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In this paper I argue that large defense firms can successfully diversify into civilian markets if innovators gain complementary knowledge and power to promote new civilian innovations. For such firms, diversification is neither easy nor impossible, but requires that new product teams overcome barriers based on bureaucracy, changing managerial regimes, and state policies that discourage diversification. Political barriers to diversification, based on managerial choices and government policies, exist both within and outside the firm. Although specialization hurdles based on knowledge can be overcome, political barriers are more challenging, and limit the rate of civilian spin-offs in large military hub firms.

To determine whether measurement of serotonin in urine would give useful complementary information to the usual measurement of 5-hydroxyindoleacetic acid (5-HIAA) in urine and platelet serotonin in platelets, I measured these analytes in 75 consecutive patients with carcinoid tumors, and found that 75% had above-normal urinary 5-HIAA excretion, 64% had above-normal serotonin excretion, and 64% had above-normal platelet serotonin concentration. Six patients had increased urinary serotonin, but 5-HIAA excretion and platelet serotonin concentration were normal. Only two of a further 50 patients with solid noncarcinoid tumors--and none of 55 patients with flushing or diarrhea, who did not prove to have a carcinoid tumor--had increased urinary serotonin. Ingestion of four bananas (a food rich in serotonin) increased urinary 5-HIAA but not urinary serotonin excretion of seven normal subjects. Evidently, measurement of urinary serotonin excretion is helpful in the evaluation of patients with suspected carcinoid tumors.

Iodine-131 metaiodobenzylguanidine ([131I]MIBG) is concentrated in pheochromocytomas and can be detected by external imaging. We administered [131I]MIBG to 23 patients with carcinoid tumors to determine if it would be useful in scanning patients with these tumors. The carcinoid tumors of 14 of the 23 patients (61%) were visualized. Iodine-131 MIBG was concentrated most avidly by tumors of midgut origin (ileum, cecum); it was concentrated less avidly by some tumors of foregut origin (pancreas, stomach); it was not significantly concentrated by other tumors of foregut origin (bronchus). We conclude that 131I is a useful imaging agent for carcinoid tumors.

The importance of estrogens in the dietary lipid alteration of R3230AC mammary carcinoma growth and insulin binding was studied. Animals were divided into three groups [intact, ovariectomized, and ovariectomized treated with estradiol valerate (EV)] and were fed diets containing either 0% fat (fat free), 0.5% corn oil (low fat), or 20% corn oil (high fat). An alteration of tumor burden between animals fed high-fat versus either low-fat or fat-free diets was observed and appeared to be influenced by the estrogen status of the animal. The difference in tumor burden attributed to dietary lipid seen in intact rats was less in ovariectomized rats and greater in ovariectomized rats treated with EV, despite the fact that absolute tumor burden was reduced by this treatment. A similar relationship was observed for dietary lipid-induced differences in insulin binding to plasma membranes from these tumors. Reduction of tumor growth resulting from estrogen treatment was greater in low-fat- and fat-free-fed animals than in high-fat-fed rats. Again, tumor growth behavior appeared to be related to the reduction of insulin binding induced by estrogen treatment; insulin binding to plasma membranes from animals fed a low unsaturated lipid diet was decreased to a greater extent by EV treatment than in membranes from high-fat-fed rats. Altered tumor growth and membrane insulin binding, resulting from dietary perturbations and/or EV treatment, were not invariably related to serum insulin levels, nor to differences in membrane preparation, as reflected by 5'-nucleotidase activity, nor to membrane fatty acid composition or uptake of proline. Taken together, these results suggest a potential role of estrogens and insulin receptors as mediators of the dietary lipid alterations of growth of the R3230AC mammary carcinoma.

The purpose of this study was to determine if there is a difference in the biochemical composition of the edge of a tumor and the center of a tumor. There was a greater concentration of histamine in the edge (mean +/- SEM, 9.3 +/- 1.2 pmole/mg of wet weight) than in the center (3.6 +/- 0.4 pmole/mg of wet weight) of a transplantable golden hamster insulinoma. There was, however, no difference in the concentration of norepinephrine, protein, DNA, or phosphate, or in the activity of the enzymes, monoamine oxidase, catechol-O-methyltransferase, L-dopa decarboxylase, or 5'-nucleotidase in the edge or in the center of the tumor. Using chemical analysis and autoradiography, there was a comparable incorporation of tritiated thymidine in the edge and in the center of the tumor.

The urinary excretion of 5-hydroxyindoleacetic acid, 5-hydroxytryptophan, serotonin, tryptamine, and tyramine and the serum serotonin concentration were determined in 38 consecutive patients with metastatic carcinoid tumors. Four of the 23 patients with the carcinoid syndrome (15%) had markedly elevated excretion of 5-hydroxytryptophan. None of the patients had markedly elevated excretion of tryptamine or tyramine; a substantial number of patients had moderately low urinary excretion of these amines. All of the patients with the carcinoid syndrome had elevated urinary 5-hydroxyindoleacetic acid excretion; 2 of these patients had normal serum serotonin concentrations, suggesting that quantitative 5-hydroxyindoleacetic acid excretion is the most reliable test for the carcinoid syndrome. Although tryptamine secretion by carcinoid tumors is rare, 5-hydroxytryptophan secretion may be more common than is recognized.

TOMATO spotted wilt virus (TSWV) is characterized by its marked instability in vitro. A reflexion of this situation is the fact that there are no reports in the literature on the production of an active antigen preparation and of an antiserum for TSWV. In addition, Matthews1 points to a personal communication by Bawden, according to whom TSWV is among those viruses giving negative results in serological tests.