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41.
Little evidence is available about nurses' use of electronic tools during handoffs. This qualitative study explored information management and use of electronic tools during nursing handoffs. The sample included 93 handoffs by 26 nurses on 5 medical/surgical units in 2 western hospitals with a robust electronic health record (EHR). Data collection included audiotaping handoffs, semi-structured interviews, observations, and fieldnotes. The dataset was inductively coded into 33 categories and 5 themes: good nurse expectations for handoffs, paper forms are best, information at a glance, only pertinent information please, and information tools that work. Two-thirds of the nurses abandoned use of the leadership-endorsed electronic handoff form, preferring personal paper forms. The findings suggest effective electronic solutions will require extensive contextually-based information, information integrated across EHR modules and portable, electronic support throughout shifts. This is a call to action for leaders and informaticists as they select and design future electronic tools.  相似文献   
42.
Expression of acetylcholine receptors (AChRs) in the extrajunctional muscle regions, but not in the neuromuscular junctions, is repressed by propagated electric activity in muscle fibers. During regeneration, subsynaptic-like specializations accumulating AChRs are induced in new myotubes by agrin attached to the synaptic basal lamina at the places of former motor endplates even in the absence of innervation. We examined whether AChRs still accumulated at these places when the regenerating muscles were ectopically innervated and the former synaptic places became extrajunctional. Rat soleus muscles were injured by bupivacaine and ischemia to produce complete myofiber degeneration. The soleus muscle nerve was permanently severed and the muscle was ectopically innervated by the peroneal nerve a few millimeters away from the former junctional region. After 4 weeks of regeneration, the muscles contracted upon nerve stimulation, showed little atrophy and the cross-section areas of their fibers were completely above the range in non-innervated regenerating muscles, indicating successful innervation. Subsynaptic-like specializations in the former junctional region still accumulated AChRs (and acetylcholinesterase) although no motor nerve endings were observed in their vicinity and the cross-section area of their fibers clearly demonstrated that they were ectopically innervated. We conclude that the expression of AChRs at the places of the former neuromuscular junctions in the ectopically innervated regenerated soleus muscles is activity-independent.  相似文献   
43.
Patient care handoffs are cognitively intense activities, especially on medical and surgical units where nurses synthesize information across an average of four to five patients every shift. The objective of this study was to examine handoffs and nurses' use of computerized patient summary reports in an electronic health record after computerized provider order entry (CPOE) was installed. We observed and audio taped 93 patient handoffs on 25 occasions on 5 acute care units in 2 different facilities sharing a vendor's electronic health record. We found that the computerized patient summary report and the electronic health record were minimally used during the handoff and that the existing patient summary reports did not provide adequate cognitive support for nurses. The patient summary reports were incomplete, rigid and did not offer "at a glance" information, or help nurses encode information. We make recommendations about a redesign of patient summary reports and technology to support the cognitive needs of nurses during handoffs at the change of shift.  相似文献   
44.

Aims/hypothesis

Mechanistic target of rapamycin complex 1 (mTORC1) is a master regulator of nutritional status at the cellular and organismic level. While mTORC1 mediates beta cell growth and expansion, its hyperactivation has been observed in pancreatic islets from animal models of type 2 diabetes and leads to beta cell loss. We sought to determine whether such mTORC1 activation occurs in humans with type 2 diabetes or in metabolically stressed human islets and whether mTORC1 blockade can restore beta cell function of diabetic islets.

Methods

Human islets isolated from non-diabetic controls and individuals with type 2 diabetes, as well as human islets and INS-1E cells exposed to increased glucose (22.2 mmol/l), were examined for mTORC1/2 activity by western blotting analysis of phosphorylation of mTORC1 downstream targets ribosomal protein S6 kinase 1 (S6K1), S6 and eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1) and mTORC2 downstream targets Akt and N-myc downstream regulated 1 (NDRG1). mTORC1/2 complexes’ integrity was assessed by immunoprecipitation and subsequent western blot analysis. Cell-type specific expression of activated mTORC1 in human islets was examined by immunostaining of pS6 (Ser 235/236) in human islet sections. Beta cell function was measured by glucose-stimulated insulin secretion (GSIS).

Results

While mTORC2 signalling was diminished, mTORC1 activity was markedly increased in islets from patients with type 2 diabetes and in islets and beta cells exposed to increased glucose concentrations. Under high-glucose conditions in metabolically stressed human islets, we identified a reciprocal regulation of different mTOR complexes, with functional upregulation of mTORC1 and downregulation of mTORC2. pS6 immunostaining showed beta cell-specific upregulation of mTORC1 in islets isolated from patients with type 2 diabetes. Inhibition of mTORC1–S6K1 signalling improved GSIS and restored mTORC2 activity in islets from patients with type 2 diabetes as well as in islets isolated from diabetic db/db mice and mice fed a high-fat/high-sucrose diet.

Conclusions/interpretation

Our data show the aberrant mTORC1 activity in islets from patients with type 2 diabetes, in human islets cultured under diabetes-associated increased glucose conditions and in diabetic mouse islets. This suggests that elevated mTORC1 activation is a striking pathogenic hallmark of islets in type 2 diabetes, contributing to impaired beta cell function and survival in the presence of metabolic stress.
  相似文献   
45.
BACKGROUND: The subject of brain-computer interfaces (BCIs) represents a vast and still mainly undiscovered land, but perhaps the most interesting part of BCIs is trying to understand the information exchange and coding in the brain itself. According to some recent reports, the phase characteristics of the signals play an important role in the information transfer and coding. The mechanism of phase shifts, regarding the information processing, is also known as the phase coding of information. OBJECTIVE: The authors would like to show that electroencephalographic (EEG) signals, measured during the performance of different gripping-force control tasks, carry enough information for the successful prediction of the gripping force, as applied by the subjects, when using a methodology based on the phase demodulation of EEG data. Since the presented methodology is non-invasive it could be used as an alternative approach for the development of BCIs. MATERIALS AND METHODS: In order to predict the gripping force from the EEG signals we used a methodology that uses subsequent signal processing methods: simplistic filtering methods, for extracting the appropriate brain rhythm; principal component analysis, for achieving the linear independence and detecting the source of the signal; and the phase-demodulation method, for extracting the phase-coded information about the gripping force. A fuzzy inference system is then used to predict the gripping force from the processed EEG data. RESULTS: The proposed methodology has clearly demonstrated that EEG signals carry enough information for a successful prediction of the subject's performance. Moreover, a cross-validation showed that information about the gripping force is encoded in a very similar way between the subjects tested. As for the development of BCIs, considering the computational time to pre-process the data and train the fuzzy model, a real-time online analysis would be possible if the real-time non-causal limitations of the methodology could be overcome. CONCLUSION: The study has shown that phase coding in the human brain is a possible mechanism for information coding or transfer during visuo-motor tasks, while the phase-coded content about the gripping forces can be successfully extracted using the phase-demodulation approach. Since the methodology has proven to be appropriate for the case of this study it could also be used as an alternative approach for the development of BCIs for similar tasks.  相似文献   
46.
Microvesicles (MVs) found in peripheral blood are derived from the budding of cell membranes and are associated with a higher risk of thrombosis. Recently, a hypothesis has been suggested that certain plasma proteins could suppress microvesiculation by mediating adhesion of the buds to the mother cell membrane. In a pilot study, we have tested this hypothesis by considering the relation between the amount of MVs in peripheral blood and the ability of plasma to induce adhesion between giant phospholipid vesicles (GPVs). MVs were isolated from human plasma and counted by flow cytometry. The adhesion between GPVs was measured by assessing the average angle of contact between the adhered vesicles. It was found that greater ability of plasma to induce adhesion relates to smaller concentration of MVs in plasma. The ratio between the concentration of MVs and the concentration of platelets proved the most efficient parameter to predict the propensity of the membrane to shed vesicles. Our results indicate that a stronger attractive interaction between GPVs mediated by plasma is associated with a smaller amount of MVs per platelets. Plasma that mediates stronger attractive interaction between GPVs might potentially be associated with a smaller risk of thrombosis.  相似文献   
47.
The effects of intrauterine implantation of 17 beta-estradiol and progesterone on basal and stimulated adenylate cyclase activity in guinea pig myometria were studied in nonpregnant, previously oophorectomized guinea pigs receiving intrauterine implants of either estradiol, progesterone, a combination of the two hormones, or placebo for 7 days. Guanine nucleotides resulted in a significant increase in basal enzymatic activity. The extent of enzymatic stimulation in estradiol-treated animals was significantly higher than that observed in either controls, animals receiving progesterone, or a combination of estradiol and progesterone. Sodium fluoride stimulation occurred in all treatment groups to a similar degree. However, guanine nucleotides resulted in a significant decrease in percent stimulation of maximal sodium fluoride-stimulated enzymatic activity. Finally, beta-adrenergic receptor-mediated enzymatic activity, as assayed by isoproterenol stimulation, was higher in those animals that received estradiol implants than in controls or the other two hormonally treated groups. Intrauterine administration of these sex steroid hormones, directly or indirectly, modulates myometrial adenylate cyclase activity.  相似文献   
48.
BACKGROUND: The Bernese periacetabular osteotomy is used in dysplastic hips to increase the load-bearing area of the hip and to prevent osteoarthritis.The aim of our work was to determine the contact hip stress before and after the osteotomy and to compare the relief of stress with the long-term radiographic and clinical outcome. PATIENTS AND METHODS: We followed 26 dysplastic hips (26 patients) for 7-15 years after the index operation. Clinical evaluation was based on the WOMAC score, osteoarthrosis was evaluated with the T?nnis classification, the angles of lateral (CE) and anterior (VCA) femoral coverage were measured, and biomechanical parameters were studied. RESULTS: Periacetabular osteotomy increased the mean CE from 15 degrees to 37 degrees , and the mean VCA from 22 degrees to 38 degrees . The mean normalized peak contact stress was reduced from 5.2 to 3.0 kPa/N. Four hips required total hip arthroplasty after an average of 4.5 years, 8 hips showed considerable arthrosis progression, and 14 hips had no or mild arthrosis at follow-up. Preoperative WOMAC score, preoperative T?nnis grade and postoperative normalized peak contact stress were the most important predictors of outcome. INTERPRETATION: The Bernese periacetabular osteotomy improves the mechanical status of the hip. Long-term success depends on the grade of arthrosis preoperatively and on the magnitude of operative correction of the contact hip stress.  相似文献   
49.
A case of long diverticular colonic duplication producing acute abdominal pain in a 6-year-old girl is presented. Physical examination showed no signs of acute abdomen at the initial presentation. After a pain-free interval, there was a sudden onset of severe abdominal pain and a large tumor in the lower abdomen was observed. A plain x-ray showed an enormously dilated colonic pouch filled with gas. Excision of the T-shaped duplication and small part of the transverse colon was successful. Because of extensive fibrotic changes in the colon near the opening of duplication, a resection margin of at least 2 cm is recommended.  相似文献   
50.
A genetic network is a formalism that is often used in biology to represent causalities and reason about biological phenomena related to genetic regulation. We present GenePath, a computer-based system that supports the inference of genetic networks from a set of genetic experiments. Implemented in Prolog, GenePath uses abductive inference to elucidate network constraints based on background knowledge and experimental results. Additionally, it can propose genetic experiments that may further refine the discovered network and establish relations between genes that could not be related based on the original experimental data. We illustrate GenePath's approach and utility on analysis of data on aggregation and sporulation of the soil amoeba Dictyostelium discoideum.  相似文献   
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