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排序方式: 共有409条查询结果,搜索用时 31 毫秒
361.
362.
RC King PE Parrino JL Hurst KS Shockey CG Tribble IL Kron 《Canadian Metallurgical Quarterly》1998,66(4):1273-1276
BACKGROUND: Patients with large (> or = 5.0 cm) abdominal aortic aneurysms (AAA) frequently have marked associated coronary artery disease. We hypothesized that a single operation for coronary artery bypass grafting (CABG)/AAA would provide equivalent, if not improved, patient care while decreasing postoperative length of stay and hospital costs compared with staged procedures. METHODS: Eleven patients to date have undergone a combined procedure at our institution. Ten underwent CABG followed by AAA repair, whereas one patient received an aortic valve replacement before aneurysm repair. We performed a retrospective analysis comparing the postoperative length of stay and hospital costs for this single procedure to a combined cohort of 20 randomly selected patients who either received AAA repair (n = 10) or standard CABG (n = 10) during the same time period. RESULTS: No operative mortality has been reported. There were no episodes of neurologic deficit or cardiac complication after these procedures. The postoperative length of stay was significantly decreased for the CABG/AAA group compared with the combined postoperative length of stay for the AAA plus CABG group (7.44+/-0.88 days versus 14.10+/-2.00; p = 0.012). Total hospital costs were also significantly decreased for the CABG/AAA group compared with total hospital costs for the AAA plus CABG group ($22,941+/-$1,933 versus $34,076+/-$2,534; p = 0.003). CONCLUSIONS: A single operation for coronary revascularization and AAA repair is safe and effective. Simultaneous CABG and AAA repair substantially decreases postoperative length of stay and hospital costs while avoiding possible interim aneurysm rupture and repeat anesthesia. 相似文献
363.
Diagnosing acute myocardial infarction (AMI) in women is difficult since chest pain may not be a hallmark symptom. Research is needed to identify symptoms experienced by women with AMI to facilitate timely diagnosis. The purpose of this study was to identify new symptoms and their evolution experienced by women prior to diagnosis of AMI. Non-probability sampling was used to select 20 diverse women. Intensive home interviews were conducted and transcribed. Content analysis and constant comparison were used to develop nine data clusters: Location of Pain; Intensity of Pain/Sensations; Cardiovascular/Temperature Changes; Respiratory Sensations; Gastrointestinal Symptoms; Emotions; Hand and Arm Sensations; Neurological/Vision Changes; and Fatigue. Some women progressed to AMI in minutes while others had symptoms for weeks. Findings should increase awareness of women's symptoms of AMI. Further research is needed with a larger sample. 相似文献
364.
A new formula, expressing the local angular displacement of an orthodontic beam when subjected to a second-order couple applied at midspan, has been developed and analyzed. The computed displacements were compared with the results of ex vivo testing. There was good agreement between the results from the theoretical evaluation and the bench testing. Second-order activation of an orthodontic beam can be described in four sequential phases. The initial displacement is influenced by the second-order clearance between bracket-slot and wire as well as the relationship between the bracket-slot width and interbracket distance. During phase II there is a nonlinear relationship between applied couple and rotational displacement. Within phases three and four displacement is linearly related to the interbracket distance, provided the relationship between the bracket-slot width and interbracket distance remains constant. For a given tooth size, the second-order beam stiffness is exponentially related to bracket width. The experiments also show that even small deflections of thin stainless steel wires can lead to second-order couples of large magnitudes when using a clinically relevant interbracket distance. Consequently, it is important that the orthodontist evaluates his or her choice of bracket width and arch wire stiffness in each clinical case in order to avoid supra-physiologic force levels. 相似文献
365.
In our cross-sectional study we investigated the separate influence of three main factors, namely menopausal and estrogen status, and chronological age, on ten neurovegetative climacteric complaints reported in the scale of Kupperman et al. A multivariate statistical analysis was performed by a multivariate statistical approach on 1161 untreated women seen at the Menopause Center of the Ferrara University Hospital. Ninety women (age range, 41-54 years) were premenopausal; 492 women (age range, 38-55 years) were perimenopausal with irregular periods or amenorrhea for less than 12 months; 468 women (age range, 41-69 years) had a spontaneous menopause (age range, 37-66 years); 111 had had hysterectomy with bilateral ovariectomy while still regularly menstruating. Serum estrone was used as the indicator of the patients' estrogen status. A clear positive trend was demonstrated between menopausal status and the prevalence of depression, hot flushes, insomnia and joint pain. However, only the prevalence of hot flushes amongst these four symptoms was significantly related with the climacteric estrogen decline (beta = -0.006, P = 0.001). Moreover, menopausal status appeared to influence the intensity of fatigue, hot flushes, insomnia and paresthesia. Age was found to significantly (P = 0.053) co-vary only with the intensity of the hot flushes, with a positive relation (beta = 0.092, r = 0.104, P = 0.003), whereas estrone values did not significantly co-vary with any symptom. Furthermore, while neurovegetative symptoms are largely present also in the absence of hot flushes, when these latter are present, they exacerbate both the intensity and the prevalence of all the other symptoms.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
366.
S Dibart IL Chapple Z Skobe S Shusterman HL Nedleman 《Canadian Metallurgical Quarterly》1998,69(10):1172-1175
Generalized pre-pubertal periodontitis (GPP) is a rare entity that usually affects children with severe systemic diseases. We report the case of a 7-year-old male patient diagnosed with GPP, with no apparent systemic condition, who lost all his primary teeth to periodontal disease. Before extractions, while he was still in mixed dentition the subgingival plaque was collected and analyzed using DNA probes to 40 different microorganisms. Putative periodontopathogens such as Prevotella intermedia, Selenomonas noxia, Fusobacterium nucleatum, and Actinobacillus actinomycetemcomitans could be identified throughout the mouth. More intriguing was the colonization of the sulcus of some secondary teeth by potentially harmful microorganisms found in pockets of diseased adjacent primary teeth. 相似文献
367.
BS Hahn K Baek WS Kim CS Lee IL Chang YS Kim 《Canadian Metallurgical Quarterly》1998,36(12):1887-1893
The gene of capillary permeability-increasing enzyme-2 (CPI enzyme-2) was cloned from the cDNA library of Agkistrodon caliginosus and its nucleotide sequence was determined. Its sequence indicates that CPI enzyme-2 is synthesized as a pre-zymogen of 258 amino acid residues, including a putative secretory signal peptide of 18 amino acids and a proposed zymogen peptide of 6 amino acids. The amino terminal sequence deduced from the cDNA sequence was exactly consistent with that of CPI enzyme-2 except for the substitution of an amino acid (Gly27-->Ser). The open reading frame is very similar to those of plasminogen activator and thrombin-like proteases cloned from other snakes. The clone encoding CPI enzyme-2 belongs to the serine protease family. The active site of the enzyme is highly conserved at His41, Asp86 and Ser180. Its possible glycosylation sites, Asn-X-Thr/Ser, are located at amino acid residues 20-22, 55-57, 79-81 and 97-99. 相似文献
368.
RB Baudy LP Greenblatt IL Jirkovsky M Conklin RJ Russo DR Bramlett TA Emrey JT Simmonds DM Kowal RP Stein 《Canadian Metallurgical Quarterly》1993,36(3):331-342
A series of alpha-amino-3-(phosphonoalkyl)-2-quinoxalinepropanoic acids was synthesized and evaluated for NMDA receptor affinity using a [3H] CPP binding assay. Functional antagonism of the NMDA receptor complex was evaluated in vitro using a stimulated [3H]TCP binding assay and in vivo by employing an NMDA-induced seizure model. Some analogues also were evaluated in the [3H]-glycine binding assay. Several compounds of the AP-6 type show potent and selective NMDA antagonistic activity both in vitro and in vivo. In particular alpha-amino-7-chloro-3-(phosphonomethyl)-2-quinoxalinepropanoic acid (1) displayed an ED50 of 1.1 mg/kg ip in the NMDA lethality model. Noteworthy is alpha-amino-6,7-dichloro-3-(phosphonomethyl)-2-quinoxalinepropanoic++ + acid (3) with a unique dual activity, displaying in the NMDA receptor binding assay an IC50 of 3.4 nM and in the glycine binding assay an IC50 of 0.61 microM. 相似文献
369.
We have mapped the asparagine synthetase gene (ASNS) to 7q21.3 by fluorescence in situ hybridization. While this study refined the localization of the gene, it also revealed a rearrangement in a somatic cell hybrid line which was used in previous ASNS mapping. Using additional probes from other regions of human chromosome 7, we showed that this cell line (4AF/106/KO15) contained a rearranged chromosome 7 in which a segment of the long arm was apparently duplicated and inserted into the short arm. Caution should be used therefore when interpreting data obtained from this cell line for gene mapping studies. 相似文献
370.
BB Chan IL Kron TL Flanagan JA Kern CE Hobson CG Tribble 《Canadian Metallurgical Quarterly》1993,55(4):940-945
High-potassium cold storage solutions are currently used to preserve myocardial function during heart transplantation. However, the effects of high potassium concentration on vascular endothelial function are not well known. We therefore tested vascular rings for endothelial-dependent and endothelial-independent relaxation during storage in normokalemic, normothermic buffers and then in buffers supplemented with 10 to 110 mmol/L KCl. Maximal endothelial-dependent relaxation was significantly reduced at all high potassium concentrations. Endothelial-independent relaxation was impaired only with 80 and 110 mmol/L KCl buffers. Both endothelial-dependent relaxation and endothelial-independent relaxation returned to normal values after washout of excess potassium. Similarly, endothelial-dependent relaxation and endothelial-independent relaxation were assessed in rings after 24 hours of hypothermic storage in normokalemic Krebs buffer, and in buffers containing 20 and 110 mmol/L KCl. Maximal endothelial-dependent relaxation was significantly reduced after preservation in the high-potassium solutions, whereas endothelial-independent relaxation was not impaired. We conclude that there is significant impairment of endothelial function after cold storage in a high-potassium buffer. Inadequate washout of potassium during normothermic conditions may lead to further functional impairment of vascular responsiveness. A low-potassium storage medium is recommended for improved vascular protection. 相似文献