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991.
The structure-activity relationship between (E)-5-(2-bromovinyl)- and 5-vinyl-1-beta-D-arabinofuranosyluracil (BV-araU and V-araU) in inhibition of Epstein-Barr virus (EBV) was evaluated. Both V-araU and BV-araU effectively inhibited EBV replication in virus-producer P3HR-1(LS) cells, as determined by DNA-DNA hybridization. The 50% effective doses (ED50) for viral DNA replication were 0.005 and 0.3 microM for V-araU and BV-araU, respectively. The in vitro therapeutic index was 4000 for V-araU and 1300 for BV-araU. Synthesis of EBV-induced polypeptides with molecular weights of 145,000 (145, 140, 130, and 110 kDa) was significantly inhibited by both drugs. Only V-araU inhibited the synthesis of 85-, 55-, and 32-kDa polypeptides by approx. 50%. Kinetic analysis of inhibition and reversibility of EBV DNA replication after removal of the drugs indicated that BV-araU has a more prolonged inhibitory effect than V-araU. These results indicate that the substitution of H by Br in the 5-vinyl group results in marked reduction in anti-EBV activity while prolonging the drug effect and diminishing cytotoxicity.  相似文献   
992.
Genital papilloma virus infection (GPVI) is in many patients a longlasting, relapsing disease for which no effective treatment is available. This fact and the association between the virus and cancer puts much stress on the afflicted patient. Of 41 men with GPVI interviewed, 17 (40%) reported a negative effect of the disease on their sexual life. Most distressing was the fear of transmitting the disease to their partner. After 18 months, 15 (37%) of the 41 men still exhibited signs of GPVI. In the care of patients with GPVI, more attention needs to be paid to the psychosexual effects of the disease.  相似文献   
993.
Results reported are for single dose exposures and refer to 60Co-gamma-irradiation. The RBE determined by V79 cell survival and based on the Do ratio was found to be 1.70 +/- 0.4 ranging from 1.5 to 1.8. In the case of the regeneration of mouse jejunal crypts the RBE was calculated at ten cell survival and was found to be 1.68. The maximum acute mouse skin reaction at a skin score of 2.0 was found to be 2.1 while the average skin reaction was 1.7. Growth retardation of Vicia faba bean roots measured at the level of 50% indicated an average RBE of 3.0 and a range of 2.7 to 3.7. The OER obtained for V79 cell survival was found to be 1.7 to 1.8. Comparison is made with the RBE and OER measurements for the neutron facilities at Clatterbridge, Fermilab and Louvain-la-Neuve which produce neutrons by the same nuclear reaction and whose physical specifications closely resemble those of the Faure neutrons. This comparison indicates that the Faure beam shows no unusual biological features and that its biological effectiveness is in line with that expected from its physical characteristics.  相似文献   
994.
The tick species commonly collected at the Northeast of Spain are reported in this paper. Data on hosts, temperature and humidity requirements, vegetation relationships, altitudinal distribution, and seasonal activity are included. R. sanguineus is commonly collected in areas with Mediterranean vegetation, esteppe, and semi-desertic esteppe, ranging from 190 to 1,000 meters above the sea level. R. sanguineus is related with sparse vegetal areas, and it is absent from areas with dense shrub or forests of every kind; sometimes, small populations may be collected in ecotones between Pinus spp. and esteppe formations. R. pusillus is closely related to areas of Mesomediterranean vegetation, sometimes subordinate to Pinus spp. and Quercus spp. The climate to which the species ally is always of continental type, with a hot and dry summer, and cold winter; although the species is commonly restricted to its main host, Oryctolagus cuniculus, several specimens have been collected from V. vulpes. Our data display the clear affinity of I. ricinus to the Supramediterranean vegetation (Aceri-Quercion faginae), places of Quercetum-Buxetum, as well as the Iberian Oromediterranean vegetation (Pinus sylvestris-Buxus sempervirens). Captures are scarce in forest of Fagus sylvatica, but data suggest that the species may be locally common on such places. Climate for the zones of collection of I. ricinus is Atlantic attenuated, with mild summers and humid winters. D. marginatus is strongly related to the xerophilic vegetation, widely spread through the Mediterranean, Supramediterranean, and hill levels, but does not colonize the true Oromediterranean vegetation. In our captures, the species is commonly collected in pubescent oak formations, but it does not penetrate in true forest associations.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
995.
Placental abruption resulting in fetal death may seriously affect maternal health, especially when clotting disorders arise. The prevailing view is that the clotting system will only normalize after the uterus has been evacuated and therefore prompt delivery, often by induction of labor, is advocated. Over a 3-year period, 16 cases (0.35%) of intra-uterine fetal death due to placental abruption occurred at Leiden University Hospital. Five cases were complicated by severe clotting disorders. All women delivered vaginally. No maternal deaths occurred. In contrast to most authors, we present data showing that in four out of five cases the clotting system started to normalize before the uterus was emptied. We suggest that an expectant approach until recovery of the coagulopathy is safer than aiming at a quick delivery. After stabilization of the clotting disorder, one may then consider evacuation of the uterus, if need be by induction of labor.  相似文献   
996.
The results of treatment of echinococcosis of the left hepatic lobe in 15 patients have been analysed. Resection of the left hepatic lobe is considered an operation of choice in presence of a large cyst.  相似文献   
997.
Ascites and plasma concentrations of soluble tumor necrosis factor receptors p55 and p75 were measured in a prospective study in 34 patients (35 occasions of ascites) with hepatic (5 infected and 21 uninfected) and malignancy-related (9) ascites. All patients had high concentrations of both soluble tumor necrosis factor receptors in ascites and plasma; these were about 500 times higher than the corresponding tumor necrosis factor-alpha concentrations. Ascites levels of soluble tumor necrosis factor receptors p55 and soluble tumor necrosis factor receptors p75 were significantly elevated in patients with malignancy-related (p55: 26.0 +/- 8.6 ng/ml; p75: 20.5 +/- 17.4 ng/ml; mean +/- S.D.) and infected ascites (p55: 25.1 +/- 10.9 ng/ml, p75: 22.6 +/- 11.0 ng/ml) compared with patients with uncomplicated hepatic ascites (p55: 10.1 +/- 4.4 ng/ml; p75: 6.0 +/- 2.6 ng/ml). Patients with infected or malignancy-related ascites also showed higher soluble tumor necrosis factor receptor concentrations in plasma than did patients with plain hepatic ascites. Successful antibiotic treatment of peritonitis reduced soluble tumor necrosis factor receptor p55 and p75 ascites levels in three patients from 24.2 +/- 15.2 ng/ml to 10.7 +/- 1.9 ng/ml and from 20.2 +/- 14.4 ng/ml to 7.5 +/- 1.8 ng/ml, respectively. Soluble tumor necrosis factor receptors p55 and p75 at cutoff levels of 16.5 ng/ml and 9.5 ng/ml, respectively, differentiated between infected or malignant and plain hepatic ascites with diagnostic accuracies of 94% and 89%, respectively. They did not differentiate between infected and malignant ascites. The concentrations of soluble tumor necrosis factor receptor p55 were usually higher in ascites than in plasma in all subgroups of patients.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
998.
Chronic pancreatitis was induced in eight piglets by dividing all pancreatic attachments to the duodenum. Five piglets served as controls. The animals which were operated on were autopsied six weeks thereafter. Ductography and microangiography were performed. Histological preparations of pancreatic tissue were made. All of the animals which underwent operation developed histologically verified chronic pancreatitis. Ductography revealed the main ducts and the side branches to be considerably dilated. They also exhibited variations in calibre and sudden obstructions. Two animals had a large non-infected pseudocyst. No communication between the cyst and the main duct could be demonstrated by ductography. No pancreatic calcifications were seen. The vasculature of the ductal plexuses seems to be derived from interlobular arteries. The animals with chronic pancreatitis had marked diminution of the vascular supply of the ducts. The changes in ductal vascularity correlated with the severity of the histological changes to the pancreas and may, thus, in part explain the progress of pancreatitis.  相似文献   
999.
14 patients with radiologically documented vesicorenal reflux (5 bilateral, 7 unilateral, 2 unilateral double-J stents) received intravesical immunotherapy with bacillus Calmette-Guérin (BCG) after treatment of their superficial urothelial tumors. 1 patient with a double-J stent suffered a highly febrile attack following obstruction of the indwelling ureteral catheter. The other patients tolerated 1 or 2 (6 of 14 patients) courses of BCG without an increase in side effects. Topical intravesical therapy with BCG in patients with vesicorenal reflux seems to be indicated in view of the multicentricity of urothelial carcinoma and can be performed without an increased risk of complications.  相似文献   
1000.
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