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51.
The effects of calcitonin gene-related peptide (CGRP) and CGRP 8-37 on the neonatal mouse gubernaculum were examined in organ culture, with the aim of seeing whether CGRP has a direct effect on the gubernaculum. A total of 440 gubernacula were studied. Two hundred and fifty gubernacula were treated with CGRP in concentrations ranging from 0-714 nM/liter. With increasing doses of CGRP the percentage of gubernacula showing vigorous contraction increased from 18-50%. The total percentage of gubernacula showing any form of contraction increased from 76-96%. One hundred and fifty gubernacula were exposed to the CGRP analog CGRP 8-37. Increasing concentrations of CGRP 8-37 from 179-714 nM/liter decreased the rate of vigorous contraction from 18-4%. The percentage of gubernacula showing any degree of contraction decreased from 76-14%. Forty gubernacula removed from testicular feminization (TFM) mice were exposed to varying concentrations of CGRP. In the absence of exogenous CGRP no contractility was observed. By contrast, in the presence of CGRP the gubernacula showed vigorous contractility increasing from 38-90%. The total number of gubernacula showing contraction increased from 75-100%. These studies demonstrated that the neonatal mouse gubernaculum exhibits a high level of endogenous contractility, which can be enhanced in a dose responsive manner with exogenous CGRP. CGRP 8-37 caused a dose responsive inhibition. The androgen-insensitive gubernaculum from the TFM mouse showed no endogenous contraction, but on exposure to CGRP showed an enhanced rate of contractility. These results are consistent with the hypothesis that androgens may control gubernacular migration indirectly via release of CGRP from the genitofemoral nerve in the inguinoscrotal region. The failure of gubernacular motility in vitro and migration in vivo in the TFM mouse may indicate lack of CGRP release from the genitofemoral nerve.  相似文献   
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The diagnosis of teratoma may be made by demonstration of high amylase content in fluid aspirated from anterior mediastinal lesions. In 2 cases of mediastinal teratoma proteolytic enzyme activity was evident at the time of operation. A diagnosis of mediastinal teratoma was aided in 2 subsequent cases by demonstration of elevated amylase activity in the aspirated fluid before definitive operation.  相似文献   
53.
The study reports the pre-post findings from a controlled comparative evaluation of treatments for bulimia nervosa. These pre-post results allow comparison of the hypnobehavioural and cognitive behavioural treatments with a waiting list control group and a comparison of the immediate effects of the two modalities. One hundred and thirty subjects were screened to enter the study. Seventy-eight subjects entered the investigation after being randomly allocated to either a waiting list control group, or to hypnobehavioural or cognitive behavioural groups. The treatments were delivered individually and matched in duration (8 weeks) and the number of sessions. Pre to posttreatment outcome indicated significant differences between the control group and the two treatments in reductions in bulimic behaviours and related eating pathology. The immediate effects of both treatments were equal. There were no differences at posttreatment between the treatments in abstinence from either bingeing or purging. The treatment effects were also similar to the immediate effects obtained by longer therapeutic approaches.  相似文献   
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M Azcue  M Rashid  A Griffiths    P Pencharz 《Gut》1997,41(2):203-208
Background—Malnutrition and growth retardation arecommon complications of Crohn's disease in children. The contributionof resting energy expenditure (REE) to malnutrition is unclear.
Aims—To characterise the REE and body compositionin children with Crohn's disease and compare them with normal controlsand patients with anorexia nervosa; to compare the effects ofprednisolone and enteral nutrition on energy expenditure and body composition.
Subjects—Twenty four children with Crohn'sdisease, 19 malnourished females with anorexia nervosa, and 22 healthycontrol subjects were studied.
Methods—In children with Crohn's diseasemeasurements were done when the disease was acute and repeated at oneand three months after treatment with either prednisolone or enteralnutrition. Resting energy expenditure was measured by indirectcalorimetry and body composition by anthropometry, bioelectricalimpedance analysis, total body potassium,H218O, and bromide space studies.
Results—Body weight and ideal body weight weresignificantly lower in patients with Crohn's disease than in healthycontrols. Lean tissue was depleted and there was an increase inextracellular water. Per unit of lean body mass, there was nodifference between REE in patients with Crohn's disease and controls,whereas patients with anorexia nervosa had significantly reduced REE.With enteral nutrition all body compartments and REE increasedsignificantly (p<0.001). In a subgroup of age-matched men there was asignificant increase in height after three months of enteral nutritioncompared with prednisolone (p<0.01). Those treated with steroids didnot show a significant change in height but did show an increase in allbody compartments. However, intracellular water as well as lean bodymass accretion were significantly higher in the enteral nutrition groupthan in the prednisolone group.
Conclusions—Despite being malnourished, childrenwith Crohn's disease fail to adapt their REE per unit of lean bodymass. This might be a factor contributing to their malnutrition. Lean tissue accretion is higher in patients treated with enteral nutrition than in those treated with prednisolone.

Keywords:Crohn's disease; resting energy expenditure; bodycomposition; anorexia nervosa; prednisolone; enteral nutrition

  相似文献   
57.
Gradient-recalled echo magnetic resonance imaging (GRE MRI), which gives information on blood flow and oxygenation changes (Robinson SP, Howe FA, Griffiths JR 1995, Int J Radiat Oncol Biol Phys 33: 855), was used to observe the responses of six rodent tumour models to carbogen breathing. In one transplanted rat tumour, the Morris hepatoma 9618a, and a chemically induced rat tumour, the MNU-induced mammary adenocarcinoma, there were marked image intensity increases, similar to those previously observed in the rat GH3 prolactinoma. In contrast, the rat Walker carcinosarcoma showed no response. In two mouse tumours, the RIF-1 fibrosarcoma and the human xenograft HT29, carbogen breathing induced a transient fall in signal intensity that reversed spontaneously within a few minutes. The rat GH3 prolactinoma was xenografted into nude mice, and an increase in image intensity was found in response to carbogen, suggesting that any effects that carbogen may have had on the host were not significant determinants of the tumour response. The increases in GRE image intensity of the MNU, H9618a and GH3 tumours during carbogen breathing are consistent with increases in tumour oxygenation and blood flow, whereas the responses of the RIF-1 and HT29 tumours may be the result of a transient steal effect followed by homeostatic correction.  相似文献   
58.
Summary— In the present study we have compared the steady state biopharmaceutic characteristics of four diltiazem once daily controlled release capsules: Mono-Tildiem LP 300® (300 mg), Adizem® XL (300 mg)1, Cardizem® (300 mg) and Dilacor® (240 mg). Sixteen healthy male volunteers (aged 22.9 ± 3.3 years, range 19–31 years) completed an open label, multiple oral dose, randomized, four-period crossover study without a washout period in between. The volunteers received each diltiazem formulation once daily for four days. Trough diltiazem and metabolites plasma concentrations were determined on days 3 and 4. The 24-h plasma concentration-time profiles were assessed after the dose on day 4 of each period. The following steady state pharmacokinetic parameters for diltiazem were calculated: the minimum plasma concentration (cmin), the maximum plasma concentration (cmax), the time to reach that concentration (tmax), the time interval during which the plasma concentration exceeds 50% of cmax (t50), the area under the plasma concentration-time curve (AUC72–96) and the peak-to-trough fluctuation (PTF). For the metabolites of diltiazem, N-mono-desmethyl-diltiazem (NDM) and desacetyldiltiazem (DAD), AUC72–96 (AUCNDM and AUCDAD) and the ratio metabolite/parent compound were calculated. Steady state was achieved on day 3. Except one, all controlled release formulations have satisfactory controlled release properties allowing once daily administration. However, significant (P < 0.05) differences were found between the pharmacokinetic characteristics which do not allow exchange of the various formulations. Concentrations well below 50 ng·mL-1 in the morning hours were observed for Dilacor® (240 mg) and Adizem® XL (300 mg), which could be a disadvantage of these formulations as it is well-known that ischaemic events occur at a higher rate during that part of the day. The plasma concentration profiles of NDM and DAD, the major circulating metabolites, parallel the plasma concentration profiles for the parent compound. From a clinical point of view, all treatments were well tolerated.  相似文献   
59.
A literature search was conducted to identify 'nursing led in-patient units' where the nurse is the designated leader of the clinical team. The review concentrates on studies which have attempted to measure the impact of nursing-led in-patient units and reviews both the methodology and outcomes. Three major bodies of work were identified. Lydia Hall's evaluation of the Loeb Center for Nursing and Rehabilitation (USA) is reviewed in some detail. This work was the model for 'nursing beds' at the two Oxfordshire Nursing Development Units (UK) in the 1980s. Studies evaluating these centres are reviewed and reports of similar UK units discussed. A third body of work evaluates a nurse-managed critical care environment. Common features include a case mix based on nursing need with nurses having authority to admit and discharge patients. While results are generally favourable, with improved patient independence, fewer readmissions, lower mortality and cost savings reported in some or all of the studies, all studies reviewed demonstrate the difficulties of applying an experimental model to real life clinical services. Methodological limitations render firm conclusions difficult. Techniques adopted from studies in field settings, the so-called 'quasi-experiment', are advocated as a remedy, as is further study of the process of care in investigating this model of care delivery.  相似文献   
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