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11.
 In order to determine the dynamics of hematopoietic cell turnover, proliferative activity and incidence of apoptosis (programmed cell death) were evaluated in bone marrow trephine biopsies. Selection of patients (20 in each group) included in addition to a control group, idiopathic thrombocytopenia (ITP), reactive thrombocytosis (TH), secondary polycythemia-smokers' polyglobuly (PG), primary (essential-hemorrhagic) thrombocythemia (PTH), polycythemia vera (PV), and finally acute myeloid leukemia (AML). Apoptosis was demonstrated by the in situ end-labeling technique (ISEL) and proliferative activity by applying the monoclonal antibody PC10 raised against proliferating cell nuclear antigen (PCNA). To assess dynamic features of hematopoiesis, an index was calculated consisting of the ratio between PCNA-positive nuclei and the apoptotic cell fraction. This factor was termed the hematopoietic turnover index (HTI). Morphometric analysis revealed that the HTI was significantly increased in AML and PV. According to cell culture studies both disorders are characterized by either a prevalent proliferation of the myeloid or erythroid cell mass. On the other hand, PG, PTH, and TH showed no relevant enhancement of this index in comparison to the control specimen. In vitro experiment results are in keeping with the finding that PG and PTH are not associated with a significant expansion of the erythroid lineage (CFU-E). Similar to ITP and TH, in PTH megakaryocyte proliferation (CFU-MEG) is the predominant feature of cell turnover. Differences between PTH and TH are in line with the reduced in vitro formation of CFU-MEG in the latter disorder. In conclusion, our in situ study on turnover rates of the bone marrow in various neoplastic and reactive lesions extends previous experimental data on hematopoietic cell kinetics. Received: 10 March 1997 / Accepted: 18 May 1997  相似文献   
12.
Abstract From August to October 1991, the periodontal status of 1001 Yemenis representing the age groups 12-14, 15-19, 20-24 and 35-44 years was recorded and evaluated with preference to the CPITN, the calculus index and clinical attachment levels. The impact of chewing khat, the leaves of a cultivated, alkaloid shrub, and of using the traditional miswak chewing stick for oral hygiene purposes were investigated. The results show that 6.9% of the juvenile probands (15-19 years) had healthy periodontal tissue (CPITN 0). whereas bleeding on probing and calculus (CPITN 1+2) were registered in 86.2%. In the 35-44 year age group. 1.7% were periodontally healthy, whereas 84.5% displayed plaque retention or shallow pocketing (CPITN 2-3) and 12.5% deep pocketing (CPITN 4). The treatment needs in all age groups are confined primarily to calculus removal and instruction in oral hygiene. The clinical attachment level and the calculus index revealed age-related attachment loss and calculus formation, primarily among male probands. The higher khat consumption among the male population is reflected in its detrimental effect on the periodontal tissue, especially among younger probands. Oral hygiene aids have also an influence on periodontal status, with a toothbrush proving more efficient than the miswak. WHO efforts directed towards prophylactic programs need to be intensified but can be staffed by dental hygienists.  相似文献   
13.
The changes in bladder function occurring after a surgical alteration in bladder outflow resistance were studied in 20 males undergoing transurethral prostatectomy (TURP) and in 20 females undergoing an endoscopic bladder neck suspension (EBNS). Serial cystometrograms (CMG) were performed before operation, and on alternate days after spontaneous micturition was re-established, for 5 days in the males and for 21 days in the females. CMGs were repeated at 3 months and 1 year after operation. After TURP voiding pressures (Pdet) fell rapidly from a mean of 118 cm H2O before operation to 57 cm H2O at 5 days, with an increase in flow rate during this time from 10.5 ml/s to 24 ml/s. Detrusor instability that had been present in 14 patients resolved within 2 days in 12. There was no further significant urodynamic change over the 1-year study period. After EBNS, there was an early rise in voiding pressure (Pdet rose from 26 cm H2O before operation to 42 cm H2O at 3 days). This continued to increase up to 21 days particularly in those patients with initial large residuals. Three patients developed detrusor instability. Flow rates were greatly reduced at first (27 ml/s before operation and 13 ml/s at 3 days), and gradually increased in line with voiding pressures, yet were still diminished 1 year after operation. The urodynamic changes following a reduction in bladder outflow resistance by TURP are immediate and sustained and unlikely to be the result of structural changes within the bladder wall. EBNS produces an increase in outflow resistance and it can be several weeks before balanced voiding is achieved, with significantly increased detrusor pressures needed to achieve complete bladder emptying at a reduced flow rate.  相似文献   
14.
Hereditary hypertriglyceridemic rats (hHTg) were developed as a new genetic model for the study of relationships between blood pressure (BP) and metabolic abnormalities. This strain has been produced by selective inbreeding from Wistar rats according to the rise of plasma triglycerides induced by a high-sucrose diet. Though hHTg rats display hypertriglyceridemia, impaired glucose tolerrance, hyperinsulinemia, insulin resistance and increased BP even without nutritional stimuli, high sucrose feeding further aggravates these symptoms. High plasma triglycerides levels in hHTg rats seem to be a consequence of their hyperproduction. Impaired insulin action is responsible for the defective glucoregulation in this strain. The loss of insulin responsiveness might be due to a reduction in the number of glucose transporters. Highly significant relationships among plasma triglycerides, ouabain-resistant Na+ transport and BP were demonstrated in the hHTg rats. Segregating populations (F2 hybrids) should be used for genetic analysis of the primary role of lipid and/or ion transport abnormalities in the pathogenesis of this form of genetic hypertension.  相似文献   
15.
Nasal resistance is affected by posture. In this study, the effects of supine and lateral recumbent positions were investigated in eight normal subjects and 31 patients with allergic rhinitis. Of the 31 patients with allergic rhinitis, five showed unilateral complete nasal obstruction and one patient showed bilateral complete obstruction during the change of posture. Total nasal resistance had a tendency to increase with repeating the change of posture (a paired t-test, P < 0.05). The supine and lateral recumbent positions did not induce variable changes in total nasal resistance in normal subjects. Posture induces complete nasal obstruction in the supine or lateral recumbent positions in some patients with allergic rhinitis.  相似文献   
16.
Background. A single deep inspiration (DI) is known to be a potent bronchodilator but it is not known if repeated DI can accelerate sustained recovery from bronchoconstriction. Methods. We induced sustained bronchoconstriction using increasing concentrations of nebulized methacholine (Mch) during tidal breathing and assessed airway narrowing by measuring respiratory resistance (Rrs) using forced oscillation in six healthy subjects. On separate days we examined the effects of DI every 3 minutes and of prohibition of DI on recovery of Rrs for 30 minutes after the end of Mch nebulization. Results. Bronchoconstriction (Rrs ∼ 150% above baseline) was induced. DI during recovery had a transient bronchodilator effect but no cumulative effect. At 30 minutes after end of nebulization (and 2 minutes after the last DI) Rrs was 87% above baseline compared to 93% above baseline when DI was prohibited. Conclusion. Recovery from induced bronchoconstriction with methacholine was slow (∼ 2%/min) and not accelerated by frequent DI.  相似文献   
17.
18.
Objective: To analyze quantitatively the synergistic and antagonistic effects of combined oxymatrine (OMT) and 5-fluorouracil (5-GU) on a cell line of human liver cancer (HepG2) with median-effect principle in vitro. Methods: The median-effect principle and MTT method were used in the quantitative analysis of effects of the two drugs. Results: Cytotoxic activity of the individual drugs enhanced as drug concentration increased. As fa=0.41, a CI equal to 1 indicated additivity; fa<0.41, a CI less than 1 indicated synergy; and fa>0.41, a CI greater than 1 indicated antagonism. The sequence of administration did not influence the cytotoxic activity of the combined antitumor drugs. The ratio of drug concentration was a factor that can influence the killing effect. Conclusion: The combined drugs interaction (CI<1) was synergistic at lower concentration and antagonistic at higher concentration. The ratio of drug concentration is a factor that can influence the killing effect. Biography: HE Song(1965–), male, doctor of medicine, associate professor, Chongqing Medical University, majors in gastroenterology.  相似文献   
19.
20.
Abstract Changes in colonic motor activity during aerobic exercise were investigated in ten regularly exercising volunteers (five males and five females) aged 27–70 years. Motility was recorded with a catheter containing three solid-state pressure transducers spaced 5 cm apart. The motility catheter was advanced 40–50 cm from the anal verge by flexible sigmoidoscope without anesthesia at least 60 min prior to testing. Manometric recordings were made from the colon during a 1-h pre-exercise rest period, 1 h of jogging at 70–80% maximum heart rate, and 1-h post-exercise rest period. The dominant frequency of contractile activity in the colon shifted from 1–4 cpm during rest, to 4–9 cpm with the onset of exercise. Activity also shifted from sporadic, isolated contractions to regular, propagated contractions in six of ten subjects, five of whom reported a history of runner's diarrhoea. The dominant frequency returned to 1–4 cpm during the post-exercise period. These changes in distal colonie motility may account for the diarrhoea which some subjects experience during intense, acute exercise.  相似文献   
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