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71.
PURPOSE: Although they are therapeutically effective, injectable materials for urinary tract are associated with various disadvantages, precluding their universal acceptance. In this study we investigated glass spheres (GSs) as an alternative injectable substance to correct vesicoureteral reflux (VUR) in an animal model. MATERIALS AND METHODS: We used 150 to 300 micro GSs suspended in agarose gel to form the injection paste. GS paste was injected into the rectus muscle and submucosa of the bladder in 8 adult New Zealand male rabbits. As a control group, vehicle only was injected into 4 rabbits. The rabbits were sacrificed to harvest the bladder, pelvic lymph nodes, kidney, liver, brain, spleen and lung at month 1 and year 1 of injection. A VUR model was then created by unroofing the 2 ureteral orifices of 12 adult sheep. GS paste was injected into the right subureter and vehicle only was injected into the left subureter. Cystourethrographies were performed at month 3 and year 1 of injection. The sheep were sacrificed at cystourethrography to harvest the bladder, lymph nodes, kidney, liver, brain, spleen and lung. RESULTS: At month 3 and year 1 of injection into rabbit tissues nodule formation was stable in position and volume. Histopathological studies of local and distant organs of the rabbit did not show any granuloma formation or migration of GS. GS paste injection corrected VUR in sheep. Re-injection of GS into still refluxing left units corrected VUR. Local and distant organs harvested from sheep did not demonstrate distant migration. CONCLUSIONS: When injected into bladder submucosa and rectus muscle, GS appears to be inert, biocompatible and efficient. Similarly it is effective for correcting VUR in an animal model. We present our data on GS, encouraging further investigation to develop an alternative injectable material for endoscopic VUR correction.  相似文献   
72.
BACKGROUND: Adequate care of a hemodialysis patient requires constant attention to the need to maintain vascular access (VA) patency. VA complications are the main cause of hospitalization in hemodialysis patients. The native arteriovenous fistula (NAVF), synthetic arteriovenous grafts fistula (GAVF) and silastic cuffed central venous catheters (CVCs) are used for permanent vascular access (PVA). CVCs are primary the method of choice for temporary access. But using this access modality is increasing more and more for PVA in elderly hemodialysis patients and when other PVA is not possible. The primary aim of this study is to investigate survivals and complications of the CVCs used for long-term VA. METHODS: We prospectively looked at 92 CVCs (Medcomp Ash Split Cath, 14 FR x 28 cm (Little, M.A.; O'Riordan, A.; Lucey, B.; Farrell, M.; Lee, M.; Conlon, P.J.; Walshe, J.J. A prospective study of complications associated with cuffed, tunnelled hemodialysis catheters. Nephrol. Dial. Transplant. 2001, 16 (11), 2194-2200) with Dacron cuff) inserted in 85 (50 females, 35 males) chronic hemodialysis patients (the mean age: 56.6 +/- 14.1 years) from July 1999 to January 2002. The overall survival and complications were followed up. Furthermore, the patients were evaluated for demographic and clinical characteristics. Data were analysed by chi-square, Wilcoxon rank and Kaplan-Meier survival tests. RESULTS: The median duration of CVC survival was 289 days (range: 10-720). Eleven (11.9%) CVCs were removed due to complications. In 79 (92.9%) patients, 1, in 5 (5.8%) patients, 2 and in 1 patient, 3 CVCs were inserted. Of the 85 patients, 56 have CVCs functioning. In addition, 27 (31.76%) patients have CVCs functioning for over 12 months, 17 (20%) patients have CVCs functioning for 6 months. The total incidence of CVC related infections was 0.82 episodes/1000 catheter days. Besides, thrombosis was occurred in 10 (10.8%) CVCs. The most frequent indications for CVC removal were patient death (69.4%), thrombosis (16.6%) and CVC-related infections (13.8%). CONCLUSIONS: CVCs are primarily used for temporary access. But this study indicates that CVC may be a very useful alternative permanent vascular access for hemodialysis patients when other forms of vascular access are not available.  相似文献   
73.
We conducted three prospective studies of Haemophilus influenzae in different groups of children. Pharyngeal swab samples were taken (i). from 1382 healthy infants and children between 0 and 10 years of age (group 1), attending well child clinics (n=438), day care centres (n=440) and elementary schools (n=504), and (ii). from 322 children aged 2-10 years (group 2), clinically diagnosed as having upper respiratory tract infection. Pharyngeal swab samples and sinus aspirates were obtained from 49 children between 2 and 9 years of age (group 3), clinically diagnosed as having sinusitis. H. influenzae was isolated in similar rates from 315 (22.7%) of children in group 1, 72 (22.3%) of children in group 2 and 12 (24.4%) of children in group 3. Serotype b comprised 7, 5.2 and 2% of all H. influenzae isolates for group 1, 2 and 3, respectively. Production of beta-lactamase was detected in 1.0% of H. influenzae type b isolates in group 1, 1.2 and 6.1% of all isolates in group 2 and 3, respectively. There were no beta-lactamase negative ampicillin-resistant strains.  相似文献   
74.
PURPOSE: The purpose of this study was to determine the value of the intraoperative gamma probe and the efficacy of dual-phase Tc-99m sestamibi imaging in patients with primary hyperparathyroidism. METHODS: Twenty-one patients with primary hyperparathyroidism were examined prospectively. Results of same-day dual-phase Tc-99m sestamibi scintigraphy and intraoperative gamma probe evaluations were compared with the intraoperative findings and histopathologic diagnoses. A 15-mm handheld gamma probe was used to measure gamma activity in the neck and upper mediastinum. Nuclear mapping by gamma probe showed a single quadrant of neck that emitted gamma radiation significantly greater than the other three quadrants, which correlated with the sestamibi scan. RESULTS: Dual-phase Tc-99m sestamibi scintigraphy determined and localized parathyroid lesions in 20 patients (sensitivity, 94%). Of the 20 parathyroid lesions removed, 15 were located in normal positions, whereas five were explored in ectopic sites (one within the thyroid, one in the anterior mediastinum, one in a retrotracheal position, one in the carotid sheath, and one in the retroesophageal region). Although the index of thyroid nodules varied from 15.8% to 22.9%, the index for parathyroid lesions was 77.3% to 112.8%. CONCLUSIONS: These results confirm that parathyroid lesions, especially at ectopic sites, can be treated successfully in shorter operative times with minimal complications with the help of the intraoperative gamma probe.  相似文献   
75.
AIM: The aim of this study is to report the effectiveness of selective endovascular embolization with N-butyl cyanoacrylate (NBCA) in the treatment of traumatic intrarenal arterial pseudoaneurysms. MATERIALS AND METHODS: Five patients (four males and one female) presented with massive haematuria. Five pseudoaneurysms were detected angiographically, and in all of the cases the aetiology was penetrating trauma. The pseudoaneurysms ranged in size between 7 and 30 mm (mean: 13.8 mm). After the superselective catheterization with a microcatheter-microguidewire system, embolization was performed using NBCA and Lipiodol mixture. RESULTS: All the pseudoaneurysms were successfully embolized and excluded from the circulation without any other major intrarenal arterial branch occlusion. There were no major or minor complications related to the embolization procedures. Haematuria ceased in 1-3 days after the embolization, and during the follow-up period both re-bleeding and deterioration of renal function did not occur. CONCLUSION: The endovascular management of renal artery branch pseudoaneurysms by embolization with NBCA is a reasonable and an effective therapeutic technique.  相似文献   
76.
Secondary amyloidosis (AA amyloidosis) is a well known cause of nephrotic syndrome and renal failure. Several studies in patients with nephrotic syndrome have suggested a beneficial effect of angiotensin-converting enzyme inhibitors (ACEI). Angiotensin II (ATII) receptor antagonists effect on the long term is not known. In this study, we intended to study the effect of losartan, as an ATII receptor antagonist, on proteinuria and renal functions in patients with normotensive secondary amyloidosis. In total 44 patients with biopsy proven AA amyloidosis associated with nephrotic proteinuria were included. The first group of patients (n=22) was treated with losartan 50 mg/day. The second group of patients (n=22) did not receive any specific antiproteinuric treatment. Urinary protein loss was effectively lowered by losartan from 4.38 +/- 1.0 to 2.8 +/- 0.61 g/day (p<0.0001), whereas the control group showed a slight fall in proteinuria as 4.21 +/- 1.06 to 4.12 +/- 1.07 g/day (p = 0.176). Hypoalbuminemia improved significantly from 2.52 +/- 0.69 to 2.78 +/- 0.46 g/dl (p = 0.004), in the losartan group, whereas serum albumin had fallen in the control group from 2.44 +/- 0.57 to 2.27 +/- 0.41 (p = 0.041). Serum creatinine increased in the control group from 1.52 +/- 0.42 to 2.39 +/- 0.51 mg/dl (p<0.0001), and in the losartan group from 1.59 +/- 0.50 to 1.84 +/- 0.6 mg/dl (p<0.001), after 24 months of treatment. The ATII receptor blocker losartan is effective in protecting against the progression of nephropathy due to AA amyloidosis. Symptomatic treatment of proteinuria with losartan is therefore to be considered, especially with severe proteinuria even in normotensive patients.  相似文献   
77.
78.
The aim of this study is to evaluate the impact of ovarian reserve and age of women on early morphokinetic parameters of embryos with a time-lapse monitoring system. In total, 197 infertile couples with poor ovarian reserve (Group 1, n?=?41), normal ovarian reserve (Group 2, n?=?59), or polycystic ovaries (Group 3, n?=?97) were included. The time from insemination to the following events were analyzed: pronuclear fading (Pnf) and cleavage to 2, 3, 4 and 5 cells. The optimal ranges for morphokinetic parameters of t5, s2 and cc2 in each group were also evaluated. In total, 1144 embryos were evaluated. Morphokinetic parameters did not differ statistically between the groups. Data were analyzed according to different age groups (20–30, 30–40,?>40). The morphokinetic parameters did not differ statistically in Group 1 and 3. In Group 2, the times from insemination to tPnf, t2, t3, t4 were significantly shorter in the younger age group than the older age group (p?相似文献   
79.
Novel six Cu(II), Ni(II), and Zn(II) complexes with Schiff bases derived from 4-aminobenzoic acid with terephtaldehyde and amino acids (glycine, β-alanine). Structures have been proposed from elemental analysis, UV–Vis, IR, NMR, TGA, DTA, and magnetic measurements. Spectroscopic studies suggest that coordination occurs through azomethine nitrogen, hydroxyl group, and carbonyl oxygen of the ligands to the metal ions. The elemental analyses of the complexes where L is Schiff base ligands, are confined to the stoichiometry of the type M2L2(CH3COO)2 [M = Cu(II)]; and M2L(CH3COO)2 [M = Ni(II) and Zn(II)]. The cytotoxicity activities of the compounds against human breast carcinoma MCF-7 cell line have been studied. Ligands and their Zn(II) compounds inhibited cell proliferation of MCF-7 cancer cell lines in a dose- and time-dependent manner. The free radical scavenging activity was measured by 1,1-diphenyl-2-picryl-hydrazil. Our results show that the synthesized compounds induced oxidative damage by increasing the lipid peroxidation in yeast since MDA formation was increased, and it could be concluded that the synthesized compounds caused oxidative stress. In addition, the antioxidant activities of the synthesized compounds were very much lower than those of standard antioxidants.  相似文献   
80.
Purpose  To evaluate the efficacy of topical cyclosporin A 0.05% in managing the symptoms of severe vernal keratoconjunctivitis (VKC). Methods  Fifty-four children with severe VKC were included in this study. All 54 patients were treated with topical cyclosporin A (CsA) 0.05% for 3 months. Ocular signs and symptoms were scored in all patients at entry and after 3 months. Conjunctival impression cytology specimens were examined on the day of enrollment and at the end of the treatment period. Results  The mean scores for severity of signs and symptoms significantly decreased after 3 months compared with those at entry (P < 0.001). The density of inflammatory cells in the conjunctival impression cytology specimens decreased significantly. No side effects of the treatment with CsA 0.05% eyedrops were observed. Conclusions  Topical CsA 0.05% eyedrops were found to be safe and effective in the treatment of patients with VKC. Consistent with these results, topical CsA may efficiently reduce conjunctival inflammation in severe VKC.  相似文献   
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