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81.
From January, 1962, through December, 1973, 1,084 patients with cancer of the intrinsic larynx were treated at the Mayo Clinic. Of the 1,084 patients, 136 were retreated after radiation therapy failed to cure their cancer (105 glottic, 30 supraglottic, and one subglottic cancers). Recurrence of glottic cancer was generally recognized later than recurrences in the supraglottic area; likewise, glottic cancers were more advanced at recurrence than supraglottic growths. When feasible, conservation surgery was carried out on both glottic and supraglottic growths. Unfortunately, many growths were too advanced for conservation surgery by the time recurrence was recognized. The concept of "radiate-and-watch" for early glottic and supraglottic cancers is designed to save larynges. The concept is not supported by this study.  相似文献   
82.
Orange RN (monosodium salt of 1-phenylazo-2-naphthol-6-sulphonic acid) was administered to female pigs either by intraveneous injection or by stomach tube. After intravenous injection of Orange RN, 7.8 mg/kg, the following metabolites were indentified in 24-hour urines: Orange RN (31%), 1-(4-hydroxyphenlazo)-2-naphthol-6-sulphonic acid (3%), p-aminophenol and 0-aminophenol (34% and 4% of the theoretical yield, respectively). 1-Amino-2-naphthol-6-sulphonic acid was present, but not determined. When the urine collection was extended to 72 hours the excretion of p-aminophenol accounted for the remainder of the phenylazo moiety. The excretion pattern for p-aminophenol suggest that Orange RN is partly excreted in the bile and thereafter undergoes azo reduction in the gut. After administration of Orange RN, 78 mg/kg, by stomach tube the following metabolites were identified in the urine: Total coloured metabolites (Orange RN and 1-(4-hydroxyphenylazo)-2-naphtholphenol-6-sulphinic acid) (0.4% of the theoretical yield), p-aminophenol and o-aminophenol (52% and 6% of the theoretical yield, respectively) and aniline (0.3% of the theoretical yield). 1-Amino-2-naphthol-6-sulphonic acid was present, but not determined.  相似文献   
83.
84.
Larval Typhlotriton spelaeus collected from five caves in Pulaski Co., Missouri, were kept as larvae or induced to transform in darkness or continuous fluorescent illumination. Larvae maintained in darkness for 215 and 279 days had smaller eyes, smaller rod inner and outer segments, and fewer metaphase figures in the germinative zone of the neural retina than comparable larvae maintained in light (258 lux). Except for visual cell size, differences were small and for each characteristic exceptions were observed. One larva kept in light showed early retinal degeneration comparable to that in transformed adults to T. spelaeus. All larvae exhibited optomotor behavior both before and after the experiment. Among animals induced to transform by L-thyroxin and maintained in darkness 111 to 366 days, visual cell and pigment epithelium degeneration was more extensive and more frequent than in animals kept for the same length of time in light (237-298 lux). In darkness the frequency of animals with retinal degeneration increased between 111 and 366 days. In light some animals exhibited pigment epithelium reduction with normal visual cells, and others had free, pigmented cells in the subretinal space. These effects were not comparable to degeneration in darkness. Eyelids covered the eyes of only a few animals in both light and dark treatments. The extent of eyelid encroachment over the eye greater in darkness than in light. Most animals exhibited optomotor responses after experiments, but responses of animals kept in darkness were impaired in comparison to those of animals kept in light.  相似文献   
85.
86.
Purified Semliki forest virus in aerosols is inactivated rapidly at 40% and above 70% relative humidity. At all humidities tested the decay of virus infectivity runs parallel with the decrease in hemagglutination activity, whereas the biological integrity of the virus ribonucleic acid is preserved. Also, free infectious ribonucleic acid is stable after spraying at all relative humidities. Evidence is presented for the hypothesis that above 20% relative humidity, virus inactivation in aersols is mainly due to surface-dependent factors, damaging the virus coat.  相似文献   
87.
Induction of labor by acupuncture electro-stimulation was carried out in 31 patients. This was successful in 21 cases. The pattern of uterine contractions induced in these patients was similar to that in normal labor. No serious fetal or maternal complications occurred. The delay between the commencement of stimulation and the onset of contractions suggests that a humoral mechanism may be involved.  相似文献   
88.
89.
Fifth patients had bilateral intracapsular cataract extractions with a peripheral iridectomy in one eye and a sector iridectomy in the opposite eye. There was no difference in photophobia between the two eyes in 78% of patients. Twelve percent of the patients had greater photophobia in the eye with the peripheral iridectomy, and 10% had greater photophobia in the eye with the sector iridectomy.  相似文献   
90.
Poly(2-aminoadenylic acid): interaction with poly(uridylic acid)   总被引:1,自引:0,他引:1  
Poly(2-aminoadenylic acid) forms both double and triple helices with poly(uridylic acid) [poly(U)]. The 2-amino group forms a third hydrogen bond, elevating the 2 leads to 1 transition temperature by 33 degrees C. The third strand, however, has about the same stability as poly(A)-2poly(U), as measured by Tm 3 leads to 2. This selective stabilization of the two-stranded helix results in a much greater resolution of the differnt thermal transitions than that observed in analogous polynucleotide systems. In contrast to other A, U systems 3 leads to 1 and 2 leads to 3 transitions are not observed under any conditions, and the triple helix always undergoes a 3 leads to 2 transition even at very high ionic strength. A 1:1 mixture of poly(2NH2A) and poly(U) exhibits no transient formation of 1:2 complex, unlike similar mixtures of poly(A) with poly(U) and poly(T). This difference is evidently due to a more rapid displacement reaction: [poly(2NH2A) + poly(2NH2A)-2poly(U) leads to 2 poly(2NH2A)-poly(U)] With poly(2NH2A) than with poly(A). We describe a method for establishing the combining ratios of polynucleotide complexes which used a computer to calculate the angles of intersection of mixing curves as explicit and continuous functions of the wavelength. The wavelength dispersions of the angles of intersection determine optimum wavelengths for establishing stoichiometry and can also provide reliable negative evidence that presumably plausible complexes are not formed. Analogous computer procedures have been developed to determine wavelengths which are selective for the formation of both 1:1 and 1:2 complexes. Infrared spectra of the 1:1 and 1:2 complexes resemble those of other A, U homoribopolynucleotide helices in having two and three strong bands, respectively, in the region of carbonyl stretching vibrations. CD spectra of the two complexes are unusual in having negative first extrema of moderate intensity. We attribute these extrema to intrastrand interactions of strong, well-resolved transitions at 278 nm (B2u) of the 2-aminoadenine residues. The CD spectra are correlated with those of other polynucleotide helices.  相似文献   
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