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61.
A 71-year-old poor surgical candidate with acute calculous cholecystitis was initially managed with cholecystostomy tube drainage for 28 days. He subsequently underwent gallbladder cryoablation under moderate sedation with 3 cryoprobes and 2 separate 10-8-10 freeze-thaw cycles targeting the gallbladder neck/body and fundus followed by cholecystostomy tube removal. He was discharged 1 day after ablation. Magnetic resonance and hepatobiliary iminodiacetic acid scan 1 month postablation demonstrated a thick-walled, distended gallbladder and no filling of the cystic duct. Magnetic resonance 3 months postablation demonstrated retraction of the gallbladder wall with luminal collapse. The patient denied any pain after discharge and is asymptomatic 3 months after ablation.  相似文献   
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63.
The ventrolateral subdivision of the periaqueductal gray (vlPAG) and the adjacent dorsal mesencephalic reticular formation (dMRF) are involved in the modulation of active (rapid eye movement) sleep (AS). In order to determine the effects on AS of the suppression of neuronal activity in these regions, muscimol, a GABA receptor A (GABA(A)) receptor agonist, and bicuculline, a GABA(A) receptor antagonist, were microinjected bilaterally in guinea pigs and the states of sleep and wakefulness were examined. The main effect of muscimol was an increase in AS; this increase occurred in conjunction with a reduction in the time spent in wakefulness. The powerful effect of muscimol was striking especially when considering the small amount of naturally-occurring AS that is present in this species. Additional observable effects that were induced by muscimol were: 1) long lasting episodes of hypotonia/atonia during wakefulness and quiet sleep that included a lack of extensor tone in the hind limbs, and 2) frequently occurring cortical spindles, similar to those observed during naturally-occurring quiet sleep (sleep spindles), that were present during wakefulness. Conversely, bilateral microinjections of bicuculline induced a prolonged state of wakefulness and blocked the effect of subsequent injections of muscimol. These data suggest that endogenous GABA acts on GABA(A) receptors within the vlPAG and dMRF to promote AS in the guinea pig.  相似文献   
64.
Background: Cancer of unknown primary is the fourth most common cause of cancer death in the United Kingdom. National guidance in 2010 recommended the establishment of a dedicated unknown primary team to facilitate targeted investigation and symptom control. A service development project was undertaken to identify those affected by malignancy of unknown origin and institute a pathway for coordinating their care led by a palliative physician.

Method: In order to describe the patient population and illness trajectory and to assess the effect of the new pathway on the clinical outcomes we used a retrospective and prospective comparative case notes survey to identify the pre- and post-pathway population. This took place in secondary care. Inclusion criteria were patients with metastatic disease with no known primary; exclusion criteria were where the site of metastasis was so suggestive of a primary that it would be managed as per that disease process. 88 patients were included.Results: Mean age was 72.5 years. The mean survival time from presentation was 81.8 days. There was no difference pre or during pathway implementation in age, performance status or survival time. There was no reduction in the numbers referred for tumour directed therapy. There was a non-statistically significant reduction in the number who died in hospital during the pathway implementation.

Conclusions: This study suggests having a metastatic malignancy of unknown primary origin service led by a palliative physician does not reduce the number referred for tumour directed therapy. It also adds evidence of the poor prognosis and thus the need for early palliative care input.  相似文献   

65.
In the deficit model approach to clinical evaluation, failures to achieve established academic or clinical standards are attributed to a flawed educational process or, more commonly, to nursing students' personal characteristics. Little is known about the meaning and significance of failing to students. Their perspective is lost among the plethora of clinical-like external criteria that predict the pathway to failure. Not all nursing students can be successful, yet when failure is the outcome, students' dignity, self-worth, and future possibilities must be preserved. Through a Heideggerian interpretative reanalysis of a individual example of an academically successful nursing student who failed clinically, this article discusses the consequences of disconnection in student-faculty relationships. The theme Preserving Personhood: Closing Down on a Future of New Possibilities is presented, as well as two subthemes--Struggling as Adopting a Chameleon Cloak and Struggling as Disconnecting Relations. A deeper understanding of students' clinical failure can help explain why failure, a socially constructed phenomenon, matters to nursing. Relational pedagogical practices to guide clinical educators in helping students at risk of failing are also discussed.  相似文献   
66.
Synthetic cannabinoids are the largest and most structurally diverse class of new psychoactive substances, with manufacturers often using isomerism to evade detection and circumvent legal restriction. The regioisomeric methoxy‐ and fluorine‐substituted analogs of SDB‐006 (N‐benzyl‐1‐pentyl‐1H‐indole‐3‐carboxamide) were synthesized and could not be differentiated by gas chromatography–mass spectrometry (GC–MS), but were distinguishable by liquid chromatography–quadrupole time‐of‐flight–MS (LC–QTOF–MS). In a fluorescence‐based plate reader membrane potential assay, SDB‐006 acted as a potent agonist at human cannabinoid receptors (CB1 EC50 = 19 nM). All methoxy‐ and fluorine‐substituted analogs showed reduced potency compared to SDB‐006, although the 2‐fluorinated analog (EC50 = 166 nM) was comparable to known synthetic cannabinoid RCS‐4 (EC50 = 146 nM). Using biotelemetry in rats, SDB‐006 and RCS‐4 evoked comparable reduction in body temperature (~0.7°C at a dose of 10 mg/kg), suggesting lower potency than the recent synthetic cannabinoid AB‐CHMINACA (>2°C, 3 mg/kg).  相似文献   
67.
68.

Rationale

Δ9-Tetrahydrocannabinol (THC), the main psychoactive constituent of cannabis, accumulates in fat tissue where it can remain for prolonged periods. Under conditions of increased fat utilisation, blood cannabinoid concentrations can increase. However, it is unclear whether this has behavioural consequences.

Objectives

Here, we examined whether rats pre-treated with multiple or single doses of THC followed by a washout would show elevated plasma cannabinoids and altered behaviour following fasting or exercise manipulations designed to increase fat utilisation.

Methods

Behavioural impairment was measured as an inhibition of spontaneous locomotor activity or a failure to successfully complete a treadmill exercise session. Fat utilisation was indexed by plasma free fatty acid (FFA) levels with plasma concentrations of THC and its terminal metabolite (-)-11-nor-9-carboxy-?9-tetrahydrocannabinol (THC-COOH) also measured.

Results

Rats given daily THC (10 mg/kg) for 5 days followed by a 4-day washout showed elevated plasma THC-COOH when fasted for 24 h relative to non-fasted controls. Fasted rats showed lower locomotor activity than controls suggesting a behavioural effect of fat-released THC. However, rats fasted for 20 h after a single 5-mg/kg THC injection did not show locomotor suppression, despite modestly elevated plasma THC-COOH. Rats pre-treated with THC (5 mg/kg) and exercised 20 h later also showed elevated plasma THC-COOH but did not differ from controls in their likelihood of completing 30 min of treadmill exercise.

Conclusions

These results confirm that fasting and exercise can increase plasma cannabinoid levels. Behavioural consequences are more clearly observed with pre-treatment regimes involving repeated rather than single THC dosing.  相似文献   
69.
Vasoactive intestinal polypeptide (VIP)-containing nerves and VIP content of endoscopic rectal biopsies from 47 patients with inflammatory bowel disease and 17 normal controls were examined by immunocytochemistry and radioimmunoassay. Immunocytochemistry revealed a consistent increase in, and abnormal appearance of, VIP nerves in patients with Crohn's disease not only those with rectal involvement but also patients with no histological evidence of rectal disease. Normal control biopsies contained 1.64 +/- 0.39 pmol VIP/mg protein as compared with 3.43 +/- 1.24 pmol VIP/mg protein in tissue from patients with rectal Crohn's disease and 5.37 +/- 1.23 pmol VIP/mg protein in those with Crohn's disease without rectal involvement. Ten of the 17 biopsies examined from ulcerative colitics showed a normal pattern of VIP innervation. Examination of the conventional histology of these biopsies showed that only areas with obvious active proctitis had increased VIP nerves and, unlike the appearance in Crohn's disease, these nerves had a normal morphology. The VIP content of these biopsies was similar to that of the controls; 1.34 +/- 0.37 pmol/mg protein.  相似文献   
70.
A human malignant melanoma cell line (M3Dau) was observed by electron microscopy to interact directly with human platelets and induced platelet aggregation. Fab fragments of a monoclonal antibody MoAb (LYP18), directed against the platelet glycoprotein (GP) IIb-IIIa complex, inhibited platelet-melanoma interactions and platelet-platelet aggregation. M3Dau melanoma cells bind LYP 18 and synthesize IIb-IIIa- like GPs. When the melanoma cells were preincubated with LYP 18, tumor- platelet interaction did not occur, suggesting that the interaction may be mediated by the IIb-IIIa-like GPs present on the melanoma cell surface. Glanzmann's thrombasthenic platelets, lacking GPIIb and IIIa, did not interact with melanoma cells, indicating that the platelet GPIIb-IIIa complex is also necessary for the platelet-melanoma cell interaction. This work demonstrates the importance of the IIb-IIIa-like GPs, present on M3Dau melanoma cells, in mediating tumor-platelet interactions.  相似文献   
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