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71.
Developmental regulation of annexin II (Lipocortin 2) in human brain and expression in high grade glioma. 总被引:7,自引:0,他引:7
In experiments to identify molecules that might be important in the pathogenesis of glioblastoma multiforme, the most common malignant brain tumor, we found that annexin II (Lipocortin 2, p36), a likely second messenger in several different mitogenic pathways, was highly expressed in tumor tissue of glioblastoma multiforme (9 of 9) and highly anaplastic astrocytoma (2 of 6), but not in astrocytomas of lower pathological grade (0 of 6). We also detected high levels of annexin II expression in fetal brain during the period when radial glia proliferate, although annexin II expression was not detected in normal adult brain. These data demonstrate that annexin II expression is developmentally regulated in the human central nervous system and suggest that the early progenitor radial glia share important characteristics with highly malignant glial tumors. 相似文献
72.
Implications of admission hypothermia in trauma patients 总被引:2,自引:0,他引:2
Hypothermia is common after severe injury, and has been associated with an increased mortality rate in patients stratified by anatomic indices of injury severity. In this retrospective study of 173 patients, early post-traumatic hypothermia was found to correlate with physiologic indicators of volume deficit, independently of the amount of intravenous fluid received. There was no correlation found between admission core temperature and time from injury, blood alcohol, or presence of severe closed head injury. Hypothermic patients (less than 35 degrees C) had a lower predicted probability of survival and a higher mortality rate than euthermic patients (greater than or equal to 35 degrees C). However, when patients were stratified by physiologic and anatomic indicators of injury severity, mortality rates among the euthermic and hypothermic patients were not significantly different. Early post-traumatic hypothermia does not appear to exert an independent effect upon outcome. 相似文献
73.
Paramyosin is the Schistosoma mansoni (Trematoda) homologue of antigen B from Taenia solium (Cestoda) 总被引:9,自引:0,他引:9
J P Laclette A Landa L Arcos K Willms A E Davis C B Shoemaker 《Molecular and biochemical parasitology》1991,44(2):287-295
Antigen B, a major antigen of the cestode parasite Taenia solium, has been purified and a portion of amino acid sequence obtained. Paramyosin of the trematode parasite Schistosoma mansoni, an immunogenic protein that has shown promise as a vaccine candidate, has several biochemical and immunological properties in common with antigen B. A full-length cDNA clone of S. mansoni paramyosin has been obtained and the predicted translation product contains a sequence that is highly homologous to the sequence obtained for antigen B. The predicted amino acid composition and isolectric point of paramyosin are nearly identical to those established for antigen B. Recombinant S. mansoni paramyosin, expressed in Escherichia coli as a fusion protein with beta-galactosidase, was recognized by antisera against T. solium antigen B. We conclude from these results that S. mansoni paramyosin and T. solium antigen B are homologous proteins. Since S. mansoni paramyosin is thought to be a muscle protein and T. solium antigen B a secreted glycoprotein with anti-complement activity, this conclusion raises some interesting questions regarding the role of this class of proteins in the host-parasite relationship. 相似文献
74.
75.
An outbreak of cyptosporidiosis occurred in late April 1993 among resort hotel guests which was temporally associated with, but geographically distant from, a massive waterborne outbreak of cryptosporidiosis in Milwaukee, Wisconsin, that occurred in late March and early April of 1993. A case-control study was performed among groups with members who reported illness and among a systemic sample of groups who stayed at the resort hotel during the risk period. Of 120 persons interviewed, 51 (43%) met the case definition. Swimming in the resort hotel''s pool was significantly associated with case status (OR = 9.8; 95% Cl 3.4, 29.7), as was consumption of ice from the hotel''s ice machines (OR = 2.3; 95% Cl 1.01, 5.2). When analysis was restricted only to laboratory-confirmed cases and controls, swimming pool use was the only risk factor significantly associated with illness (OR = 13.0; 95% Cl 2.6, 88.7). Following waterborne outbreaks of cryptosporidiosis associated with water supplies, swimming pools should be considered as possible ongoing sources for transmission regionally. 相似文献
76.
Gastric cancer is unusual during pregnancy. Also, because of the physiologic changes that occur with pregnancy, it is rare to see a worsening of peptic ulcers during pregnancy. A patient with an exacerbation of peptic ulcers presented with gastric carcinoma during pregnancy. 相似文献
77.
Rats were implanted with bilateral cannulas in an area just medial to the ventral nucleus of the lateral lemniscus, an obligatory relay along the acoustic startle pathway. Bilateral infusions of excitatory amino acid transmitter antagonists into this region (10, 25 or 50 nmol per side) produced a rapid, dose-dependent depression of acoustic startle. gamma-D-Glutamylglycine, gamma-D-glutamylaminomethyl sulfonate and 2-amino-5-phosphonovalerate were equally effective in depressing the startle response over this dose range. These results indicate that excitatory amino acid transmitters play an important role in the expression of acoustic startle at this part of the startle pathway. 相似文献
78.
Stromal keratitis and iritis developed in the left eye of a healthy 45-year-old man with no history of ocular disease, trauma, or contact lens wear. The clinical course over a 2-year period was characterized by progressive central disciform keratitis, recurrent anterior stromal patchy infiltration, and iritis which was partially controlled with topical corticosteroids and broad-spectrum antibiotics. Results of bacterial, viral, fungal, and chlamydial cultures were negative. Results of histopathologic examination of a corneal biopsy specimen and, later, a penetrating keratoplasty specimen showed many extracellular and intracellular spores in degenerating keratocytes. By electron microscopy there were encapsulated oval structures measuring approximately 3.5 to 4 microns in length x 1.5 microns in width. Mature spores had well-developed cell walls that contained two abutted nuclei (diplokaryon) and a redundant polar tubule with six coils. These structures are characteristic of a protozoa in the genus Nosema. 相似文献
79.
V Raptopoulos A Davidoff A Karellas M A Davis B L Coolbaugh E H Smith 《AJR. American journal of roentgenology》1988,150(6):1303-1306
Visualization of the head of the pancreas by CT was prospectively evaluated in two groups of 100 patients who did not have pancreatic disease. Patients were given either a fat-density oral contrast material (12.5% corn-oil emulsion and metoclopramide) or a conventional high-density oral contrast material (barium suspension or iodinated solution). There was no statistically significant difference in the subjects' tolerance to the two regimens. There was, however, a significant improvement in ability to distinguish the head of the pancreas from the duodenal C-loop when the fat-density contrast material was given. When pancreaticoduodenal discrimination was graded, patients given corn-oil emulsion and metoclopramide received an average score of 0.94, whereas those given the high-density agent received an average score of 0.74, with 1.00 being the highest possible score (p less than .005). These data suggest that for routine CT evaluation of the head of the pancreas, a combination of corn-oil emulsion and metoclopramide may be superior to the conventional high-density oral contrast agents given without metoclopramide. 相似文献
80.
Numerous investigators have reported the safety, cost effectiveness, and low morbidity and mortality of percutaneous endoscopic gastrostomy (PEG) but not studies compare the results of gastroenterologists and surgeons performing PEG. In a retrospective review of PEG performed at our institution, morbidity and mortality were compared between these two groups. The procedure was performed by either the surgical service (n = 49) or gastroenterology service (n = 51). One hundred PEGs were successfully placed in 92 patients. Three placement failures occurred in the gastroenterology group. Major complications were defined as conditions requiring operative intervention or resulting in death. Minor complications, using a defined list (13 different complications), were those not serious or life-threatening, which were managed medically or resolved without treatment. Twenty-nine minor (17 patients) complications and 3 major (3 patients) complications occurred in the gastroenterology group. Thirteen minor (11 patients) complications and 4 major (4 patients) complications occurred in the surgery group. Overall 30-day mortality was 14 per cent (13 patients), two of which were probably procedure-related in the gastroenterology group. In both groups, there was no difference in the numbers of patients who had complications (P greater than 0.05). The complication rate (numbers of complications/number of patients) doubled in the gastroenterology group compared with the surgery group for minor (P less than 0.04) and total complications (minor and major--P less than 0.06). Since PEG is a procedure frequently performed by gastroenterologists, it is imperative that surgeons, particularly those not performing endoscopy, be aware of the potential morbidity associated with PEG. 相似文献