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31.
Cock testes incubated with labeled pregnenolone or progesterone as substrates produced testosterone as the main compound. The formation of 17α-hydroxyprogesterone was greater with progesterone as precursor, but the production of radioactive 20β-dihydroprogesterone and androstenedione was similar with either substrate. Testes from 1-, 21-, and 40-day-old chicks incubated with progesterone as a substrate had a very low testosterone: androstenedione production ratio (0.05). In mature animals, however, more testosterone than androstenedione was produced from radioactive progesterone and the production ratio testosterone: androstenedione was 24.  相似文献   
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Purpose

To investigate whether structured reports (SRs) provide benefits regarding the completeness and the clarity of reports, as well as regarding the satisfaction of the referring physicians compared to narrative freetext reports (NRs) of MRI examinations of the petrous bone.

Methods

After sample size calculation, 32 patients with clinically indicated MRI examinations of the petrous bone were included in this retrospective study. The already existing NRs were taken from the radiologic information system. The corresponding SRs were retrospectively generated by two radiologists using an online-based application. All 64 reports (one NR and one SR per patient) were evaluated by two head and neck physicians using a questionnaire.

Results

While 41% of the SRs showed no missing report key feature, all NRs exhibited at least one missing key feature (p?<?0.001). SRs achieved significantly higher satisfaction rates regarding the linguistic quality and overall report quality compared to NRs: Using a 6-point Likert scale (1?=?insufficient to 6?=?excellent), SRs were rated with a median value of 6 [interquartile range (IQR): 1] for linguistic as well as overall quality, and NRs were rated with a median of 5 (IQR: 0) for linguistic as well as overall quality (p?<?0.001).

Conclusions

Structured reporting of petrous bone MRI examinations may positively influence the completeness and quality of radiologic reports. Due to the easier readability and facilitation of information extraction, SRs improve the satisfaction level of the referring physicians.
  相似文献   
34.
AnaConDa-100 ml (ACD-100, Sedana Medical, Uppsala, Sweden) is well established for inhalation sedation in the intensive care unit. But because of its large dead space, the system can retain carbon dioxide (CO2) and increase ventilatory demands. We therefore evaluated whether AnaConDa-50 ml (ACD-50), a device with half the internal volume, reduces CO2 retention and ventilatory demands during sedation of invasively ventilated, critically ill patients. Ten patients participated in this cross-over protocol. After sedation with isoflurane via ACD-100 for 24 h, the 5-h observation period started. During the first hour, ACD-100 was used; for the next 2 h, ACD-50; and for the last 2 h, ACD-100 was used again. Sedation was titrated to Richmond Agitation and Sedation Scale (RASS) score ??3 to ??4 and a processed electroencephalogram (Narcotrend Index, Narcotrend-Gruppe, Hannover, Germany) was recorded. Minute ventilation, CO2 elimination, and isoflurane consumption were compared. All patients were deeply sedated (Narcotrend Index, mean?±?SD: 38?±?10; RASS scores ??3 to ??5) and breathed spontaneously with pressure support throughout the observation period. Infusion rates of isoflurane and opioid, either remifentanil or sufentanil, as well as ventilator settings were unchanged. Minute ventilation and end-tidal CO2 were significantly reduced with the ACD-50, respiratory rate remained unchanged, and tidal volume decreased by 66?±?43 ml. End-tidal isoflurane concentrations were also slightly reduced while haemodynamic measures remained constant. The ACD-50 reduces the tidal volume needed to eliminate carbon dioxide without augmenting isoflurane consumption.  相似文献   
35.
Recent developments of optogenetic tools and fluorescence-based calcium recording techniques enable the manipulation and monitoring of neural circuits on a cellular level. Non-invasive imaging of brain networks, however, requires the application of methods such as blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI), which is commonly used for functional neuroimaging. While BOLD fMRI provides brain-wide non-invasive reading of the hemodynamic response, it is only an indirect measure of neural activity. Direct observation of neural responses requires electrophysiological or optical methods. The latter can be combined with optogenetic control of neuronal circuits and are MRI compatible. Yet, simultaneous optical recordings are still limited to fiber-optic-based approaches. Here, we review the integration of optical recordings and optogenetic manipulation into fMRI experiments. As a practical example, we describe how BOLD fMRI in a 9.4-T small animal MR scanner can be combined with in vivo fiber-optic calcium recordings and optogenetic control in a multimodal setup. We present simultaneous BOLD fMRI and calcium recordings under optogenetic control in rat. We outline details about MR coil configuration, choice, and usage of opsins and chemically and genetically encoded calcium sensors, fiber implantation, appropriate light power for stimulation, and calcium signal detection, to provide a glimpse into challenges and opportunities of this multimodal molecular neuroimaging approach.  相似文献   
36.
The present study aimed to elucidate the profile of coping in patients with obsessive–compulsive disorder (OCD) in order to discern whether the disorder is characterized by an excess of maladaptive coping skills and/or a lack of adaptive coping skills. Sixty individuals with OCD were compared with 110 individuals with depression and 1050 nonclinical controls on the Maladaptive and Adaptive Coping Styles Questionnaire (MAX). Psychopathology was assessed with the Obsessive–Compulsive Inventory-Revised (OCI-R), the Yale-Brown Obsessive–Compulsive Scale (Y-BOCS), and the Patient Health Questionnaire-9 for depression (PHQ-9). Individuals with OCD and depression displayed more maladaptive coping and avoidance as well as less adaptive coping than nonclinical controls. Importantly, adaptive coping was significantly lower in individuals with OCD than in those with depression at a medium effect size, whereas the clinical groups were indistinguishable on maladaptive coping and avoidance. Lack of adaptive coping was strongly correlated with resistance to symptoms and poor insight in OCD (Y-BOCS), even after controlling for depression. Lack of adaptive coping skills may represent a specific pathogenetic factor in OCD. Longitudinal studies need to clarify whether strengthening adaptive skills during childhood and adolescence may help to prevent the progression from subclinical to manifest OCD.  相似文献   
37.

Background

A multidisciplinary team at a major academic medical center established an Acutely Decompensated Heart Failure Clinical Pathway (ADHFCP) program to reduce inpatient readmission rates among patients with heart failure which, among several interventions, included an immediate consultation from a cardiologist familiar with an ADHFCP patient when the patient presented at the Emergency Department (ED). This study analyzed how that program impacted utilization of services in the ED and its subsequent effect on rates of admission from the ED and on disposition times.

Methods

ADHFCP inpatient visits were retrospectively risk stratified and matched with non-program inpatient visits to create a control group. A Cox survival model analyzed the ADHFCP's impact on patients' likelihood to visit the ED. Multivariable ANOVA evaluated the impact of the program on the patients' likelihood of being admitted when presenting at the ED. The ADHFCP's impact on bed-to-disposition time in the ED was evaluated by Wilcoxon's rank-sum test, as were doses of diuretics administered in the ED.

Results

The survival analysis showed no impact of the ADHFCP on patients' likelihood of visiting the ED, but ADHFCP patients presenting to the ED were 13.1 (95% CI: 3.6–22.6) percentage points less likely to be admitted. There was no difference in bed-to-disposition times, but ADHFCP patients received diuretics more frequently and at higher doses.

Conclusions

Improved communication between cardiologists and ED physicians through the establishment of an explicit pathway to coordinate the care of heart failure patients may decrease that population's likelihood of admission without increasing ED disposition times.  相似文献   
38.
Lichen planus (LP) is a frequent, chronic inflammatory disease involving the skin, mucous membranes and/or skin appendages. Esophageal involvement in lichen planus (ELP) is a clinically important albeit underdiagnosed inflammatory condition. This narrative review aims to give an overview of the current knowledge on ELP, its prevalence, pathogenesis, clinical manifestation, diagnostic criteria, and therapeutic options in order to provide support in clinical management. Studies on ELP were collected using PubMed/Medline. Relevant clinical and therapeutical characteristics from published patient cohorts including our own cohort were extracted and summarized. ELP mainly affects middle-aged women. The principal symptom is dysphagia. However, asymptomatic cases despite progressed macroscopic esophageal lesions may occur. The pathogenesis is unknown, however an immune-mediated mechanism is probable. Endoscopically, ELP is characterized by mucosal denudation and tearing, trachealization, and hyperkeratosis. Scarring esophageal stenosis may occur in chronic courses. Histologic findings include mucosal detachment, T-lymphocytic infiltrations, epithelial apoptosis (Civatte bodies), dyskeratosis, and hyperkeratosis. Direct immuno-fluorescence shows fibrinogen deposits along the basement membrane zone. To date, there is no established therapy. However, treatment with topical steroids induces symptomatic and histologic improvement in two thirds of ELP patients in general. More severe cases may require therapy with immunosuppressors. In symptomatic esophageal stenosis, endoscopic dilation may be necessary. ELP may be regarded as a precancerous condition as transition to squamous cell carcinoma has been documented in literature. ELP is an underdiagnosed yet clinically important differential diagnosis for patients with unclear dysphagia or esophagitis. Timely diagnosis and therapy might prevent potential sequelae such as esophageal stenosis or development of invasive squamous cell carcinoma. Further studies are needed to gain more knowledge about the pathogenesis and treatment options.  相似文献   
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