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91.
(1) Sexually immature and mature rats were fed a nutritionally-completeliquid diet or isovolumetric quantities of the same diet inwhich 36% of the calories as glucose were substituted by isocaloricethanol. (2) After 6 weeks ethanol feeding, significant reductionsin body weight (approx. 15%) occurred in both groups of rats.In immature rats there were significant reductions (7–21%)in bone, gastrocnemius, liver, and skin weights. The total skeletalmuscle mass was reduced by 20%. Lung and kidney weights werenot significantly altered. In mature rats smaller decreasesin organ weights were found, which were only significant forskeletal muscle and skin. The gastrocnemius protein contentwas significantly reduced in immature but not in mature rats.Plasma protein concentrations were unaltered in both groups.(3) Plasma aspartate aminotransaminase, glutamyl transferaseand creatine kinase activities in immature and mature rats werenot significantly altered by ethanol feeding, but there wereincreases in plasma alkaline phosphatase activities in immature,but not in mature, rats. Plasma glucose was slightly raisedby ethanol feeding in immature but not mature rats. Plasma triglyceridesand insulin were unaltered in both groups of rats. (4) Proteinsynthesis was measured with a flooding dose of L[43H]-phenylalanine.Rates of protein breakdown were calculated from the differencebetween synthesis and growth. Fractional and absolute ratesof skeletal muscle protein synthesis were reduced by 13–30%by ethanol treatment, in immature and mature rats. Fractionalrates of protein breakdown were also reduced by ethanol, by13 and 19% in immature and mature rats, respectively.  相似文献   
92.
BACKGROUND/OBJECTIVE Although the alexandrite 755-nm-wavelength laser is effective in the treatment of unwanted hair, there are no published studies gauging the efficacy of the variable long-pulse alexandrite laser in the treatment of superficial pigmented lesions.
STUDY DESIGN/METHODS Eighteen patients underwent a single treatment session using a variable pulse-width alexandrite laser. Test sites were performed using a 10-mm spot size and up to four pulse widths (3, 20, 40, 60 ms) with and without epidermal cooling. Full treatments were performed 3 weeks later using optimum test parameters. The patients were evaluated at 3 and 6 weeks.
RESULTS Patients with darker lentigines had greater lesion clearance than those patients with lighter colored lentigines. Shorter pulse widths and treatment without cryogen cooling both, independently, lowered the fluence threshold for lentigo clearance.
CONCLUSION A long-pulse alexandrite laser is effective in clearing solar lentigines in a single pass with minimal adverse effects.  相似文献   
93.
BACKGROUND: Mohs micrographic surgery (MMS) offers high cure rates and maximum tissue preservation in the treatment of more common cutaneous malignancies, but its effectiveness in rare aggressive tumors is poorly defined. OBJECTIVE: Evaluate the effectiveness of MMS in the treatment of six rare aggressive cutaneous malignancies as seen by Mohs surgeons working at a referral center. METHODS: Retrospective chart review of 26,000 cases treated with MMS at the Geisinger Medical Center Department of Dermatology during a 16-year period with the following diagnoses: poorly differentiated squamous cell carcinoma (PDSCC), dermatofibrosarcoma protuberans (DFSP), microcystic adnexal carcinoma (MAC), extramammary Paget's disease (EMPD), Merkel cell carcinoma (MCC), and sebaceous carcinoma (SEB CA). Patient demographic data, tumor measurements, treatment characteristics, and marginal recurrence rates were compiled and evaluated. RESULTS: The mean numbers of cases identified per year for each tumor type were as follows: PDSCC, 6.19; DFSP, 2.44; MAC, 1.63; and EMPD, 0.63. For PDSCC, 85 cases were available for follow-up with a local recurrence rate of 6% at a mean follow-up time of 45 months. For DFSP, there were 35 cases with no local recurrence at a mean follow-up of 39 months. For MAC, there were 25 cases with a local recurrence rate of 12% at a mean follow-up of 39 months. For EMPD, there were 10 cases with no local recurrences at a mean follow-up of 34 months. CONCLUSIONS: Collectively, our data on PDSCC, DFSP, MAC, and EMPD, combined with other studies in the literature, show that MMS is the most effective therapy for these rare aggressive cutaneous malignancies.  相似文献   
94.
Ten patients underwent implantation of a rate adaptive ventricular pacing system with a new pulse generator and lead. The unipolar lead has a steroid eluting tip and a pressure sensor. The first derivative of the signal from this sensor, dP/dt, is determined and the pacemaker rate is varied in response to changes in the right ventricular dP/dtMAX. During implantation, dP/dt values were in the range of 180-720 mm Hg/sec. The autothreshold for pacing at 2.5 V remained unchanged 1 month after implantation (0.065 +/- 0.045 msec, range 0.05-2.00 msec) and only slightly increased after 3 months (0.075 +/- 0.045 msec, range 0.05-2.00 msec). A significant correlation existed between the dP/dt measured during implantation and the right ventricular pressure measured by telemetry at follow-up visits (r = 0.93, P = 0.0001). Initial pacemaker programming was performed on the second day after implantation following a short walk and was adjusted subsequent to follow-up visits according to the patient's subjective assessment and in accordance with the results of exercise tests and Holter monitoring. Exercise and Holter tests did not significantly change initial programming. There was a significant correlation between right ventricular systolic pressure and the rate response setting (r = -0.66, P less than 0.05). During dP/dt pacing, all patients felt well, and eight of these reported an improvement compared to nonrate adaptive pacing. The heart rate response to effort and recovery was appropriate. It was concluded that: (1) right ventricular dP/dt is a suitable parameter for controlling the pacing rate; (2) appropriate programming of the dP/dt pacemaker results in a suitable heart rate response to exercise and recovery.  相似文献   
95.
A high incidence of sudden death due to ventricular fibrillation (VF) has been observed in dogs under chronic treatment with probucol, a new hypocholesterolemic agent. The present study describes the cardiac electrophysiologic properties of probucol-treated dogs and characterizes the electrophysiological response of these animals to manipulation of the autonomic nervous system. There was no significant difference in the spontaneous sinus cycle length, the QT interval, refractory period of the atrium, ventricle or A-V junction between normal and probucol-treated dogs. Epinephrine produced VF with few and sometimes no preceding premature ventricular extrasystoles. Electrical stimulation of the stellate ganglion induced VF in 16/19 dogs whereas stimulation of the right stellate ganglion induced VF in 1/19 dogs. Phenylephrine induced VF in 0/19 dogs, isoproterenol in 5/19 dogs, but phenylephrine + isoproterenol induced VF in 9/11 dogs in which isoproterenol did not produce VF. alpha (phentolamine) or beta (propranolol) blockade prevented initiation of VF by epinephrine, phenylephrine + is isoproterenol, and left stellate stimulation but alpha blockade did not prevent induction of VF by isoproterenol when isoproterenol alone produced VF. In this nonischemic model, we conclude that left stellate stimulation is a far more potent initiator of VF than right stellate stimulation and that induction of VF appears to require both alpha and beta adrenergic receptor stimulation.  相似文献   
96.
97.
Parent, Peer and Personal Determinants of Adolescent Drinking   总被引:4,自引:1,他引:4  
This study examined direct and indirect influences of parents and peers on adolescent drinking. One hundred and six adolescents, their parents and a same-sex best friend of the adolescent each completed measures that tapped actual and perceived drinking behaviour, and normative standards for alcohol use. Of methodological interest was that adolescents of both sexes provided accurate reports of their parents' and peer's drinking, as well as drinking norms. Path analyses revealed different effects for male and female adolescents. Strongest predictors of alcohol use for males were their perceptions of their father's and mother's drinking, and their father's actual drinking. Best friend's drinking was positively related to the adolescent males' perceptions of themselves as a drinker. The single predictor of their internalized norms was the perception adolescent males had of their friend's drinking. Significantly, the adolescent male's own norms predicted how much and what they drank. For adolescent females, how much they believed their best friend drank, and their friend's normative standards, were the strongest predictors of alcohol use. Father's drinking also influenced the drinking practices of daughters, but mothers had no impact on their daughters' alcohol use. In contrast to young males, females' personal preferences or liking of alcohol successfully predicted most of their drinking behaviour.  相似文献   
98.

Objective

The origin of the side branch (SB) is the most common site for restenosis in coronary bifurcations. The end‐point is to compare the results of SB dilation with drug‐eluting balloon (DEB group) versus conventional balloon (BAL group) in bifurcations treated with provisional T stenting.

Methods and Results

Each group included 50 patients. In DEB, the origin of SB was dilated with a Sequent® Please balloon. In both groups, a Taxus Liberté® stent was implanted in the main vessel, with kissing balloon postdilation. If the outcome for the SB was suboptimal, a Taxus stent was implanted in BAL and a bare stent in DEB group. An angiographic follow‐up and IVUS were scheduled for 12 months later. Adverse events (MACE) were 24% in BAL versus 11% in DEB (P = 0.11), with greater revascularization (TLR) in the BAL group (22% vs. 12%, P = 0.16). At angiographic follow‐up, there was a lower percentage of SB restenosis in the DEB group (20% vs. 7%, P = 0.08), with less late loss (0.40 mm vs. 0.09 mm, P = 0.01).

Conclusion

Side branch dilation with a drug‐eluting balloon resulted in better angiographic outcomes than with a conventional balloon, with less late loss and restenosis at the 12‐month follow‐up. (J Interven Cardiol 2013;26:454‐462)
  相似文献   
99.

Purpose

We evaluate the use of finasteride to control gross hematuria secondary to prostatic bleeding.

Materials and Methods

We reviewed retrospectively 42 patients treated with finasteride to treat gross hematuria.

Results

There were 28 evaluable patients who had taken finasteride for at least 6 months to control gross hematuria and hematuria ceased in 25 (91%). In 1 patient clot retention developed requiring transurethral resection of the prostate and 2 patients had 1 or more minor episodes of bleeding that resolved spontaneously.

Conclusions

Finasteride appears to be an effective agent for controlling gross hematuria secondary to prostatic bleeding.  相似文献   
100.
The cutaneous circulation is thought to participate in the neurocirculatory adjustments during orthostatic stress, but the underlying mechanisms mediating such reflex cutaneous vasoconstriction are poorly understood. The aim of this study was to assess the relative importance of baroreceptor (cardiopulmonary and arterial) and positional (vestibular, exercise, veno-arteriolar and myogenic) reflexes in triggering cutaneous vasoconstriction during upright posture. First, hypotensive lower body negative pressure (LBNP) was compared with actual postural changes to assess the relative contributions of baroreceptor reflexes and positional reflexes. Then changes in body position were compared with changes in limb position in the absence or presence of proximal (axillary) or distal (local cutaneous) nerve blocks, to assess the relative contributions of vestibular, exercise, veno-arteriolar and myogenic reflexes. Skin sympathetic nerve activity was determined by microneurography, and skin blood flow was determined by laser Doppler velocimetry. LBNP of –50 mmHg (cardiopulmonary + arterial baroreceptors) had no effect on skin sympathetic nerve activity or skin vascular resistance. In contrast, an upright posture with the arms dependent (baroreceptor+vestibular+exercise+veno-arteriolar reflexes) caused a two- to threefold increase in skin vascular resistance. In the supine position, passive movement of the arm into a dependent position to activate veno-arteriolar reflexes alone evoked an increase in skin vascular resistance which approximated the response to normal upright posture. Blocking central sympathetic nerve impulses by application of an axillary blockade did not influence the cutaneous vasoconstrictor response to an upright posture or changes in limb position. In contrast, application of a distal nerve block by local cutaneous surface anaesthesia completely blocked vasoconstrictor responses evoked by these manoeuvres. In conclusion, these experiments in human subjects identify a primary role for veno-arteriolar reflexes in triggering vasoconstriction in the cutaneous circulation during upright posture.  相似文献   
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