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71.
OBJECTIVE: Our purpose was to compare the relative risk of vessel injury after use of a 5 mm conical-tipped trocar, a 5 mm pyramidal-tipped trocar, and a 10 mm pyramidal-tipped trocar in a rabbit vessel model.STUDY DESIGN: Plastic templates were placed in front of and behind 108 mesenteric vessels in 11 anesthetized New Zealand White rabbits. Laparoscopic trocars were inserted through the templates and mesentery. The incidence of vessel injury was determined at distances from the vessels ranging from 0 to 5 mm.RESULTS: The 5 mm conical trocar resulted in a vessel injury rate of 88% at 0 mm from the vessel but 0% at 1 or 2 mm. The 5 mm pyramidal trocar resulted in 100%, 88%, and 62% injury rates of 0, 1, and 2 mm from the vessels, respectively. The 10 mm pyramidal trocar resulted in a 100% injury rate at 0, 1, 2, or 3 mm from the vessels and 80% and 40% at 4 mm and 5mm, respectively.CONCLUSION: The relative risk of vessel injury is significantly increased by the use of pyramidal-tipped trocars when compared with conical-tipped trocars, especially if larger diameter trocars are used.  相似文献   
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The computerized database system described was initially developed in 1986 to facilitate analysis of retrospective head and neck cancer data from the Royal Adelaide Hospital Department of Otolaryngology. This has now been expanded to become an on-going patient information management system. It is based on the dBase-III-Plus database package and is implemented on an IBM XT compatible computer. The system was designed to be used by staff without specialist computer skills and is therefore largely “menu-driven.” The main functions include patient record creation, update, and retrieval, and the production of reports including graphical presentations. There is also a powerful but easy to use query facility. The system has already provided much useful epidemiological material but is now beginning to fulfill an even more important role in patient follow-up and in assisting evaluation of alternative treatment protocols.  相似文献   
76.
This study was designed to assess the accuracy of end-tidalPco 2 and transcutaneousPco 2 as measurements of arterialPco 2 in extubated, spontaneously breathing patients recovering from general anesthesia. In 30 patients, measurement of arterial transcutaneous, and end-tidalPco 2 were taken simultaneously with body temperature approximately every 15 minutes over a 2-hour period. ArterialPco 2 values were corrected for body temperature. Values for Paco 2 were compared with those forPetCO2 and Psco 2 by linear regression analysis and by calculation of bias ± precision. Thirty-six percent of the capnogram tracings obtained did not develop a plateau phase. We found poor correlation between end-tidal and arterialPco 2 regardless of the shape of the capnogram tracing, as well as poor correlation between transcutaneous and arterialPco 2. Although the measurements of bias and precision of noninvasivePco 2 monitors in this population are comparable to studies in other populations, we advise caution in relying on the routine use ofPetCO2 or Psco 2 for the noninvasive assessment of respiratory depression in extubated, spontaneously breathing patients recovering from general anesthesia.  相似文献   
77.
Monocytes purified with cell scatter monitored counterflow centrifugation were cultured in plastic (adherent) and in teflon culture bags (suspension). Sequential changes were monitored during 15 days by measuring intracellular activity of three enzymes of intermediary metabolism: glucose-6-phosphate dehydrogenase (G-6-PDH), phosphohexose isomerase (PHI) and isocitrate dehydrogenase (ICDH), and the two acid hydrolases: acid phosphatase (ACP) and N-acetyl-beta-glucosaminidase (NAG). In teflon grown macrophages a significantly lower G-6-PDH activity was seen after 15 days in comparison to plastic adherent macrophages (P less than 0.0002). For the other enzymes similar values for both culture modalities were found. The significantly, cycloheximide insensitive, higher values for G-6-PDH, PHI and ICDH in 2 h plastic adherent monocytes in comparison with plastic non-adherent monocytes, suggest a relationship between adherent capacity and the level of intermediary metabolism. The overall yield of plastic adherent macrophages after 15 days was 35% in contrast with 89% for the in suspension cultured macrophages. This corroborates the existence of adherent and non-adherent monocytes, both capable of differentiation in vitro. In 14 patients with advanced Hodgkin's disease (HD) and 14 normal controls, monocyte differentiation was studied applying both culture modalities. The enzyme levels, reflecting growth and intermediary metabolism, were similar for both groups. The adherent capacity and yield, both in teflon and in plastic, after 15 days was comparable for both groups. It was concluded that in vitro monocyte differentiation in the presence of autologous serum was qualitatively and quantitatively normal in advanced HD; this is in favour of an intrinsically normal function of monocytes in HD.  相似文献   
78.
N-I Max Kjellman  MD  PhD    Michael T Stevens  BSc  CStat   《Allergy》1995,50(S21):14-22
A programme of clinical studies was carried out to determine the basic efficacy and safety of 2% nedocromil sodium eye drops (Tilavist) in treating allergic conjunctivitis, in 2,905 patients from 3–76 years of age. Results of all the double-masked placebo comparative studies completed to date - five in vernal keratoconjunctivitis (VKC), five in perennial (PAC) and 16 in seasonal allergic conjunctivitis (SAC) - have been assessed in a statistical overview analysis. Nedocromil sodium, administered four times daily to 153 patients with VKC, was significantly more effective than placebo (155 patients) and in the clinicians' opinion gave good control in 76% of cases, compared with 46% for placebo (p < 0.001). Patients with chronic symptoms of PAC also responded better to nedocromil sodium given four times daily (n = 146) rather than twice daily (n = 86), and significantly more patients (p < 0.001) were effectively controlled by four times daily treatment with nedocromil sodium (72%) than with placebo (47%; n= 156). Twice-daily dosage with nedocromil sodium (n = 677) was adequate for SAC, however, and the treatment was statistically better than placebo (p < 0.01-p < 0.001) whether dosed twice or four times daily. Speed of action was assessed in seven SAC studies in which 79% of all patients (n = 295) using nedocromil sodium had experienced relief of symptoms when questioned, half of them within 15 minutes and 74% during the first hour after dosing. Test treatments were well-accepted by both adults and children, and there were no major adverse events. Minor irritations reported more frequently with nedocromil sodium than placebo were stinging or burning of the eyes on application of the drops and a distinctive taste, noted by 5% of the active treatment group (n = 1,552).  相似文献   
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This work describes our experience in reviewing the performance criteria for display systems and how we have implemented a practical approach to the assessment of the workstation environment in a large tertiary care hospital. The acceptance criteria contained in the draft report of Topic Group 18 of the American Association of Physicists in Medicine (AAPM) were used as a basis for assessment of primary and secondary displays. A telescopic photometer was used to measure the maximum luminance and the contrast ratio of the image for the displays used in our radiology department and in the operating and emergency rooms using the standard Society of Motion Picture and Television Engineers (SMPTE) pattern, in ambient light and with light decreased as much as possible. About half of the displays met the AAPM criteria for minimum luminance and contrast ratio in low light. None of the systems met the contrast ratio criteria in ambient light. The challenges in improving the performance and calibrating displays are discussed.  相似文献   
80.
As a philosophical position, pragmatism can be critiqued to distinguish truth only with methods that bring about desired results, predominantly with scientific enquiry. The article hopes to dismiss this oversimplification and propose that within mental health nursing, enquiry enlightened by pragmatism can be anchored to methods helping to tackle genuine human problems. Whilst pragmatists suggest one reality exists, fluctuating experiences and shifting beliefs about the world can inhabit within; hence, pragmatists propose reality has the potential to change. Moreover, pragmatism includes being cognisant of what works to whom reality concerns, making reality context-driven, with a view to understand how actions shape experiences so what is generated has usefulness. Hence, it somewhat follows pragmatism can inform mental health nursing, after all, nursing is a discipline of action, and awareness is needed in how actions produce experiences that patients find helpful. Given the principles of recovery are preferably adopted in mental health care, the paper will explore how pragmatism can help nurses move towards that goal; specifically, with patients voicing their experiences. This is because like pragmatism, recovery subscribes to hope that reality can progress, and through meaningful experiences and beliefs, patients have expertise about personal difficulties alongside how life may flourish, despite mental illness.  相似文献   
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