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91.
ObjectivesThe aim of the present study is to evaluate the feasibility and safety of performing PNL under local anesthesia in a selected group of patients who are at high risk for general anesthesia.Patients and methodsForty seven patients underwent PNL under local anesthesia. There were 38 males and 9 females with a mean age of 62 years. All patients were at medical high-risk for general anesthesia, with an American Society of Anesthesiologists (ASA) score of 3. The indications for local anesthesia in this study were obstructed single functioning kidney with azotemia in 29 patients, hepatic insufficiency in 8 patients, cardiac problems in 7 patients and 3 patients had hepatocellular carcinoma. The mean stone size was 2.7 cm (range 2–3.1 cm). Local infiltration with 10–20 cc of 2% lidocaine at the site of puncture was used in all cases. Narcotics were given 30 min prior to the procedure and medazolam was given intraoperatively upon demand. Utrasound guided puncture was performed in all cases and tract dilatation was then done under fluoroscopy using high pressure balloon catheter in 35 and Alken's metal dilators in 12 cases. Stones were then retrieved after disintegration in the same cession in 33 patients, while the other 14 patients underwent staged PNL, where a 12 Fr. nephrostomy tube was placed in the first stage, followed by tract dilatation and stone retrieval one week later.ResultsOut of 47 patients included, 44 had successful PNL either one stage (30 patients) or two stages (14 patients). Only 3 patients could not tolerate pain and the procedure was terminated after placement of nephrostomy tube and stone retrieval was completed later under general anesthesia.ConclusionOur results demonstrated that PNL under local anesthesia with narcotics and sedatives seems to be a satisfying solution for the treatment of a selected group of patients with renal pelvic stones and who have high anesthetic risk. However, additional studies with different groups of patients are required to validate our results.  相似文献   
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94.
A prospective study of blood donations in healthy elderly persons   总被引:1,自引:0,他引:1  
Iron stores were observed in 57 healthy elderly volunteers, between 63 and 77 years of age, who donated 5 units of blood over approximately 1 year. An equal number of nondonors who contributed approximately 7 mL of blood at each visit for iron status measurements only were seen at the same frequency as the donor population. At entrance to the study, iron stores in women and men averaged 724 and 875 mg, respectively. After five donations, mean iron stores dropped to 67 mg in women (n = 27) and 362 mg in men (n = 30); four women (15%) became iron deficient, while two (7%) developed iron deficiency anemia. Three men (10%) developed iron deficiency, but none were found to be anemic. Mean intakes of iron were 23.3 and 22.5 mg per day, respectively, for women and men. Iron intakes were adequate to meet iron requirements of nondonors, but they were not sufficient to halt the steady decrease in iron stores among the donor population, in whom iron absorption increased from approximately 5 percent at entrance to 14 percent at the time of the fifth donation. In summary, healthy elderly persons may contribute to the national blood resource; however, donations should probably be limited to less than five per year or donors should regularly take an iron supplement to preserve reasonable amounts of iron reserves.  相似文献   
95.
We compared the efficiency of removing cosmetic eyeliner deposits from soft contact lenses with a variety of surfactant cleaners. Four types of daily cleaners were used to clean two groups of soft contact lenses (Group 1 and Group 2 : FDA classification) contaminated with an eyeliner. The lenses were cleaned in a Clensatron 700CL Automatic Contact Lens Cleaning unit. The amount of lens contamination before and after cleaning was quantified by digitising a photograph of the lens surface. We found that: 1. the eyeliner was less likely to adhere to Group 2 lenses, 2. the efficiency of removing eyeliner was independent of the cleaning solutions we used; when contaminated, Group 2 lenses were generally easier to clean, 3. the Clensatron unit was not as efficient as digital rubbing in removing the eyeliner.  相似文献   
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Summary. The Pasteur effect and the associated acidosis have long been considered a major cause of platelet death during storage. We have investigated this phenomenon using a defined platelet preparation and a system whereby the oxidative and glycolytic contributions to total ATP production can be measured over a range of oxygen concentrations from saturating (pO2=158mmHg) to anoxic (pO2=OmmHg). Platelets do not show a Pasteur effect until the pO2 decreases to & 2'OmmHg, whereupon lactate production increases 1-5-fold. The Pasteur effect is therefore not a likely cause of platelet death during storage where pO2 in a storage bag typically drops to no less than 50mmHg. The data also have implications for the role of oxygen diffusion in oxidative metabolism, and for the compensatory nature of the Pasteur effect. As platelets are relatively small cells, and the onset of the Pasteur effect occurs at a relatively low oxygen concentration, diffusion may limit the rate of oxygen consumption in most other (larger) cells. The Pasteur effect is only fully compensative if the P/O2 ratio used for the calculations is lower than the conventional one. Since recent research strongly suggests that the conventional P/O2 ratio is too high, examples of fully compensative Pasteur effects may be more common than the literature suggests.  相似文献   
98.
The radiological findings of ultrasound, CT and MR of a case of bilateral subacromial bursitis with macroscopic rice bodies is described. The previous literature is also reviewed.  相似文献   
99.
This study was performed to determine whether peritoneal T cells are suppressed in the CD4+ or CD8+ T cell subpopulation and whether they are Th1 or Th2 predominant in women with endometriosis. Immune cells in the peritoneal fluid (PF) were obtained from women undergoing laparoscopy for endometriosis or tubal ligation. Three-colour flow cytometry was utilized for immunophenotyping of peritoneal fluid mononuclear cells (PFMC). Concentrations of interleukin (IL)-4, IL-5 and interferon-gamma (IFN-gamma) produced by PFMC with and without mitogen stimulation and concentrations of IL-10 and IL-12 were measured in PF. The peritoneal T lymphocytes were predominantly of the Th1 type that produced much more IFN-gamma but less IL-4 or IL-5 in women with or without endometriosis. The decrease in peritoneal lymphocytes was significant in the HLA-DR+ CD4+ CD3+ subpopulation and the concentrations of peritoneal IL-10 and IL-12 were significantly elevated in women with early stage endometriosis. There was impaired IL- 5 production by PFMC after phytohaemagglutinin stimulation in women with advanced stage endometriosis. We concluded that the activated peritoneal CD4+ Th1 cells from the women with endometriosis were decreased in number. The suppression of these T cells may be due to the elevation of IL-10 and IL-12 in the peritoneal fluid.   相似文献   
100.
Aim: Reduced basal cortisol is reported in allergic disease. We investigated if basal salivary cortisol levels were reduced in children with asthma or allergic rhinitis, controlling for inhaled corticosteroids (ICS) use. Methods: Morning and evening saliva of asthmatic children aged 7–12 years (n = 50) and that of controls (n = 52) were sampled. A total of 19 asthmatics and four controls had allergic rhinitis. Healthy children were controls without rhinitis. Of all, 14 asthmatic children used low, and 12 used moderate or high doses of ICS. Cortisol was analysed by radioimmunoassay. Results: Morning salivary cortisol median (95% CI) was lower in asthmatics (8.7 (7.1, 9.7)) compared with that in controls (10.4 (9.6, 11.8); p = 0.006), which was similar for evening cortisol levels. Regression analyses demonstrated that asthmatics using moderate or high doses of ICS had reduced morning salivary cortisol adjusted (for age and gender) odds ratio (aOR) (95% CI) (0.54 (0.37, 0.80); p = 0.002) and reduced evening cortisol aOR (0.09 (0.01, 0.6); p = 0.02) compared with that in healthy children. Asthmatics with rhinitis on no or low doses of ICS had reduced morning cortisol aOR (0.73 (0.56, 0.96); p = 0.02) compared with that in healthy children. Conclusion: Asthmatic children on moderate or high doses of inhaled corticosteroids had reduced salivary cortisol, but co‐morbidity of asthma and rhinitis was also associated with reduced cortisol levels.  相似文献   
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