| 1 | Effect of bowel rehabilitative therapy on structural adaptation of remnant small intestine: animal experiment显示文摘AIM To investigate the individual and thecombined effects of glutamine, dietary fiber,and growth hormone on the structural adaptationof the remnant small bowel.METHODS Forty-two adult male Sprague-Dawley rats underwent 85% mid-small bowel( TPN ) support during the first threepostoperational days. From the 4thpostoperational day, animals were randomlyassigned to receive 7 different treatments for 8days: TPNcon group, receiving TPN and enteral20 g.L- 1 glycine perfusion; TPN + Gin group,receiving TPN and enteral 20 g.L-1 glutamineperfusion; ENcon group, receiving enteralnutrition (EN) fortified with 20 g@L-1 glycine; EN+ Gin group, enteral nutrition fortified with20g. L-1 glutamine; EN + Fib group, enteralnutrition and 2 g. d- 1 oral soybean fiber; EN + GHgroup, enteral nutrition and subcutaneousgrowth hormone (GH) (0.31U) injection twicedaily; and ENint group, glutamine-enriched EN.oral soybean fiber, and subcutaneous GHinjection.RESULTS Enteral glutamine perfusion duringTPN increased the small intestinal villus height(jejunal villus height 250 μm ±29 μm in TPNconvs 330 μm ± 54 μm in TPN + Gin, ileal villus height260μm±28μm in TPNcon vs 330 μm±22μm inTPN + Gin, P<0.05) and mucosa thickness( jejunal mucosa thickness 360 μm ± 32 μm inTPNcon vs 460 μm ± 65 μm in TPN + Gin, ilealmucosa thickness 400 μm ± 25 μm in TPNcon vs490μm ± 11 μm in TPN + Gin, P<0.05) incomparison with the TPNcon group. Either fibersupplementation or GH administration improvedbody mass gain (end body weight 270 g ± 3.6 g inEN+Fib, 265.7 g ± 3.3 g in EN+GH, vs 257g±3.3g in ENcon, P<0.05), elevated plasmainsulin-like growth factor ( IGF-Ⅰ ) level(880 μg. L-1 ± 52 μg. L-1 in EN + Fib, 1200 μg. L-1± 96 μg. L- 1 in EN ± GH, vs 620 μg. L-1 ±43 μg. L-1 in ENcon, P<0.05), and increased thevillus height (jejunum 560 μm ± 44 μm in EN ± Fib,530 μm± 30 μm in EN ± GH, vs 450 μm ± 44 μm inENcon, ileum 400 μm ± 30 μm in EN + Fib, 380 μm±49 μm in EN± GH, vs 320 μm± 16 μm in ENcon,P<0.05) and the mucosa thickness (jejunum740 μm ± 66 μm in EN ± Fib, 705 μm ± 27 μm in EN ±GH, vs 608 μm ± 58 μm in ENcon, ileum 570 μm ±27 μm in EN ± Fib, 560 μm ± 56 μm in EN ± GH, vs480μm ± 40 μm in ENcon, P<0.05) in remnantjejunum and ileum. Glutamine-enriched ENproduced little effect in body mass, plasma IGF-Ⅰ level, and remnant small bowel mucosalstructure. The ENint group had greater bodymass (280g ± 2.2g), plasma IGF-Ⅰ level(1450g@L-1 ± 137g. L 1), and villus height(jejunum 620 μm ± 56 μm, ileum 450 um ± 31 μm)and mucosal thickness (jejunum 800 μm ± 52 μm,ileum 633 μm± 33 μm) than those in ENcon, EN +Gin (jejunum villus height and mucosa thickness450 μm ± 47 μm and 610 μm ± 63 μm, ileum villusheight and mucosa thickness 330 μm ± 39 μm and500 μm± 52 μm), EN + GH groups (P<0.05), andthan those in EN + Fib group although nostatistical significance was attained.CONCLUSION Both dietary fiber and GH whenused separately can enhance the postresectionalsmall bowel structural adaptation. Simultaneoususe of these two gut-trophic factors can producesynergistic effects on small bowel structuraladaptation. Enteral glutamine perfusion isbeneficial in preserving small bowel mucosalstructure during TPN, but has little beneficialeffect during EN. | Xin Zhou1 Yuan Xin Li2 Ning Li2 Jie Shou Li2 1Department of General Surgery, Medical School, Nanjing University, Nanjing 210093. Jiangsu Province. China2Research Institute of General Hospital. Chinese PLA General Hospital of Nanjing Military Area, Nanjing 210002. Jiangsu Province. China | 2001 | World Journal of Gastroenterology2001，7，1： | 14 |
| 2 | Spectral Feature Analysis of Semiconductor Thin Disk Laser显示文摘The semiconductor thin disk laser is a new type of semiconductor laser. This work gives the basic operation function of the semiconductor disk laser, and analyses the heat effect by the experimentally measured photoluminescence spectrum of the laser chip at different pump power and different temperatures. We can see that: with increasing pump power, the thermal effect of the gain material becomes seriously and causes the saturation of carrier lifetime, so the electron-hole pair created in the absorbtion layer has no enough time to rate to one of the wells, and the non-radiative recombination happens in the barrier. When the thermal effect becomes stronger, the chip will be not lasing. This phenomenon is from the smaller energy offset between barrier and quantum well. We optimize the original structure design and experimental technology. A non-absorbing AlGaAs layer which is transparent to the pumping and laser wavelength is added to confine the carriers in the quantum wells. At the same time a DBR with double reflecting band is induced to improve the absorbing efficiency of the pumping light. The single QW is replaced by the three narrow QWs. This three QWs structure can add the quantum state of QW, increase the recombination probability of carriers in the QWs and reduce the heat effect. The chemical etching equipment is also improved to control the surface unevenness to be within 50 nm. | (HE Chun-feng1, QIN Li2, LI Jun1, CHENG Li-wen1, LIANG Xue-mei1, NING Yong-qiang2, WANG Li-jun2 1. Key Laboratary of Excited State Processes, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences,Changchun 130033, China Graduate School of the Chinese Academy of Sciences, Beijing 100049, China 2. Key Laboratary of Excited State Processes, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033,China.) | 2007 | 光机电信息2007，24，12： | 1 |
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