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51.
We investigated the mutual interactions between hypothalamic norepinephrine (NE) and serotonin (5-HT) in mediating the ACTH and corticosterone responses to direct stimulation of the paraventricular nucleus (PVN) with adrenergic and serotonergic agonists. The hormone responses to the intrahypothalamic injection of the alpha1-adrenergic agonist phenylephrine (20 nmol/2 microl) were significantly reduced by prior depletion of hypothalamic 5-HT with intra-PVN injection of the serotonergic neurotoxin 5,7-dihydroxytryptamine (5,7-DHT), but not after depletion of hypothalamic NE by intra-PVN injection of the noradrenergic neurotoxin 6-hydroxydopamine (6-OHDA). The ACTH and corticosterone responses to intrahypothalamic injection of the 5-HT(1A) receptor agonist 8-OH-DPAT (20 n mol/2 microl) were significantly reduced by depletion of hypothalamic NE with 6-OHDA, but not after depletion of hypothalamic 5-HT with 5,7-DHT. These mutual interactions between the NE and 5-HT neuronal systems, which innervate the PVN, may explain previous findings of equivalent reductions in the hypothalamic-pituitary-adrenal axis responses to neural stimulation after neurotoxic lesioning of either the NE or 5-HT systems.  相似文献   
52.
In the following review we will discuss some familiar drugs with potential use as adjuvant anti-neoplastic agents. We will highlight their unfamiliar property of being able to inhibit matrix metalloproteinase-9 activity, which has recently been proven to play a key role in cancer spread. These drugs' high-safety profile may allow clinicians to construct new anti-cancer protocols that may prove to be less toxic alternatives to those commonly used.  相似文献   
53.
Congenital pseudoarthrosis of the tibia   总被引:2,自引:0,他引:2  
Congenital pseudoarthrosis of the tibia remains one of the most difficult conditions to treat in orthopedic surgery. Seven cases were treated in our hospital by different methods. Three out of seven patients were healed, two of these refractured. At follow-up, the success rate was 14% (one out of seven cases). It is our recommendation that early primary amputation with an appropriate prosthesis should be considered, and that the final evaluation should not be based on obtaining bone union, but on the level of function of the lower extremity.  相似文献   
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Summary The effect of high estrogen doses on weight was studied in 36 adolescent girls with familial tall stature treated to reduce adult height. Mean weight gain during the first year was 9.03.6 kg. Thereafter, there was no or minimal gain on continued treatment. The largest weight velocity occurred during the first 6 months. Within that period, it was most marked during the first 5 weeks, probably due to early water retention. The gain (total, in different groups of patients and in treatment periods of different duration) did not correlate with height and weight before treatment expressed in absolute values or standard deviation scores. It is concluded that the weight gain induced by long-term estrogen treatment cannot be predicted quantitatively before treatment in individuals, and that heavy or fat girls do not necessarily gain more weight than light and lean girls.Abbreviations BA bone age - CA chronologic age - SDS standard deviation score  相似文献   
56.

Background/Purpose

The aim of this report is to assess the technique and outcome of laparoscopic partial nephrectomy in infants and toddlers.

Methods

From January 2001 to January 2005, 7 consecutive patients, ages 5 to 15 months, underwent laparoscopic partial nephrectomies. All patients had duplicated systems associated with ureteroceles (5), severe reflux (1), ectopic ureter (1), and nonfunctioning systems. Follow-up ranged from 4 to 51 months.

Results

All procedures were completed successfully using 4 ports (2 × 5 and 2 × 3 mm) except one, which required an additional port. The distal ureter, renal parenchyma, and hilar vessels were all transected using the harmonic scalpel. The mean operating time was 179 minutes with minimal blood loss in each case. The average hospital stay was 2.4 days (range, 1-5 days). The first case in the series, initially attempted retroperitoneally, was converted to a transabdominal approach because of lack of space. All subsequent approaches were transabdominal. One patient required ureteral stump reexcision because of frequent urinary tract infections associated with a distal ureteral diverticulum.

Conclusions

Laparoscopic partial nephrectomy can be performed safely. The harmonic scalpel divides the parenchyma bloodlessly. The cosmetic result is excellent. A transabdominal approach with division of the ureteral cuff flush with the bladder is recommended.  相似文献   
57.
The "lone" clinical bioethicist working in a large, multisite hospital faces considerable challenges. While attempting to build ethics capacity and sustain a demanding range of responsibilities, he or she must also achieve an acceptable level of integration, sustainability, and accountability within a complex organisational structure. In an effort to address such inherent demands and to create a platform towards better evaluation and effectiveness, the Clinical Ethics Group at the Joint Centre for Bioethics at the University of Toronto is implementing the Hub and Spokes Strategy at seven hospitals. The goal of the Hub and Spokes Strategy is to foster an ethical climate and strengthen ethics capacity broadly throughout healthcare settings as well as create models in clinical bioethics that are excellent and effective.  相似文献   
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Summary Quantitative bone histology was done in undecalcified sections of iliac crest bone specimens obtained from 84 normal American individuals. Samples were obtained within 12 h after death in a vertical and horizontal manner from both the right and left iliac crests. In addition to the determination of normal values of micromorphometric parameters of bone in these healthy American subjects, the following studies were carried out: (a) comparison of variance of micromorphometric parameters of bone obtained from the right versus left iliac bone (40 pairs), (b) comparison of micromorphometric parameters of bone obtained in a vertical versus horizontal manner (12 pairs), (c) evaluation of variance with increasing distance from the compact zone in bone samples obtained in a vertical manner (44 pairs), (d) analysis of variation between bone samples obtained more anteriorly versus posteriorly along the iliac crest (N=40), (e) comparison of differences in micromorphometric parameters obtained from age-matched men versus premenopausal women (N=12), and (f) plotting of histograms for assessment of distribution of micromorphometric parameters. The results show that histomorphometric data of bone cannot be easily compared when different techniques are employed for obtaining bone samples. Sampling variations are kept smaller when bone specimens are obtained in a vertical manner. Anterior/posterior variation does not cause major sampling error. If ranges of variation are taken into account, quantitative bone histology is a valuable tool for assessment of bone structure and bone cells.  相似文献   
60.
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