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51.
Direct condensation of 2-deoxy-D-ribose (1) with mercaptans using the P4O10/H2O/Bu3N reagent in chloroform resulted in coupling at C-3 to give the anomeric mixtures of the corresponding pentopyranoses 2 and pentofuranoses 3. After acetylation with acetic anhydride in dry pyridine of these 3-alkylthio pentofuranoses, coupling with the nucleobases uracil, thymine, and cytosine in accordance with the Friedel-Crafts catalyzed silyl Hilbert-Johnson method yielded the acetylated D-erythro nucleosides 7 as anomeric mixtures, separable only by means of chromatography either before or after deprotection with ammonia. The nucleosides 8a-e were devoid of any activity against HSV-1 and HIV-1. 相似文献
52.
W D Haire R P Lieberman G B Lund J A Edney A Kessinger J O Armitage 《Bone marrow transplantation》1991,7(1):57-59
Thrombosis is common after placement of silicone rubber subclavian vein catheters in patients with malignancy receiving conventional doses of chemotherapy. To determine the incidence of this complication in marrow transplant patients and the effect of different catheter designs on thrombosis rates, patients were randomized to receive either open-ended Hickman catheters or valve-ended Groshong catheters for venous access during the transplantation procedure. A total of 35 catheters were placed, of which 23 were double-lumen (11 Groshong and 12 Hickman) and 12 were single-lumen (six Groshong and six Hickman). Arm venograms were performed on all patients at the time of hematopoietic recovery or occurrence of symptoms of subclavian vein thrombosis. There were 10 cases of total subclavian vein thrombosis (three were symptomatic) and 12 cases of asymptomatic non-occlusive mural thrombi. Only 13 normal veins were found. There was no difference in thrombosis rate between the Hickman and Groshong catheters. Double lumen catheters tended to be more likely to cause total venous occlusion (nine of 23) than single lumen catheters (one of 12) (p = 0.06, Fisher's exact test). We conclude that subclavian vein thrombosis is a common occurrence after placement of silicone rubber catheters for venous access during marrow transplantation. Most cases are asymptomatic. Groshong catheters are just as likely to cause this complication as Hickman catheters. 相似文献
53.
C Pedersen C M Nielsen B F Vestergaard J Gerstoft K Krogsgaard J O Nielsen 《British medical journal》1987,295(6598):567-569
A total of 276 sequential serum samples from 34 men with antibodies to the human immunodeficiency virus (HIV) followed up for two to seven years were analysed for HIV antigen and antibodies to the viral core and envelope proteins. Results were correlated with clinical outcome and CD4 T lymphocyte count. Both antigenaemia and the disappearance of antibodies to the core protein were associated with development of the acquired immune deficiency syndrome (AIDS) or AIDS related complex and depletion of CD4 cells. Thus AIDS or AIDS related complex developed in eight out of 16 patients with antigenaemia compared with one out of 18 patients without antigenaemia. Low counts of CD4 cells (less than 0.5 X 10(9)/l) were found in 14 of the 16 patients with antigenaemia and five of the 18 without antigenaemia. Nine patients seroconverted to HIV during the study; two of these developed antigenaemia 14 and 16 months after the estimated time of seroconversion. These results show that the late stages of HIV infection are characterised by increased production of antigen and a decrease in antibodies directed against the core protein. Antigenaemia indicates a poor prognosis; and as the antigen test is simple to do and interpret, it may therefore be useful for selecting patients for antiviral treatment. 相似文献
54.
Hodgkin's disease of the mediastinum presented as a sternal mass in two young adults. The original biopsy materials were incorrectly interpreted as eosinophilic granuloma of bone (histiocytosis X). A delayed diagnosis (15 months) resulted in the death of one patient, whereas the other patient, whose diagnosis was made in one week, had an excellent response to therapy. 相似文献
55.
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57.
Administration of balanced or BCAA-enriched amino acid solution in septic rats. Effects on protein synthesis in the liver. 下载免费PDF全文
Total hepatic protein synthesis was measured in vivo with a flooding-dose technique, and the production of total secreted proteins, albumin, complement component C3, and seromucoid fraction was measured in perfused livers of septic rats that received one of three different solutions infused intravenously; Group 1 received 16.4% dextrose; Group 2 received Aminosyn (25% BCAA) in 10.6% dextrose, and Group 3 received Freamine HBC (45% BCAA) in 10.6% dextrose. All solutions were isocaloric, and the amino acid solutions were isonitrogenous. The solutions were administered for 18 or 48 hours after the induction of sepsis. There were no significant differences in mortality rates in the three treatment groups. The negative nitrogen balance seen in the dextrose-infused animals was reversed to the same degree by the two different amino acid solutions. There were no significant differences in hepatic protein synthesis rates in vivo between the three groups of rats. Synthesis rates of secreted proteins in perfused liver were similar in the different treatment groups in the 18-hour experiments, whereas in the 48-hour experiments, synthesis rates of total secreted proteins, C3, and the serumucoid fraction were higher in Group 1 than in Groups 2 and 3. The results suggest that administration of an amino acid solution improves nitrogen balance in sepsis, but that this effect is not caused by stimulated hepatic protein synthesis. The nitrogen-sparing effect during sepsis of a branched chain amino acid (BCAA)-enriched solution does not seem to be superior to that of a balanced amino acid solution. 相似文献
58.
S S S?rensen T K Glud P J S?rensen A Amdisen E B Pedersen 《Nephrology, dialysis, transplantation》1990,5(4):247-257
Renal tubular sodium and water handling determined by the lithium clearance technique, plasma concentrations of atrial natriuretic peptide (ANP), angiotensin II, aldosterone, arginine vasopressin (AVP), and urinary excretion of prostaglandin E2 (PGE2) were determined both during basal conditions and before and after intravenous sodium loading with a 2.5% sodium chloride solution in patients with polycystic kidney disease (PKD), ten with normal or slightly reduced kidney function (PKDN) and seven with moderately reduced kidney function (PKDR), and in 15 healthy controls. In PKDN tubular function was normal, whereas in PKDR both proximal and distal reabsorption of sodium and water were reduced. Angiotensin II and aldosterone were normal in both groups of patients. During basal conditions ANP was higher in PKDR than in PKDN. PGE2 was significantly higher in PKDR than in PKDN. For all patients significant correlations were found between GFR and both ANP (rho = -0.51, n = 17, P less than 0.05) and PGE2 (rho = -0.53, n = 17, P less than 0.05). It is concluded that renal sodium handling is normal in the early stages of PKD. With deterioration of kidney function both proximal and distal tubular reabsorption of sodium is reduced and the accompanying changes in ANP and PGE2 may be compensatory phenomena counteracting declining glomerular filtration rate. 相似文献
59.
M B Petersen S A Pedersen G Greisen J F Pedersen L M?lsted-Pedersen 《British medical journal (Clinical research ed.)》1988,296(6622):598-600
Ninety nine consecutive insulin dependent and 101 non-diabetic pregnant women were examined by ultrasonograph to assess early fetal growth. In 42 of the diabetic mothers and three of the non-diabetic mothers the scan showed early intrauterine growth delay. At 4-5 years of age all children available for study were evaluated by the Denver developmental screening test. Only 23 of the 34 children of diabetic mothers with early intrauterine growth delay had normal test scores compared with 46 of the 50 children of diabetic mothers with normal intrauterine growth. The children failed in personal-social development, gross motor development, and particularly in language and speech development. Children of diabetic mothers with normal early fetal growth had scores very similar to those of the children of non-diabetic mothers, of whom 76 of the 86 tested had normal scores. This study suggests that children with a history of growth delay in early diabetic pregnancy should be screened for possible developmental impairment. 相似文献
60.
T. Pedersen J. S. Jensen A. Risbo E. Henriksen 《Acta anaesthesiologica Scandinavica》1988,32(8):681-685
The purpose of this study was to identify factors which will predict the risk of severe postoperative complications in individual patients in a neurosurgical unit. Eleven risk factors were investigated in 363 neurosurgical patients, of whom 40 (11%) developed postoperative complications requiring mechanical ventilation for more than 24 h in an intensive care unit, 16 were found to be severely disabled or in a vegetative state at follow-up 1 month after admission, and 28 patients died. By applying stepwise, logistic regression analysis to the patient's data, we were able to select two significant risk variables, i.e. the Glasgow Coma Scale (GCS) 8 or less preoperatively and emergency anaesthesia. The presence of GCS 8 or less on the consciousness scale was associated with postoperative complications in approximately 40% of the cases. Emergency patients with severe neurological damage had the greatest risk of postoperative complications (93%). Fatal outcome for patients with postoperative complications was seen in 40% of the cases. 相似文献