Abstract：
:These experiments tested the hypothesis that phototropic bending arises when a light gradient across the stem differentially inhibits cell elongation because of direct inhibition of cell elongation by light (the Blaauw hypothesis). Continuous irradiation of dark-grown cucumber seedlings (Cucumis sativus L.) with unilateral blue light inhibited hypocotyl elongation within 30 s, but did not induce phototropic curvature until 4.5 h after the start of irradiation. Marking experiments showed that curvature began simultaneously at the top and bottom of the growing region. In situ measurements of the light gradient across the stem with a glass fiber optic indicated that a 5- to 6-fold difference in fluence rate was established on the two sides of the stem. The light gradient established at the start of irradiation was the same as that after 6 h of irradiation. Changes in gravitropic responsiveness during this period were also ruled out. Calculations show that the light gradient should have caused curvature which would be detectable within 30 to 60 min and which would extrapolate to the start of irradiation--if the Blaauw hypothesis were correct. The long lag for phototropism in this case indicates that rapid inhibition of cell elongation by blue light does not cause the asymmetrical growth of phototropism. Rather, phototropism is superimposed upon this separate light growth response.
journal_name
Photochem Photobioljournal_title
Photochemistry and photobiologyauthors
Cosgrove DJdoi
10.1111/j.1751-1097.1985.tb01642.xsubject
Has Abstractpub_date
1985-01-01 00:00:00pages
745-51issue
6eissn
0031-8655issn
1751-1097journal_volume
42pub_type
杂志文章abstract：:During the photoreaction cycle of photoactive yellow protein (PYP), a physiologically active intermediate (PYP(M)) is formed as a consequence of global protein conformational change. Previous studies have demonstrated that the photocycle of PYP is regulated by the N-terminal loop region, which is located across the ce...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.2008.00375.x
更新日期：2008-07-01 00:00:00
abstract：:Muscle injuries represent ca 30% of sports injuries and excessive stretching of muscle causes more than 90% of injuries. Currently the most used treatments are nonsteroidal anti-inflammatory drugs (NSAIDs), however, in last years, low-level laser therapy (LLLT) is becoming an interesting therapeutic modality. The aim ...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.2012.01236.x
更新日期：2013-03-01 00:00:00
abstract：:The photochemistry of caged compounds of the o-nitrobenzyl type has been investigated thoroughly in the past. However, even recently new side reactions have been discovered. Earlier, we reported [Bley, F., K. Schaper, and H. Görner (2008), Photochem. Photobiol.84 162-171] that we found long-lived triplet states which ...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.2009.00560.x
更新日期：2009-09-01 00:00:00
abstract：:Channelrhodopsins act as photoreceptors for control of motility behavior in flagellates and are widely used as genetically targeted tools to optically manipulate the membrane potential of specific cell populations ("optogenetics"). The first two channelrhodopsins were obtained from the model organism Chlamydomonas rei...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.2011.01027.x
更新日期：2012-01-01 00:00:00
abstract：:We calculated the integrated UVB and plant damage irradiances for Argentina, a country in the Southern Hemisphere spread over a large latitudinal range. The irradiances were calculated for clear sky days using the Madronich code for the average conditions of the months corresponding to the summer and winter solstices ...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：
更新日期：2002-09-01 00:00:00
abstract：:Unlike the enchanting yellow-green flashes of light produced on warm summer evenings by Photinus pyralis, the most common firefly species in North America, the orange lights of Photinus scintillans are infrequently observed. These Photinus species, and likely all bioluminescent beetles, use the same substrates beetle ...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/php.12671
更新日期：2017-03-01 00:00:00
abstract：:Patients infected with human immunodeficiency virus (HIV) have a high prevalence of UV radiation-responsive skin diseases including psoriasis, pruritus, eosinophilic folliculitis and eczemas. On the other hand, UV has been shown to suppress T cell-mediated immune responses and to induce activation and replication of H...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章,评审
doi：10.1111/j.1751-1097.1996.tb02450.x
更新日期：1996-08-01 00:00:00
abstract：:The photodynamic effect of hypericin on EMT6 mouse mammary carcinoma cells was investigated in vitro under aerobic and hypoxic conditions. Under aerobic conditions, hypericin-induced photocytotoxicity was dose dependent within a 1-50 microM range. Under hypoxic conditions, cells were resistant to hypericin-induced pho...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.1992.tb08531.x
更新日期：1992-06-01 00:00:00
abstract：:Microscopic fluorescence photometry incorporating a light-sensitive thermo-electrically cooled charge-coupled device (CCD) camera was employed to investigate the fluorescence distribution of 5-aminolevulinic acid (ALA)-induced porphyrins in 22 patients with a total number of 52 noduloulcerative basal cell carcinomas (...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.1995.tb09154.x
更新日期：1995-11-01 00:00:00
abstract：:Fibrous proteins discolor on exposure to the UV component of sunlight. This effect is exacerbated in the presence of fluorescent whitening agents (FWAs), which are often applied to textiles to improve product brightness. Tryptophan photoproducts have been identified as significant contributors to protein photoyellowin...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.2009.00614.x
更新日期：2009-11-01 00:00:00
abstract：:We describe here the development of monoclonal antibodies to the hapten tryptophan-riboflavin, generated by irradiation of a solution of bovine serum albumin in the presence of riboflavin. The specificity of the three obtained monoclonal antibodies, named 1E6, 5H5, 5A8 all belonging to the IgG1 isotype, was assessed b...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.1996.tb09628.x
更新日期：1996-06-01 00:00:00
abstract：:To determine the impact of delivery vehicles in photosensitizing efficacy of HPPH, a hydrophobic photosensitizer was dissolved in various formulations: 1% Tween 80/5% dextrose, Pluronic P-123 and Pluronic F-127 in 0.5%, 1% and 2% phosphate buffer solutions (PBS). HPPH was also conjugated to Pluronic F-127, and the res...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/php.13183
更新日期：2020-05-01 00:00:00
abstract：:As the most important interface between human body and external environment, skin acts as an essential barrier preventing various environmental damages, among which DNA-damaging UV radiation from the sun remains the major environmental risk factor causing various skin diseases. It has been well documented that wavelen...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/php.12462
更新日期：2015-07-01 00:00:00
abstract：:Fabrea salina is a marine ciliate that shows photomotile responses such as positive phototaxis and a step-down photophobic reaction. We found that preilluminated F. salina cells show a phototactic response significantly greater than that of dark-adapted cells when exposed to the same phototactic light stimulus. In par...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1562/0031-8655(2003)077<0204:eopopr>2.0.co;2
更新日期：2003-02-01 00:00:00
abstract：:The in vitro cell survival, localization and ultrastructural changes following irradiation were examined in 9L glioma cells sensitized with a new photosensitizer, lysyl chlorin p6 (LCP). In clonogenic assays, LCP was 10-100-fold more phototoxic than photofrin II on a microgram/mL basis. Lysyl chlorin p6 uptake was blo...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.1993.tb04948.x
更新日期：1993-11-01 00:00:00
abstract：:Photodynamic treatment is often thought to produce reactive oxygen species (ROS) that directly induce killing; the nomenclature and phrases revolve around such notions of light-dependency. Few studies reference the possible existence of oxidation products formed in secondary reactions, which bear cytotoxicity competit...
journal_title：Photochemistry and photobiology
pub_type： 评论,杂志文章
doi：10.1111/php.12984
更新日期：2019-01-01 00:00:00
abstract：:Seafarers working on decks of vessels at low latitudes are exposed to extremely high solar UV radiation. Their risk of developing skin cancer may be enhanced. Solar erythemal UV irradiance and exposure were measured for the first time on merchant vessels going along typical international routes at low latitudes. The m...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/php.12144
更新日期：2013-11-01 00:00:00
abstract：:The effect of netropsin on the oxidative reactions of duplex DNA was examined. One-electron oxidation of DNA creates a radical cation that migrates through duplex DNA and reacts primarily at GG steps. Netropsin is a dication that specifically binds primarily by hydrogen bonding in the minor groove at sites that have f...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1562/0031-8655(2004)080<0456:EONOOO>2.0.CO;2
更新日期：2004-11-01 00:00:00
abstract：:Chaetopterus variopedatus has been studied for over a century in terms of its physiology, ecology and life history. One focus of research is on its intrinsic bioluminescent emissions, which can be observed as a blue light emitted from the extremities of individual body segments, or as a secreted mucus. Even though res...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章,评审
doi：10.1111/php.13221
更新日期：2020-07-01 00:00:00
abstract：:We study the fluorescence lifetime of the well-known 1-pyrene butyric acid (PBA) to assess oxygen concentrations in living cells. The behavior of the probe is first studied in water, ethanol, protein solution and liposome suspension. The Stern-Volmer plot of these solutions is linear, and the bimolecular reaction rate...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1562/2004-03-11-RA-109
更新日期：2004-09-01 00:00:00
abstract：:Phage T7 can be used as a biological UV dosimeter. Its reading is proportional to the inactivation rate expressed in HT7 units. To understand the influence of phage proteins on the formation of DNA UV photoproducts, cyclobutane pyrimidine dimers (CPD) and (6-4)photoproducts ((6-4)PD) were determined in T7 DNA exposed ...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：
更新日期：1999-05-01 00:00:00
abstract：:The photobiologic properties of a chlorin-thiobarbiturate conjugate were examined. In addition to the characteristic 670 nm chlorin absorbance, the conjugate exhibited new absorbance bands at 517 and 743 nm, but these were not a part of the fluorescence emission spectra, nor was fluorescence observed at wavelengths > ...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.1994.tb02981.x
更新日期：1994-05-01 00:00:00
abstract：:Depletion of the ozone layer leads to increasing UV-B radiation on the earth's surface, which may affect weeds and their responses to herbicides. However, the effect of increased UV-B radiation on weeds and the interaction of weeds and herbicides are still obscure. The objective of this study was to compare glyphosate...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.2012.01234.x
更新日期：2012-11-01 00:00:00
abstract：:The pharmacokinetics of Zn phthalocyanine (ZnPc) encapsulated in dipalmitoyl-phosphatidylcholine (DPPC) liposomes, injected intravenously in Skh:HR-1 nude mice, was monitored by two in vitro techniques and one in vivo technique, all based on fluorescence spectroscopy. The in vitro methods involve either fluorescence m...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.1991.tb08475.x
更新日期：1991-01-01 00:00:00
abstract：:Pyrimidine dimers were measured in epidermal DNA of SKH:HR1 mice following exposure to solar-simulated UV radiation (SSUV, 290-400 nm) or to UVA (320-400 nm). Mice were exposed to SSUV or UVA after topical application (2 mg/cm2) of vehicle, a UVB absorber (5% 2-ethylhexyl p-methoxycinnamate [2-EHMC]), or a broad-spect...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.1997.tb07961.x
更新日期：1997-06-01 00:00:00
abstract：:Aqueous solutions of KI were examined for use as chemical actinometers to measure 254 nm (germicidal) radiation. Irradiation results in electron ejection from iodide such that aqueous electrons and iodine atoms are formed. In the presence of N2O, an electron scavenger, recombination of these two reactive species is el...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.1993.tb04986.x
更新日期：1993-12-01 00:00:00
abstract：:Under physiological conditions B-form DNA is an exceedingly stable structure. However, experimental evidences obtained through nuclear magnetic resonance and fluorescence anisotropy suggest that the structure of the double helix fluctuates substantially. We describe photoacoustic phase modulation frequency measurement...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1562/0031-8655(2001)074<0512:aotebb>2.0.co;2
更新日期：2001-10-01 00:00:00
abstract：:Topical 6,4,4'-trimethylangelicin (TMA) plus UVA was used to induce intense epidermal pigmentation in inbred HRA.HRII-c/+/Skh hairless pigmented mice over a 13 day period. Subsequent UVB/UVA exposure was used to assess the photoprotective properties of this tan using skin tumors as an endpoint. Comparisons were always...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：
更新日期：1998-01-01 00:00:00
abstract：:There is a need to improve the selectivity of photodynamic therapy and for better targeting of tumor cells within specific tumor compartments. Selective in vitro phototoxicity of a human bladder carcinoma cell line 647V has been achieved by targeting sulfonated aluminum phthalocyanines (AlSPc) with monoclonal antibodi...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：10.1111/j.1751-1097.1994.tb05139.x
更新日期：1994-11-01 00:00:00
abstract：:Photodynamic therapy (PDT) uses laser light to activate a photosensitizer that has been absorbed preferentially by cancer cells after systemic administration. A phototoxic reaction ensues resulting in cell death and tissue necrosis. Some cells, however, may survive PDT. This study was performed to determine if survivi...
journal_title：Photochemistry and photobiology
pub_type： 杂志文章
doi：
更新日期：1998-10-01 00:00:00
