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51.
Bloodflowvariationandenergymetabolisminthegastricmucosafollowing7.5%hypertonicsalineresuscitationWangJunyi(王俊义);WuGuosheng;(吴...  相似文献   
52.
The microcirculatory architecture of normal tissue, transitional mucosa and adenocarcinoma of the human colon was investigated with microvascular corrosion casting (MVCC) combined with scanning electron microscopy (SEM). The study showed that the capillaries within the normal mucosa were arranged in a regular hexagonal pattern around the mucosal glands and that the microvessels of transitional mucosa mostly had lost the typical hexagonal pattern and become slightly wider in diameter. The microvessels in the tumor periphery were increased in number and disorganized, and presented large variation in morphology with claw-like formations, widened sinuses, diverticula and appendixoid patterns. Microvessels were lacking in the central areas of tumors. These morphological alterations may serve as additional indicators of tumor development.  相似文献   
53.
The authors compared the inhaled methacholine and exercise responses in 22 stable unmedicated asthmatic patients. The exercise and methacholine challenges were performed at one to three week intervals. Bronchial responsiveness to methacholine was measured in relation to the concentration of methacholine (PC20M). The response to exercise was expressed as the percentage of fall in FEV1, from the pre-exercise FEV1 The findings showed that 21 of 22 subjects demonstrated a fall in FEV1, of more than 20% after methacholine challenge, while only 9/22 subjects experienced a similar decrease in FEV1. All 9 of these positive response exercise cases completed three consecutive exercise challenges prior to the methacholine challenge. Of these cases, five were refractory to the repeated exercise challenge, and the PD20M at the nonexercise stage was significantly lower than the postexercise state. In fact, the methacholine challenge sensitivity actually decreased (PD20 increased) after repeated exercise. The authors concluded that methacholine seems to be a more sensitive bronchial provocation test than exercise. Second, only 55.6% of the exercise test-positive subjects were refractory to the second exercise challenge. Therefore, other factors besides the release of mediators should be considered in exercise induced asthma. Third, methacholine sensitivity actually decreased (PD20 increases) after repeat exercise challenge.  相似文献   
54.
本文采用去垢剂透析法成功制备出携载SOD的脂质体(L-SOD),其直径为102nm,对SOD的包裹率为21%,90%以上酶活性存在于脂质体内部。将L-SOD注射到大鼠静脉血中,其半衰期超过4h,明显长于天然SOD(8min)。表明L-SOD优于天然SOD,具有临床应用前景。  相似文献   
55.
56.
本文报告口服Sumatriptan 100mg对偏头痛急性发作119例次的治疗结果。治疗后4h内显效91例次(76.5%),好转16例次(13.4%),无效12例次(10.1%),总有效率为89.9%。对偏头痛伴随症状恶心、呕吐和畏光、畏声的缓解率分别为94.2%、96%和94.3%。  相似文献   
57.
The alpha subunit of the nicotinic acetylcholine receptor (AChR) seems crucial in the pathogenesis of the autoimmune paralysis myasthenia gravis (MG) because it contains both the epitopes that dominate the antibody response against the AChR and those recognized by CD4+ AChR-specific T helper (Th) cells. To define the repertoire of anti-AChR Th cells, we investigated the response of unselected blood CD4+ cells or total lymphocytes, or both, from 22 MG patients to 20-residue overlapping synthetic peptides, screening the complete sequence of human-muscle AChR alpha subunit. Several epitopes were identified. Only the most severely affected patients recognized alpha subunit epitopes, and they were mainly young women. Detection of in vitro AChR-specific CD4+ response was facilitated by removal of the CD8+ cells because in two patients a clear response to several alpha subunit peptide sequences could be detected when CD(8+)-depleted cells were used, while their total peripheral blood mononuclear cell population did not respond to any alpha subunit peptide. Although each patient had a unique pattern of peptide recognition, four immunodominant regions recognized by long-term AChR-specific CD4+ T-cell lines, or flanking peptide sequences, were recognized most frequently (residues 48-67, 101-137, 293-337, and 308-437).  相似文献   
58.
We treated 56 consecutive acute segmental femoral shaft fractures with closed static locked nailing. 12 nails were dynamized after 6 (5-10) months due to slow fracture healing and 5 united after another 5 (3-8) months. The other 7 required cancellous bone grafting and all healed uneventfully 6 (5-8) months after grafting. Since dynamization did not promote healing in most of our cases we suggest early cancellous bone grafting in cases of delayed union.  相似文献   
59.
When Chinese hamster ovary cells were treated with ultraviolet (UV) light or methyl methanesulfonate (MMS), a large number of DNA strand breaks could be detected by alkaline elution. These strand breaks gradually disappeared if the treated cells were allowed to recover in a drug-free medium. The presence of nickel or arsenite during the recovery incubation retarded the disappearance of UV-induced strand breaks, whereas the disappearance of MMS-induced strand breaks was retarded by the presence of arsenite or of luminol, a new inhibitor for poly(ADP-ribose) synthetase. Luminol, however, had no apparent effect on the repair of UV-induced DNA strand breaks, and nickel had no effect on the repair of MMS-induced DNA strand breaks. When UV- or MMS-treated cells were incubated in cytosine arabinofuranoside (AraC) plus hydroxyurea (HU), a large amount of low molecular weight DNA was detected by alkaline sucrose sedimentation. The molecular weight of these DNAs increased if the cells were further incubated in a drug-free medium. This rejoining of breaks in cells pretreated with UV plus AraC and HU was inhibited by nickel and by arsenite, but not by luminol. The rejoining of breaks in cells pretreated with MMS plus AraC and HU was inhibited by luminol and by arsenite, but not by nickel. These results suggest that different enzymes may be used in DNA resynthesis and/or ligation during the repairing of UV- and MMS-induced DNA strand breaks, and that nickel, luminol, and arsenite may have differential inhibitory effects on these enzymes. © 1994 Wiley-Liss, Inc.  相似文献   
60.
Cholinergically induced bronchoconstriction is thought to be a major cause of bronchospasm during anesthesia. We used tracheally intubated rabbits (4-mm endotracheal tube) stimulated with methacholine to assess the efficacy of beta-adrenergic agonist and anticholinergic treatment in reversing the increases in respiratory system resistance. Four groups were compared: (a) inhaled metaproterenol, 20 puffs via metered dose inhaler (0.65 mg/puff); (b) inhaled ipratropium bromide, 20 puffs from a metered dose inhaler (18 micrograms/puff); (c) 2 mg of intravenous atropine; and (d) no treatment after methacholine challenge as a control group. Methacholine increased respiratory system resistance from 0.041 +/- 0.001 (mean +/- SEM) to 0.098 +/- 0.006 cm H2O.mL-1.s-1 (P < 0.001). Whereas beta-adrenergic agonist treatment was ineffective in ameliorating bronchoconstriction, inhaled ipratropium bromide and atropine were highly effective, causing an 86%-88% reversal in the methacholine-induced increase in respiratory system resistance. Both these agents were also effective in improving dynamic compliance. We conclude that inhaled ipratropium bromide is effective in treating cholinergic bronchospasm even when administered via a small endotracheal tube and that the beta-adrenergic agonist metaproterenol is ineffective in rabbits in the face of maximal cholinergic stimulation.  相似文献   
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