The Z and W sex chromosomes of birds have evolved independently from the mammalian X and Y chromosomes [1]. Unlike mammals, female birds are heterogametic (ZW), while males are homogametic (ZZ). Therefore male birds, like female mammals, carry a double dose of sex-linked genes relative to the other sex. Other animals with nonhomologous sex chromosomes possess "dosage compensation" systems to eq...

The results of 49 serum gentamicin assays from children of 2 weeks to 11 years of age are presented. The dose of gentamicin given 8-hourly intramuscularly ranged from 0-7 mg/kg-4-9 mg/kg. Doses of 1-7 mg/kg or less did not give adequate serum concentrations. As a result of these observations it is suggested that an intramuscular dose of 2-5 mg/kg given 8-hourly is suitable for most children in ...

The X-linked white gene when transposed to autosomes retains only partial dosage compensation. One copy of the gene in males expresses more than one copy but less than two copies in females. When inserted in ectopic X chromosome sites, the mini-white gene of the CaspeR vector can be fully dosage compensated and can even achieve hyperdosage compensation, meaning that one copy in males gives more...

Dosage sensitivity is an important evolutionary force which impacts on gene dispensability and duplicability. The newly available data on human copy-number variation (CNV) allow an analysis of the most recent and ongoing evolution. Provided that heterozygous gene deletions and duplications actually change gene dosage, we expect to observe negative selection against CNVs encompassing dosage sens...

The usefulness of quinidine in treatment of cardiac arrhythmias is often limited by the difficulty of determining adequate dosage. When control has not been effected by small doses, the physician may be deterred from increasing these because of the risk of toxicity. The electrocardiogram does not help to indicate that this may be imminent, since the effects of overdosage (widening of QRS and ve...

Microbicides are topically applied, user controlled dosage forms that are being developed to prevent the transmission of HIV during coitus. Early candidates focused on coitally dependent dosage forms such as gels and creams. More recent development has focused on broadening the coitally dependent options through the introduction of films and fast dissolving tablets. Additionally, it has become ...

Capsules are used for filling different materials like Powders, Granules, Beads, Tablets, Capsules, Pastes etc.. Some of the disadvantages associated with conventional capsule: They are easily tampered with (although techniques exist for preventing this). They are subject to the effects of relative humidity and to microbial contamination. Some of the innovations are targeted to:  Overcome the ...

OBJECTIVE To compare the effects and side effects of low dosage tricyclic antidepressants with placebo and with standard dosage tricyclics in acute phase treatment of depression. DESIGN Systematic review of randomised trials comparing low dosage tricyclics (< or =100 mg/day) with placebo or with standard dosage tricyclics in adults with depression. MAIN OUTCOME MEASURES Relative risk of res...

Somatic X dosage compensation requires two mechanisms: X inactivation balances X gene output between males (XY) and females (XX), while X upregulation, hypothesized by Ohno and documented in vivo, balances X gene with autosomal gene output. Whether X dosage compensation occurs in germ cells is unclear. We show that mouse and human germ cells exhibit non-canonical X dosage states that differ fro...