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81.
This article reviews the transplantation of maxillary canines: indications, contraindications, surgical technique, and success rates. A successful case is illustrated.  相似文献   
82.
The authors report all-optical synchronized multiplication by rational fractions of the modulation frequency of optical signals in self-pulsing two-section semiconductor laser diodes. The effect is based on the overlap of harmonics of the input signal with harmonics of the self-pulsation. This new generic function is illustrated with mode-locked inputs rich in harmonics, where fractions of 1, 2, and 3/2 are generated, and a number of applications for this effect are identified  相似文献   
83.
We have calculated the room temperature gain-current characteristics for a 360 nm wavelength, 80 /spl Aring/ GaN-Al/sub 0.14/Ga/sub 0.86/N and a red-emitting, 80 /spl Aring/ Ga/sub 0.51/In/sub 0.49/P-(Al/sub 0.44/Ga/sub 0.56/)/sub 0.51/In/sub 0.49/P quantum well laser structures, including many body effects. Although the carrier density and spontaneous current are much higher (by a factor of 4 and 3, respectively) in the nitride structures for a given local gain, the higher confinement factor at short wavelengths means the intrinsic threshold current of these devices is predicted to be approximately twice that of red lasers with the same optical loss.  相似文献   
84.
Aqueous humor was taken from 32 patients with senile and presenile cataract at the operation by means of anterior chamber puncture. Uric acid was marked by indirect method with uricase. The mean content of uric acid in aqueous humor of patients with cataract was 187.13 mumol/l and in the control group 309.34 mumol/l. The difference between the groups is statistically significant. The results suggest that uric acid as strong endogenous antioxidant may play an important role in pathogenesis of cataract.  相似文献   
85.
An inter-collaborative tasting exercise was undertaken in which panels at seven different brewing companies compared the flavour of four beers in duplicate. Statistical analysis demonstrated that the results from individual panels were repeatable but there was little consistency between panels. Generalised Procrustes Analysis demonstrated that inconsistencies between panels were due to differences in the use of flavour terminology and differences in the use of scoring scales. It is suggested that consistency could be significantly improved by introducing standardised flavour methods and training across the brewing industry.  相似文献   
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