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71.
OBJECTIVE: To determine whether topical aqueous suppressant therapy applied after pars plana vitrectomy with gas tamponade prevents postoperative intraocular pressure (IOP) elevation. DESIGN: Prospective, nonrandomized comparative study. PARTICIPANTS: Forty-one patients who met inclusion criteria and underwent pars plana vitrectomy with gas tamponade (SF6 18%-20% or C3F8 12%-16%) over a 1-year period. INTERVENTION: Treatment eyes received topical aqueous suppressants at the end of surgery. MAIN OUTCOME MEASURES: Postoperative IOP at 4 to 6 hours, 1 day, and 1 week. RESULTS: Twenty-one control and 20 treatment eyes met the inclusion criteria. The IOP (in mmHg) measured at 4 to 6 hours (23.05 [control, 14.73 [treatment]) and 1 day (23.24 [control], 17.28 [treatment]) postoperatively showed a statistically significant difference between the groups (P = 0.0038) at 4 to 6 hours and a trend toward significance (P = 0.057) at 1 day. Eleven control and three treatment eyes had an IOP spike above 25 mmHg at 4 to 6 hours or 1 day postoperatively (P = 0.02), and six control eyes and one treatment eye had postoperative IOP greater than 30 mmHg. A pressure rise greater than 40 mmHg was seen in two control eyes and no treatment eyes. CONCLUSIONS: Use of topical aqueous suppressants after pars plana vitrectomy with long-acting gas tamponade is effective in preventing significant postoperative IOP elevation in most cases.  相似文献   
72.
Perceived barriers to medical-error reporting: an exploratory investigation   总被引:1,自引:0,他引:1  
Medical-error reporting is an essential component for patient safety enhancement. Unfortunately, medical errors are largely underreported across healthcare institutions. This problem can be attributed to different factors and barriers present at organizational and individual levels that ultimately prevent individuals from generating the report. This study explored the factors that affect medical-error reporting among physicians and nurses at a large academic medical center located in the midwest United States. A nominal group session was conducted to identify the most relevant factors that act as barriers for error reporting. These factors were then used to design a questionnaire that explored the likelihood of the factors to act as barriers and their likelihood to be modified. Using these two parameters, the results were analyzed and combined into a Factor Relevance Matrix. The matrix identifies the factors for which immediate actions should be undertaken to improve medical-error reporting (immediate action factors). It also identifies factors that require long-term strategies (long-term strategy factors) as well as factors that the organization should be aware of but that are of lower priority (awareness factors). The strategies outlined in this study may assist healthcare organizations in improving medical-error reporting, as part of the efforts toward patient-safety enhancement. Although factors affecting medical-error reporting may vary between different organizations, the process used in identifying the factors and the Factor Relevance Matrix developed in this study are easily adaptable to any organizational setting.  相似文献   
73.
In an effort to develop highly selective and potent agonists and/or antagonists for the hMC3 and hMC4 receptors, a new approach involving the use of linker arms and a backbone to side chain cyclization strategy was employed. Three key analogues were identified to have the required selectivity and potency at the hMC3 or hMC4 receptors, implicated to play pivotal roles in energy homeostasis and other biological effects. The novel cyclic peptide (O)C-CH(2)-CH(2)-C(O)-c-[His(6)-D-Phe(7)-Arg(8)-Trp(9)-Lys(10)]-NH(2) (1) was found to be a highly selective and potent agonist of the hMC4 receptor. Structure-activity studies have shown that replacing the succinyl linker arm of 1 by an o-phthalic acid group and substituting a D-Nal(2')(7) residue in place of D-Phe(7) results in a potent antagonist 7 at the hMC4 receptor. Furthermore, increasing the 23-membered lactam ring of 1 by one carbon atom (succinyl --> glutaric acid linker) gives a highly selective and potent antagonist 9 for the hMC3 receptor. Analogues 1, 7, and 9 therefore represent the first examples of a class of cyclic melanotropin ligands with high selectivity and defined biological activities at the physiologically important hMC3 and hMC4 receptors.  相似文献   
74.

Background  

Although clinical research is integral to the advancement of medical knowledge, physicians face a variety of obstacles to their participation as investigators in clinical trials. We examined factors that influence the participation of gastroenterologists and hepatologists in clinical research.  相似文献   
75.
This report describes the natural history of the Segond fracture and documents the radiographic appearance of the healed Segond fracture. The clinical and radiographic records of 129 patients with acute anterior cruciate ligament (ACL) injuries were reviewed. Four (3.1%) of these patients had Segond fractures. On follow-up radiographic examination, seven patients demonstrated a characteristic bone excrescence arising 3–6 mm inferior to the lateral tibial plateau. In four of the five patients for whom acute injury films were available this excrescence arose at the site of the earlier Segond fracture. Healing of such fractures is associated with a characteristic bone excrescence distinct from an osteophyte. This excrescence implies significant internal derangement of the knee.  相似文献   
76.
N-alkyl-N,N-dimethylamine-N-oxides (CnNO, n = 10-20 is the number of alkyl carbon atoms) stimulate the skeletal sarcoplasmic reticulum (SR) Ca(2+)-transporting ATPase activity at low concentrations and inhibit it at high concentrations. The minimum concentration (cmin), at which CnNO inhibits the ATPase, continuously decreases up to n = 16-18 and then increases. The values of Cmin are smaller than the CnNO critical micelle concentration (cmc) for C10NO-C14NO homologs, but larger than cmc for C18NO-C20NO homologs. The ATPase inhibition is caused by the CnNO-induced lipid bilayer structural perturbation in the ATPase annular region, modulated by the partition equilibria of the CnNO molecules between the bilayer and aqueous phase for short alkyl chain (n = 10-16) CnNO homologs, and between the bilayer, micelles and aqueous phase for long alkyl chain (n = 18-20) CnNO homologs.  相似文献   
77.
OBJECTIVE: We investigated the relationship between quality-adjusted life years (QALYs) and willingness to pay (WTP) in acute and chronic conditions. STUDY DESIGN AND SETTING: Face-to-face interviews were used to collect data in a convenience sample of women. Participants completed one interview evaluating preferences for an acute condition, post-chemotherapy nausea and vomiting (PCNV), and the other interview for a chronic condition (breast cancer). Preferences were elicited for QALYs using visual analogue scale (VAS), and standard gamble in addition to WTP. Because QALYs and WTP are purportedly based on the same underlying theoretical foundations, WTP was regressed onto change in QALYs, age, income, and health status. RESULTS: Regression analysis reported statistically significant models for all breast cancer (P < .001) and PCNV (P < .05) conditions tested. However, QALY was not a significant predictor of WTP. CONCLUSION: The results of this study indicate QALYs was a poor predictor of WTP for the conditions tested. Linear combinations of change in QALYs, age, income, and health status were a better predictor of WTP for chronic than acute conditions. This can be attributed to violations of underlying assumptions in measurement of QALYs with acute conditions and to problems with the use of WTP with chronic conditions.  相似文献   
78.
One of the primary criticismes of vestibular schwannoma (VS) radiosurgery is that the risk of surgical morbidity is increased for patients whose tumor progresses after the procedures. We reviewed the French experience of operated patients after failed Gamma Knife radiosurgery. From July 1992 to January 2002, 25 out of the 1000 treated patients underwent another treatment procedure for a gamma knife failure. Excluding the NF2 patients, 21 patients have been operated and the present study shows the data collected for 20 of them. In order to analyze the difficulties observed during the surgery, a questionnaire was filled by the surgeons. The mean interval between radiosurgery and removal was 36 Months, from 10 to 83 Months. The mean increase in Volume was 559% (37 to 3036%, median 160%). Evolution of the Koos grading was found from 8 grade II, 10 grade III et 2 grade IV to 10 grade III and 10 grade IV. Patients have been operated for radiological tumor growth in 7 cases and for clinico-radiological evolution in 13 cases. In 9 cases, the surgeon considered that he had to face unusual difficulties mainly because of adhesion of the tumor to neurovascular structures. Tumor removal was total in 14 cases, near total in 4 cases and subtotal in 2 cases. One case of venous infarction was noticed at the second day following surgery responsible of hemiparesis and aphasia that gradually recovered. At last follow-up examination, facial nerve was normal (House and Brackmann grade I and II) in 10 cases while it was a grade III in 7 cases and grade IV and V in 3 cases. We recommend that the decision for surgical removal of growing vestibular schwannoma after Gamma Knife treatment should be done after a sufficiently long follow-up period. Our results show that the quality of removal and of facial nerve preservation might be impaired by radiosurgery in half of cases. However these results do not support a change in our policy of radiosurgical treatment of small to medium size vestibular schwannoma.  相似文献   
79.
Nutritional anemia and its control   总被引:2,自引:0,他引:2  
Available studies on prevalence of nutritional anemia in India show that 65% infant and toddlers, 60% 1–6 years of age, 88% adolescent girls (3.3% had hemoglobin < 7.0 g/dl; severe anemia) and 85% pregnant women (9.9% having severe anemia) were anemic. The prevalence of anemia was marginally higher in lactating women as compared to pregnancy. The commonest is iron deficiency anemia. National programmes to control and prevent anemia have not been successful. Experiences from other countries in controlling moderately-severe anemia guide to adopt long-term measures i.e. fortification of food items like milk, cereal, sugar, salt with iron. Use of iron utensils in boiling milk, cooking vegetables etc may contribute significant amount of dietary iron. Nutrition education to improve dietary intakes in family for receiving needed macro/micro nutrients as protein, iron and vitamins like folic acid, B12, A and C etc. for hemoglobin synthesis is important. As an immediate measure medicinal iron is necessary to control anemia. Addition of folate with iron controls anemia and is neuroprotective. Evidence in early childhood suggests vitamin B12 deficiency anemia; thus it may also be given alongwith iron and folate.  相似文献   
80.
Kalavagunta S  Roy D  Fish B  Jackson S 《Rhinology》2002,40(4):223-225
Medial maxillectomy via lateral rhinotomy approach is used in the treatment for tumours affecting the lateral nasal wall. The most frequent complications are crusting, epicanthal scarring and epiphora. The authors report a rare case of blindness secondary to indirect optic neuropathy following medial maxillectomy undertaken to treat a malignant melanoma arising in the lateral nasal wall. It is important to keep in mind, the possibility of this rare complication, while patients are being counselled preoperatively for medial maxillectomy.  相似文献   
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