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Background: Postoperative nausea and vomiting (PONV) is a distressing problem after strabismus surgery. An inspired oxygen fraction has been reported to decrease PONV in patients after colon resection and to be more effective than ondansetron after gynecologic laparoscopy. Therefore, in a randomized, prospective, placebo-controlled study, the authors tested whether an inspired oxygen fraction of 0.8 decreases PONV in patients undergoing strabismus surgery and whether oxygen is more effective than ondansetron.

Methods: With approval of the authors' institutional review board, 210 patients were randomly assigned to receive one of three treatments: (1) 30% inspired oxygen in air plus intravenous administration of saline, (2) 80% inspired oxygen in air plus intravenous administration of saline, or (3) 30% inspired oxygen in air plus 75 [mu]g/kg ondansetron intravenously during induction. General anesthesia was standardized and included etomidate, alfentanil, and mivacurium for induction and sevoflurane for maintenance. PONV was evaluated 6 and 24 h postoperatively by an investigator unaware of treatment assignment.

Results: Overall postoperative incidence of nausea and vomiting was 41% for inspired oxygen fraction of 0.3 plus placebo, 38% for inspired oxygen fraction of 0.8 plus placebo, and 28% for inspired oxygen fraction of 0.3 plus ondansetron, respectively (P = 0.279). Therefore, there was no statistically significant difference of PONV incidence among groups.  相似文献   

3.
BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. “Safe” donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of “safe” donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of “safe” donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among “safe” donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors.  相似文献   
4.
This article reviews some of the tests for determining mental status in the infant and child. This assessment, in the setting of acute insult, is considerably more difficult than it is in the adult, since language skills and performance expectations differ in this age group.  相似文献   
5.
The empty sella syndrome is common in middle-aged women, usually presenting with headache, and only occasionally associated with endocrine or visual abnormalities. It is rare in childhood. Childhood cases tend to present either with endocrine disturbances, visual symptoms, or with craniofacial syndromes. We present three cases of complete empty sella with childhood onset, each discovered unexpectedly during evaluation of endocrine or visual dysfunction.  相似文献   
6.
The ability to identify surgical sinus disease using diagnostic nasal endoscopy and coronal CT scanning of the paranasal sinuses is studied prospectively. Fifty consecutive patients with symptoms of chronic sinusitis lacking surgical indications by traditional work-up comprise the patient population. Sixty percent had endoscopic or CT indications for surgery. There was a 90% correlation between endoscopy and CT examination with the combined work-up being more accurate than either modality alone. Functional endoscopic sinus surgery was performed in 18 cases. There were no major complications. Approximately 89% of the postoperative group report significant improvement, with 55.6% reporting total relief of symptoms. A complete endoscopic sinus work-up can often identify surgically correctable sinusitis despite normal routine rhinoscopic and plain-film examination. It is therefore, warranted in those patients with a suggestive history.  相似文献   
7.
As more mutations are identified in genes of known sequence, there is a crucial need in the areas of medical genetics and genome analysis for rapid, accurate and cost-effective methods of mutation detection. We have developed a multiplex allele-specific diagnostic assay (MASDA) for analysis of large numbers of samples (> 500) simultaneously for a large number of known mutations (> 100) in a single assay. MASDA utilizes oligonucleotide hybridization to interrogate DNA sequences. Multiplex DNA samples are immobilized on a solid support and a single hybridization is performed with a pool of allele-specific oligonucleotide (ASO) probes. Any probes complementary to specific mutations present in a given sample are in effect affinity purified from the pool by the target DNA. Sequence-specific band patterns (fingerprints), generated by chemical or enzymatic sequencing of the bound ASO(s), easily identify the specific mutation(s). Using this design, in a single diagnostic assay, we tested samples for 66 cystic fibrosis (CF) mutations, 14 beta-thalassemia mutations, two sickle cell anemia (SCA) mutations, three Tay-Sachs mutations, eight Gaucher mutations, four mutations in Canavan disease, four mutations in Fanconi anemia, and five mutations in BRCA1. Each mutation was correctly identified. Finally, in a blinded study of 106 of these mutations in > 500 patients, all mutations were properly identified. There were no false positives or false negatives. The MASDA assay is capable of detecting point mutations as well as small insertion or deletion mutations. This technology is amenable to automation and is suitable for immediate utilization for high-throughput genetic diagnostics in clinical and research laboratories.   相似文献   
8.
Self-incompatibility: how plants avoid illegitimate offspring   总被引:17,自引:1,他引:16       下载免费PDF全文
In some families of flowering plants, a single self-incompatibility (S) locus prevents the fertilization of flowers by pollen from the same plant. Self-incompatibility of this type involves the interaction of molecules produced by the S locus in pollen with those present in the female tissues (pistil). Until recently, the pistil products of the S locus were known in only two families, the Brassicaceae (which includes the cabbages and mustards) and Solanaceae (potatoes and tomatoes). A paper in this issue of the Proceedings describes the molecules associated with self-incompatibility in a third family, the Papaveraceae (poppies). We review current research on self-incompatibility in these three families and discuss the implications of the latest findings in poppy on the likely evolution of self-incompatibility in flowering plants. We also compare research into self-incompatibility with recent progress in understanding the mechanisms by which plants overcome infection by certain pathogens.  相似文献   
9.
Summary During x-ray-induced development of malignant lymphomas in mice their urinary excretion of eight modified nucleosides was monitored and the values were compared to the results of the histological examination of the animals at time of their sacrifice.It was found that the pathologically augmented excretion of modified nucleosides begins as much as several weeks before the malignant lymphomas can be diagnosed clinically. Thus some mice had increased levels of modified nucleosides even 10 weeks before sacrifice, though at the time of sacrifice the histological investigation reveled only some small foci of reticulum cell neoplasm in their spleen.It is therefore stressed that the usefulness of the determination of urinary modified nucleosides as an early noninvasive screening test for cancer in man and as an in vivo carcinogenicity test should be evaluated.Abbreviations pseudouridine - m1A 1-methyladenosine - m5C 5-methylcytidine - m1I 1-methylinosine - m1G 1-methylguanosine - m2G N 2-methylguanosine - m2G N 2,N2-dimethylguanosine - ac4C N 4-acetylcytidine - mt6A N-(9--d-ribofuranosylpurine-6-yl)N-methylcarbamoyl) threonine - acp3U 3-(3-amino-3-carboxypropyl) uridine - SD standard deviation  相似文献   
10.
Five children (three males, two females; four right-, one left-handed; age range 6 to 14 years) who developed aphasia after gross-total excision of left predominantly thalamic tumors are reported. Three patients had Broca aphasia, one had mixed transcortical aphasia, and one patient had conduction aphasia. In the months after surgery, three children improved while receiving radiation and/or chemotherapy, although none recovered completely. Two patients with malignant tumors developed worsening aphasia when the tumor recurred, and later died. Two of three patients tested had visuospatial difficulties in addition to language deficits. Attention and executive functioning were affected in three of three patients tested. Memory, verbal and/or visual functioning, were affected in four of four patients tested. Both patients who were tested showed transient right hemineglect. Two of two patients tested were probably apraxic. The wide range of deficits in these children highlights the importance of the thalamus and other subcortical structures in developing cognition.  相似文献   
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