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171.
172.
Two visual areas, V1 and V2 (first and second visual areas), appear to be present in the posterior neocortex of all eutherian mammals investigated so far. However, previous studies have not established whether an area homologous to V2 also exists in metatherian mammals (marsupials). Using electrophysiological techniques, we mapped the visual receptive fields of neurons in the striate and peristriate cortices of the northern quoll, an Australian marsupial. We found that neurons in a 2-mm-wide strip of cortex rostrolateral to V1 form a single, relatively simple representation of the complete contralateral hemifield. This area resembles V2 of eutherians in several respects: (i) neurons in the medial half of the peristriate area represent the lower visual quadrant, whereas those in the lateral half represent the upper visual quadrant; (ii) the vertical meridian of the visual field is represented adjacent to V1, while the visual field periphery is represented along the lateral and rostrolateral borders of the peristriate area; (iii) there is a marked anisotropy in the representation, with a larger magnification factor parallel to the V1 border than perpendicular to this border; and (iv) receptive fields of multiunit clusters in the peristriate cortex are much larger than those of cells in V1 at comparable eccentricities. The cortex immediately rostral and lateral to V2 did not respond to visual stimulation under our recording conditions. These results suggest that V1 and V2 together form a 'core' of homologous visual areas, likely to exist in all therian mammals.  相似文献   
173.
1. Cacospongionolide B is a novel marine metabolite isolated from the sponge Fasciospongia cavernosa. In in vitro studies, this compound inhibited phospholipase A2 (PLA2), showing selectivity for secretory PLA2 (sPLA2) versus cytosolic PLA2 (cPLA2), and its potency on the human synovial enzyme (group II) was similar to that of manoalide. 2. This activity was confirmed in vivo in the 8 h zymosan-injected rat air pouch, on the secretory enzyme accumulating in the pouch exudate. Cacospongionolide B, that is bioavailable when is given orally, reduced the elevated levels of sPLA2 present in paw homogenates of rats with adjuvant arthritis. 3. This marine metabolite showed topical anti-inflammatory activity on the mouse ear oedema induced by 12-O-tetradecanoylphorbol acetate (TPA) and decreased carrageenin paw oedema in mice after oral administration of 5, 10 or 20 mg kg(-1). 4. In the mouse air pouch injected with zymosan, cacospongionolide B administered into the pouch, induced a dose-dependent reduction in the levels of eicosanoids and tumour necrosis factor alpha (TNFalpha) in the exudates 4 h after the stimulus. It also had a weak effect on cell migration. 5. The inflammatory response of adjuvant arthritis was reduced by cacospongionolide B, which did not significantly affect eicosanoid levels in serum, paw or stomach homogenates and did not induce toxic effects. 6 Cacospongionolide B is a new inhibitor of sPLA2 in vitro and in vivo, with anti-inflammatory properties in acute and chronic inflammation. This marine metabolite was active after oral administration and able to modify TNFalpha levels, and may offer an interesting approach in the search for new anti-inflammatory agents.  相似文献   
174.
Trypsin inhibitors were purified from a saline extract of Bauhinia bauhinioides seeds by ion-exchange column chromatography on DEAE-Sephadex, gel filtration on Superose 12 column, Mono Q ion-exchange chromatography or, alternatively, by affinity chromatography on trypsin-Sepharose. Both B. bauhinioides isolated inhibitors, BbTI-I and BbTI-II, inhibit trypsin being the dissociation constant 0.6 and 0.36 nM, respectively. BbTI-II only inhibits porcine pancreatic kallikrein hydrolysis of H-Pro-Phe-Arg-AMC (Ki 2.0 nM); the bradykinin-containing sequence LGMISLMKRPPGFSPFRSSRI-NH2 and the two kininogen related flanking quenched substrates Abz-MISLMKRP-EDDnp (Ki 2.0 nM) and Abz-FRSSRQ-EDDnp (Ki 2.5 nM).  相似文献   
175.
Zusammenfassung Es wurde nachgewiesen, daß bei konkomitierender Esotropie außer sensorischen Folgen auch senso-motorische Folgezustände vorkommen. Sie lassen sich vor allem mit Prismen nachweisen und werden als fusionsbedingt aufgefaßt (anomale Fusionsbewegungen).Bei 30 Patienten wurden die Eigenschaften dieser Vorgänge untersucht und erklärt. Schließlich wurde der Zusammenhang zwischen den anomalen Fusionsbewegungen und schon früher von anderen Autoren beschriebenen Krankheitsbildern analysiert, die je nach der ihnen zugrundegelegten Auffassung, unter verschiedenen Namen bekannt waren.
Anomalous fusional movements: The sensorimotor aspect of anomalous binocular vision
Summary It has been demonstrated that, besides sensory adaptation phenomena, sensorimotor phenoma may also develop in concomitant esotropia. The existence of the latter entity can be shown particularly by means of prisms and is interpreted as fusional in origin. It is therefore defined as anomalous fusional movements.The features of these anomalous fusional movements were studied in a group of 30 patients, mainly in order to investigate their finality.Correlations were evaluated between anomalous fusional movements and entities previously described by different names according to the interpretation given them by various authors.
  相似文献   
176.
The effects of different doses of amphetamine (0-1.5 mg/kg) and apomorphine (0-1.0 mg/kg) on behaviour of pigs were compared. Amphetamine induced an increase in levels of nosing and rooting and of locomotion. These increases were, however, related to increased levels of standing. At higher doses (1.0-1.5 mg/kg), amphetamine specifically induced a rigid standing posture with jerking head and limb movements. Apomorphine at 0.1-1.0 mg/kg increased locomotion. In contrast to amphetamine, this effect was specific as it was not explained by increased levels of standing. At 1.0 mg/kg, apomorphine specifically induced "locomotion while the pigs maintained snout contact with the floor or trough." In addition, at this dose it induced drinking in one test, while licking in another. These differences may in part be due to differences in the test environment. Apomorphine exerted a strong conditioning effect, as indicated by the lack of behavioural variability in the postinjection period. This effect may explain the large interindividual variation in apomorphine response. Amphetamine and apomorphine elicit different behavioural syndromes in pigs, suggesting that they act on different neural systems. In addition, neither amphetamine nor apomorphine elicited behaviour that closely resembles environmentally induced stereotypies.  相似文献   
177.
In the last twenty years maternal mortality attributed to anaesthesia has decreased. Inhalation of gastric contents is the commonest cause in patients undergoing cesarean section; in fact pregnant women are considered "high risk" because of gravidic modifications. In this retrospective study of 10017 caesarean sections performed under general anaesthesia in our institution between January 1980 and December 1990, we evaluated the frequency of this syndrome (7 cases = 1:1431). We had no case of maternal and neonatal mortality. All these seven patients were admitted at our recovery room for less than 5 days; aspiration pneumonitis occurred in only three patients. Our results suggested that induction of anaesthesia with high doses of thiopental reduces complications related to light anaesthesia, including vomiting. At a dose of 5-6 mg/kg thiopental didn't produce any significant neonatal depression as documented by Apgar scores.  相似文献   
178.
Lyme disease can be confirmed in the laboratory by isolation or detection of its causative agent, a tick-borne spirochete Borrelia burgdorferi, or by a diagnostic change in the titre of antibodies specific to the agent. B burgdorferi can be isolated and cultivated in Barbour-Stoenner-Kelly II medium. It can be detected by light microscopy in tissue sections or, rarely, in blood smears using various staining methods. There is interest in the development of alternative detection methods, including identification of specific antigens of B burgdorferi in the urine of suspected cases and demonstration of the presence of species-specific DNA using polymerase chain reaction assays. Currently, serological tests (indirect immunofluorescence assay, enzyme-linked immunosorbent assay and Western immunoblot) are the most practical and available methods for confirming Lyme disease. The quest to improve the specificity and sensitivity of serological tests - for example, through the use of specific recombinant antigens - continues.  相似文献   
179.
OBJECTIVE: To evaluate whether the survival of patients with Parkinson disease (PD) is shorter than that of the general population. DESIGN: Survival was investigated in a cohort of patients with PD previously identified during a population-based prevalence study (prevalence day, November 1, 1987, reference follow-up date, October 31, 1995). The survival of patients with PD was compared with that of a control sample randomly selected from the same population (2 controls for each case, matched for age, sex, and study municipality). The causes of death in the 2 groups were also compared. Both univariate and multivariate survival analyses were performed to investigate the association with disease-related variables. SETTING: A door-to-door 2-phase prevalence survey performed in 3 Sicilian municipalities. PATIENTS: Fifty-nine patients with PD and 118 controls. RESULTS: Patients with PD showed a high risk of death (relative risk, 2.3; 95% confidence interval, 1.60-3.39). Greater age at November 1, 1987, high Hoehn-Yahr score, and lack of levodopa therapy were associated with a lower survival on univariate analysis. Multivariate analysis confirmed the association between shorter survival among patients with PD and greater age on November 1, 1987. One-way analysis of variance indicated a different effect of levodopa therapy according to age. Multivariate analysis did not confirm this finding. Pneumonia was the cause of death most frequently associated with PD. CONCLUSION: This study indicates that patients with PD have a shorter survival time than the general population.  相似文献   
180.
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