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991.
T Kono S Taniguchi N Mizuno M Fukuda N Maekawa T Hisa M Ishii S Otani T Hamada 《The Journal of dermatology》1992,19(7):389-392
The effects of butylated hydroxyanisole (BHA), a representative phenolic antioxidant, on the activity of ornithine decarboxylase (ODC, an indicator of tumor promotion and epidermal hyperproliferation) induced by ultraviolet-B (UVB) or PUVA in mouse skin were investigated. By topical application of BHA (55 mumol), PUVA-induced ODC activity was suppressed by about 60% at both 12 h and 24 h after treatment. In contrast, BHA failed to suppress UVB-induced ODC activity in mouse skin. These results suggest that the induction of ODC activity by UVB or PUVA is mediated by different pathways. 相似文献
992.
Physiological and morphological characteristics of cat masticatory motoneurons--intracellular injection of HRP 总被引:1,自引:0,他引:1
The physiology and morphology of masticatory motoneurons of adult cats were examined by the methods of intracellular recording and intracellular injection of horseradish peroxidase. Masseter and jaw-opening motoneurons were identified by intracellular recordings of the antidromic response following stimulation of the masseter and mylohyoid nerves, respectively. An excitatory postsynaptic potential (EPSP) was recorded from masseter neurons by stimulation of the masseter nerve with stimulus intensity below threshold for antidromic response. In contrast, the EPSP was not recorded from jaw-opening motoneurons by stimulation of the mylohyoid nerve with stimulus intensity below threshold for antidromic response. Patterns of postsynaptic potentials (PSPs) in the masseter motoneurons following stimulation of the tooth pulp or periodontal afferents were classified into 4 types: hyperpolarization (n = 40), depolarization-hyperpolarization (n = 9), hyperpolarization-depolarization (n = 5), and depolarization with spike potentials (n = 10). On the other hand, patterns of the PSPs in the jaw-opening motoneurons following stimulation of the same afferents were classified into two types: depolarization with spike potentials (n = 19), and hyperpolarization (n = 5). Twenty-five masseter and 7 jaw-opening motoneurons and an intranuclear neuron were reconstructed from serial sections in the transverse plane. On the basis of dendritic morphology, the masseter motoneurons could be classified into two major groups, type I (n = 15) and type II (n = 9), whereas two neurons were found to constitute a separate category of the masseter motoneuron. The dendritic distributions of all the jaw-opening motoneurons examined were generally similar and there was no indication of the existence of subtypes, whereas there were 2 or 3 subgroups in type I and type II masseter motoneurons. Type I masseter neurons had primary dendrites which extended radially in all directions, and the whole profile of their dendritic trees presented a spherical and an egg-shaped appearance. In type II masseter neurons, the origin of primary dendrites was bipolar or tripolar, and the whole profile of their dendritic trees presented a hemispherical and mirror-imaged, funnel-shaped appearance. The other two masseter motoneurons had a particular dendritic tree which was much simpler in configuration, with less tapering or branching than those of other neurons examined. In contrast, the dendritic profiles of all the jaw-opening motoneurons were similarly organized and showed vertically oriented dendritic trees which were more developed in the dorsomedial than in the ventrolateral direction.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
993.
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995.
MAIN PROBLEM: Nucleus pulposus and/or chronic compression can induce spinal nerve root injury. Inflammation has been proposed as having major importance in the pathophysiologic mechanisms involved in the induction of such injuries. Corticosteroids, potent anti-inflammatory drugs, have been demonstrated to reduce nucleus pulposus-induced spinal nerve root injury. The aim of the present study was to assess the effects of two potent non-steroidal anti-inflammatory drugs (NSAIDs), diclofenac and ketoprofen, in experimental nucleus pulposus-induced spinal nerve root injury in a pig model. METHODS: Eighteen pigs were included in the study. Autologous nucleus pulposus was harvested from a lumbar disc and applied locally around the first sacral nerve root after a partial laminectomy of the first and second sacral vertebrae. Six pigs were treated with daily intramuscular injections of diclofenac, 3 mg/kg body weight, for 7 days. Six other pigs were treated with daily intramuscular injections of ketoprofen, 4 mg/kg body weight, for 7 days. As controls, six pigs received injections with physiologic saline. After 7 days, the pigs were reanesthetized and the nerve conduction velocity over the exposed nerve root area was determined. RESULTS: The nerve conduction velocity was significantly higher in pigs treated with diclofenac than in the saline-treated controls, (57 +/- 6 m/s vs 38 +/- 18 m/s, P<0.05, Student's t-test). The velocity in pigs treated with ketoprofen, 42 +/- 24 m/s, did not differ significantly from that of controls. CONCLUSIONS: This study of two potent NSAIDs indicates that nucleus pulposus-induced nerve root dysfunction may be reduced by diclofenac but not by ketoprofen. The reason for this difference is not known, but it might be related to the fact that ketoprofen and diclofenac belong to different NSAID subgroups and have a different selectivity for the two cyclo-oxygenases COX-1 and COX-2. 相似文献
996.
Summary The nervous system and small intestine of mice infected with herpes simplex virus were examined by electron microscopy from the viewpoint of virus-host interaction.The host cells examined included the neuron, astrocyte, oligodendrocyte, and Schwann cell. The susceptibility of the latter was not less than that of the neuron. The endothelial cell, perineural fibrocyte and smooth muscle cell were also host cells. Replication of herpes virus in the nervous system was proven to be identical to that occurringin vitro; initial reproduction of nucleocapsids in the nucleus and subsequent maturation at the nuclear membrane with envelope formation, followed by discharge into the cytoplasmic reticular cavities and finally release from the host cell. Inconsistency in the distribution of virus particles and viral antigen was chiefly concerned with the host cell nucleus and the glial cytoplasm.Herpes virions, though few, were identified in the axons of peripheral nerves, and in the periaxonal space of myelinated fibres in the brain and the nerve ganglia. Virions were present in tiny vesicles in the perikarya or as naked particles. In the distal parts of peripheral nerve, there was marked dissociation in the amount of virions between Schwann cells and the axon. The significance of the endoneural space and the axon in the neural speread of infection is discussed briefly. 相似文献
997.
The differences in the velocity and pulsatility indexes in the internal carotid artery were evaluated in 62 normal controls, 42 infants with cerebral palsy, and 22 infants with mental retardation, all within the first year of life. In the normal controls, the average maximal blood flow velocity (A/L), and the maximal end-diastolic flow velocity increased during the first year of life. Pulsatility index decreased significantly between the ages of newborn to 2 mos and 3-5 mos, and remained constant thereafter. Compared with normal controls, the average maximal blood flow velocity and the maximal end-diastolic flow velocity values were significantly reduced in infants with cerebral palsy during the first 6 months of life, while no differences in these values were observed in infants with mental retardation. There were no differences in the pulsatility index values in the 3 subject groups throughout the first year of life. Flow velocity in the internal carotid artery could reflect the status of the cerebral circulation in infants within the first year of life. 相似文献
998.
I Sakashita S Otani M Terashima A Eguchi C Nakamura 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1979,27(11):1537-1543
999.
Six healthy male subjects were randomly given nortriptyline (NT) (25 and 50 mg) and placebo in a double-blind, crossover study. An NT dose of 50 mg (but not 25 mg) clearly reduced saliva flow (P less than 0.05) and was therefore used for comparison with the major and active metabolite of NT, E-10-hydroxynortriptyline (E-10-OH-NT). Equimolar doses of both compounds (and placebo) were randomly given to eight healthy male subjects in another double-blind, crossover study aimed to assess the reduction of saliva flow. NT significantly depressed saliva flow compared with both placebo (P less than 0.01) and E-10-OH-NT (P less than 0.05). By contrast, there was no difference between E-10-OH-NT and placebo. This study confirms previous indications that the anticholinergic effect of E-10-OH-NT is considerably less than that of the parent drug NT. 相似文献
1000.
Shunsuke Endo Hiroyoshi Tsubochi Kenji Tetsuka Yukio Sato Tsuyoshi Hasegawa Shinichi Otani Noriko Saito Yasunori Sohara 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2006,54(3):109-113
Objectives: Survival benefits with preoperative chemotherapy for non-small cell lung cancer (NSCLC) remain controversial. Preoperative
chemotherapy may act on micrometastasis but not lymph node metastasis. To clarify the role of induction chemotherapy for control
of micrometastasis, we reviewed and compared 5-year follow-ups of clinical stage III but pathologically-proven node-negative
NSCLC patients after complete resection with or without preoperative chemotherapy. Methods: We reviewed 148 consecutive patients who underwent anatomical lung resection and mediastinal nodal dissection for pathologically-proven
node-negative NSCLC at our hospital between 1994 and 1999. Fifty-six patients were preoperatively diagnosed as stage III:
26 received platinum-based chemotherapy prior to surgery (PCT group) and 30 underwent surgery without any prior chemotherapy
(PRS group). Results: The 5-year survival rate for clinical stage I/II and pathological node-negative patients was 74.9%; for clinical stage III,
but for pathological node-negative patients it was 92.3% in the PCT and 63.3% in the PRS groups. The survival benefit of preoperative
chemotherapy was significant for clinical stage III patients without node involvement. Conclusion: Preoperative chemotherapy may provide survival benefits for node-negative NSCLC patients. 相似文献