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51.
Calculated therapeutic doses of digitalis did not produce a significant change in the coronary blood flow of the dog. This confirms the results of Essex, Herrick, Baldes, and Mann.28Calculated toxic doses of digitalis decreased the coronary blood flow of dogs four to six hours after the drug had been administered. The diminution of flow persisted for several days after a single toxic dose of the drug.No myocardial lesions were observed after a therapeutic dose of digitalis, nor were they observed in one animal which received a toxic dose of digitalis. In the latter animal the coronary blood flow returned to the preinjection level within two days.Myocardial lesions were observed in one animal in which the coronary blood flow was kept well below the control level for twelve days by repeated injections of digitalis (toxic range).The diminution of coronary blood flow after the injection of toxic doses of digitalis could not be correlated consistently with changes in the pulse rate or systemic blood pressure.After the injection of toxic doses of digitalis the coronary blood flow returned to the control level in several experiments, and the animals recovered completely.  相似文献   
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Summary The influence of the palatal vault dimensions on tongue position is here studied through evaluation of the in‐mouth air cavity (IMAC) volume when the mandible is in maximal intercuspal position. A sample of 35 women (mean age 21·2 ± 1·0) and 15 men (mean age 22·1 ± 0·9) was selected. The sagittal cross‐section area of the IMAC, which is modulated by the tongue position, was measured on lateral cephalograms. Dental casts were used to measure the palatal vault volume, which was defined by the occlusal plane, the hard palate and the posterior face of the second molars. Palatal vault volume allowed deduction of the IMAC volume through a rule of three procedure relating volume to area ratios. No IMAC could be calculated from cephalograms of 10 subjects who had the tongue stuck to the palate. For the 40 other subjects, the IMAC volume was 8·9 ± 4·8 mL. It was 2 mL larger in men (n = 14) than in women (n = 26) and was the largest in skeletal Class III and the smallest in skeletal Class II (P > 0·05). IMAC volume was strongly correlated with palatal vault height but neither with palatal width nor length. It was thus assumed that the height of the palatal vault could influence the most observed position of the tongue but this does not exclude a possible growth influence of the tongue on its surrounding skeletal structures.  相似文献   
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We investigated the impact of pre-existing mental ill health on postpartum maternal outcomes. Women reporting childbirth trauma received counselling (Promoting Resilience in Mothers' Emotions; n?=?137) or parenting support (n?=?125) at birth and 6 weeks. The EuroQol Five dimensional (EQ-5D)-measured health-related quality of life at 6 weeks, 6 and 12 months. At 12 months, EQ-5D was better for women without mental health problems receiving PRIME (mean difference (MD) 0.06; 95 % confidence interval (CI) 0.02 to 0.10) or parenting support (MD 0.08; 95 % CI 0.01 to 0.14). Pre-existing mental health conditions influence quality of life in women with childbirth trauma.  相似文献   
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Background

Bilharzia-associated bladder cancer (BAC) is a major health problem in countries where urinary schistosomiasis is endemic. Characterization of the genetic alterations in this cancer might enhance our understanding of the pathogenic mechanisms of the disease but, in contrast to nonbilharzia bladder cancer, BAC has rarely been the object of such scrutiny. In the present study, we aimed to characterize chromosomal imbalances in benign and malignant post-bilharzial lesions, and to determine whether their unique etiology yields a distinct cytogenetic profile as compared to chemically induced bladder tumors.

Methods

DNAs from 20 archival paraffin-embedded post-bilharzial bladder lesions (6 benign and 14 malignant) obtained from Sudanese patients (12 males and 8 females) with a history of urinary bilharziasis were investigated for chromosomal imbalances using comparative genomic hybridization (CGH). Subsequent FISH analysis with pericentromeric probes was performed on paraffin sections of the same cases to confirm the CGH results.

Results

Seven of the 20 lesions (6 carcinomas and one granuloma) showed chromosomal imbalances varying from 1 to 6 changes. The most common chromosomal imbalances detected were losses of 1p21-31, 8p21-pter, and 9p and gain of 19p material, seen in three cases each, including the benign lesion.

Conclusion

Most of the detected imbalances have been repeatedly reported in non-bilharzial bladder carcinomas, suggesting that the cytogenetic profiles of chemical- and bilharzia-induced carcinomas are largely similar. However, loss of 9p seems to be more ubiquitous in BAC than in bladder cancer in industrialized countries.
  相似文献   
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Neural networks in ventilation-perfusion imaging   总被引:2,自引:0,他引:2  
Fisher  RE; Scott  JA; Palmer  EL 《Radiology》1996,198(3):699
  相似文献   
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