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971.
R D Errington D Ashby S M Gore K R Abrams S Myint D E Bonnett S W Blake T E Saxton 《BMJ (Clinical research ed.)》1991,302(6784):1045-1051
OBJECTIVE--To compare high energy fast neutron treatment with conventional megavoltage x ray treatment in the management of locally advanced pelvic carcinomas (of the cervix, bladder, prostate, and rectum). DESIGN--Randomised study from February 1986; randomisation to neutron treatment or photon treatment was unstratified and in the ratio of 3 to 1 until January 1988, when randomisation was in the ratio 1 to 1 and stratified by site of tumour. SETTING--Mersey regional radiotherapy centre at Clatterbridge Hospital, Wirral. PATIENTS--151 patients with locally advanced, non-metastatic pelvic cancer (27 cervical, 69 of the bladder, seven prostatic, and 48 of the rectum). INTERVENTION--Randomisation to neutron treatment was stopped in February 1990. MAIN OUTCOME MEASURES--Patient survival and causes of death in relation to the development of metastatic disease and treatment related morbidity. RESULTS--In the first phase of the trial 42 patients were randomised to neutron treatment and 14 to photon treatment, and in the second phase 48 to neutron treatment and 47 to photon treatment. The relative risk of mortality for photons compared with neutrons was 0.66 (95% confidence interval 0.40 to 1.10) after adjustment for site of tumour and other important prognostic factors. Short term and long term complications were similar in both groups. CONCLUSIONS--The trial was stopped because of the increased mortality in patients with cancer of the cervix, bladder, or rectum treated with neutrons. 相似文献
972.
J.K. Macleod I. Howe J. Cable J.D. Blake J.T. Baker D. Smith 《Journal of insect physiology》1975,21(6):1219-1224
The major volatile chemical constituents present in the scent glands of the bronze orange bug (Musgraevia sulciventris) and the larger horned citrus bug (Biprorulus bibax) have been identified by gas chromatography and mass spectrometry. The amount of trans-2-octenyl acetate present in M. sulciventris showed considerable seasonal variation but no evidence was found to support the postulated rôle of this compound as a sex pheromone in these insects. 相似文献
973.
R L Kirk E M McDermid N M Blake D C Gajdusek W C Leyshon R MacLennan 《American journal of physical anthropology》1974,41(2):301-316
Red cell samples from persons belonging to four Amerindian linguistic groups in Colombia were investigated for genetic variants in eight blood group systems: for three of the groups investigations were extended to ten red cell enzyme and four serum protein systems. The groups studied are the Noanama (including six Empera) of the Rio Siquirisua and Rio Docampado on the Pacific lowlands and the Cofan, Ingano and Siona Indians of the Upper Rio Putumayo and its tributaries to the east of the Andes. Only blood group O was present among two of the groups and the same groups were 100% Kp(b +), k in the Kell system. Di(a +) frequencies were high in three groups and there was marked variation between groups for the MNS, Rh, P, Lewis and Duffy systems. Polymorphism in all the three linguistic groups studied for serum proteins and red cell enzymes was present only in the red cell acid phosphatase, phosphoglucomutase (locus-1) and haptoglobin systems. 6-phosphogluconate dehydrogenase was polymorphic in the Noanama, and caeruloplasmin was polymorphic in the Ingano linguistic group. In addition two persons belonging to the Cofan linguistic group revealed the presence of an “atypical” component in the lactate dehydrogenase system. No variation was found in the other six red cell enzyme and two serum protein systems. Comparison with published data on red cell enzyme and serum protein groups for other South American Amerindian populations shows the Colombian populations studied here most closely resemble the Cayapo of Brazil. 相似文献
974.
L P Allen A M Blake G M Durbin D Ingram E O Reynolds P D Wimberley 《BMJ (Clinical research ed.)》1975,4(5989):137-139
During a nine-month period 24 newborn infants were treated with continuous positive airway pressure (CPAP) or mechanical ventilation delivered through a facemask. The mask was held in place in a way that minimised trauma and distortion of the head. The median birth weight of the infants was 1096 g and their median gestational age 29 weeks.The usual reason for treatment was hyaline membrane disease or recurrent apnoea due to inadequate control of breathing. Twenty-one of the infants survived. The technique was simple to apply and complications were minimal. We suggest that it may have advantages over other methods of applying CPAP or mechanical ventilation to infants mildly affected by respiratory illnesses and that it should be useful in avoiding endotracheal intubation or reducing the length of time that infants with more serious illnesses are intubated. 相似文献
975.
976.
R. L. Kirk E. M. McDermid N. M. Blake R. L. Wight E. H. Yap M. J. Simons 《Human genetics》1973,17(4):345-350
Summary Blood samples from a series of Dani speaking persons from Pit River, West Irian have been studied for genetic variants in 14 red cell enzyme and 5 serum protein systems. Four of the red cell enzyme systems were polymorphic: acid phosphatase, 6 phosphogluconate dehydrogenase, adenosine deaminase and phosphoglucomutase (locus 1). Two of the serum protein systems, haptoglobin and transferrin, were polymorphic. In the other systems three MDH New Guinea-1 variants were detected and two persons with variants, one MS and one SS, in the protease inhibitor system were detected also. An unusual variant in the PGM (locus 2) system has not yet been adequately identified. All other systems were monomorphic.
Zusammenfassung Blutproben einer Anzahl Dani-sprechender Personen des Pit River-Gebietes in West-Irian wurden auf genetische Varianten in 14 Erythrocytenenzym- und 5 Serumprotein-Systemen untersucht. 4 der Erythrocytenenzym-Systeme waren polymorph: Saure Phosphatase, 6PGD, Adenosindeaminase und Phospho-glucomutase1. Zwei der Serum-protein-Systeme, Haptoglobin und Transferrin, waren polymorph. In den anderen Systemen wurden 3 MDH New Guinea-1-Varianten gefunden, ebenso wie 2 Personen mit Varianten, 1 MS und 1 SS, im Pi-System. Eine ungewöhnliche Variante im PGM2-System ist noch nicht ausreichend bestimmt worden. Alle anderen Systeme waren monomorph.相似文献
977.
Polynucleotides. XI. Thermodynamics of (A) N -2(U) infinity from the dependence of T m N on oligomer length 总被引:3,自引:0,他引:3
The variation in the helix-coil transition temperature, TmN, with oligomer length, N, for the system ((I)) has been examined. The results for N = 4-13, measured in 0.2M Na+, have been analyzed in terms of the expression of Blake (1972): ((II)) where cm is the free oligomer concentration at TmN, and Vrf is the thermodynamic free volume available to a helical base-triplet residue. The correlation coefficient for the fit to expression (II) of data obtained over a 50° temperature range is 0.997 when ΔHr = ?12.6 kcal/mole of base-triplets (independent of oligomer length (N ? 4) or temperature), the value previously obtained from both calorimetry of (A)∞·2(U)∞ and (A)4 concentration dependence of Tm. It is found that Vrf = 8.0 × 10?4 1/mole (± 30%) or 1.33 Å3 per helical base-triplet, and is constant with temperature. A maximum value for Vrf of 21.0 × 10?4 1/M (± 1.3%), equivalent to 3.54 Å3 per helical basetriplet is obtained by the same treatment of the helix-coil transition data for the three-stranded helix formed by adenosine (N = 1) and 2(U)∞ obtained by Davies and Davidson (1971). 相似文献
978.
Oestrogen and nuclear binding sites. Determination of specific sites by [3H]oestradiol exchange 总被引:7,自引:0,他引:7
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A method was developed for the determination of the number of specific oestradiol-binding sites in the nuclear fraction of oestrogen-sensitive tissues. The method is based on the exchange of [(3)H]oestradiol with non-labelled oestradiol that is bound to nuclear binding sites. The number of specific nuclear binding sites after the injection of 2.5mug of oestradiol, an amount sufficient to saturate all binding sites, is 1.6-1.7pmol per immature uterus. The number of sites occupied after an injection of physiological amounts of oestradiol (0.1mug) was 0.46pmol. The injection of oestradiol results in an increased number of nuclear binding sites in uterus and vagina, but has no effect on kidney or muscle. Injections of testosterone or progesterone failed to increase the number of uterine nuclear binding sites. This method permits an evaluation of the number of oestradiol-binding sites in the nuclear fraction of various tissues as a function of either endogenous oestradiol or non-labelled oestradiol administered by injection. 相似文献
979.
Dinitrophenol-stimulated adenosine triphosphatase activity in extracts of Desulfovibrio gigas 总被引:5,自引:3,他引:2
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A dinitrophenol (DNP)-stimulated adenosine triphosphatase (ATPase) has been found in both the soluble and particulate fractions of the anaerobic sulfate-reducing bacterium, Desulfovibrio gigas. As the soluble ATPase was labile to storage, only the particulate enzyme was studied in detail. It was optimally stimulated by DNP at 4 mm, and activity was insensitive to inhibition by ouabain. The ATPase was stimulated by both Ca(2+) and Mg(2+), but the magnitude of the stimulation was dependent upon pH. In the presence of Ca(2+) the optimum pH was 6.5, whereas, in the presence of Mg(2+) the pH optimum was 8.0. However, under optimal conditions the activity was the same with either Mg(2+) or Ca(2+). Both adenosine triphosphate and guanosine triphosphate were hydrolyzed, but activity toward guanosine triphosphate was only one-tenth that observed with adenosine triphosphate. 相似文献
980.
Neisseria gonorrhoeae that resist complement-dependent killing by normal human serum (NHS) are sometimes killed by immune convalescent sera from patients recovering from disseminated gonococcal infection (DGI). In these studies, killing by immune serum was prevented or blocked by immunoglobulin G (IgG) or F(ab)2 isolated from NHS. Purified human IgG antibodies directed against gonococcal protein III, contained most of the blocking activity in IgG. In addition, immune convalescent DGI serum, which did not exhibit bactericidal activity, was restored to killing by selective immunodepletion of protein III antibodies. Blocking IgG or F(ab)2 prepared from IgG, partially inhibited binding of bactericidal antibody to N. gonorrhoeae. Also, binding of a monoclonal antibody recognizing N. gonorrhoeae outer membrane protein PIII was almost completely inhibited by blocking F(ab)2.Presensitization of N. gonorrhoeae with increasing concentrations of blocking IgG or F(ab)2 before incubation with bactericidal antibody and an antibody free source of complement, increased consumption and deposition of the third component of human complement (C3) and the ninth component of complement (C9) but inhibited killing in dose-related fashion. 相似文献