Biomedical subjects

Y Mor

Publications and source records attributed to Y Mor.

58 records · Page 4Linked to original sources

PubMed1981

Epinasty of Poinsettias-the Role of Auxin and Ethylene.

Upward physical restraint of the normally horizontal bracts of poinsettia (Euphorbia pulcherrima Willd.) resulted in increased ethylene production and epinastic curvature of the petioles after 5 days. Downward restraint caused little change in ethylene production or epinasty, indicating that the enhanced ethylene production observed in petioles bent upwards is not due to the bending stress alone. Epinasty, measured upon removal of upward physical restraint, was not affected by spraying plants with aminoxyacetic acid to reduce ethylene production or with silver thiosulfate to prevent ethylene action. Removal of the bract blades prevented the epinastic response of the petiole, and the response was restored by applying indoleacetic acid to the cut petiole end. Redistribution of auxin appears to be responsible for both the epinasty and the increased ethylene production of reoriented poinsettia bracts.

Journal Article↗

PubMed1980

Promotion of sink activity of developing rose shoots by light.

Holding young rose shoots (Rosa hybrida cv. Marimba) in darkness while the rest of the plant was in light reduced the amount of (14)C assimilates recovered from the darkened shoot by half. Relative specific activity of the shoot tip grown in light was 13.5 times greater than that of the darkened one. The flower bud at the shoot tip degenerated in darkness and died. Shoots 2 to 3 centimeters long, after flower initiation, were most sensitive to the dark treatment. The degeneration is a gradual and reversible process in the first 8 days of darkness, followed by irreversible damage and atrophy. Darkening enhanced the ability of the young leaves to compete for the available assimilates over that of the darkened shoot tip. The enhancement of the mobilizing ability of the shoot tip by light is independent of photosynthesis since spraying with 3-(3,4-dichlorophenyl)-1,1-dimethylurea or holding shoots in a CO(2)-free atmosphere did not diminish the promoting effect of light on flower bud development or assimilate import. The possibility that light exerts its effect by photoproduction of ATP was also excluded inasmuch as no differences were found in ATP levels of shoot tips held in darkness and those held in light.

Journal Article↗

PubMed1980

Characterization of the light reaction in promoting the mobilizing ability of rose shoot tips.

Mixed fluorescent and incandescent light increased growth and sink strength of the uppermost young shoot of rose plants (Rosa hybrida cv. Marimba) in comparison to pure fluorescent light. This was manifested by increased apical dominance. Monochromatic low-energy red light, given by means of optic fibers for 24 hours to shoot tips that had been previously darkened for 5 days, increased the transport of (14)C-labeled assimilates to the intact tips and the uptake of [(14)C]sucrose by detached tips. Far-red had little or no effect, and blue was not effective at all in these reactions. Red light given directly to detached shoot tips, in vitro, increased the uptake of [(14)C]sucrose by the isolated tips. Adding far-red to the red greatly promoted the uptake, whereas blue and blue plus far-red were not active. The main character of the light reaction promoting sink activity in the shoot is that it is perceived by the shoot tip itself. It is operated by red light; far-red promotes the red effect but has little or no effect when alone. Light apparently promotes shoot sink activity by increasing the unloading process.

Journal Article↗

PubMedDate not supplied

Radical retropubic prostatectomy in the treatment of localized prostate cancer: experience with 100 consecutive cases.

In recent years radical retropubic prostatectomy is used with increasing frequency to treat localized cancer of the prostate. We report our experience with 100 consecutive cases of prostate cancer that underwent this operation; there were no cases of mortality and a 7% rate of postoperative complications. More than 90% of the patients are socially continent postoperatively and 20% have retained sexual potency. Ninety-four percent of the patients are free of disease (mean follow-up period 18 months). In our opinion, such results support the use of radical retropubic prostatectomy for the treatment of localized prostate cancer in well-selected patients.

Adult↗