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71.
From mid-October 1989 to mid-July 1990 all newly admitted residents to Bury Local Authority Residential Homes were comprehensively medically screened. In a series of 100 residents eight had early Parkinson's disease (six of them hitherto undiagnosed). Seven showed evidence of Vitamin C deficiency. Of the seven showing evidence of deficiency, four suffered from early Parkinson's disease. Of the 93 without evidence of Vitamin C deficiency only four had Parkinson's disease. This indicates a significantly higher prevalence of Parkinson's disease in the group with Vitamin C deficiency (P less than 0.001 using Fisher's exact).  相似文献   
72.
Background. Hypoxia and warm ischemia produce severe injury to cardiac grafts harvested from non–heart-beating donors. To potentially improve recovery of such grafts, we studied the effects of intravenous phenylephrine preconditioning.Methods. Thirty-seven blood-perfused rabbit hearts were studied. Three groups of non–heart-beating donors underwent intravenous treatment with phenylephrine at 12.5 (n = 8), 25 (n = 7), or 50 μg/kg (n = 7) before initiation of apnea. Non–heart-beating controls (n = 8) received saline vehicle. Hypoxic cardiac arrest occurred after 6 to 12 minutes of apnea, followed by 20 minutes of warm in vivo ischemia. A 45-minute period of ex vivo reperfusion ensued. Nonischemic controls (n = 7) were perfused without antecedent hypoxia or ischemia.Results. Phenylephrine 25 μg/kg significantly delayed the onset of hypoxic cardiac arrest compared with saline controls (9.6 ± 0.5 versus 7.7 ± 0.4 minutes; p = 0.00001), yet improved recovery of left ventricular developed pressure compared with saline controls (57.1 ± 5.3 versus 41.0 ± 3.4 mm Hg; p = 0.04). Phenylephrine 25 μg/kg also yielded a trend toward less myocardial edema than saline vehicle (p = 0.09).Conclusions. Functional recovery of nonbeating cardiac grafts is improved by preconditioning. We provide evidence that the myocardium can be preconditioned with phenylephrine against hypoxic cardiac arrest.(Ann Thorac Surg 1997;63:1664–8)  相似文献   
73.
Infertility may occur in patients with unilateral testicular torsion whose contralateral testis is intact. Depending on this observation, the physicians have begun to examine the contralateral testis. In the present prospective study we aimed to examine the histopathologic alterations occurring in the contralateral testicle with time. Sixty adult male albino rats were included in the programme, and following experimental torsion the histopathologic findings, especially those in the contralateral testis, were evaluated after 4–12 weeks. Long-term and high degree torsion of the testicle led to varying degrees of deterioration in the germinal epithelium and interstitial cells of the contralateral testicle. Histopathologic alterations were reversed in 12 weeks. Tubular diameter and testicular volume also decreased in accordance with the histopathologic alteration. In our opinion, orchiectomy following torsion of one testicle will limit potential histopathologic alterations in the contralateral testicle.  相似文献   
74.
Twenty adolescent male sexual offenders were evaluated by penile plethysmography on two separate occasions. Stimuli consisted of 19, two-minute audiotaped cues. Test-retest reliability was demonstrated for 15 of the 19 audiotaped vignettes. The highest correlations were found for those sexual behaviors in which the adolescents had engaged.  相似文献   
75.
Background. Extreme hemodilution caused by relatively large prime volumes required for cardiopulmonary bypass in infants causes a dilutional coagulopathy, characterized by low concentrations of fibrinogen and other circulating coagulation factors. Modified ultrafiltration results in hemoconcentration and is associated with decreases in postoperative bleeding and transfusion requirements in children. This study was undertaken to quantify the effect of modified ultrafiltration on concentrations of fibrinogen, plasma proteins, and platelets in infants and small children.

Methods. Twenty patients less than 15 kg were studied. Cardiopulmonary bypass circuits were primed with crystalloid solutions. Red blood cells were added during cardiopulmonary bypass for hematocrits less than 15%. Colloid solutions were not administered. Concentrations of fibrinogen, plasma proteins, and platelets, and hematocrit were measured before cardiopulmonary bypass, before modified ultrafiltration, and after modified ultrafiltration.

Results. Modified ultrafiltration was associated with significant (p < 0.001) increases in hematocrit (19% ± 6% to 31% ± 9%), fibrinogen (65 ± 29 to 101 ± 45 mg/dL), and total plasma proteins (2.7 ± 0.3 to 4.9 ± 0.7 g/dL), but no change (p = 0.129) in platelet count.

Conclusions. We conclude that modified ultrafiltration significantly attenuates the dilutional coagulopathy associated with cardiopulmonary bypass in infants.  相似文献   

76.
Michaelis constants and maximal velocities for phenylacetaldehyde (a metabolite of phenylethylamine), 3,4-dihydroxyphenylacetaldehyde (a metabolite of dopamine), 5-hydroxyindole acetaldehyde (a metabolite of serotonin), and 3,4-dihydroxyphenylglycolaldehyde (a metabolite of epinephrine and norepinephrine) have been determined for both cytoplasmic (E1) and mitochondrial (E2) isozymes of human liver aldehyde dehydrogenase (EC 1.2.1.3). Kinetic constants with biogenic aldehydes have never been previously determined for individual homogeneous isozymes of aldehyde dehydrogenase from any species. Mathematical treatment of these constants suggests that competition with acetaldehyde during alcohol metabolism would severely inhibit dehydrogenation of biogenic aldehydes with the mitochondrial and not the cytoplasmic isozyme of human liver aldehyde dehydrogenase.  相似文献   
77.
In the presence of ATP, MgCl2, and CoASH, somal plasma membranes isolated from rat cerebral cortex were active in transferring arachidonic acid to phosphatidylinositols, phosphatidylcholines, and triacylglycerols. Ethanol (350-525 mM) added to the incubation mixture inhibited arachidonic acid incorporation into phospholipids, while it enhanced the incorporation into triacylglycerols. Under these conditions, ethanol was found to react with arachidonic acid to form arachidonoyl ethyl ester. The incorporation of labeled arachidonic acid into glycerolipids as well as the synthesis of ethyl esters required the presence of ATP and CoASH for maximal activity. Nevertheless, each uptake process exhibited a unique pH profile. The esterification of arachidonic acid was not specific for ethanol as other aliphatic alcohols (e.g., propanol and butanol) were also able to react with labeled arachidonic acid to form the respective esters. Somal plasma membranes isolated from mice after chronic ethanol administration showed an increase in arachidonoyl transfer to both phospholipids and triacylglycerols. When these membranes were challenged with ethanol (325 mM), those isolated from the chronic ethanol group showed a greater increase in the labeling of triacylglycerols and ethyl esters than those from controls. Thus, different acyltransferases exhibite different responses to the effects of ethanol in vitro and in vivo.  相似文献   
78.
Cholecystokinin (CCK) and bombesin (BBS) are neuropeptides of the brain and gut which have been shown to inhibit intake of ethanol. CCK octapeptide and BBS tetradecapeptide were injected intraperitoneally in both single doses and combinations of doses to determine interactions of the two peptides in the control of consumption of ethanol. Water-deprived rats were given access to 5% w/v ethanol for 30 min, followed by a 30-min access to water, daily. One minute before presentation of ethanol, rats were injected with either saline or one of ten peptide solutions (three of CCK alone, three of BBS alone, and four combinations of both). Results from the injections of single peptides were used to determine predicted inhibitions of the peptide combinations, assuming perfect additivity of doses. None of the actual values of inhibition of intake of ethanol by peptide combinations differed significantly from its predicted additive value. Endogenous CCK-like and BBS-like peptides may suppress intake of ethanol by an additive mechanism of inhibition.  相似文献   
79.
80.
This study was undertaken to test the hypothesis that malfunction of the nonadrenergic noncholinergic inhibitory system (NANCIS) induces hyperreactive airways. Antigen sensitized guinea pigs were divided into four groups: (1) antigen challenge (n = 6), (2) 2 min oxyhemoglobin (HbO2) + antigen challenge (n = 5), (3) 27 min HbO2 + antigen challenge (n = 4), and (4) 2 min HbO2 + transmural stimulation (TS) + antigen challenge (n = 6). These animals were sensitized with ovalbumin 10 days before the study. In addition, 12 normal control animals without antigen sensitization were used for comparison. Under artificial ventilation, the anesthetized-paralyzed animals were hourly injected with atropine (0.2 mg/kg) and propranolol (1 mg/kg). Cervical segment of the trachea was converted to a closed tracheal pouch filled with Krebs solution containing also atropine (1 microM) and propranolol (3.5 microM). A change in the pouch pressure (Pp) reflected NANCIS TS- or antigen (5 micrograms) challenge-induced relaxation and/or constriction. HbO2 was used to inhibit NANCIS transmitter. There was no significant difference between normal and sensitized animals in the NANCIS TS-induced relaxation. Antigen challenge resulted in biphasic alteration in Pp, an initial increase and then a decrease after about 7 min. HbO2 pretreatment alone did not potentiate antigen-induced increase in Pp. HbO2 + TS, however, significantly abolished the late relaxation phase after antigen challenge.  相似文献   
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