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21.
International Urology and Nephrology - To determine predictors for surgical complications and assess patient satisfaction after surgical treatment of Adult-Acquired Buried Penis (AABP). A...  相似文献   
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This brief report describes an asymptomatic patient with a myocardial mass. Two-dimensional echocardiography, technetium Tc 99m cardiac nuclear scan, and transesophageal echocardiography were performed to define the mass. The mass, which involved the subvalvar right ventricular free wall, was resected and determined to be a metastatic carcinoid tumor by histologic and immunohistochemical analysis. Further investigation revealed the presence of a midgut carcinoid tumor located within the terminal ileum, which was also resected surgically. The patient recovered well after surgery and adjunctive chemotherapy. To our knowledge, this is the first report of comprehensive nuclear and echocardiographic imaging, supplemented by surgical and pathologic findings, in an asymptomatic patient with isolated myocardial metastasis of an ileal carcinoid tumor.  相似文献   
24.
The ability of d,l-propranolol to block renin secretion in response to various extrarenal stimuli, such as hemorrhage and hypoglycemia, has been interpreted to indicate the presence of an intrarenal beta receptor regulating renin release. However, two problems complicate this interpretation: (a) the stimuli have effects outside the kidney, and (b) d,l-propranolol has a local anesthetic, as well as a beta adrenergic blocking, action. In the present study, the effects of a purely intrarenal stimulus, in the form of renal nerve stimulation (RNS), on renin secretion was examined. The effects of d,l-propranolol (anesthetic and beta-blocking activity), l-propranolol (beta-blocking activity only), and d-propranolol (local anesthetic activity only) on the renin response to RNS were examined. In a control group of animals, two sequential RNS increased mean renin secretion from 401 to 1,255 U/min (P less than 0.25) and from 220 to 2,179 U/min (P less than 0.01). In a second group the first RNS increased renin secretion from 201 to 1,181 U/min (P less than 0.01), but after d,l-propranolol was given RNS did not significantly alter renin secretion (33 to 55 U/min). In a third group the initial RNS increased renin secretion from 378 to 1,802 U/min (P less than 0.025), but after l-propranolol was given RNS had no significant effect on renin secretion (84 to 51 U/min). A fourth group of dogs showed a rise in renin secretion from 205 to 880 U/min (P less than 0.001) in response to the first RNS, while the second RNS, given after an infusion of d-propranolol, caused a rise in renin secretion from 80 to 482 (P less than 0.005). The nature of the electrical stimulus was consistent in all groups and caused no detectable changes in renal or systemic hemodynamics or in urinary electrolyte excretion. The results, therefore, indicate that renin secretion can be stimulated through intrarenal beta receptors independent of changes in systemic or renal hemodynamics or in tubular sodium reabsorption. Hence the effect of beta stimulation on renin secretion would appear to result from a direct action on the renin-secreting cells of the juxtaglomerular apparatus.  相似文献   
25.
In myotonic muscular dystrophy, abnormal muscle Na currents underlie myotonic discharges. Since the myotonic muscular dystrophy gene encodes a product, human myotonin protein kinase, with structural similarity to protein kinases, we tested the idea that human myotonin protein kinase modulates skeletal muscle Na channels. Coexpression of human myotonin protein kinase with rat skeletal muscle Na channels in Xenopus oocytes reduced the amplitude of Na currents and accelerated current decay. The effect required the presence of a potential phosphorylation site in the inactivation mechanism of the channel. The mutation responsible for human disease, trinucleotide repeats in the 3' untranslated region, did not prevent the effect. The consequence of an abnormal amount of the kinase would be altered muscle cell excitability, consistent with the clinical finding of myotonia in myotonic dystrophy.  相似文献   
26.
The recognition of abnormal lipoprotein metabolism that produces chronic hypocholesterolemia in myeloproliferative disorders and the known influence of altered plasma lipid levels on erythrocyte membranes prompted a study of erythrocyte susceptibility to lipid peroxidation in myeloproliferative disease. Malonyldialdehyde generation during an oxidant challenge of erythrocyte suspensions of standardized hemoglobin concentration with H2O2 was significantly greater in 32 patients with myeloproliferative disease than in 47 hematologically normal subjects. The myeloproliferative disease group had significantly lower plasma total, HDL-, and LDL-cholesterol, erythrocyte indices, and erythrocyte deformability, and higher reticulocyte counts and serum lactic dehydrogenase. In the myeloproliferative disease group, mean corpuscular hemoglobin concentration, reticulocyte count, and erythrocyte count were significant variables in accounting for the observed variation in peroxidation susceptibility. Erythrocytes of patients with myeloproliferative disease had elevated concentrations of reduced glutathione, normal glutathione stability, and normal alpha-tocopherol content. These studies demonstrate increased susceptibility to oxidative damage in myeloproliferative disease despite normal or increased concentrations of the major antioxidant compounds of the erythrocyte. The presence of reticulocytosis, elevated serum lactic dehydrogenase, and decreased erythrocyte deformability suggests that lipid peroxidation susceptibility is associated with in vivo hemolysis and may contribute to the anemia that complicates myeloproliferative disease.  相似文献   
27.
We developed a new reporter cell line for human cytomegalovirus (HCMV) drug susceptibility testing. This cell line was obtained by incorporating the luciferase reporter gene under the control of an HCMV-specific promoter into the genome of astrocytoma cells (U373MG). We then used our reporter cell line to evaluate phenotypic changes conferred by the sequential emergence of HCMV UL54 and UL97 mutations following long-term drug exposure. The laboratory strain AD169 was passaged in the presence of increasing concentrations of ganciclovir (one viral line) or foscarnet (two viral lines). Resistant viruses were plaque purified at five different concentrations of ganciclovir and at three different concentrations of foscarnet. In addition to the previously described M460I and L595S UL97 mutations and the L545S and V812L UL54 mutations, exposition to ganciclovir (up to 3,000 microM) resulted in the selection of two unreported UL54 mutations (P829S and D879G). Passages in the presence of foscarnet (up to 3,000 microM) resulted in the selection of seven not previously described UL54 mutations (K500N, T552N, S585A, N757K, L802V, L926V, and L957F) in addition to the N408D mutation that has been associated with ganciclovir and cidofovir resistance. Long-term exposure of HCMV to either ganciclovir or foscarnet ultimately resulted in the selection of multiple UL54 mutations that conferred high levels of resistance to all approved HCMV DNA polymerase inhibitors, i.e., ganciclovir, cidofovir, and foscarnet. Emergence of each viral mutation conferred stepwise increases in drug 50% inhibitory concentrations that could be objectively measured with the new reporter cell assay.  相似文献   
28.

Background

Esthetics represents an inseparable part of today''s oral therapy, and several procedures have been proposed to preserve or enhance it. Gingival recessions may cause hypersensitivity, impaired esthetics and root caries. Keeping in mind patient''s desire for improved esthetics and other related problems, every effort should be made to achieve complete root coverage.

Methods

Different types of modalities have been introduced to treat gingival recession including displaced flaps, free gingival graft, connective tissue graft, different type of barrier membranes and combination of different techniques. The aim of this study was to compare the commonly used techniques for gingival recession coverage and evaluate the results obtained. 73 subjects were selected for the present study who were randomly divided into four groups and were followed at baseline and 180 days where following parameters were recorded: (a) Assessment of gingival recession depth (RD); (b) Assessment of pocket depth (PD); (c) Assessment of clinical attachment level (CAL) and (d) Assessment of width of attached gingiva (WAG).

Results

Results of this study showed statistically significant reduction of gingival recession, with concomitant attachment gain, following treatment with all tested surgical techniques. However, SCTG with CAF technique showed the highest percentage gain in coverage of recession depth as well as gain in keratinized gingiva. Similar results were obtained with CAF alone. The use of GTR and other techniques showed less predictable coverage and gain in keratinized gingiva.

Conclusion

Connective tissue grafts were statistically significantly superior to guided tissue regeneration for improvement in gingival recession reduction.  相似文献   
29.
The healthy vaginal microbiota is generally dominated by lactobacilli that confer antimicrobial protection and play a crucial role in health. Bacterial vaginosis (BV) is the most prevalent lower genital tract infection in women in reproductive age and is characterized by a shift in the relative abundances of Lactobacillus spp. to a greater abundance of strictly anaerobic bacteria. In this study, we designed a new phylogenetic microarray-based tool (VaginArray) that includes 17 probe sets specific for the most representative bacterial groups of the human vaginal ecosystem. This tool was implemented using the ligase detection reaction-universal array (LDR-UA) approach. The entire probe set properly recognized the specific targets and showed an overall sensitivity of 6 to 12 ng per probe. The VaginArray was applied to assess the efficacy of rifaximin vaginal tablets for the treatment of BV, analyzing the vaginal bacterial communities of 22 BV-affected women treated with rifaximin vaginal tablets at a dosage of 25 mg/day for 5 days. Our results showed the ability of rifaximin to reduce the growth of various BV-related bacteria (Atopobium vaginae, Prevotella, Megasphaera, Mobiluncus, and Sneathia spp.), with the highest antibiotic susceptibility for A. vaginae and Sneathia spp. Moreover, we observed an increase of Lactobacillus crispatus levels in the subset of women who maintained remission after 1 month of therapy, opening new perspectives for the treatment of BV.  相似文献   
30.
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