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91.
OBJECTIVE: Respiratory scleroma (RS) is a progressive, chronic, granulomatous disease caused by Klebsiella rhinoscleromatis. There is only one report of RS association with HLA-DQ3. In this study, molecular association of HLA class II and RS was determined. STUDY DESIGN AND SETTING: Nine RS patients and 163 healthy controls were compared. DQA1, DQB1, and DRB1 loci were typed. RESULTS: Statistical analysis demonstrated association between DQB1*0301 and susceptibility to RS (P(c) = 0.004). Haplotype analysis showed an association of DQA1*03011-DQB1*0301 (P = 1.21E-19) and DRB1*0407-DQA1*03011-DQB1*0301 (P = 0.0002). CONCLUSIONS: Results established that DQA1*03011-DQB1*0301 haplotype is a strong risk factor for development of RS.  相似文献   
92.
93.
Recent experimental studies and one clinical case have suggested that grafting tissue from the adrenal medulla into the brain may ameliorate the signs of Parkinson's disease. We describe the treatment of two young patients (35 and 39 years old) with intractable and incapacitating Parkinson's disease, in whom fragments of the adrenal medulla were autotransplanted to the right caudate nucleus. Clinical improvement was noted in both patients at 15 and 6 days (respectively) after implantation and has continued in both. Rigidity and akinesia had virtually disappeared in the first patient at 10 months after surgery, and his tremor was greatly reduced. A similar degree of improvement was present in the second patient at three months. We conclude that autografting of the adrenal medulla to the right caudate nucleus was associated with a marked improvement in the signs of Parkinson's disease in two patients, but our results are preliminary and further work is necessary to see whether this procedure will be applicable over the long term in other types of patients with Parkinson's disease.  相似文献   
94.
Several of the clinical and biochemical manifestations of biotin deficiency also occur in severe protein-energy malnutrition (PEM). Average plasma biotin concentrations were lower in 16 malnourished children (10 with marasmus, 3 with kwashiorkor and 3 with marasmic kwashiorkor) than in 31 controls. Lymphocyte mitochondrial carboxylase activities were studied in 11 controls and in 10 patients with PEM; on the average, they were lower in the patients. Their activation indices (the ratio of enzyme activity in cells incubated with biotin to activity in cells incubated without the vitamin) were higher in PEM. All these differences were statistically significant. None of these parameters were age-dependent in a range between 3 and 72 months. Carboxylase activities and plasma biotin levels increased to normal during nutritional recovery in two malnourished patients who were further studied. These results suggest that there is biotin deficiency in severe PEM. Urinary biotin concentrations, expressed per g of creatinine, were higher in the patients than in the controls; this may have been caused by increased renal clearance or by the reduced creatinine excretion which occurs in malnourished individuals. It will be important in future studies to determine the relative contribution of biotin deficiency to the malnourished phenotype.  相似文献   
95.
BACKGROUND: Electrophrenic pacing can be used in the management of ventilatory failure in quadriplegic patients. A study was undertaken to determine the pattern of transdiaphragmatic pressure (PDI) during the conditioning phase of electrophrenic pacing to see if it had a possible role in optimising the process of conditioning. METHODS: The tidal volume (TV) and PDI were measured in a group of six quadriplegic patients commencing ventilation by low frequency pulse stimulation (7-10 Hz) and low respiratory rate stimulation (< 10 breaths/min). RESULTS: Tidal volume increased between baseline and month 1 (4.33 ml/kg, p < 0.001) and between months 1 and 2 (3.00 ml/kg, p < 0.05) and then stabilised. PDI was higher during bilateral diaphragmatic pacing (mean (SD) 1.73 (0.30) kPa) than with either left (1.15 (0.34) kPa) or right (0.86 (0.37) kPa) unilateral pacing. PDI varied throughout the observation period, probably by interaction between recovery of the diaphragmatic fibres and the pacing regimen. CONCLUSIONS: Patients with quadriplegia due to high spinal injury can be maintained with ventilation by continuous electrophrenic pacing. The control criteria used in this study for pacing were tidal volume and the patient's tolerance, and the PDI measurement did not contribute any additional information to help with managing the conditioning process.  相似文献   
96.
Abuse liability and acute subjective and psychomotor effects of flunitrazepam were assessed in ten methadone-maintained males with history of benzodiazepine and alcohol use, who voluntarily participated in a double-blind, controlled, cross-over, randomized clinical trial. There were six experimental sessions in which a single oral dose of flunitrazepam 1, 2, and 4 mg; triazolam 0.5 and 0.75 mg; and placebo was given. Evaluations included physiological measures; psychomotor performance tasks (simple reaction time, Digit Symbol Substitution Test, balance task, Maddox-wing device); and self-administered subjective effects questionnaires [Addiction Research Center Inventory (ARCI), Profile of Mood States (POMS), a series of visual analog scales (VAS)]. All drugs but flunitrazepam 1 mg caused an impairment of psychomotor tasks. Effects were more evident with the highest doses of both drugs. Only flunitrazepam 4 mg produced a significant decrease in balance time. Triazolam 0.75 mg induced increases in sedation measured by ARCI-PCAG, depression in POMS, and VAS-drowsiness scores. Flunitrazepam 4 mg caused euphoria-related effects as measured by increases in ARCI-MBG and “high” scores in the VAS. Our findings of flunitrazepam-induced euphoria in methadone-maintained subjects together with epidemiological evidence of flunitrazepam abuse by opioid dependents, suggest that it may be included in the group of benzodiazepines with a relatively high abuse potential. Received: 13 February 1998/Final version: 1 May 1998  相似文献   
97.
A high-performance liquid chromatographic (HPLC) method is described for the assay of the active metabolite [1-(2-pyrimidinyl)piperazinel of buspirone, an anxiolytic agent, in rat plasma.

The method is based on the use of ion-pair HPLC coupled to a liquid—solid extraction scheme. Samples of rat plasma (2 ml) with internal standard (1-phenylpiperazine), adjusted to pH 10.5 with borate buffer, were loaded on to a preactivated C-18 cartridge. The metabolite and the internal standard were eluted with 5 ml of methanol and injected on to a reversed-phase 10-μm Spherisorb ODS-2 column. The column was eluted with a mobile phase of 0.005 M sodium lauryl sulphate in citrate buffer (pH 3.6)-acetonitrile (65:35, v/v) at 2 ml min−1. Detection was carried out at 248 nm. The recovery of the metabolite was 55%. The method was applied to the determination of the metabolite in rat plasma after oral dosing (25 mg kg−1) of the parent compound.  相似文献   

98.
August Weismann popularized the notion that metazoans have a potentially immortal germ line separated from a mortal soma, and evolutionary biologists regard senescence as an evolved characteristic of the soma. Many have claimed that metazoans that do not sequester their germ line have no clear distinction between germ line and soma, and consequently they should lack senescence. Here we present experimental evidence that senescence occurs in the asexually reproducing marine oligochaete Paranais litoralis. We also analyze data reported in Sonneborn's classical study and show that the rhabdocoel Stenostomum incaudatum undergoes senescence. We argue that the stability of commitment to somatic function and the fact that asexual metazoans form their germ cells from undifferentiated stem cells are sufficient to allow for senescence of the asexual metazoan's soma. Thus the evolution of somatic differentiation, and not germ-line sequestration, would be the necessary condition for the evolution of senescence.  相似文献   
99.
A comparative statistical analysis of "synaptic ribbons" evolution over a 24 hour period during two different photoluminous seasons (September, and winter) is carried out. Seventy male rats were used. Statistical analysis involved the Kolmogorov-Smirnov test, variance analysis, the Student t-test and Pearson's correlation test. The results show that "synaptic ribbons" evolve during the circadian phase and through two different seasons, with a clear and marked influence of point-time (p < 0.0001) and season (p < 0.0001).  相似文献   
100.
Blood rheological properties were studied in 21 patients suffering from essential hypertension (EHT), degree I-II according to WHO criteria. These patients were diagnosed "de novo". The whole blood filterability (WBF), blood viscosity (BV) at 230 s-1 and 23 s-1, red cell deformability (FI), erythrocyte aggregation in autologous (MEA) and normal plasma (MEAc), fibrinogen (Fbg) and hematocrit (Ht) have been evaluated. In the hypertensive patients we have found decreased WBF, greater BV and FI in comparison with the control group (p less than 0.001). Likewise, MEA and Fbg were increased, though the differences were less significant (p less than 0.01). The evaluation of Ht did not show any differences between the two groups. The results suggest that in the newly diagnosed EHT, clear hemorheological alterations occur, both in plasma and in the erythrocytes, which could play a role in the pathogenesis of the aforementioned disease.  相似文献   
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