Some Gaps in Our Knowledge of Heredity

Gaps in our knowledge about transmission of vaccine-derived polioviruses.

It has long been known that oral poliovirus vaccine (OPV) viruses are transmissible ¿to some degree¿ between vaccinated individuals and their contacts. This property has generally been considered an advantage of these vaccines, since it can spread immunity, despite the fact that the viruses sometimes revert to virulence and hence can also cause vaccine-attributable paralytic poliomyelitis in v...

Some Aspects of Heredity

Melanoma: What Are the Gaps in Our Knowledge?

C utaneous malignant melanoma (MM) falls into two main groups, based on aetiology [1–3]. First, a small minority of patients have acral MM, in which the disease occurs on the palms and soles. The incidence of acral MM is similar in people with widely different skin colours (and hence with different amounts of skin melanin), and at different latitudes. The palms and soles have a thick epidermis,...

Some Gaps in Our Knowledge of the Seasonal Variation in Reproductive Activity of Ewes of Merino and Related Breeds

The behaviour was similar in the ewes of the two breeds. When rams were introduced among ewes in the late summer and autumn, mating always commenced immediately, and most ewes mated within the first three to four weeks. On some occasions when rams were introduced in the spring, there was a delay before mating began; on most other occasions the initial rate of mating was rather low and in most i...

A Re-analysis of Our Current Understanding of Isthmus-Dependent Atrial Flutter: Some Gaps, Some Hypotheses

The macro-reentrant circuit of isthmus-dependent atrial flutter (AFL) is located in the right atrium around the tricuspid annulus. High acute success and low recurrence rate makes isthmus ablation a definitive therapy for patients with only AFL. However, a review of the literature suggests that, different aspects of this macro-reentrant circuit are still not entirely understood, while new infor...