منابع مشابه
New ivory worries
Species (Cites) in 1989, to halt the steep decline in elephant numbers. “Wild elephant populations were decimated by the ivory trade. By the time the 1989 Cites ban came into force, Africa’s elephants had been reduced by more than 50 per cent,” says Mark Jones, programmes director at Care for the Wild, an international wildlife charity which commissioned the mammoth ivory report. “Poaching cont...
متن کاملNew Insights to Old Problems
From the history of the θ-τ puzzle and the discovery of parity non-conservation in 1956, we review the current status of discrete symmetry violations in the weak interaction. Possible origin of these symmetry violations are discussed. PACS: 11.30.Er, 12.15.Ff, 14.60.Pq
متن کاملCommentary Tuberculosis: Old problems and new approaches
In New York City from 1985 to 1992, reported cases of tuberculosis rose by more than 20%. This followed a 30-year period of decline in the incidence of the disease. The reasons for the reversal are many and include the role of HIV-1 infection in enhancing disease progression and transmission, homelessness in the city, the emergence of multi-drug-resistant strains of the etiological agent (Mycob...
متن کاملThyroid Emergencies: New Insight into Old Problems.
Thyroid emergencies are major life-threatening endocrine conditions associated with life-threatening disorders resulting from either severe deficiency or excess of thyroid hormones. Deficiency of thyroid hormones may present as myxedema coma whereas excessive hormone production can present as life threatening thyrotoxic storm. The diagnosis of both requires a high index of clinical suspicion. T...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Nature
سال: 1990
ISSN: 0028-0836,1476-4687
DOI: 10.1038/345756b0