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1.
The authors describe their experience with methyl tertiary butyl ether (MTBE) in a larger series of patients than previously reported in order to acquaint physicians with both its effectiveness for dissolution of common bile duct calculi and the limitations of its use. Ten patients with 13 biliary calculi underwent percutaneous stone dissolution treatment with the experimental cholesterol solvent, MTBE. Three stones completely dissolved within 30 minutes, seven were reduced in size, and three were visibly unaffected. All stones not completely dissolved were easily extracted by means of a stone basket except for one in a patient taken to surgery. Although MTBE perfusion is an effective technique for management of biliary calculi, practitioners should be aware that its use is quite time consuming and its odor difficult to control.  相似文献   
2.
β-Lactoglobulin was isolated from infant formulae that were ultra high temperature (UHT) -treated, sterilized or spray-dried. The effect of the isolated β-lactoglobulin on SfaII-fimbriae-mediated adhesion of Escherichia coli to human ileostomy glycoproteins was studied in vitro. β-Lactoglobulin isolated from sterilized formulae was found to perform significantly less well than preparations from spray-dried formulae (p = 0:05). Great heterogeneity was observed in the adhesion inhibitory capacity of β-lactoglobulin isolated from UHT-treated formulae. Therefore, no significant difference was observed between UHT-treated and sterilized formulae or spray-dried formulae (p < 0:10). It can be hypothesized that β-lactoglobulin from spray-dried and some UHT-treated infant formulae may affect the colonization of mucous membranes by E. coli strains causing neonatal septicaemia and meningitis.  相似文献   
3.
The characteristic of malignant pleural mesothelioma is a tumor that grows by plate-like extension over the pleura, and invades adjacent tissues and organs. Radical surgical removal of the tumor is generally not possible, and most treatment regimens involve combined chemotherapy and radiotherapy, as well as debulking surgery. We have prospectively evaluated five locally-aggressive multi-modality treatment programs, using different hemithorax irradiation schedules and chemotherapy regimens. One hundred patients with confirmed malignant pleural mesothelioma entered the study between 1977 and 1989. The treatment programs, which can consecutively, were: I, 20 Gy (10 x 2 Gy) to the hemithorax + CYVADIC (cyclophosphamide 500 mg/m2 d 1, vincristine 1 mg/m2 d 1 and 5, adriamycin 40 mg/m2 d 1 and dacarbazine 200 mg/m2 d 1 and 5, several cycles before and after irradiation); II, 55 Gy (25 x 2.2 Gy) to the hemithorax + 15 Gy (6 x 2.5 Gy) to the tumor + CYVADIC (2 cycles before, 1 cycle during, and 2 cycles after irradiation); III, Mitoxantrone (14 mg/m2 q 28 d, < or = 6 cycles) followed by 70 Gy (56 x 1.25 Gy, twice a day); IV, 4-Epirubicin (110-130 mg/m2 q 28 d, < or = 6 cycles) followed by 35 Gy (28 x 1.25 Gy twice a day) to the hemithorax + 36 Gy (9 x 4 Gy every 2 days) to the tumor; V, Etoposide (150 mg/m2 1, 3, 5 q 28 d) followed by 38.5 Gy (11 x 3.5 Gy) to the hemithorax. A new system for evaluating tumor response in pleural mesothelioma was applied. None of the combined treatment programs prevented local invasive growth or the spread of mesothelioma outside the hemithorax. The median survival time was slightly increased from 8 to 12 months for those patients who completed the protocol treatments, but progressive disease was the invariable outcome. Radiation pneumonitis and fibrosis were severe and compatible with results of total loss of lung function on the irradiated side. We conclude that data relating to therapeutic responses and treatment programs in malignant mesothelioma should be better correlated internationally, if the problems associated with the evaluation of treatment and the management of patients with mesothelioma are to be improved.  相似文献   
4.
Intestinal obstruction proximal to a transition zone without an interposed physical barrier usually indicates Hirschsprung disease. The authors report one case of focal small bowel muscular thinning just distal to a transition zone that produced clinical and radiographic findings that simulated long-segment Hirschsprung disease in a 2-day-old infant.  相似文献   
5.
Image-directed percutaneous biopsies with a biopsy gun   总被引:3,自引:0,他引:3  
Core tissue for histologic study is believed by many pathologists to be more diagnostic than material from needle aspiration. Recently, a biopsy "gun" has been introduced, which simplifies core biopsies. With this device, 182 biopsies of multiple anatomic sites were performed with ultrasonic, computed tomographic, and fluoroscopic guidance and 18-gauge needles. High-quality histopathologic specimens were obtained in 177 of the biopsies, and diagnostic target tissue was obtained in 167. Only three significant complications occurred: one bleeding complication that required transfusion and two cases of pneumothorax that necessitated placement of chest tubes. The biopsy gun eliminated the disjointed movements of conventional "skinny" needle biopsies, and none of the samples demonstrated significant "crush" artifact or obscuring blood, problems that are commonly associated with manual biopsy techniques. Patient discomfort was decreased with this system compared with that of manual biopsies, and the total procedure time was reduced. Because of these distinct advantages, the authors now use the biopsy gun exclusively for all percutaneous biopsies and recommend that other institutions consider the use of this biopsy method.  相似文献   
6.
An earlier study has indicated that a complex recombinant HIV-1 strain dominates the epidemic in Estonia. The objective of this study was to further investigate the molecular epidemiology and genetic structure of HIV-1 in Estonia. Most of the investigated individuals became infected after August 2000 when HIV-1 started to spread rapidly among Estonian intravenous drug users (IDUs). Two viral DNA regions, gag/pol and gp41, were sequenced and subtyped from peripheral blood mononuclear cells or plasma from 141 individuals. Phylogenetic analysis in the gp41 region revealed that the most frequent type of the virus among IDUs was a circulating recombinant form, CRF06_cpx, whereas a few samples showed highest sequence similarity to a subtype A strain circulating in Ukraine and Russia. Likewise, in the gag/pol region, most of the samples were classified as CRF06_cpx, with a few classified as subtype A. In this region, however, 16% of the sequences turned out to be mosaic unique recombinant forms consisting of CRF06_cpx and subtype A. At least 9 mosaic forms were identified, each with distinct patterns of multiple crossover. To characterize Estonian CRF06_cpx as well as recombinant isolates in more detail, 4 near-full-length HIV-1 genomes were sequenced.  相似文献   
7.
Vascular adhesion protein-1 (VAP-1) is an endothelial adhesion molecule mediating leukocyte interactions with blood vessels during leukocyte extravasation. Molecularly VAP-1 is a cell-surface-expressed ecto-enzyme belonging to the group of semicarbazide-sensitive amine oxidases (SSAO; EC 2.4.6.3), which deaminate primary amines. Here we asked whether peptides displaying a suitable free amine group could be a substrate or inhibitor of SSAO and thus regulate VAP-1-mediated leukocyte adhesion. On the basis of a molecular model of VAP-1, we designed synthetic peptides that fit to the substrate channel of VAP-1. One of these lysine-containing peptides effectively inhibits VAP-1-dependent lymphocyte rolling and firm adhesion to primary endothelial cells under physiologically relevant shear conditions. The same peptide inhibits the SSAO activity of endothelial and recombinant VAP-1 in a selective and long-lasting manner. We also show that all enzymatically active VAP-1 is displayed on the cell surface. Our results suggest that, in addition to soluble amines, specific cell-surface-bound molecules containing free NH(2) groups in a suitable position may modulate the enzymatic activity of SSAO. Moreover, the inhibitory peptide diminishes leukocyte interactions with endothelial cells under conditions of shear, and thus it may be useful to treat inflammatory conditions.  相似文献   
8.
For reliable classification of HIV-1 strains appropriate reference sequences are needed. The HIV-1 genetic subtype F has a wide geographic spread, causing significant epidemics in South America, Africa, and some regions of Europe. Previously only two full-length sequences of each of the HIV-1 subtype F subclusters F1 and F2 have been described. To extend the knowledge of subtype F variation on a complete genome level, three new virtually full-length F1 sequences were cloned and sequenced, two from Africa and one from South America. Comparison of the new and previously described sequences showed that monophyletic clustering of the subcluster F1 of subtype F is consistent and highly supported in all genome regions. Two additional full-length strains were shown to be mosaics of subtypes F and D. These epidemiologically unrelated F/D sequences showed similar chimeric structure, suggesting that they may represent a previously undescribed circulating recombinant form (CRF). This was supported by partial sequences from three additional unlinked F/D recombinants. Genetic distances in the phylogenetic trees suggest that the recombination event leading to the putative CRF occurred relatively long ago, close to the divergence of the F1 and F2 subclusters. Furthermore, all five F/D recombinants are linked to the Democratic Republic of Congo, suggesting that the original recombination event took place in central Africa.  相似文献   
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