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41.
B L Y Cheuk A C W Ting S W K Cheng 《European journal of vascular and endovascular surgery》2005,29(2):150-155
OBJECTIVE: Serological studies have suggested that one of the risk factors for aneurysm development is C. pneumoniae infection. The purpose of this study was to evaluate whether there is an association between the presence of C. pneumoniae DNA in aneurysms and ruptured abdominal aortic aneurysms. METHODS: Aortic walls were collected consecutively from 30 patients with intact AAA, 16 patients with ruptured AAA and 19 healthy organ donors (control). Purified DNAs from all aortas were analyzed for the presence of C. pneumoniae DNA in parallel by polymerase chain reaction-enzyme immunoassay (PCR-EIA) and agarose gel electrophoresis. PCR-EIA has a high sensitivity in detecting low DNA copy number in clinical atherosclerotic samples. RESULTS: C. pneumoniae DNA was detected more frequently in patients with aneurysms, particular with ruptured aneurysms. The incidence of positive C. pneumoniae DNA was 73.3% in intact AAA and 10.5% in control aortas, with the highest frequency in ruptured AAA (100%) (p < 0.05). CONCLUSION: Giving the high specificity and sensitivity of PCR-EIA, these findings support the association of C. pneumoniae in the pathogenesis of aneurysm development, growth and rupture. 相似文献
42.
Cefazolin plus ceftazidime versus imipenem/cilastatin monotherapy for treatment of CAPD peritonitis--a randomized controlled trial. 总被引:2,自引:0,他引:2
Chi-Bon Leung Cheuk-Chun Szeto Kai-Ming Chow Bonnie Ching-Ha Kwan Angela Yee-Moon Wang Siu-Fai Lui Philip Kam-Tao Li 《Peritoneal dialysis international》2004,24(5):440-446
BACKGROUND: Peritonitis is a serious complication of peritoneal dialysis (PD). We studied the efficacy of imipenem/cilastatin monotherapy in the treatment of PD-related peritonitis. METHODS: We performed an open-label, randomized control study comparing imipenem/cilastatin monotherapy (treatment group) versus cefazolin plus ceftazidime (control group) in the treatment of PD peritonitis. The result was further compared to a historic group treated with cefazolin plus netilmycin. Outcome measures were primary response rate at day 10 and complete cure rate. RESULTS: We enrolled 51 patients in the treatment group, 51 in the control group, and identified 96 in the historic group. The primary response rate to the assigned antibiotics was 49.0%, 51.0%, and 49.0% for the treatment, control, and historic groups, respectively (p = 0.97). The primary response rate allowing for change in antibiotic was 82.4%, 90.2%, and 82.3%, respectively, for the three groups (p = 0.41). The complete cure rate was 72.5%, 80.4%, and 82.3%, respectively (p = 0.60). Tenckhoff catheter removal was needed in 6 cases in the treatment group, 6 cases in the control group, and 13 cases in the historic group (p = 0.90). CONCLUSIONS: We concluded that monotherapy of imipenem/cilastatin has similar efficacy compared to the two standard regimens of cefazolin plus ceftazidime or netilmycin in the treatment of PD peritonitis. 相似文献
43.
44.
Bone marrow fat content in relation to bone remodeling and serum chemistry in intact and ovariectomized dogs 总被引:6,自引:0,他引:6
R. Bruce Martin Ph.D. Betty D. Chow Paul A. Lucas 《Calcified tissue international》1990,46(3):189-194
Summary It was previously shown that 11 months after ovariectomy the volume fraction of trabecular bone in the spine and 11th rib
medullary canal of Beagle dogs (6 control, 9 ovariectomized) was significantly reduced. In this paper it is shown that these
changes are accompanied by increased marrow fat volume in the 11th rib (59.0±9.5% vs. 44.3 ±10.0%). Conversely, the volume
fraction of functional (hematopoietic) cells in the marrow was reduced by ovariectomy. Additionally, variations in marrow
fat volume were tested for correlation with 22 other variables pertinent to bone physiology. Marrow fat volume was significantly
positively correlated with serum osteocalcin, rib trabecular bone porosity, rib cross-sectional area, and gains in body weight.
It was negatively correlated with serum estrogen concentrations and the extent of rib trabecular surfaces labeled with tetracycline. 相似文献
45.
A previous study showed that a two-solution fluoride (F) rinse deposited significantly more loosely-bound F on the tooth surface than did a sodium fluoride (NaF) rinse with the same F concentration (12 mmol/L). In the present study, this experimental rinse was evaluated for its ability to cause remineralization of enamel lesions in an in vitro pH-cycling model. Caries-like lesions were formed in the enamel of extracted human molars by means of a pH 4 demineralizing solution. Fifty-one approximately 120-microns-thick sections containing lesions were randomly divided into (1) control, (2) NaF rinse, and (3) two-solution F rinse groups. With the cut surfaces protected, the control samples were immersed in a pH 7 remineralizing solution for 12 days, and twice daily the sections were also exposed to a pH 4 demineralizing solution for 30 min. Samples in the NaF group received an additional one-minute rinse with a NaF (12 mmol/L) solution twice daily. Samples in the two-solution rinse group received the rinse treatment with a 12 mmol/L F solution prepared by combination of a Na2SiF6 and phosphate-containing solution with a calcium solution just before use. The mineral contents of the lesions were assessed by quantitative microradiography. The results showed that (1) no significant de- or remineralization was detected in the controls; (2) a 46% decrease in mineral loss (delta Z) of the lesion was produced by the NaF rinses; and (3) a 94% decrease in delta Z and a 20-microns-thick, mineral-dense surface-coating were produced by the two-solution F rinse treatment. 相似文献
46.
47.
An assessment of immunoreactive epidermal growth factor in urine of patients with urological diseases 总被引:1,自引:0,他引:1
N. H. Chow T. -S. Tzai P. -E. Cheng C. -J. Chang J. S. -N. Lin M. -J. Tang 《Urological research》1994,22(4):221-225
To examine the excretion of urinary epidermal growth factor (EGF) in urological diseases and the relationship of EGF urine levels with transitional cell carcinoma (TCC), we measured the concentration of EGF by radioimmunoassay. The series comprised patients with active TCC (n=50), others in tumor-free status (n=29) and with non-neoplastic inflammatory diseases (n=43), and normal controls (n=50). Urinary EGF values were lower in patients with urological diseases of different etiologies than in normal controls (P<0.005). Mean EGF levels of patients who had previous bladder tumor resection (n=21) were not statistically different from normal controls (P=0.2). For patients with active TCC, EGF urine levels showed a significant inverse relationship to increasing tumor grade (P=0.02). In addition, subjects who had received nephrectomy for pelvic carcinoma (n=8) showed significantly lower mean EGF values than those with intact kidneys (n=21), irrespective of sex (P<0.05). Immunostaining of EGF on non-neoplastic kidney (n=9) revealed reactivity in the distal convoluted tubules and thick ascending limbs of Henle. Our results suggest that the kidney is the major source of urinary EGF. Its excretion in urine is decreased in both inflammatory and neoplastic diseases of the urinary tract. EGF may play an important part in the biological activity of TCC. Further study is indicated to investigate the monitoring of EGF urine levels as a marker of recurrence for EGF receptor-positive TCC. 相似文献
48.
49.
Jean M. Panneton MD Peter Gloviczki MD Linda G. Canton RN BSN Thomas C. Bower MD Matthew S. T. Chow MD Peter C. Pairolero MD Hartzell V. Schaff MD John W. Hallett Jr. MD Kenneth J. Cherry Jr. MD 《Annals of vascular surgery》1996,10(2):97-108
Renal transplantation has increased the longevity of patients with uremia. An increasing number undergo aortic reconstruction, which exposes the transplanted kidney to ischemic injury. To evaluate the risk for renal failure, loss of the transplant, and methods of renal protection, we reviewed our experience. Clinical data were reviewed for 10 consecutive patients (7 men, 3 women; mean age 52.7 years [range 32 to 75 years]) with a transplanted kidney who underwent aortic reconstruction between 1977 and 1994 at our institution. Mean interval between renal transplantation and aortic reconstruction was 5.9 years (range 1 month to 12.7 years). Seven patients required emergency repair because of dissection (2 patients), aneurysm rupture (4 patients), or symptomatic aneurysm (1 patient); three underwent elective repair. Reasons for reconstruction included aortic dissection (2 patients), aneurysm of the descending thoracic (2 patients), thoracoabdominal (1 patient), or abdominal aorta (3 patients), and aortoiliac occlusive disease (2 patients). Patients with thoracic or thoracoabdominal reconstructions underwent repair with atriofemoral, aortofemoral, or femorofemoral shunt placement or bypass. Of the five abdominal aortic reconstructions, the kidney was protected with aortofemoral shunt placement in one patient and cold renal perfusion in three. In two of them, topical cooling of the kidney also was used. One patient with acute aortic dissection died at 39 days as a result of respiratory failure. Loss of the recently transplanted kidney was caused by acute rejection. One patient had a transient increase in serum creatinine concentration. Eight had no worsening of renal function, and none of the nine survivors lost the transplanted kidney. We conclude that aortic reconstruction can be safely performed in kidney transplant recipients. Patients in whom thoracic or thoracoabdominal aortic reconstruction was required were protected with an atriofemoral or aortofemoral bypass or shunt. Patients undergoing abdominal aortic reconstruction did well when cold renal perfusion with or without local cooling of the transplant was used for renal protection. Transplanted kidneys appeared to tolerate ischemic injury similarly to native kidneys.Presented at the Twentieth Annual Meeting of the Peripheral Vascular Surgery Society, New Orleans, La., June 10, 1995. 相似文献
50.
Radiation treatments using low energy X-rays or electrons frequently require a final field defining shield to be placed on the patient's skin. A custom made lead cut-out is used to provide a close fit to a particular patient's surface contours. We have developed a procedure which utilizes POLYFORM thermoplastic to obtain a negative mold of the patient instead of the traditional plaster bandage or dental impression gel. The Polyform is softened in warm water, molded carefully over the patient's surface, and is removed when "set" or hardened, usually within five minutes. Then lead sheet cut-outs can be formed within this negative. For shielding cut-outs requiring thicker lead sheet, a positive is made from dental stone using this Polyform negative. We have found this procedure to be neat, fast and comfortable for both patient and the dosimetrist. 相似文献