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Paul Weiss

knowledge of this intricate interdependence grows, the more judiciously shall we be able to deal with the practical problems of nerve repair. For example, certain measures that might be devised to stimulate the growth rate of nerve fibers might turn out to promote even more an obstructive fibrosis so that the net effect on nerve restitution would be adverse. Or one might try to amplify an undersized nerve source by causing the fibers to branch profusely during regeneration, 18, 39 only to find out eventually perhaps that the number of branches any one neuron can maintain

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C. F. List, J. R. Williams and G. W. Balyeat

amazed to find the entire tumor mass hemorrhagic, even though the area of surgical interference was very limited. It is not clear what causes a spontaneous vascular accident in a pituitary adenoma but there is reason to believe that the growth rate of neoplastic cells may outstrip their blood supply and that increased intracapsular pressure favors ischemia and thrombosis. Once infarction has occurred, a large portion of the adenoma,, or even the entire tumor, becomes a hemorrhagic mass that swells up as rapidly as a soaked sponge. Such sudden increase of volume and of

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F. A. Martin, J. E. Webster and E. S. Gurdjian

13 Masses of the midline base  Neoplasms 18 12 0 1 0 3 2 Masses of the posterior fossa  Neoplasms 30 8 5 0 2 0 15 Accurate localization was made most often in cases of rapidly growing gliomas and the malignant meningiomas over the convexities. These were localized in 66 per cent of the cases. The growth rate of the mass appeared to influence the frequency of appearance of discrete foci. The slower-growing gliomas of the hemispheres were localized in 62 per cent of the cases. The

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William F. Collins, James L. O'Leary, William E. Hunt and Henry G. Schwartz

distance of 46 mm. Erlanger and Schoepfle 3 used as much as 160 mm. conduction distance. From our results we would believe that for the conduction distances and regeneration intervals given in the Berry, Grundfest and Hinsey 1 experiments the fibers might have reached a relatively uniform velocity, and a later article by Berry and Hinsey 2 states that at greater conduction distances the conduction velocity is lower. Thus tapering (Young 8 ) receives significant support. We did not make a systematic effort to determine the maximum growth rate of regenerating fibers

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Harvey Gass

patient who had had a cystic astrocytoma treated three years earlier by injection of radioactive gold into the cystic space was seen now having recurrent symptoms. This form of treatment had been utilized in 50 patients without any final conclusions having yet been drawn. Another form of treatment being explored by Dr. Orloff was ligation of the common carotid artery for inoperable and basal brain tumors. She felt that by limiting the blood supply to the tumor this way plus the effect of some reflex action from handling the carotid body, reduction of the growth rate of

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Richard Jelsma and Paul C. Bucy

therapy retards the growth of some tumors but for periods of less than a year. By the end of 18 months the natural growth rate of the tumor again is the determining factor in survival. Or, it is possible that radiation therapy is not as effective against the slower growing tumors. This finding that radiation therapy does not affect the length of survival after 18 months contrasts with the fact that surgery does. As mentioned before, only patients having large resections lived for more than 1 year. This difference may be because surgery does more than retard tumor growth

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Donald P. Becker and Frank E. Nulsen

placement. By contrast, a catheter correctly placed at age 3 months or older is “safe” for at least 6 months, when a chest x-ray allows better prediction of its rate of ascent in a given patient. Catheters in correct position at age 1 year require only yearly x-ray checks until a near critical level is reached. Catheters still as low as T-6 after 3 years of age may remain patent indefinitely, or at least until growth rate is accelerated in adolescence. TABLE 3 Elective revision: time required for catheter migration from T6–7 to T-4 correlated with age of patient

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D. P. McNeel and M. E. Leavens

alive at 6 and 14 years. 3 We did not encounter in the literature any reported cases of long-term survival with multiple craniotomies for recurrent metastatic malignant melanoma. A number of factors make the evaluation of this single case difficult. The natural course of malignant melanoma is variable and unpredictable from patient to patient. The tumor may show varying growth rates at different times in the same individual. 6 The patient may be asymptomatic for years; then, with recurrence, death may ensue in a few months. This case is presented to illustrate

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Donald D. Matson and John F. Crigler Jr.

hypothalamus is presented to emphasize the importance of including measurements of these hormonal activities when carrying out a complete neurological examination. TABLE 4 Neuroendocrine dysfunction in children, clinical and laboratory evaluation Signs and Symptoms Altered growth rates (heights, weights) Altered maturation (skeletal, sexual) Polydypsia and polyuria Fever, labile temperature responses Behavioral changes Laboratory Evaluation of Hormonal Regulation ADH—fluid balance, serum electrolytes or osmolalities

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Hilel Nathan and Mordechai Feuerstein

observations, the angulation reached 45°. An irregularity in the growth rate of the dural sac during fetal life could condition the angulated course of the nerves. It is well known that until the third month the spinal cord fills the entire length of the spinal canal, and the spinal nerves pass horizontally from their origin straight through the dural sac to their corresponding intervertebral foraminae. From the fourth month of embryonic life, the vertebral column grows and elongates at a faster rate than the spinal cord. Since the cord is anchored above to the endocranial