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101.
Over a 3-year-period, standard treatment with hydrostatic pressure from a contrast enema failed to reduce ileocolic intussusception in 31 of 62 children. With the child anesthetized in the operating room, a second contrast enema was given before laparotomy. Of the 31 intussusceptions, 21 (68%) were reduced without complication, thereby avoiding the discomfort, longer hospitalization, complications, and expense of surgery. Nine of the remaining 10 intussusceptions were difficult to reduce manually during surgery or required resection. The overall nonoperative reduction rate for the 3-year period was 84%; for the last 2 years it was 90%. Success with the second enema may be related to the effects of general anesthesia. In addition, partial reduction with the first enema may improve blood flow from the intussusceptum so that it becomes smaller and easier to reduce with the second enema. Because it can easily be added to standard management protocols without increased risk, routine use of this second enema with anesthesia is recommended.  相似文献   
102.
Photometric determination of phospholipase A   总被引:2,自引:0,他引:2  
A photometric method for the determination of phospholipase A is described, in which fatty acids are liberated from phosphatidylcholine and measured by a discontinuous enzymatic test. Optimal test conditions were evaluated using purified phospholipase A from human and porcine pancreas. The enzyme activities measured in normal human sera are in the range of 0 to 10 U/l. Pathological values reach more than 100 U/l. There is no correlation with the activities of lipase or amylase in cases of acute pancreatitis.  相似文献   
103.
BACKGROUND: Signet-ring cells are formed by intracytoplasmic accumulations of various substances that push the nucleus to the cellular border. Signet-ring cells in epithelial neoplasms are often regarded as evidence of adenocarcinoma. OBJECTIVE: The study surveys the rare settings in which signet-ring cells are encountered in dermatopathologic specimens and investigates mechanisms of their formation. METHODS: A total of 23 cutaneous tumors with a significant population of signet-ring cells were studied by immunohistochemistry and electron microscopy. RESULTS: Signet-ring cells were found in a variety of cutaneous neoplasms, including primary cutaneous squamous and basal cell carcinoma and melanoma, as well as in metastatic adenocarcinoma. In all but the metastatic adenocarcinomas the vacuoles were periodic acid Schiff (PAS), PAS-digest, and colloidal iron negative. There was no staining of the vacuoles with antibodies against keratins and vimentin. Electron microscopy showed only empty spaces in all cases. CONCLUSION: The signet-ring like appearance of the cells in most of these conditions is probably the result of coalescence of intracytoplasmic vacuoles and not accumulation of secretory products. Signet-ring formation is not specific for cellular lineage but can occur in a variety of cutaneous neoplasms, analogous to other cellular alterations as rhabdoid, granular, clear, spindle, and balloon cells and oncocytes.  相似文献   
104.
Intrinsic or acquired drug resistance is a major limiting factor of the effectiveness of chemotherapy. Increased expression of either the MRP gene or the MDR1 gene has been demonstrated to confer drug resistance in vitro. In this study, we examined MRP and MDR1 gene expression in a panel of 17 small cell lung cancers (SCLC) xenografted into nude mice from treated and untreated patients using an RT-PCR technique. For some of them, the outcome of the corresponding patients was known and we related MDR1/MRP expression with the xenograft response to C′CAV (cyclophosphamide, cisplatin, adriamycin and etoposide) combined chemotherapy. Fifteen (88%) of the 17 cases of SCLC were found to be positive for either MDR1 or MRP. MRP gene expression was present in 12 (71%) of 17 cases, whereas MDR1 gene expression was detected in eight (50%) of 16 cases. For six SCLC, the survival duration of patients differed, with three patients surviving for more than 30 months after therapy. Among these six tumours, five expressed MRP and/or MDR1. These six xenografts responded to the C′CAV treatment but a significant rate of cure was obtained in only three cases. No obvious relationship was observed between the response to this treatment and MRP or MDR1 expression. However, the remarkably high levels and frequency of MRP expression in some SCLC samples indicate that future developments in chemotherapy of this tumour type should anticipate that drugs which are substrates of MRP may be of limited effectiveness.  相似文献   
105.
Laser thermokeratoplasty (LTK) can be applied for correction of hyperopia and astigmatism by means of concentrically placed coagulations. Because of the temperature rise during coagulation, damage of the endothelial cells directly below the irradiated areas is possible. In this study, we examined the extent of the thermally denatured zones for different laser parameters and the threshold of thermal endothelial damage as a function of of temperature and duration of elevated temperatures. The threshold for thermal damage of endothelial cells was determined in isotonic NaCl solution for temperature exposures of 10 s and 1 min in a water bath. To determine the damage zones, corneas were irradiated under standardized conditions with a continuously emitting infrared (cw-IR) laser diode at various wavelengths and different power values and were stained after preparation with trypan blue and alizarine red. The extensions of the damage zones were compared with calculated isotherms. Fifty percent cell damage was found at temperatures of 65 °C for heating times of 10 s and at 59 °C for 1 min. With thicker corneas, less laser power and higher absorption coefficients, the damage zone was reduced. The damage range determined corresponded to the calculated isotherms of 60 °C and 70 °C. Regarding clinical LTK, a loss of endothelial cells can be predicted and minimized or totally avoided by choosing the appropriate irradiation parameters.  相似文献   
106.
Trauma und Berufskrankheit - Zusammenfassung Die minimalinvasive Osteosynthese (MIO) des Pilon tibiale beschreibt 3 unterschiedliche Behandlungskonzepte: 1. Die alleinige Behandlung mit einem...  相似文献   
107.
Genomic approaches to skin cancer diagnosis.   总被引:2,自引:0,他引:2  
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108.
109.
The aim of this study is to determine the S100B concentration in colostrums of 51 Burkinabe and 30 Sicilian women, still living in their countries, and in case of a difference to search for its explanations, considering also ethnic differences. The concentration of S100B, in colostrums of the first three days from the delivery, was assessed with commercial immunoluminometric assay. The production of colostrums was significantly higher in Burkinabe women, where the colostrums S100B levels in the first day of lactation showed to be at 24 h higher than those of Sicilian mothers (672.21 ± 256.67 ng/ml vs 309.36 ± 65.28 ng/ml) and progressively decreased reaching the values of Sicilian mothers in the second and third day (204.31 ± 63.25 ng/ml and 199.42 ± 45.28 ng/ml, respectively). Correlation was found between the level of S100B and the length of stage II (duration of expulsive phase of delivery), but the correlation with pain was found only in Burkinabe women. The S100B level in colostrums of Burkinabe mothers differs from that of Sicilians only in the first day of lactation, and in consideration that Burkinabe women produce more colostrums, their newborns receive, during the first days of life, an higher amount of S100B. The elevated quantity of S100B ingested by Burkinabe newborn in the first days of life could promote the physiological postnatal brain adaptation and maturation in the precarious delivery condition of African infants.  相似文献   
110.
Adult T-cell leukaemia lymphoma in an Aborigine   总被引:1,自引:0,他引:1  
Abstract A 44-year-old Aborigine with Adult T-cell Leukaemia/Lymphoma (ATLL) due to HTLV-I is reported. He presented with transverse myelitis of subacute onset, and subsequently developed frank T-cell leukaemia complicated by splenomegaly and hypercalcaemia. Cell surface marker studies showed a phenotype of CD3 + CD4 + CD8-CD25 +, and serological and molecular studies confirmed HTLV-I infection. This is the first report of ATLL in an Australian Aborigine.  相似文献   
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