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101.
PAF-likely activity, detected as aggregation of washed platelets, was found in the exudate of rats with pleurisy induced by phorbol myristate acetate (PMA, 1 nmol). At 30 min after the injection of PMA, 400-500 pg of PAF was detected in the pleural exudate. An extract of the exudate was made and analysed by HPLC and by rabbit platelet aggregation. The activity was characterized as that of PAF as a result of the inhibition seen with the PAF-antagonist CV-3988 and the loss of activity by treatment with phospholipase A2. Indirect evidence was previously reported in that CV-3988 suppressed the pleural fluid accumulation in the pleurisy induced by PMA. Taken together these facts it indicates that PAF could be an important mediator of acute inflammation, especially of the plasma exudation resulting from an increase in vascular permeability. Evidence that pleural cells produce PAF was also examined in an in vitro experiment. PAF was found in the supernatant and cellular fractions of the incubation mixture of the pleural cells from normal rats when stimulated by PMA (1 microM) or A23187 (5 microM), and the results indicate that the pleural cells produce PAF and release a portion of it.  相似文献   
102.
Immunostaining patterns of two glia-associated proteins, glial fibrillary acidic protein (GFAP) and S-100 protein (S100P), were compared using the peroxidase-antiperoxidase (PAP) method on adjacent paraffin sections in 100 brain tumors including 52 astroglial tumors, 13 oligodendrogliomas, 14 ependymomas, 13 choroid plexus papillomas and 8 medulloblastomas. Most astroglial tumors showed similar immunoreactivity for both proteins. Fibrillary processes, however, showed a stronger and more crisp staining with anti-GFAP than with anti-S100P, whereas cell nuclei were labeled only for S100P. Focal dissociation of immunoreactivities for the two proteins was prominent in several malignant astroglial tumors including giant cell glioblastoma, and in subependymal giant cell astrocytoma. In oligodendrogliomas, GFAP-positive neoplastic oligodendrocytes also showed immunoreactivity for S100P; a smaller number of tumor cells were immunoreactive only for S100P, comparable to normal mature oligodendroglia. Most ependymomas were characterized by a similar distribution of cells immunoreactive for both proteins. In choroid plexus papilloma, absent or only focal immunoreactivity for GFAP contrasted with diffuse labeling for S100P in all cases; this seems of value for a differential diagnosis of papillary CNS tumors. In medulloblastoma, some tumor cells of a classical type were immunoreactive only for S100P; on the contrary, GFAP positive tumor cells with sparse or absent immunoreactivity for S100P were found in desmoplastic medulloblastomas. Similar immunoreactivities for both proteins in most tumors suggest a generally parallel production of both proteins by glial tumor cells.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
103.
104.
Recent DNA studies performed by several groups have detected mutations of the gene encoding fibroblast growth factor receptor 3 (FGFR3) in patients with achondroplasia-group disorders, including achondroplasia (ACH), hypochondroplasia (HCH), and thanatophoric dysplasia (TD). For this study, we analyzed theFGFR3 gene in 31 Japanese patients with typical ACH, four with HCH, three with a condition intermediate between ACH and HCH (ACH/HCH-intermediate), and one with TD. Of the 31 typical ACH patients, 29 showed a G1138 to A transition and the other two a G1138 to C transversion, both resulting in a common Gly380Arg substitution in the transmembrane domain of FGFR3. The one TD and the four HCH patients did not display any mutations in the transmembrane domain of FGFR3. Of the three ACH/HCH-intermediate cases, one patient showed the Gly380Arg substitution and one did not, and further analysis of the second patient revealed the presence of Asn540Lys substitution. The first patient was, therefore, genotypically diagnosed as ACH and the second as HCH. Peripheral blood leukocyte DNA analysis in the remaining ACH/HCH-intermediate patient indicated an unequal ratio of mutant to normal PCR products, possibly representing a somatic mosaic for the Gly380Arg mutation. Analysis of the common FGFR3 mutation thus appears to help in the molecular diagnosis of patients with achondroplasia-group disorders.  相似文献   
105.
It has been recently reported that acute immobilization stress almost completely suppresses the luteinizing hormone (LH) release induced by naloxone, a μ-opioid antagonist, in ovariectomized estrogen-primed rats. The present study examined the possible involvement of the pineal gland in the acute immobilization-related suppression of the naloxone-induced LH release. An intraventricular (ICV) injection of 15 μg naloxone produced an abrupt increase in circulating LH concentrations in non-stressed rats. The naloxone-induced LH release was completely eliminated when tested 60 min after the end of a 30 min session of acute immobilization. The same stress conditions did not affect LH-releasing hormone (LHRH)-induced LH release, suggesting that the stress-related suppression of the naloxone-induced LH release was a suprapituitary event. In chronically-pinealectomized rats, but not in sham-pinealectomized rats, naloxone injected 60 min after the end of the stress session evoked a significant increase in serum LH concentrations. However, naloxone injected ICV during the acute immobilization did not elicit LH release in either pinealectomized or sham-operated rats. Under non-stressed conditions, the LH secretory response to naloxone was similar in pinealectomized and sham-operated animals. The same stress (30 min immobilization) significantly increased pineal melatonin content as well as plasma melatonin concentrations in rats bearing intact pineal glands, indicating that stress actually affected the pineal function. These results provide evidence for a role of the pineal in the suppression of the LH response to naloxone after stress, but not during stress.  相似文献   
106.
The effects of long-term glucocorticoid therapy on airway inflammation were examined in 84 asthma patients. The proportion of lymphocytes in bronchoalveolar lavage (BAL) fluid was significantly decreased in patients with steroid-dependent intractable asthma (SDIA) compared to results in non-SDIA patients, while BAL neutrophils were significantly increased in SDIA patients compared to results in non-SDIA patients. Regarding age, in patients under the age of 69 (except those between 30 and 39), BAL lymphocyte number was significantly decreased in SDIA compared with non-SDIA subjects, and in patients between 50 and 69, BAL neutrophils were significantly increased in SDIA compared with non-SDIA subjects. The number of BAL lymphocytes was significantly lower in patients with serum cortisol levels of less than 5.0 μg/dl than in those with levels of more than 5.1 μg/dl. BAL lymphocyte number was also significantly lower in patients who had received glucocorticoid therapy for more than 6 years than in those who had received such therapy for 2 years. These results show that long-term glucocorticoid therapy decreases the number of lymphocytes and increases neutrophil numbers in the airways.  相似文献   
107.
Lacunes on brain MRI, causal blood pressure, 24-hour ambulatory blood pressure and common carotid blood flow measured by the doppler method were studied in 31 elderly patients with Parkinson's disease (mean age 67.5 +/- 7.3 years). Nineteen patients with Parkinson's disease (61%) had at least one lacune. Patients with lacunes (P(+)) were significantly higher in age than patients without lacune (P(-)). The difference of casual blood pressure between patients in the two groups was not significant. On the other hand, the average of ambulatory blood pressure measurements during a 24-hour period was significantly higher in the P(+) group than in the P(-) group. The average of carotid blood flow was also significantly lower in the P(+) group than in the P(-) group, however, after adjustment for age, the difference between them became insignificant. In conclusion, the incidence of silent lacunes on brain MRI was fairly common in elderly patients with Parkinson's disease. A high average 24-hour ambulatory blood pressure was suggested to be one of the risk factors of lacunar stroke in elderly cases of Parkinson's disease. The concept of "combine type" in Parkinsonism was supposed to be suitable as well as in senile dementia of Alzheimer type.  相似文献   
108.
Visual analogue scale of happiness (VAS-H) was applied to elderly Himalayan highlanders to investigate the influence of life-style and socio-cultural background on subjective happiness. The score of "VAS-H" and neuropsychological function tests in 733 Himalayan highlanders who belonged to 5 separate villages were compared with those in 313 Japanese elderly subjects. The places of study consisted of 4 villages (Khalimabad; K, Gulmit; G, Pasu; P, Shimshal; S) in Hunza area in Pakistan, and Namche Bazar; N in Nepal. Degree of modern civilization was highest in K, followed by N, G, P and lowest was that in S by historical and sociological aspects. The mean VAS-H sore in Himalayan highlanders and the degree of modern civilization in the area was in inverse proportion. Himalayan elderly women showed a significant lower score on VAS-H compared with elderly Himalayan men or elderly Japanese subjects. The VAS-H score in the Japanese elderly correlated significantly with the stability of posture and walk, and that of Himalayan highlanders correlated significantly with manual skill. In conclusion, the life style or socio-cultural background strongly affected subjective happiness in the elderly. The VAS-H was useful in comparing subjective happiness in different cultures.  相似文献   
109.
Right-hand superiority for throwing but not for intercepting   总被引:2,自引:0,他引:2  
N V Watson  D Kimura 《Neuropsychologia》1989,27(11-12):1399-1414
In humans, the organization of movements performed by both upper limbs, relies significantly on a left hemisphere "praxis" system that also subsumes speech function. Right hand preference may also be an expression of this left hemisphere dependence, arising from the preferential connections of the right hand to the left hemisphere. Consequently, a manual task that maximizes the spatial complexity of a target (presumably engaging right hemisphere mechanisms), while concurrently minimizing motor-programming demands, was expected to yield a diminished disparity in preference and performance between the hands. Left and right hand accuracy were measured independently for two motor tasks in 48 normal right-handed university students. In the first task, darts were thrown overhand at a stationary target. For the second task, subjects were asked to use the open hand to block (but not catch) projectiles launched at varying trajectories and velocities. ANOVA yielded a significant Hand x Task interaction, in which the left hand did not differ from the right hand in intercepting ability, but was significantly less accurate than the right hand for throwing. A sex difference favouring males was found for both tasks; this difference was not reducible to differences in physique or athleticism.  相似文献   
110.
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