CONCEPT AND SIGNIFICANCE 13 rays from radioactive substances upon the cellular components of the skin. b) Pulmonary blastomas resulting from the exposure to and inhalation of radio active material, chromates, asbestos, nickel carbonyl, tarry substances. c) Tumors of the nasal passages and sinuses following upon the exposure to radioactive substances, chromates, nickel carbonyl. d) Cancers of the upper alimentary tract exhibit statistically causal relations to certain industrial cancerigenic agents acting most probably directly upon the mucous membranes of these passages. 2) Excretory contact tumors. a) Epithelial neoplasms of the skin following the ingestion of arsenicals. b) Blastomas of the urogenous tract resulting from an exposure to certain aromatic amines, excreted in the urine. c) Cancers of the liver, intestinal tract, female genital organs provide, theoreti cally, a possibility of proliferative manifestations of this type. 3) Depository contact tumors. a) Cancers of the skin associated with the deposition of arsenicals in the cells of this organ. b) Sarcomas of the bony tissues following the storage of radio-active material in the bones. 4) Tumors in tissues possessing a special affinity or sensitivity to a particular cancerigenic agent. a) Blastomatoid and blastomatous reactions of the hematopoietic tissues follow ing an exposure to roentgen-rays, radioactive substances, benzol, and chemi cally related substances. b) Cancers of the urinary bladder and liver caused by an infestation with certain helminthic parasites exhibiting an affinity to these organs.

TUMORS OF THE SKIN 73 sition of the tar, as reflected by the relative proportions of the various frac tionation products which can be extracted from such tars.

146 OCCUPATIONAL TUMORS AND ALLIED DISEASES lightest fraction following the separation of benzine, i .5 per cent of the total oils is represented by "yellow oil", employed as fuel in Diesel engines.

TUMORS OF THE SKIN 291 following a frost-bite suffered two years previously.

CANCERS OF THE RESPIRATORY SYSTEM 389 individual animal (Andervont; and Lynch).

4i4 OCCUPATIONAL TUMORS AND ALLIED DISEASES for the occurrence of cancer, did not reveal any evidence supporting the conception that heredity plays any part in the production of pulmonary malignancy in chromate workers (A1wens).

548 OCCUPATIONAL TUMORS AND ALLIED DISEASES the location of the causative agent in regard to site and type of proliferating epithelial cells.

sc 008146 LAM009356 :t> u AM < .1 l4M&rii>^<8ir iSVi-nm* .

PRICES SHOWN HEREIN ARE SUGGESTED LIST PRICES.

GENERAL SERVICE ITEMS AND ACCESSORIES Class Part No.

STATE OF NEW J ERSEY File answer at........

MCC "-.'

NAPA AUTOMOTIVE CAREER TRAINING Passenger Comfort - Air Conditioning - Continued Evaporator ary control valves help sense and further regulate evaporator pressure to prevent freeze-up during operation.

i i % When the pressure in the system drops below the pressure exerted by the piston return spring, the check valve will be forced against its seat to stop the flow of fluid from the system to the master cylinder.

o N c <O o J tf-t 1 x H IL r~ n-- rr X< oCd LL C/) " cc WN L- O cf- 3i "Ti n *-r 0 cC *" "^c !