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101.
102.
Kalish RB McCullough L Gupta M Thaler HT Chervenak FA 《Obstetrics and gynecology》2004,103(6):1137-1141
OBJECTIVE: The purpose of the study was to investigate the incidence of intrapartum patient choice cesarean delivery-patients' requesting cesarean delivery and physicians' offering it during labor-and factors possibly influencing these requests and offers. METHODS: For a 6-month period from May 1, 2002, to October 31, 2002, obstetricians were asked to complete a questionnaire after all intrapartum cesarean deliveries regarding whether cesarean delivery was offered by the obstetrician or requested by the patient before being medically indicated. Patient medical records and physician demographic information were reviewed. RESULTS: There were 422 cases that met inclusion criteria. Questionnaires were completed in 100% of cases. Cesarean delivery was offered in 13% before a clear medical indication and requested in 8.8%. Older obstetricians, maternal-fetal medicine specialists, and full-time faculty were significantly more likely to offer cesarean delivery (P =.009, P <.001, and P =.015, respectively). Patients who were unmarried or undergoing labor induction were less likely to request cesarean delivery (P =.029 and P =.035, respectively). Maternal age, parity, stage or length of labor, epidural use, gestational age, insurance status, day of week, and time of delivery did not affect whether patients requested or were offered cesarean delivery. CONCLUSION: This study documents a heretofore unrecognized clinical entity: intrapartum elective cesarean delivery. Physician characteristics, as opposed to patient characteristics or intrapartum factors, are a major determinant of whether laboring patients are being offered cesarean delivery. LEVEL OF EVIDENCE: III 相似文献
103.
Deusch E Thaler U Kozek-Langenecker SA 《Anesthesia and analgesia》2004,99(3):665-8, table of contents
Physicochemical characteristics of hydroxyethyl starch (HES) molecules determine their side effects on hemostasis. Our aim in the present experiments was to test the antiplatelet effect of novel high molecular weight HES. Citrated whole blood was hemodiluted in vitro (0% and 20%) with either HES 550 (Hextend), HES 600 (6%Hetastarch-Baxter), HES 200 (Eloh?st), or the solvent of Hextend in its commercially available solution. The availability of glycoprotein IIb-IIIa was assessed on nonstimulated and on agonist-induced platelets using flow cytometry. Glycoprotein IIb-IIIa availability increased significantly after hemodilution with Hextend and its solvent by 23% and 24%, respectively, but decreased in the presence of 6% Hetastarch-Baxter and Eloh?st by 18% and 15%, respectively, with no significant difference between the latter two colloids. This study shows that Hextend does not inhibit platelet function as anticipated by its high molecular weight and degree of substitution. The unexpected platelet stimulating effect of Hextend is unique among the currently available HES preparations and may, at least in part, be induced by its solvent containing calcium chloride dihydrate (2.5 mmol/L). The platelet-inhibiting effect of 6%Hetastarch-Baxter was not significantly different from that of medium molecular weight HES 200. 相似文献
104.
Thaler K Weiss EG Nogueras JJ Arnaud JP Wexner SD Bergamaschi R 《Acta chirurgica Iugoslavica》2004,51(2):45-47
The aim of the study was to compare the impact of surgical access to sigmoid resection on recurrence rates in patients with uncomplicated diverticulitis of the sigmoid (UDS) at a minimum follow-up of five years. Recurrence after surgery was defined as left lower quadrant pain, fever and leucocytosis with consistent CT and enema findings on admission and at 6 weeks, respectively. Outcome measures included splenic flexure mobilization, specimen length, inflammation at proximal resection margin and presence of teniae coli at distal resection margin. Seventy-nine patients undergoing laparoscopic sigmoid resection (LSR) were compared with 79 matched controls with open sigmoid resection (OSR) operated on at two institutions during the same period. Patients were well matched for age, gender, body mass index, ASA grading and symptoms duration, but not for follow-up length (81.9 vs. 86.9 months, p = 0.046). The rate of splenic flexure mobilization (19 vs. 41, p 0.001), specimen length (16.1 vs. 18.3 cm, p = 0.048), presence of inflammation at proximal resection margin (21 vs. 4, p 0.001), and presence of teniae coli at distal resection margin (4 vs. 53, p 0.001). Three LSR patients and 7 OSR patients had one recurrence (p = 0.19). There were no significant differences in rates of flexure mobilization, specimen length, and rates of inflammation present at proximal resection margin in 10 recurring and 145 non-recurring patients. The rate of teniae coli present at distal resection margin was significantly increased in recurring patients (7 vs. 43, p = 0.03). Surgical access to sigmoid resection for UDS is unlikely to have an impact on recurrence rates provided that the oral bowel end is anastomosed to the proximal rectum rather than to the distal sigmoid. 相似文献
105.
Stifter E Sacu S Weghaupt H König F Richter-Müksch S Thaler A Velikay-Parel M Radner W 《Journal of cataract and refractive surgery》2004,30(6):1259-1267
PURPOSE: To investigate the influence of various types of cataract on reading performance in a standardized reading test setting. SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria. METHODS: The reading performance of 94 eyes with age-related cataract and normal macular function was evaluated with the Radner Reading Charts preoperatively and 4 weeks after cataract surgery. Distance visual acuity was tested with the ETDRS charts. Cataracts were graded using the Lens Opacities Classification System (LOCS) III, on which NO is nuclear opalescence and NC is nuclear color. RESULTS: Patients with pure nuclear cataracts (LOCS III: NO/NC 2.1-5) achieved a normally high MRS (99.84% +/- 7.65% of their postoperative MRS): preoperative MRS(1): 190.6 +/- 30.74 words per minute (wpm); postoperative MRS(2): 191.21 +/- 29.36 wpm. Patients with mixed nuclear-cortical cataracts (LOCS III: NO/NC 2.1-5; C>2) preoperatively achieved 96.96% +/- 5.6% of their postoperative MRS (MRS(1): 175.77 +/- 31.54 wpm; MRS(2): 181.34 +/- 30.56 wpm). In dense nuclear cataracts (LOCS III: NO/NC>5), the MRS was significantly reduced, achieving only 72.64 +/- 19.19% of the postoperative MRS (MRS(1): 133.06 +/- 39.43 wpm; MRS(2): 185.76 +/- 40.18 wpm). In posterior subcapsular cataracts, the preoperative MRS (134.1 +/- 33.72 wpm) was significantly lower than postoperatively (191.14 +/- 27.08 wpm). CONCLUSIONS: In contrast to dense nuclear cataracts and posterior subcapsular cataracts, the preoperative reading speed of patients with pure nuclear or nuclear-cortical cataracts was normal at large print sizes. The preoperative evaluation of reading acuity and speed with standardized reading tests can therefore be used to estimate the postoperative reading performance in the latter 2 types of cataract. 相似文献
106.
Thaler ER 《The Laryngoscope》2002,112(9):1533-1542
OBJECTIVE/HYPOTHESIS: The thesis explores the applicability of electronic nose technology in medical decision-making. Specifically, the studies undertaken in the thesis were designed to test the ability of the electronic nose to assist in diagnostic questions encountered in the field of rhinology. STUDY DESIGN: Three separate studies were undertaken. All involved analysis of specimens by the electronic nose, obtained either in vitro or in vivo: known matched sets of cerebrospinal fluid and serum, bacterial samples from known plated specimens, and culture swabs taken from patients suspected of having rhinosinusitis who also had a matched standard bacterial culture taken from the same site. The goal of analysis was to determine whether the electronic nose was able to identify or categorize specimens or groups of specimens. METHODS: Each specimen was tested using the organic semiconductor-based Cyranose 320 electronic nose. Data from the 32-element sensor array were subjected to principal-component analysis to depict differences in odorant patterns. Distinction of specimens was identified by calculation of Mahalanobis distance. RESULTS: The electronic nose was able to distinguish serum from cerebrospinal fluid in pure isolates as well as in isolates collected on small cottonoid pledgets at amounts of 0.2 mL or greater. It was also able to distinguish between control swabs and bacterial samples as well as among bacterial samples collected in vitro. Preliminary work suggests that it may be able to distinguish between presence and absence of bacterial infection in specimens collected on nasal swabs. CONCLUSIONS: The electronic nose is able to distinguish reliably between cerebrospinal fluid and serum sampled in small amounts, may be able to identify presence and type of bacterial pathogen in vitro, and is able to identify presence or absence of bacteria on nasal swabs. Because this information is available immediately, the electronic nose may be a powerful new technology for diagnostic use, not only for rhinologic purposes but in many other aspects of medicine as well. 相似文献
107.
108.
Nitric oxide in oocyte maturation,ovulation, fertilization,cleavage and implantation: a little dab'll do ya 总被引:3,自引:0,他引:3
Nitric oxide synthases, the enzymes that generate NO gas, may be involved in reproduction and development of multicellular organisms at many levels and thus provide important targets for design of drugs to intervene in reproductive processes. This review focuses on the role of nitric oxide in key events of reproduction including gamete activation, fertilization, early cell divisions and implantation. A general trend highlighted by the studies reviewed is that NO plays a biphasic role in reproduction. That is, a narrow range of NO concentrations, usually low, will stimulate or enhance these early events in reproduction, but either a lack of NO or too much NO has negative consequences. One of the shortcomings of the field currently is the lack of molecular detail concerning the mechanism of NO action. This has been due in part to lack of technology for effective detection of NO and its molecular targets. A few targets of NO have been indirectly implicated and advances in this area of research will provide substrates for development of drugs to control reproductive function. Work from both invertebrate and vertebrate model systems is presented and implications for control of reproductive physiology discussed. Ubiquity of NO signaling in animals may mean that effective control of reproduction must target mediators of NO action and not NOS enzymes themselves. 相似文献
109.
McCullough JA Evoy D Sweeney KJ Meyers C Ravi N Keeling N Byrne PJ Reynolds JV 《Irish journal of medical science》2003,172(3):132-135
Background Gastric carcinoma is a significant cause of death in Ireland. Surgery offers the best option of cure, but the five-year survival
following resection remains dismal at 10–15%. Experience from Japan and from some Western units suggest that an extended (D2)
lymphadenectomy in association with gastrectomy increases the prospect of cure, but concern about the morbidity and mortality
of this operation and lack of evidence from randomised studies has limited its acceptance.
Aims This study reports the experience of a specialist upper gastrointestinal unit with D2 gastrectomy in a four-year audit.
Methods Sixty-two resections were performed for gastric cancer. Results Nineteen patients were deemed unsuitable for the D2 procedure
and underwent a more limited lymphadenectomy (DO or D1). Forty-three patients underwent D2 resection, 12 with an oesophagogastrectomy,
22 with total gastrectomy and nine with a sub-total distal resection. Eight patients undergoing D2 resection had extended
resections, five with splenectomy and three with a distal pancreatectomy. Post-operative complications occurred in 31% of
patients. Thirty-day and 90-day mortality were zero. Median survival was 822 days in the D2 group (range 120–1,320).
Conclusions These results show that a D2 gastrectomy can be performed with a low morbidity and mortality and a median survival of greater
than two years. 相似文献
110.
OBJECTIVES/HYPOTHESIS: Endoscopic staple-assisted esophagodiverticulostomy (ESED) is a newly described method of surgically correcting Zenker's diverticulum. Initial reports on the ease and success of the surgery have been quite enthusiastic, making it seem the procedure of choice. We initiated the procedure in an algorithm of treatment of Zenker's diverticulum, to further explore the feasibility and outcome of this new technique. STUDY DESIGN: This is a case series of 23 patients with Zenker's diverticulum who have undergone surgical repair. For each patient, an attempt at ESED was made. If unsuccessful, an open approach was then taken. RESULTS: Seven of 23 patients (30%) were unable to be treated with ESED because of inability to expose the diverticulum or unfavorable anatomy of the diverticulum itself. Of the remaining 16 patients, ESED was successful in resolving the symptoms of diverticulum in 14 (87%). Two patients (13%) were somewhat improved but had persistent dysphagia. No significant complications occurred. All patients resumed oral diet within the first 24 hours after surgery. CONCLUSION: Esophagodiverticulostomy is an excellent method of surgically correcting Zenker's diverticulum in many patients, but anatomical considerations may prevent its use, making open approaches of continued importance in a surgeon's armamentarium. 相似文献