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61.
Gastric motility in patients with recurrent gastric ulcers.   总被引:3,自引:0,他引:3  
The existence of abnormal gastric motility in gastric ulcer disease remains controversial. The aim of this study was to characterize gastric motility in patients with recurrent gastric ulcers. Studies were performed in 10 control subjects and in 24 patients with recurrent active gastric ulcer disease as diagnosed by gastrointestinal endoscopy. Gastric motility was evaluated by cutaneous electrogastrography (EGG) and by gastric semi-liquid meal emptying. The EGG was recorded before and after ingestion of a test meal containing 20 mg/kg of acetaminophen. Patients with a dominant EGG frequency of greater than 0.06 Hz were defined as tachygastria, while those with a frequency of less than 0.04 Hz were defined as bradygastria. A transient frequency decrease, called postprandial dip (PD), was identified visually. The degree of gastric emptying was determined from the serum acetaminophen concentration 45 minutes after the meal. Control subjects showed no irregularity in their dominant EGG frequency in tither fasting or postprandial states. PD was observed in 8 control subjects. In patients presenting with active gastric ulcers, abnormal patterns in the dominant EGG frequency (either as tachygastria or bradygastria) were observed in 14 of the 24 patients when fasting and in 15 of them in the postprandial state. After successful treatment, the number of patients with abnormal patterns in their dominant EGG frequency remained unchanged, while PD was observed in 11 patients. No significant difference was observed in the EGG power ratio as a result of successful treatment. Gastric emptying was significantly delayed compared with controls in both the active and healed stages. These findings suggest that abnormal gastric motility, including gastric electrical abnormalities and delayed gastric emptying, plays an important role in the pathophysiology of recurrent gastric ulcers.  相似文献   
62.
Early onset familial Alzheimer's disease with spastic paraparesis (FAD-SP) has been associated with mutations of the presenilin 1 gene (PSEN1). We report a pedigree of FAD-SP due to a novel missense mutation of PSEN1 (Y154N). The symptoms of the proband were characterized by presenile dementia in her 40s, preceded by spastic paraparesis in her 30s, whereas the mother of the proband presented with spastic paraparesis in her 40s, followed by symptoms of dementia in her mid 60s. The mutation was found only in the proband, and not in a normal family member, normal Japanese control subjects, patients with sporadic Alzheimer's disease or patients with familial spastic paraparesis without dementia. Thus, Y154N is a novel PSEN1 mutation responsible for FAD-SP of Japanese origin.  相似文献   
63.
Electrical stimulation in the mesencephalic central gray (CG) and adjacent subtectum through chronically implanted electrodes in free-moving estrogen-primed ovariectomized female rats elicited a rapid and large facilitation of the lordosis reflex in response to either male mounts or manula cutaneous stimuli. Unilateral stimulation was sufficient for this effect. The facilitation increased in a graded manner to increased stimulus intensity, and was optimally evoked by stimuli delivered at 50--150 Hz. Facilitation disappeared rapidly following the end ot electrical stimulation, and within 15 min, reflex performance returned to the prestimulation level. Lordosis facilitation appeared when no aversive responses occurred; stimulation with comparable parameters at the lateral edge of CG or in the mesencephalic reticular formation often resulted in postural changes or aversive responses but was not able to facilitate lordosis. Lordosis refelx facilitation was probably mediated by projections descending from neurons in and around the CG, and represents stimulation of a functional link between ascending somatosensory and descending motor systems for the control of lordosis behavior.  相似文献   
64.
We identified a new common amino acid polymorphism of isoleucine/valine at codon 796 in exon 16 of the gene for human sterol regulatory element binding protein (SREBP) cleavage-activating protein (SCAP), a central regulator of lipid synthesis and metabolism in animal cells. It can be detected as an MslI restriction fragment length polymorphism. The allelic frequencies were: isoleucine (A) allele, 0.57 and valine (G) allele, 0.43. This polymorphism may be useful for genetic studies of disorders affecting intracellular lipid metabolism and hyperlipidemia. Received: August 17, 1999 / Accepted: August 19, 1999  相似文献   
65.
In an attempt to clarify the cytological characteristics of the RES cells in the lymph nodes and their embryological correlations, lymph nodes and lymph node anlages of germ-free rats, nude mice, and human fetuses were light and electron microscopically examined. On the basis of differences of intracellular organelles, their behaviors for reticulum fibers and of endogenous peroxidatic activity, histiocytes should be reasonably distinguished from the cells conventionally called reticulum cells. Reticulum cells and histiocytes respectively are destined to differentiate in different directions from the early stage of development of the lymph node anlage. Sinus endothelial cells are ontogenetically originated and differentiated from the endothelial lining cells of lymphatic vessels. Primitive reticular cells are differentiated into mature reticulum cells in the lymph nodes, they transform into the lympho-reticular cells, further into lymphoblasts, and finally develop into medium-sized lymphocytes.  相似文献   
66.
The M-CSF and its receptor (M-CSFR, CSF-1R or c-fms proto-oncogene) system were initially implicated as essential in mammals for normal monocyte development as well as for pregnancy. To allow a comparison with the M-CSF and M-CSFR system of an oviparous animal, we cloned a M-CSFR-like gene from rainbow trout (Oncorhynchus mykiss). The gene was cloned from a cDNA library of head kidney. It contained an open reading frame encoding 967 amino acids with a predicted size of 109 kDa. The putative amino acid sequence of rainbow trout M-CSFR showed 54% amino acid identity to fugu (Takifugu rubripes) M-CSFR, 52% to zebrafish (Danio rerio) M-CSFR and 40% to mouse (Mus musculus) and human (Homo sapiens) M-CSFR. The M-CSFR-like gene was constitutively expressed in head kidney, kidney, intestine, spleen and blood. The gene was detected especially in the ovary of immature female rainbow trout. These results suggest that a M-CSFR-like receptor may be involved in female reproductive tracts even in an oviparous animal like fish.  相似文献   
67.
Twin and family studies had shown that genetic factors are important determinants of bone mass. Multiple genes might be involved. One candidate gene, the reversion-induced LIM gene (RIL), is a PDZ and LIM-domain-containing protein and has been localized within the cytokine cluster of chromosome 5 (5q31.1). In a genetic study of 370 adult Japanese women, we investigated the correlation between radial bone mineral density (BMD) and a genetic variation (−3333T→C) of the 5'-flanking region of RIL gene. A significant association was identified between the RIL variation −3333T→C and radial BMD (r=0.15, P=0.003). The variation of the RIL locus may be an important determinant of osteoporosis.  相似文献   
68.
Antidromic action potentials were recorded in and around the ventromedial nucleus of the hypothalamus (VMN) of the ovariectomized female rat following stimulation of the central gray matter of the mesencephalon (CG). The animals had either the lateral or caudal trajectory of the VMN efferent disrupted by a small knife cut. Changes in the polarity, peak-to-peak amplitude, and the duration of the initial positive deflection of the antidromic action potentials were recorded for each response as the recording electrode was advanced at 10-micron intervals from the point of detection of the potential until its deterioration. Seventy-four recordings in which potentials exceeded 2 mV at the maxima were subjected to further analysis. The mean spatial spread of the extracellular antidromic action potentials, which was measured by moving the recording electrode at 10-micron intervals, was significantly larger in responses in 17 animals bearing the posterior knife cut (n = 41) than those in 15 animals with the lateral knife cut (n = 33). Mean peak-to-peak amplitude was also significantly greater in responses from the posterior-cut animals than in those from the lateral-cut ones. In the former, action potentials were completed with a shorter time lapse than the latter. In the posterior-cut animals, estrogen treatment of the ovariectomized rats significantly lowered antidromic activation thresholds and shortened absolute refractory periods for CG stimulation. Estrogen had no detectable effect on the excitability of cells that survived the lateral cut. Histological analyses located antidromically driven cells in the posterior-cut animals in the rostral extremity of the VMN and the adjacent retrochiasmatic area; those in the lateral-cut animals were scattered in and around the VMN, caudad to the former. These results suggest that rostral VMN neurons with large soma and laterally projecting axons are responsible for estrogen-dependent autonomic, neuroendocrine, and behavioral functions, such as reproduction and feeding.  相似文献   
69.
BACKGROUND: FK506 ointment (tacrolimus ointment, protopic) is a new drug therapeutically effective for patients with atopic dermatitis (AD). However, the mechanism of action of FK506 ointment on AD is not fully understood. METHODS: We examined the effect of FK506 ointment on mite antigen-induced dermatitis in NC/Nga mice. Clinical symptoms and ear thickness were recorded, and histopathological studies and in vitro analyses were performed. RESULTS: Topical application of FK506 ointment (0.03-0.3%) suppressed the development of dermatitis. In the lesional skin, both interleukin (IL)-4 and interferon (IFN)-gamma were detected, even though the IL-4+/IFN-gamma- T helper 2 (Th2) population was predominant in the regional lymph nodes (LNs). Topical application of FK506 treatment reduced the elevated level of both IL-4 and IFN-gamma in the skin, but did not decrease the expansion of the Th2 population in the LNs. CONCLUSIONS: Topical application of FK506 ointment suppresses dermatitis by inhibiting the activation of inflammatory cells locally, without systemic immune suppression, in this AD model.  相似文献   
70.
Vinylogous nucleophilic substitution polymerization of 2,5-dihydroxy-p-benzoquinone and 2,5-dimethoxy-p-benzoquinone with various diamines in m-cresol afforded polyaminoquinones with inherent viscosities as high as 0,5 dl.g?1 in quantitative yields. The polyaminoquinones, except for the polymer derived from 1,3-bis(aminomethyl)benzene, were partially soluble or practically insoluble in organic solvents, but were solubilized by alkaline hydrosulfite reduction. Thermal analyses showed an initial weight loss at around 200°C in both air and nitrogen atmospheres, followed by gradual decomposition.  相似文献   
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