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1.
High plasma concentrations of neuropeptide Y (NPY) were found in a patient with bilateral adrenal phaeochromocytomas and medullary thyroid carcinoma associated with MEN IIa (32 pmol/l, normal less than 3.5 pmol/l). Both adrenal tumours contained and secreted NPY. Manipulation at operation produced a remarkable increase in plasma NPY concentrations (peak = 1631 pmol/l) coinciding with increases in plasma levels of catecholamines and arterial pressure. NPY was also shown to be present in thyroid tumour tissue: the concentration of NPY in tumour was 50-fold higher (0.9 nmol/g vs 0.004 nmol/g) than in adjacent normal thyroid tissue. It is possible that NPY from some phaeochromocytomas may contribute to hypertension during surgery.  相似文献   
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The incidence rate of laryngeal papillomas in a Danish subpopulation (approximately 2.8 million inhabitants) was 3.84 × 10-6 per year in the period 1968–1984. For juvenile papillomas the incidence rate was 3.62 × 10-6, compared with 3.94 × 10-6 for laryngeal papillomas of adult onset. When comparing different time periods a significantly low incidence was found in the time 1965–1968, while the incidence remained constant in 1969–1984. The low incidence rate in the early period may be real, but selectional bias may have played a part. It is in general anticipated that maternal genital HPV-infections may serve as an HPV-reservoir, and that juvenile laryngeal papilloma is a result of HPV transmission from the mother to the child during birth. In the period in question cervical HPV-infections have been recorded with increasing frequency in younger women, indicating that the prevalence is rising. However, this is not reflected in the incidence of laryngeal papillomas.  相似文献   
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ABSTRACT The effect of cimetidine (1 g daily) and placebo was studied in a controlled clinical trial comprising 50 patients with non-ulcer dyspepsia in whom an organic abnormality responsible for the dyspeptic symptoms was not disclosed by a standardized and extensive examination programme. Reduction of symptoms occurred in 13 (54%) out of 24 patients treated with cimetidine and in 16 (62%) out of 26 treated with placebo. The difference was insignificant, as were the alterations in the individual dyspeptic symptoms between the groups. Only 6 patients (25%) on cimetidine and 8 (31%) on placebo treatment had a total relief of symptoms. Of these, all cimetidine-treated patients remained free from symptoms during the successive 3-month observation period, while the dyspeptic symptoms relapsed in 3 (38%) placebo-treated patients. Subsequent resumption of placebo treatment reduced the symptoms in all 3 patients, but only one became free from symptoms. Cimetidine does not seem to be superior to placebo in the treatment of non-ulcer dyspepsia in patients without any previous history of ulcer or without any sign on endoscopy of an active or previous ulcer disease.  相似文献   
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ANKE HARTMANN  MD    JENNIFER QUIST  MD    HENNING HAMM  MD    EVA-BETTINA BRÖCKER  MD    PETER FRIEDL  MD  PHD 《Dermatologic surgery》2008,34(7):922-929
BACKGROUND The transplantation of keratinocytes suspended in fibrin carrier represents a candidate regimen for chronic ulcer treatment in an outpatient setting. We evaluated the integration and survival of autologous individualized keratinocytes applied within fibrin matrix onto chronic venous leg ulcers in vivo. Parallel in vitro culture was used to validate keratinocyte survival and apoptosis in fibrin compared to collagen matrix carrier.
METHODS Seven patients with chronic venous leg ulcers were transplanted with autologous keratinocytes suspended in fibrin sealant after isolation and expansion from full-skin biopsy. The fibrin carrier was removed in three patients after 7 days, whereas four patients served as control with fibrin remaining. In parallel in vitro cultures, primary keratinocyte movement in fibrin as well as viability in three-dimensional (3D) fibrin versus collagen lattices was examined.
RESULTS Complete ulcer healing was observed in four of seven ulcers after a mean duration of 14.5 weeks. If the fibrin layer was removed, complete wound healing occurred in three of three patients, compared to one of four in the control group. In vitro, keratinocytes formed a monolayer underneath but remained isolated and nonmobile within the fibrin matrix, suggesting reepithelialization along the lower fibrin interphase. Keratinocyte culture in 3D fibrin at clinically used concentration (90 mg/mL) caused high levels of apoptosis, similar to 3D collagen, which was prevented by diluting fibrin concentration to 3 mg/mL.
CONCLUSIONS Transplantation of autologous keratinocytes suspended in fibrin is efficient in the treatment of chronic venous leg ulcers. Due to an antimigratory and survival-compromising effect, the presently used fibrin carrier should be removed after a few days of transplantation.  相似文献   
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Twenty-three multiprogrammable pacemakers and four implantable cardioverter defibrillators (ICDs) containing either complementary metal-oxide semiconductor (CMOS) or CMOS/Bipolar integrated circuit (IC) technology were exposed to 6-MV photon and 18-MeV electron radiation at various dose levels. Of the 17 pacemakers exposed to photon radiation eight failed before 50 Gy, whereas four of the six pacemakers exposed to electron radiation failed before 70 Gy. Photon scatter doses were well tolerated. For the ICDs detection and charging time increased with accumulated radiation dose, the charging time increased catastrophically at less than 50 total pulses delivered when compared with the charging time of six implanted ICDs. Sensitivity and output energy delivered by the ICD pulse were constant during the test. It was found that devices using the shorter channel length IC technology (i.e., 3 microns CMOS) were per se harder to ionizing radiation than the devices using larger channel length IC technologies (i.e., either 8 microns CMOS or combined 5 microM CMOS/20 V Bipolar). In fact, none of the devices based on 3 microns CMOS IC technology failed before 76 Gy, which is above the highest dose level (70 Gy) normally used in radiation oncology treatments.  相似文献   
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Arrhythmogenic Effects of Quinidine on Catecholamine-induced Delayed Afterdepolarizations. We studied the effects of quinidine and tetrodotoxin (TTX), two drugs that block Na+ channels, on delayed afterdepolarizations (DAD) caused by norepinepbrine in atrial fibers of the canine coronary sinus. At long stimulus cycle lengths of 10 seconds, quinidine increased the amplitude of the afterdepolarizations and caused triggered activity within 1–2 minutes. Simultaneously, action potential duration (APD) was lengthened but upstroke velocity was not decreased. Prolonged exposure to quinidine eventually decreased upstroke velocity but DAD amplitude remained larger than control and triggered activity was still induced more easily. The effects of quinidine to increase afterdepolarizations was partially related to its prolongation of the APD since shortening APD with repolarizing current decreased DAD amplitude. However, DAD amplitude remained larger than control indicating that quinidine caused triggering by other mechanisms as well. TTX, on the other hand, which blocks Na+ channels but shortens APD, decreased DAD amplitude and triggered activity. Part but not all of these effects resulted from the shortening of APD by TTX since prolongation of APD with depolarizing current only partially restored DAD amplitude. Anti-arrhythmic drugs, therefore, may have effects on DADs that partly result from changes in the APD. Quinidine may cause cardiac arrhythmias by virtue of its effects to potentiate triggered activity.  相似文献   
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