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81.
82.
Summary Forty three patients, admitted to the department of Neurological Surgery for management of central nervous system tumours, were studied pre-operatively for serum myelin basic protein immunoreactivity as a marker of central nervous system lesion and for circulating immunoglobulins and complement (C3) levels. Myelin basic protein concentration did not appear to correlate with tumour type or grade. Serum immunoglobulin levels were found to be within the normal range but the mean IgM level was significantly higher in the glioma group when compared with meningiomas.  相似文献   
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84.
Summary— With respect to the heart, the prolonged existence of hypertension, both in man and in experimental animals is predominantly characterized by an increase in left ventricular myocardial mass. In this process, the autonomic nervous system plays an important role. Although endogenous catecholamine stimulation of the heart is mainly exerted via the β-adrenoceptors, in several mammalian species, the stimulation of cardiac α-adrenoceptors also mediates positive inotropic actions. We investigated the functional responses of isolated hypertrophied hearts taken from spontaneously hypertensive rats (SHR) and rats with an induced aortic stenosis (ASR) to various α1-adrenoceptor agonists and compared them with those from age matched Wistar Kyoto (WKY) and "sham" operated controls. Accordingly, we studied the functional response to: methoxamine (α1), cirazoline (α1) and phenylephrine (α1 > β1). The inotropic response to the α1-adrenoceptor agonists cirazoline and methoxamine proved to be significantly weaker in hypertrophied hearts from SHR and ASR than in non-hypertrophied hearts from WHY and "sham" operated controls ( p < 0.05). The inotropic response to phenylephrine remained intact in hypertrophied myocardial tissue. However, it was significantly reduced when the hearts were pre-treated with the intracellular Ca2+-antagonists ryanodine and TMB-8. These findings show that the mechanism of sarcolemmal Ca2+ release, activated by phenylephrine, is still intact in the hypertrophied myocardial cell. In conclusion, these data show that cardiac hypertrophy, be it of genetical or mechanical origin, leads to a reduced response of the isolated heart to α1-adrenoceptor stimulation.  相似文献   
85.
There is disagreement among authors as to what criteria are most reliable in assessing postnatal fetal age. A comparison–for objectivity, accuracy, and frequency of use– of specific criteria was made using three independent examiners at different educational levels: a second-year medical student, a perinatal nurse practitioner, and a pediatrics resident. It was shown that trained examiners develop favorite criteria which differ among examiners and thus sacrifice accuracy; however, accurate assessment of fetal age can be accomplished by an examiner with minimum clinical knowledge.  相似文献   
86.
We have developed an improved semiconductor recording probe for monitoring motility of the upper small intestine in humans. The probe consists of six ultraminiature silicon pressure sensors spaced 10 cm apart and encased in a flexible polyurethane sheath. The probe is small [2.67 mm (8F) diameter], is easily passed transnasally, and is tolerated by patients for prolonged recording periods (24–36 hr) with a minimum of discomfort. The initial semiconductor and catheter material were those designed for use in the cardiovascular system, but they proved to be easily damaged by gastric acid and enzymes. After improvement of this probe, we now have recordings from more than 100 patients for an approximate total of 6000 hr of recording time. The improved probe is a durable recording device that facilitates the investigation of motility of the small intestine in humans in health and disease.This study was supported by funds from the Medical Research Service of the Veterans Administration and by National Institutes of Health Clinical Research Center grant RR-82.  相似文献   
87.
Zusammenfassung An 6 normalen männlichen Freiwilligen im Alter von 20–26 Jahren wurden Plasmacortisol und -renin stündlich, Plasmaaldosteron, -angiotensinogen und -angiotensinasen alle 3 Std über jeweils 24 Std unter Kontrollbedingungen und anschließend unter Suppression der ACTH-Freisetzung durch Dexamethason gemessen.Die höchsten Cortisolspiegel fanden sich gegen 7 Uhr, die niedrigsten zwischen 21 und 1 Uhr. Die Gabe von Dexamethason führte zu konstant niedrigen Cortisolkonzentrationen.Aldosteron war unter Kontrollbedingungen und unter Dexamethason gegen 4 Uhr am höchsten und zeigte niedrigste Werte zwischen 16 und 22 Uhr. Zwischen den mittleren Aldosteronkonzentrationen entsprechender Zeitpunkte der Kontroll- und der Dexamethasonperiode bestanden keine signifikanten Unterschiede.Ähnlich dem Aldosteron zeigte das Plasmarenin Maximalwerte gegen 4 Uhr. Alle Mittelwerte entsprechender Zeitpunkte zwischen 7 und 23 Uhr und die jeweiligen 24 Std-Mittelwerte jedes einzelnen Probanden waren unter dem Einfluß von Dexamethason signifikant erhöht.Für die Existenz circadianer Rhythmen des Angiotensinogens und der Angiotensinasen konnte kein Anhalt gewonnen werden. Dexamethason bewirkte keine signifikanten Veränderungen dieser Parameter.Die Ergebnisse deuten darauf hin, daß die circadianen Rhythmen von Aldosteron und Renin miteinander vergleichbar, jedoch nicht exakt mit dem des Cortisols synchronisiert sind. Unter der Hemmung der ACTH-Freisetzung durch Dexamethason steigt die Reninaktivität an, der Aldosteronspiegel bleibt unverändert. Angiotensinogen und die Angiotensinasen, Parameter, die die aktive Konzentration des Angiotensin II beeinflussen können, scheinen an der Regulation des Aldosterons nicht beteiligt zu sein.Die Ergebnisse wurden auf dem 21. Symposiom der Deutschen Gesellschaft für Endokrinologie und auf dem Symposiom Aktuelle Probleme der Hochdruck- und Nierenkrankheiten anläßlich des 75. Geburtstages von Herrn Prof. Dr. E. Wollheim vorgetragen.  相似文献   
88.
Background: No bariatric operation has been documented to effect adequate weight loss in all patients. Patients with inadequate weight loss or significant weight regain with an anatomically intact short-limb gastric bypass, of which the Fobi pouch operation (FPO) for obesity is a modification, are usually revised to a distal Roux-en-Y gastric bypass (DRYGBP) to enhance weight loss. Method: A retrospective review of the charts of all patients who had a revision to a DRYGBP at our Center during an 8-year period was carried out and the findings analyzed. Results: 65 patients who had the FPO had a revision to the DRYGBP.Most were super obese patients who, even though they had lost significant weight, were still morbidly obese. Some were patients who had not lost adequate weight or <40% excess weight, and a small number were patients who requested more weight loss even though they had a BMI of < 35. 15 patients developed protein malnutrition requiring supplemental feeding. 6 required rerevision to short-limb gastric bypass. Conclusion: Revision of short-limb gastric bypass to DRYGBP usually enhances weight loss but at a cost of an increased incidence of protein malnutrition.  相似文献   
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90.
The clinicopathological associations of 33 singleton infants who died with intraventricular haemorrhage (IVH) without hyaline membrane disease (HMD) ('IVH only') were compared with those of 39 infants who died with IVH+HMD over the same gestation range in order to determine what factors other than those related to HMD may contribute to the pathogenesis of IVH. The incidence of 'IVH only' was inversely related to gestational age in the Hammersmith birth population, whereas the incidence of IVH+HMD rose to a peak at 28-29 weeks' gestation. Infants with 'IVH only' lived longer on average than those with IVH+HMD despite a lower birthweight and shorter gestation. Infants who died in the first 12 hours from 'IVH only' had suffered severe birth asphyxia but in those who died later the main symptom was recurrent apnoea. Fewer infants with asphyxia but in those who died later the main symptom was.recurrent apnoea. Fewer infants with 'IVH only' were given alkali therapy or were connected to the ventilator as compared to those with IVH+HMD, but there were no differences in alkali therapy in those who lived for 12 hours or more. In the 'IVH only' group there was a high incidence of haemorrhage from other sites and of bacterial infections. It is suggested that, in the absence of HMD, extreme immaturity is the main factor determining the occurrence of IVH. Birth asphyxia, apnoeic attacks, haemorrhage, and infections may play subsidiary roles, possibly through development of metabolic acidosis.  相似文献   
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