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91.
K Ojamaa  A Sabet  A Kenessey  R Shenoy  I Klein 《Endocrinology》1999,140(7):3170-3176
Thyroid hormone affects the contractile and electrophysiological properties of the cardiac myocyte that result in part from changes in the expression of thyroid hormone-responsive cardiac genes, including those that regulate membrane ion currents. To determine the molecular mechanisms underlying this effect, expression of a voltage-gated K+ channel, Kv1.5, was measured in response to thyroid hormone. Using quantitative RT-PCR methodology, the content of Kv1.5 messenger RNA (mRNA) in left ventricles of euthyroid rats was 4.25+/-0.6x10(-20) mol/microg total RNA and was decreased by 70% in the hypothyroid rat ventricle to 1.27+/-0.80x10(-20) mol/microg RNA (P<0.01). Administration of T3 to hypothyroid animals restored ventricular Kv1.5 mRNA to control levels within 1 h of treatment, making this the most rapid T3-responsive cardiac gene reported to date. The half-life of Kv1.5 mRNA was 1.9 h and 2.0 h in euthyroid and hypothyroid ventricles, respectively, and T3 treatment of the rats did not alter its half-life. In atrial myocardium, expression of Kv1.5 mRNA (6.10+/-0.37x10(-20) mol/microg RNA) was unaltered by thyroid hormone status. The myocyte-specific and chamber-selective expression of Kv1.5 mRNA was confirmed in primary cultures of rat atrial and ventricular myocytes.  相似文献   
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93.
The plasma concentrations of 3-keto-desogestrel have been measured by radioimmunoassay in a crossover study in nine healthy feamle volunteers given oral desogestrel (150 μg) and ethinyloestradiol (30 μg) and intravenous (i.v.) 3-keto-desogestrel (150 μg) and ethinyloestradiol (30 μg).

Bioavailability ranged between 40.0 and 113% with a mean value (± SD) of 76.1 ± 22.5%. Only 3 subjects had a bioavailability of less than 70%. There was no significant difference in the elimination half life of 3-keto-desogestrel which was 12.6 ± 4.1h following i.v. administration and 11.9 ± 4.1h after oral administration of desogestrel.  相似文献   

94.
Aims and methodsThe aim of this survey was to explore staff attitudes to the indoor smoking ban in a medium secure unit and to ascertain if they had experienced any difficulties in imposing the ban in the four months after its introduction. All staff members available on duty who agreed to participate in the survey were interviewed using a semi-structured questionnaire.ResultsThe response rate was 65%. Sixty-four percent of the staff supported the smoking ban. Forty-three percent reported experiencing patient management problems with the majority complaining of increased patient aggression, increased use of staff time in supervising patients smoking. Additionally, supervising staff were still being exposed to passive smoking. Sixty-five percent reported positive effects due to the ban with the majority reporting that patients were sleeping at night due to the smoking area being closed at night.Clinical implicationsA significant proportion of the staff is still opposed to the smoking ban. Changing staff attitudes through educational programmes will be important in ensuring success of a possible future total ban in psychiatric units.  相似文献   
95.
Concerns,coping and quality of life in head and neck cancer patients   总被引:6,自引:0,他引:6  
This study was conducted to explore the concerns and coping mechanisms used by patients with head and neck cancer and assess their quality of life. A group of 50 consecutive patients with oral and laryngeal cancers were interviewed using a coping and concerns checklist and a semistructured interview proforma to elicit the common concerns in relation to head and neck cancers and their surgical treatment. The Hospital Anxiety and Depression Scale was used to detect anxiety and depression. Concerns were compared between oral and laryngeal cancers and between preoperative and postoperative patients. Commonest concerns were about the future (64%), subjective physical evaluation (60%), finances (56%), being upset (54%), communication (54%), current illness (52%) and inability to do things (50%). The commonest coping mechanisms used were helplessness and fatalism. Resolution was noted in less than 40% of the frequent concerns. As compared to laryngeal cancer patients, those with oral cancer significantly more often had concerns about current illness, subjective evaluation of health, eating and chewing, social interactions, pain and disfigurement (P<0.05). Most subjects had numerous unresolved concerns. Mainly ineffective coping mechanisms such as helplessness and fatalism were employed leading to incomplete resolution. Interventions to minimise these concerns and to handle associated anxiety and depression would improve their quality of life.  相似文献   
96.
The mechanically assisted crevice corrosion performance of head‐neck modular tapers is a significant concern in orthopedic biomaterials. Fretting crevice corrosion processes in modular tapers are thought to be influenced by a wide array of factors including seating mechanics of the junction, hence there is a need for in vitro test methods that can assess their performance. This study presented a test method to directly measure the load‐displacement seating mechanics of modular tapers and used this method to compare the seating mechanics for different tapers, moisture, seating loads and seating rates. Seating mechanics were explored whereby the instantaneous load‐displacement behavior of the head seating onto the neck is captured and used to define the mechanics of seating. Two distinct taper design/material combinations were assembled wet or dry using axially applied loads (500, 1,000, 2,000, and 4,000 N) at two loading rates of 100 and 104 N/s (n = 5 for each condition) using a servohydraulic test frame. The results showed that pull‐off strength scaled with seating load and ranged between 43% and 68% of seating load depending on sample and wetness. Tapers seated wet had higher pull‐off strengths (2,200 ± 300 N) than those seated dry (1,800 ± 200 N, p < 0.05). Seating mechanics (load‐displacement plots) varied due to sample type and due to wetness with differences in seating energy, seating stiffness, and seating displacement. These results show the detailed mechanics of seating during assembly and provide significant insight into the complex interplay of factors associated with even “ideal” seating (axial, quasistatic) loading. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1164–1172, 2018.
  相似文献   
97.
98.
The aim of our study was to determine the clinical course of children with idiopathic childhood nephrotic syndrome (ICNS) who received intravenous methylprednisolone (ivMP) following failure to achieve remission with standard oral prednisolone therapy. This study was designed as a retrospective case record review from 1993 to 2007. Sixteen children received ivMP over the 15-year study period, of whom ten responded, achieving clinical remission. The remaining six children with steroid resistant nephrotic syndrome (SRNS) underwent biopsy [four focal segmental glomerulosclerosis (FSGS), two minimal change disease (MCD)]. Three responders developed late secondary steroid resistance (two FSGS, one MCD). At the latest follow-up (mean 6.7 years), three of the ten ivMP responders and none (0/6) of the children with SRNS had heavy proteinuria and chronic kidney disease (CKD) stage 3-5. The remaining 13 children demonstrated significant steroid dependency but had achieved stable remission following cyclophosphamide and/or ciclosporin therapy. The majority of children with ICNS who do not respond to 4 weeks of daily prednisolone therapy will enter remission following three to five doses of ivMP, thus avoiding a renal biopsy at initial presentation. These children are likely to develop steroid dependency, and the majority will require treatment with alkylating agents and/or ciclosporin to maintain remission. The requirement for ivMP in this setting appears to be associated with a risk of developing CKD in the longer term.  相似文献   
99.
Infections with Entamoeba histolytica are seen worldwide and are more prevalent in the tropics. About 90% of infections are asymptomatic, and the remaining 10% produce a spectrum of clinical syndromes, ranging from dysentery to abscesses of the liver or other organs. Extra-intestinal infection by E. histolytica most often involves liver. Pleuro-pulmonary involvement, seen as the second most common extra-intestinal pattern of infection, is frequently associated with amebic liver abscess. Pulmonary amebiasis occurs in about 2-3% of patients with invasive amebiasis. We report herein the case of a 45-year-old male presenting with hepato-pulmonary amebiasis. The diagnosis was established from direct examination of sputum, in which trophozoites of E. histolytica were detected, and by serology. Following treatment with metronidazole and chloroquine, the clinical evolution improved significantly. On regular follow-up visits, the patient was asymptomatic. This case report reiterates the need for collaboration between clinicians and microbiologists for timely diagnosis of such infections.  相似文献   
100.
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