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71.
Phase I studies were conducted in 58 adult cancer patients with Baker's Antifol (BAF), a new active-site directed inhibitor of dihydrofolate reductase. Dose escalation ranged from 10 to 250 mg/m2/day X 5 days and courses of treatment were repeated every 2-3 weeks. Biologic effects were observed mostly at doses greater than 100 mg/m2/day X 5 days. The patients developed myelosuppression during 19% of the trials. Other types of toxicity were dermatitis in 12 to 30% and stomatitis in 7 to 38% of the trials. Toxicity was directly related to the impairment of the patient's liver function. Two partial responses (in a patient with adenocarcinoma of the lung and a patient with transitional cell carcinoma of the bladder) occurred. BAF is an active new chemotherapeutic agent which deserves further clinical trials in patients with various malignancies.  相似文献   
72.
The usability of the constructive neural algorithms as pattern classifiers is investigated. It is pointed out that the unboundedness of the decision regions formed by most neural recognizers leads to substantial limitations of the generalization capabilities of these nets. We specify a constructive neural recognizer that forms bounded decision regions, and report the results of this algorithm on a series of benchmark problems that resemble the usual pattern recognition problems.  相似文献   
73.
A stable standard suspension for red-cell counts   总被引:3,自引:0,他引:3  
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74.
A significant correlation found in a pilot study between heart rate and digit Symbol performance was utilized to investigate effects of type of arousal induction on performance. 60 Ss were arranged in a 3 X 2 factorial design, divided into high and low drive via heart rate. Ss first performed on a Digit Symbol task; followed by a frustrating experience, physical exertion, or nonfrustrating task; followed by readministration of an alternate form of the 1st Digit Symbol problem. The results showed that the relation between activation and performance, in most instances followed the hypothetical inverted U function. (17 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
75.
The availability of a number of new immunosuppressive drugs has resulted in significant improvements in the outcome of kidney transplantation. Currently 1-year graft survival rate for cadaver kidney transplants is approximately 85%. A number of new agents are presently in clinical studies. This article reviews the currently available agents and examines various aspects of induction and maintenance immunosuppressive therapy, and the treatment of acute rejection episodes. In addition, the agents currently in clinical trials and future directions in immunosuppressive therapy are discussed.  相似文献   
76.
77.
Multistage induction mass accelerator   总被引:1,自引:0,他引:1  
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78.
79.
We have previously presented a rapid, high yield method for the large scale purification of homogeneous RNA polymerase II from wheat germ (Jendrisak, J.J., and Burgess, R.R.(1975), Biochemistry 14, 4639), and we now report a detailed study of its subunit structure. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate indicates that polypeptides with molecular weights of 220 000, 140 000, 40 000, 27 000, 25 000, 21 000, 20 000, 17 800, 17 000, 16 500, 16 000, and approximately 14 000 are associated with the enzyme. Two-dimensional polyacrylamide gel electrophoresis, by which the subunits were separated in the first dimension in the presence of 8 M urea at pH 8.7 and in the second dimension in the presence of 0.1% sodium dodecyl sulfate, indicates that the 40 000 molecular weight component is composed of two nearly identical polypeptides and that the low molecular weight components (smaller than or equal to 40 000) are acidic proteins except for the 25 000 molecular weight polypeptide.  相似文献   
80.
In a recent study, J. Tedeschi and T. Levy (see record 1971-28825-001) related responsiveness to social reinforcement in chance vs. skill tasks to previous findings of external control in lower-class blacks and internal control in middle-class whites. In the present article, P. Burgess examines the rationale behind Tedeschi and Levy's predictions, questions the validity of their experimental paradigm, and suggests that their results do not provide adequate support for their conclusions. In a separate article, Tedeschi & Levy reply to Burgess's criticisms. (22 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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