Skin sympathetic vasoconstrictor response to static maximum inspiratory breath-holds: effects of breath-hold duration / 中华物理医学与康复杂志

Objective To quantify the temporal changes in the volume of blood flow to the skin of the forearm and lower leg during static maximum inspiratory breath-holding of different durations.Methods Blood flow to the skin of the forearm and lower leg were continuously measured with laser Doppler flowmetry in 12 healthy subjects.They were randomly selected to hold their breath for 10,20 or 40 seconds,or as long as possible.The volume of skin blood flow,the onset latency and the recovery latency were measured before,during and after the breath holding.Results Blood flow decreased significantly during each breath-hold with any durations.The magnitude of the decrease and its latencies were similar with all the durations.The average volume of skin blood flow and it's minimum value during each breath-hold were significantly lower in the forearms than in the lower legs.However,the average onset latency (4.41 ±0.44 s) and the average recovery latency (5.95 ±0.59 s) in the forearms were significantly shorter than in the lower legs (4.83 ± 0.70 s for onset and 7.33 ± 0.91 s for recovery).Conclusion The volume of skin blood flow decreases during a static maximum inspiratory breath-hold,and the magnitude of the increase is not related to the duration of the breath-hold.The generalized increase in skin sympathetic vasoconstrictor activity during a static breath-hold is greater in the forearm than in the lower leg.

Clinical study on intrauterine hemorrhagic fever with renal syndrome virus infection / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To find out the status of intrauterine infection with hemorrhagic fever with renal syndrome virus (HFRSV).</p><p><b>METHODS</b>The blood of mothers and the umbilical cords were examined by using anti-HFRSV-IgG at labor of mothers infected with HFRSV. The venous blood of naturally delivered babies were examined for anti-HFRSV-Ig M, HI test was used to type the HFRSV.</p><p><b>RESULTS</b>Mothers blood showed positive reaction for anti-HFRSV-IgG. Twenty-three of 27 cases of the fetal death were umbilical cords blood positive two out of twelve of umbilical cord blood that the babies were born naturally after their mothers recovered showed positive for anti-HFRSV -IgG but negative for anti-HFRSV-IgM, 14 babies born naturally normally.</p><p><b>CONCLUSIONS</b>HFRSV can cause intrauterine infection, and lead to fetal death, but no post natal deformity was observed in the babies born naturally.</p>