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101.
Background: Our epidemiological study demonstrates the spontaneous long-term course of predominantly psychosocially influenced (“psychogenic”) disorders (neurotic spectrum disorders, personality disorders, stress reactions and somatoform disorders) in a representative community sample of the normal adult population of Mannheim, an industrial and university town in Germany. The natural spontaneous course of these disorders in a population sample over a long period remains largely unknown. Method: Beginning in 1979 (n t1 = 600) a random population sample was investigated three times over a mean period of approximately 11 years. The last follow-up study ended in 1994 (n t3 = 301). The follow-up sample was representative of the t1 sample. Psychodynamically trained and clinically experienced interviewers used a semi-structured interview and standardized clinical and psychometric instruments. Psychogenic impairment was assessed using a standardized expert rating (Impairment Score, IS). Results: The mean sum-score of psychogenic impairment after 11 years exceeded the value at t1. The case rate (point prevalence, ICD diagnosis + clinical cut-off/IS) increased from 21.6% at t1 to 26.2% at t3 in the investigated follow-up sample. Intra-individual correlation of psychogenic impairment between t1 and t3 was high (r = 0.55). We found strong evidence for an unfavorable long-term course of psychogenic impairment and only a weak tendency (23.1%) for spontaneous remission of clinically relevant psychogenic impairment. Within a regression model clinical variables, childhood development conditions and personality traits at t1 predicted psychogenic impairment at t3. Conclusion: All clinical variables conclusively indicate an unfavorable spontaneous long-term course of psychogenic impairment. Together with the well-known high prevalence of psychogenic disorders in the normal population, this underlines the need for early therapeutic and preventive intervention. Accepted: 20 August 1999  相似文献   
102.
Neuropsychological performance, magnetic resonance imaging (MRI) and electroencephalography (EEG) were investigated in 12 consecutive patients with very mild traumatic brain injury (MTBI) (Glasgow coma score 15) within 24 hours and 6 weeks after injury. The data were compared to 14 control subjects. There was a significant impairment in neuropsychological performance (verbal memory, arithmetic abilities and psychomotor reaction time) at onset and after 6 weeks, whereas verbal fluency and non-verbal memory test revealed no significant differences matching the control values. In MRI scans, three patients showed traumatic lesions (slight epidural haematoma, haemorrhagic contusions and white matter lesions indicating diffuse axonal injury). In the EEG recordings, no generalized slowing or focal changes were found. Structural and functional impairment can be identified using neuroimaging and neuropsychological examination, even in very MTBI patients.  相似文献   
103.
Recent clinical observations indicate that female gender is associated with a higher risk of developing torsades de pointes (TdP) cardiac arrhythmia. In this study, we used the Langendorff technique in isolated perfused rabbit hearts and the whole-cell patch-clamp technique in ventricular myocytes to examine the gender difference in TdP incidence and gain insight into the underlying mechanisms. Isolated rabbit hearts were perfused by using the Langendorff technique. TdP was induced by abrupt changes of cycle length (deltaCL) in the presence of Tyrode's solution containing 1 mM 4-aminopyridine (4AP) and 50% reduced Mg2+ and K+ (low K/Mg). The effects of 1 mM 4AP on cardiac potassium currents were characterized by using the patch-clamp technique. Results demonstrated that (a) no significant gender difference was observed in the absolute QT interval before or after 4AP perfusion in the presence of low K/Mg; (b) 4AP caused marked QT prolongation in the ECG; (c) a significantly higher TdP incidence (nine of 12) was found in female hearts compared with male hearts (three of 12; p < 0.05); (d) 1 mM 4AP primarily inhibited Ito, although a slight inhibition of IKr also occurred in low-K/Mg Tyrode's solution. (e) No inhibition of IK1 was observed. (f) No gender difference was found in the potassium current block produced by 4AP. Female gender is associated with a higher incidence of TdP in an experimental isolated heart model and mechanisms subsequent to QT prolongation may contribute to such a gender difference.  相似文献   
104.
Single-channel measurements were performed with the aim of constructing a detailed molecular scheme for the reaction between -aminobutyric acid (GABA) and a chloride channel of crayfish deep extensor abdominal muscle (DEAM). GABA was applied in pulses to outside-out patches of muscle membrane, and, based on the dose-response of the peak currents and of their rise times, a linear model with five binding steps has been proposed. Evaluation of the single-channel kinetics indicated at least three open states. Two of them originate most probably from the fully liganded receptor state and are grouped in mixed bursts due to their different life times. The third one appears independently, outside the bursts, and originates from a lower liganded receptor state. Simulations of the dose-responses and the open time distributions with this model led to a set of rate constants which generated relatively optimal fits.  相似文献   
105.
Twenty-five healthy infants were followed from the newborn period to the age of eighteen months, by evaluation of their neuromotor performance. Evaluation of the specific postural reaction patterns (as described by Vojta) did not seem to be any use as a "short-cut" for the early diagnosis of neuromotor abnormalities, a considerable number of deviations from the normal/optimal pattern being noted even in completely normal infants.  相似文献   
106.
107.
Kram G  Franz G 《Planta medica》1983,49(11):149-153
Linden flowers are known to contain considerable amounts of mucilage. Quantitative determinations of these water soluble polysaccharides were carried out by viscosimetric measurements. It was shown that the mucilage after total hydrolysis in trifluoracetic acid was composed of D-galactose, L-arabinose and L-rhamnose and minor amounts of D-glucose, D-mannose and D-xylose. The high percentage of uronic acid (52%) was due to the presence of both, D-galacturonic acid and D-glucuronic acid. Fractionation of the mucilage polysaccharides on DEAE-cellulose resulted in a separation of five distinct polysaccharide fractions, which showed different sugar compositions and uronic acid content. The homogeneity of the polysaccharide fractions 1-5 was further examined by high voltage electrophoresis and analytical ultracentrifugation.  相似文献   
108.
Haemostasis was effected in vessels of melanin-rich (MR: choroid) and melanin-free (MF: mesentery) rabbit tissue irradiated with a cw-Nd: YAG laser. The following parameters were employed: - pulse duration: 200 ms (MR) and 100ms (MF); focal spot diameter: 200 m (MR) and 80 m (MF); pulse energies: 100–250 mJ (MR) and 0.5-1J (MF); irradiances: 1.6–4.0kWcm–2 (MR) and 1–2 × 102kWcm2 (MF). In melanin-rich tissue, laser energy is absorbed principally by melanin granules contained within the stromal melanocytes. The heat generated in these structures radiates into the surrounding tissue where it is dissipated. The damage thus incurred by the endothelium of blood vessels encompassed within this field triggers the haemostatic mechanism whereby blood flow is arrested. This effect is realized by the formation of an occluding plug of platelets, which is stabilized by the deposition of fibrin, particularly in capillaries, and to a lesser degree in larger vessels of the vascular lamina. In melanin-free tissue, haemoglobin serves as the primary site of energy absorption, which is thus shifted from the stroma to the vessel lumen. Irradiation of vessels in such tissue leads to thermocoagulation of plasma proteins and consequent stasis of blood flow.  相似文献   
109.
The effects of bezafibrate administered at 10 and 50 mg/kg/day for 7 days to male Sprague-Dawley (SD) and Lewis rats were investigated in order to determine the interrelation between the changes in serum and hepatic lipid contents and activities of selected peroxisomal, microsomal and mitochondrial enzymes in the two rat strains. In both strains, bezafibrate effectively reduced serum and hepatic lipids, increased the liver weight, induced a proliferation of peroxisomes, and selectively elevated the activities of carnitine acetyltransferase and of the enzymes of the peroxisomal -oxidation system. Moreover, immunoblotting revealed that the drug specifically enhanced the concentration of only those peroxisomal enzymes involved in fatty acid -oxidation. The data obtained demonstrate that although the responses initiated by bezafibrate are qualitatively similar in both strains, they differ in their magnitude in a dose-dependent manner, with the Lewis strain exhibiting a more pronounced response than the SD rats. These results show that dose-dependent strain differences as well as the generally known species differences should be taken into account in pharmacological and toxicological evaluations of fibrates in rodents. Furthermore, generalization and extrapolation from rodent studies should be treated with great caution.  相似文献   
110.
We report four patients (three male, one female) with septo-optic dysplasia and growth hormone deficiency. All had GH therapy for a period of four to eight years until reaching final height. In all four cases bone maturation during puberty was accelerated (1.4 to 1.9 "years"/year), resulting in a final height which was clearly below the predicted height. The progress of pubertal stages was very short in all patients. In three patients TSH and prolactin release after TRH stimulation were increased. These data support a hypothalamic original of the endocrine disorder. Insufficient GH release, even after repeated GHRH stimulation, is in contrast to this assumption. In one case there was a late manifestation of neurohormonal diabetes insipidus, which indicates the possibility of later disease progression. MR imaging of the brain demonstrated variable malformation of the septum pellucidum, chiasma and nervus opticus or the pituitary gland, respectively.  相似文献   
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