Document Jr2L9yGKQj0jMND4zQgMvqVjK

14 January 19$} 14 januorie 1061 S. A. T y D 3 k bip vir Gbneebkundb 29 king om die akuti lliserieltrinitr&at (jn Amielnitriet Is nie tog nog aanbevet) ng verlang word, rd (nitro-gliserien) del In die lewq 1 van krag as die dit neem 'n rukkle' r dit duur ook wetr wat ingeasem word, word dus deur die , bepaal. Dit is ool eer nie teenwoordi| in hierdie .njlraal' :t, maar hulle word leenhouers is van korboksasled, (endulle het ,'n uitwer--.die sogenoemde, iervan mag wel van tartkramp, maar die : benader te word, jeruime tyd lank al it ook die geval is /ergelyking met die voordeel aangedui uddels is wat wel Id nitriete die enigste tile die kroonslsgare wya dat die. meeste sou h&. wel effekte het egter nie 'a ien omrede van die behoefte op hierdie wat aan *n aader irteen toleransie nie >/ Choice. St. Louis: ICA nesburg Oenerul h African Council ases which we our- IAQNOSIS leural mesotheliomas een thrown on their ' and WiUis.* Primary ; ere described by . Klemperer and Rabin* end Stout and Murray.' Recently moorts concerning these tumours have appeared Irom various countries; these include those of Tobiassen,* Bellini and Bovo,' Oodwin' aod McCaughey.* The dlagnosis in our cases has been confirmed by South African nHiholosists and well-known authorities from Britain and the USA, including Dible," Oough," Steiner,0 Stewart," and Vorwald." Diffuse pleural mesothelioma is generally considered a rare tumour. Daub and Jones" reported 3 cases among 345 000 consecutive admissions to the Henry Ford Hospi tal The largest series thBt we have been able to find in the literature is that of Cboptal ei a/." who described 22 cases seen over a period of many years. In contrast, our larger group has been diagnosed mainly during the last 4 years, ft must be stressed that we have only included cases in which the nature of tbo tumour has been confirmed histologically, either on biopsy- or necropsy material. A number of cases showing radiological and clinical features only have beon, excluded. Three of these cases had markedly abnormal cells in the pleural fluid. ASSOCIATION WITH ASBESTOS This frequency of mesotheliomas is possibly significant in its apparent association with areas where asbestos is mined or milled. Evidence in support of this has already been presented1 and includes: 1. Tbo finding of asbestos bodies in the lungs of 12 (30%) of the 41 patients with mesotheliomas, even though in the majority of the earlier cases, before the association was suspected, the biopsies usually consisted of tissue from the parietal pleura only. Asbestos bodies have been found In 9. of 11 biopsies in which lung parenchyma was in cluded. Evidence of asbestosis has been observed in 6 out of the 7 cases in which the lungs have been examined at necropsy. 2. The fact that 19 of these patients worked with asbestos, either as miners, millers or industrial workers. 3. The fact that all except 2 of the other 22 cases were either bom, or spent a significant period'of their lives, in . the asbestos area of the north-western Cape Province. Asbestos Bodies in the Sputum Further, one of us (C.A.S.), working on the -clinical hypothesis that exposure to asbestos causes ou increased pleural reaction in patients suffering from tuberculosis, submitted numerous sputa from the West End Hospital, Kimberley, to tbe Pneumoconiosis Research Unit for ex amination. Asbestos bodies and fibres were found in the sputa of 115 patients who had no definite mining expo sure. Included in these were specimens from people work ing in a dry-cleaning works and abattoirs in the North West Capo in places 100 miles away from the nearest minea Tbe presence of asbestos bodies and fibres in tbe . sputum is naturally only indicative of exposure to asbes tos dust and is not evidence of asbestosis unless there is clinical and radiological support However, from these findings it would appear that people possibly not asso ciated with asbestos production or utilization, have been exposed to the hazard. Asbestos fir tfie North West Cape The area of the asbestos deposit in the North West ASBESTOS HILLS Fig. 1. Map showing asbestos deposits in (be Cape Province. Cape, tbe most extensive in tbe world, extends from 20 miles south of the Orange River north to tbe Bechuanaland border, covering approximately 8,000 square miles. Tbe deposits are mainly in the slopes of tbe Asbestos Mountains, a range extending more or less longitudinally between 22-30" and 23"E (Fig. 1). Mining and Milling The type of asbestos mined throughout this area is crocidolite,. better known as Cape blue asbestos. Grocidolite is the fibrous form of riebeckite. All stages of transformation, from massivo riebeckite rock through lamellar riebeckite to asbestiform crocidolite, occur in this region. Magnetite iB frequently associated with tbe croddolite (Vermaaa"). Mining of asbestos first began in the Prleska district in 1893 ahd gradually spread northward. In 1908, production had begun m the Kururoan district This northward trend has continued and, in about 1950, mining started at Pom-Pom, near the Becbuanaland border. (Fig. 2 shows, graphically, the asbestos production from 1910 - 1958.) Initially the ore was quarried in numerous small open-cast workings. This wob followed gradually by a type of shallow mining;'inclined shafting became more common after 1930. Since the 1939 1945 war, tbe demand for crocidolite has increased enormously. Since, doeper and-richer deposits have been found, vertical shafts arc being sunk.. However, the mines with large shallow deposits continue to .use the inclined shaft and tunnel, ond quarrying is still used by t