Sentence examples for have sometimes been observed from inspiring English sources

Exceptional outbreaks, with a higher mortality, have sometimes been observed.

Similar phenomena have sometimes been observed during the development of in vivo radioligands [30] [32].

Clinical infections have sometimes been observed in horses [ 3].

Although these have sometimes been observed to introduce spermatozoa into females this resulted in the degradation of the sperm nucleus [ 32] and reproduction was still mitotic.

In rodent carcinogenesis experiments, chronic toxic lesions, accompanied by increases in normal levels of cell turnover, have sometimes been observed in target organs of nongenotoxic carcinogens.

In developmental studies of molecularly targeted agents, unexpected outcomes of control arms in terms of PFS and OS, disproving the statistical hypotheses, have sometimes been observed.

It is noteworthy that C4 and C6 have appeared frequently since 1996 and 1993, respectively, whereas C5 has sometimes been observed before the early 1990s.

Re-growth of pathogens or indicator bacteria has sometimes been observed during post-treatment and storage of Class A biosolids (Iranpour et al. 2002a, b; Ward et al. 1999).

Courtship feeding of the female by her partner has sometimes been observed.

A reverse pattern of differential concentrations of biomolecules between brain and peripheral blood samples has sometimes been observed.

The clinical prognosis for progressive multifocal leukoencephalopathy is usually poor, with most cases resulting in death within 6 months, although prolonged survival has sometimes been observed [ 7, 8].