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108 patient were operated on the Neurosurgical Department of the Military Clinical Hospital in Wroc?aw since 1989 till 1991. The stability of the lumbar spine after hemilaminectomy and laminectomy with disc excision and interbody fusion was analysed. The period after operation ranged from 6 months to 2 years. Signs of clinical and radiological instability were the base of the study. Respective segmental motions in maximal ante- and retroflexion were calculated. Horizontal intercorporal dislocation was assessed. No signs of instability where found in the analysed material. The results after laminectomy and hemilaminectomy were similar. The failures were not caused by instability.  相似文献   
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The antimicrobial activity of vancomycin and related glycopeptide antibiotics is due to stereospecific recognition of polypeptide components in bacterial cell walls. To better understand how these antibiotics recognize polypeptide determinants, we have developed dynamic models of the complexes formed by the vancomycin aglycon and two different dipeptide ligands, Ac-D-ala-D-ala and Ac-D-ala-gly. Molecular dynamics simulations of the two complexes, initially conditioned with distance constraints derived from two-dimensional nuclear magnetic resonance (NMR) studies, are conformationally stable and propagate in a manner consistent with the NMR-derived constraints after the constraints are removed. Free energy calculations accurately predict the relative binding affinity of these two complexes and help validate the simulation models for detailed structural analysis. Although the two ligands adopt similar conformations when bound to the antibiotic, there are clear differences in the configuration of intermolecular hydrogen bonds, the overall shape of the antibiotic, and other structural features of the two complexes. This analysis illustrates how complex structural and dynamic factors interrelate and contribute to differences in binding affinity.  相似文献   
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The relation of the physiological releases of growth hormone-releasing hormone (GHRH) and growth hormone (GH) into the circulation in various conditions was investigated using a sensitive and specific radioimmunoassay for plasma GHRH. The mean fasting plasma level of immunoreactive (IR)-GHRH in 72 normal adults was 10.3 +/- 0.5 (mean +/- SEM) pg/ml and there was no significant sex difference in the level. The concentrations of IR-GHRH in plasma from the umbilical artery and umbilical vein were 107.3 +/- 20.5 pg/ml and 33.6 +/- 3.8 pg/ml, respectively, and a marked arterio-venous gradient was observed in all 12 individuals examined. The plasma level of IR-GHRH in the maternal vein was significantly lower than that in the cord blood, but was similar to that in non-pregnant women. In normal adults, although there was no apparent fluctuation in the level of plasma IR-GHRH or of plasma GH during bed rest, a significant increase of plasma IR-GHRH was detected followed by, or synchronized with the surge of plasma GH after oral administration of L-dopa. In contrast, on L-arginine infusion, no proportional elevation of plasma IR-GHRH with increase in plasma GH was observed. During and after intravenous infusion of somatostatin, the circulating IR-GHRH level did not increase, but on stopping the infusion there was an immediate and marked rebound surge of GH. We conclude that 1) the elevated IR-GHRH in the cord blood plasma originates from the fetus and may have a primary role in enhancing secretion of GH which promotes growth in early human life, and 2) the participations of GHRH in the mechanisms of GH secretion seen after administrations of L-dopa, L-arginine and somatostatin are different.  相似文献   
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OBJECTIVE: To examine the occurrence of elevated personality disorder (PD) dimensional scores in a community sample of young adults as a function of the occurrence of Axis I disorders through age 18 years. METHOD: 299 individuals who had been interviewed regarding Axis I disorders twice while in adolescence (first when 14 through 18 years of age) were carefully assessed regarding Axis I and II psychopathology at age 24. RESULTS: The prevalence of PD diagnoses was relatively low (3.8% in participants with a history of Axis I versus 1.7% in participants with no Axis I history). The occurrence of all four Axis I diagnostic categories (major depression, anxiety disorders, disruptive behavior disorders, substance use disorders) in childhood and adolescence was associated with elevated PD dimensional scores. The likelihood of elevated PD dimensional scores increased as a function of the number of Axis I disorders. Elevated PD scores were significantly associated with a negative course of major depression. CONCLUSIONS: Although the rates of PDs were low, the findings suggest a substantial degree of association between early-onset Axis I disorders and Axis II psychopathology in young adulthood. More research is needed to develop assessment and treatment recommendations addressing the early manifestations of PDs.  相似文献   
156.
A recombinant truncated form (delta1-102/delta428-452) of the non-heme iron-dependent metalloenzyme human phenylalanine hydroxylase (hPAH, phenylalanine 4-monooxygenase; EC 1.14.16.1) was expressed in E. coli, purified to homogeneity as a homodimer (70 kDa) and crystallized using the hanging drop vapour diffusion method. The crystals are orthorhombic, space group C222 with cell dimensions of a = 66.6 A, b = 108.4 A, c = 125.7 A. The calculated packing parameter (Vm) is 3.24 A3/Da with four 2-fold symmetric dimers (or eight momomers) in the unit cell. Data have been collected to 2.0 A resolution.  相似文献   
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Impaired adrenal function during perioperative stress carries the risk of acute cortisol (Cs) deficiency (Addisonian crisis), which may be critical without Cs supplementation. Thus, with evidence of dysfunction of the adrenal glands perioperative substitution is indicated. However, it is unclear whether unilateral adrenalectomy may attenuate the adrenocorticoid response. Glucocorticosteroids are potent agents with several well-known side effects. The purpose of the present study was to evaluate if routine Cs supplementation is justified and necessary in patients undergoing adrenalectomy during nephrectomy for renal-cell cancer. METHODS: Ten consecutive patients with renal-cell cancer (5 male, 5 female; age 58 +/- 10 years; ASA class I-II) who underwent adrenalectomy with radical nephrectomy were included in this study. None of them had received steroids for at least 5 years prior to the current surgery. Anaesthesia was induced with propofol, fentanyl, and vecuronium and maintained with isoflurane (PetIso: 0.8 +/- 0.3 vol.%) in nitrous oxide (66%) and oxygen. The patients did not receive any Cs treatment perioperatively. Monitoring included heart rate (beats/min), mean arterial pressure (mm Hg), central venous pressure (mm Hg), O2 saturation (%), and body temperature (degrees C, rectal). Plasma analyses included Cs (Cs radioimmunoassay IBL; normal 120-250 ng/ml), adrenocorticotropic hormone (ACTH) (ACTH-II IRMA; normal (10-50 pg/ml), glucose, and electrolytes determined as follows: preoperatively (8 a.m.); 1-6 h (60-min intervals) after surgery; pre-corticotropin-releasing hormone (CRH) (Corticobiss: 2 micrograms/kg i.v.) administration (1st postop. day at 8 a.m. and after 30, 60, 90, and 120 min. The study was completed with plasma analyses on postoperative days 2 and 3 (8 a.m.). RESULTS: None of the patients showed any clinical signs of plasma parameter of adrenal insufficiency due to the unilateral adrenalectomy. Serum levels (median: 25%/75% percentiles) of Cs (maximum [max.]:253 [217/288] ng/ml) and ACTH (max.:347 ([68/405] pg/ml) were elevated above the normal range postoperatively). After intravenous stimulation with CRH (1st postoperative day), Cs (max.:273 [248/310] ng/ml) and ACTH (max.: 107 ([75/275] pg/ml) were also increased above normal. During postoperative days 2 and 3 (8 a.m.) Cs and ACTH remained in the high-normal range. CONCLUSIONS: Data from this study indicate that unilateral adrenalectomy was associated with adequate spontaneous Cs secretion by the remaining adrenal gland. Moreover, stimulation with CRH demonstrated adequate reactivity of the pituitary-adrenal axis. None of the patients showed any signs of Cs deficiency by clinical or serum parameters. Therefore, we do not recommend routine Cs supplementation in patients undergoing adrenalectomy during tumor nephrectomy, nevertheless, Cs supplementation remains necessary for patients with primary hypothalamic-pituitary-adrenal dysfunction (Addison's disease) or hyperfunction (Cushing's disease).  相似文献   
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