihaler (HH)? How acceptable are inhalation resistances? Sixty COPD patients, naive to DK and HH, but experienced in the use of other inhalers, had to read the instruction leaflet and demonstrate their inhalation technique. If errors were made, instruction was given and inhalation technique was checked again. Patients had to state a preference for DK or HH. Subsequently they inhaled through a range of resistances and scored the acceptability. There was no difference in the number of instructions needed for both inhalers. One third inhaled perfectly after reading the instruction leaflet, which increased to 85% after one instruction. More patients preferred the DK (43) than the HH (16). With decreasing resistance acceptability increases, but it reaches a plateau. Patients have a clear preference for the DK. There is no difference in the number of instructions needed to obtain a perfect inhalation technique, but for some patients one instruction is not enough. The trend to increase the resistance of inhalers has reached a critical point with regard to acceptability.  相似文献   
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It has been suggested that proliferation of enterobacteriaceae and/or anaerobes in the duodenum of some children with acute diarrhoea determines whether the episode becomes persistent. A review of published studies and the comparison of cultures of duodenal aspirates from Peruvian children with acute and persistent diarrhoea and diarrhoea-free children did not support this hypothesis. Although many children had enterobacteriaceae and/or anaerobes cultured there was no correlation with clinical and nutritional outcome. Age, nutritional status, the environment and the aetiology of the episode were determinants of the duodenal microflora independent of diarrhoea. Culture of the duodenal aspirates did not increase the yield of enteropathogens which were isolated more frequently from stools than from the duodenum. Despite the presence of a single strain or serotype of enterobacteriaceae suggesting that these bacteria were colonizing the duodenum, we were unable to demonstrate any adherence mechanisms in the majority of them. Two often bacteria with no other evidence of virulence caused diarrhoea in the RITARD rabbit model.  相似文献   
95.
PURPOSE: To determine prognostic factors, functional outcome and subjective rating after surgery for macular holes stage 2 and 3. METHODS: We studied 53 eyes of 49 patients undergoing vitreous surgery for macular holes stage 2 (46%) and 3 (54%). Mean follow-op was 114 weeks (32-204, std.dev. +/- 48), mean age 68.9 years (44-89, std.dev. +/- 6.8). 72% were female, 11% were pseudophakic, 19% phakic, 70% had a combined procedure (pars plana vitrectomy, phacoemulsification and IOL). Surgery consisted in a pars plana vitrectomy, peeling of epiretinal membranes and ILM, internal tamponade with SF6 (98%) resp. Si-oil in one case. Patients had to keep face-down position 6 x 20 minutes per day. RESULTS: The hole was completely closed in 90.6%. Anatomical failures included, 86% had an increase of VA, 41% = 5 lines (Final VA median 20/30, max. 20/20). No further increase of the retinal function occurred after 6 months. The visual result did not correlate with the duration of symptoms. 84% were satisfied with the outcome, subjective rating was not correlated with final VA or change of VA. 19% showed postoperative typical peripheral visual field defects. Visual field loss was not correlated with perioperative IOP elevation. CONCLUSION: Macular hole surgery has a high functional success rate. Postoperative visual field defects are an important problem.  相似文献   
96.
PURPOSE: Presentation and analysis of patients with vertical diplopia appearing after cataract surgery in retrobulbar anesthesia. SUBJECTS AND METHODS: Between 1990 and 1998 9 Patients with vertical diplopia following cataract surgery in retrobulbar anesthesia were studied in our Orthoptic Department. Each patient had complete orthoptic examination with Hess-screen-test. Additionally, some patients underwent neuroradiologic imaging and forced-duction testing. RESULTS: We subdivided the patients in a group of 4 patients with hypertropia and of 5 patients with hypotropia of the operated eye. All hypotropias were left-sided. Seven patients showed an overaction of the involved muscle without regression. Seven patients underwent surgery of a vertical muscle. Only 1 patient needed prismatic therapy postoperatively. The other 2 non-operated patients were satisfied with prisms alone. CONCLUSIONS: The proposed pathogenesis of vertical diplopia in these cases is fibrosis and contracture of the injured muscle, which could be due to anesthetic myotoxicity after direct injection into the muscle or to an intramuscular hemorrhage. On the other hand hypertropia could be a result of placement of bridle sutures. We discuss prevention and therapy of such complications.  相似文献   
97.
Mechanisms of action of arsenic trioxide   总被引:40,自引:0,他引:40  
Arsenic trioxide has shown substantial efficacy in treating both newly diagnosed and relapsed patients with acute promyelocytic leukemia (APL). As a single agent, it induces complete remissions, causing few adverse effects and only minimal myelosuppression. These successes have prompted investigations to elucidate the mechanisms of action underlying these clinical responses. Substantial data show that arsenic trioxide produces remissions in patients with APL at least in part through a mechanism that results in the degradation of the aberrant PML-retinoic acid receptor alpha fusion protein. Studies have also investigated concerns about the toxicity and potential carcinogenicity of long-term exposure to environmental arsenic. Arsenic apparently affects numerous intracellular signal transduction pathways and causes many alterations in cellular function. These actions of arsenic may result in the induction of apoptosis, the inhibition of growth and angiogenesis, and the promotion of differentiation. Such effects have been observed in cultured cell lines and animal models, as well as clinical studies. Because arsenic affects so many cellular and physiological pathways, a wide variety of malignancies, including both hematologic cancer and solid tumors derived from several tissue types, may be susceptible to therapy with arsenic trioxide. These multiple actions of arsenic trioxide also highlight the need for additional mechanistic studies to determine which actions mediate the diverse biological effects of this agent. This information will be critical to realizing the potential for synergy between arsenic trioxide and other chemotherapeutic agents, thus providing enhanced benefit in cancer therapy.  相似文献   
98.
Very-low-birthweight (VLBW) neonates are more prone to complications and death than term infants are. In a 15-year period, 19 neonates with VLBW were operated on for necrotizing enterocolitis (NEC). Indications for operation were pneumoperitoneum in 12 and deterioration of general condition in 7. Bowel resection and intestinal diversion was performed in 12, a lateral enterostomy at the site of perforation was created in 5, and 2 neonates with necrosis of the whole bowel underwent an exploratory laparotomy without any further surgical treatment. Surgical complications were found in one-third of the patients. The mortality rate was significantly higher when the ileum was affected. The survival rate was 68%. Prior to 1984 the survival rate was 37% (3/8); subsequently, it has improved to 91% (10/11) as a result of improved intensive therapy.  相似文献   
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