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71.
The oxidative burst is likely the most rapid defense response mounted by a plant under pathogen attack, and the generated oxidant species may be essential to several subsequent defense responses. In our effort to characterize the signal-transduction pathways leading to rapid H2O2/O2- biosynthesis, we have examined the role of protein phosphorylation in this resistance mechanism. K-252a and staurosporine, two protein-kinase inhibitors, were found to block the oxidative burst in a concentration-dependent manner. When added during H2O2 generation, the burst was observed to rapidly terminate, suggesting that continuous phosphorylation was essential for its maintenance. Importantly, phosphatase inhibitors (calyculin A and okadaic acid) were found to induce the oxidative burst in the absence of any additional stimulus. This may suggest that certain kinases required for the burst are constitutively active and that stabilization of the phosphorylated forms of their substrates is all that is required for burst activity. In autoradiographs of elicited and unstimulated cells equilibrated with 32PO4(3-), several phosphorylated polypeptide bands were revealed that could represent proteins essential for the burst.  相似文献   
72.
A perceived increase in the number of isolates of Moraxella catarrhalis from the respiratory secretions of patients intubated in the pediatric intensive care unit prompted a review of the clinical profiles of such patients and restriction enzyme analysis of the strains involved. Over two months, of 192 patients admitted to the unit, 154 were intubated. Of the 46 for whom endotracheal tube specimens were submitted to the laboratory, M catarrhalis was isolated in 12. M catarrhalis was not felt to be a significant respiratory pathogen by the attending medical staff in any of the patients from whom it was isolated. In only two patients (17%) could nosocomial acquisition be firmly invoked. Restriction enzyme analysis of the 12 strains ruled out the presence of an epidemic strain. Isolation of M catarrhalis from intubated children does not necessarily imply pathogenicity nor an outbreak situation.  相似文献   
73.

Background Population screening for osteoporosis using bone mineral density scan is not feasible in Malaysia as this test is costly. Hence, there is a need to develop a more efficient method to screen for osteoporosis.Objectives To determine the feasibility of an interprofessional collaborative osteoporosis screening programme (IPC-OSP). Methods Postmenopausal women aged?≥?50 years, who had not been diagnosed with osteoporosis were recruited from a primary care clinic from June to August 2014. Patients were assessed for their osteoporosis risk and were counselled on prevention methods. Patients at risk were referred to the doctor with a recommendation for a bone mineral density (BMD) scan. Results Fifty out of 55 patients were recruited (response rate?=?90.9%). A total 26/50 (52.0%) went for a bone mineral density scan, none were osteoporotic, 17/50 (34%) were osteopenic, 2/50 (4.0%), were started on osteoporosis medications and 14/50 (28%) modified their lifestyle to improve bone health or started on calcium supplements. Osteoporosis knowledge significantly increased from baseline to month two (46.3?±?21.4 vs. 79.1?±?14.3, p?<?0.001). Patients had a satisfaction score of 89.8?±?12.4. Follow-up rates were 83.9% and 100% at months 1 (BMD appointment) and 2 (phone follow up), respectively. The intervention was successfully coordinated. Data entry was determined to be viable based on the researchers’ experience. Conclusion The interprofessional collaborative osteoporosis screening programme was found to be feasible in Malaysia.

  相似文献   
74.
ObjectiveTo systematically review health care professionals’ practices and attitudes toward addressing sexuality with people who are living with chronic disease and disability.Data SourcesScopus, PubMed, PsycINFO, Cumulative Index to Nursing and Allied Health, Allied and Complementary Medicine Database, and MEDLINE were searched to August 2020 for English language publications. Reference lists of relevant publications were also searched.Study SelectionEligible studies reported on knowledge, attitudes, and behaviors of health care professionals about addressing sexuality in the context of chronic disease and disability. The search yielded 2492 records; 187 full texts were assessed for eligibility and 114 documents were included (103 unique studies). Study quality was rated using the Mixed Methods Appraisal Tool.Data ExtractionCharacteristics of included studies were recorded independently by 2 authors. Differences were resolved through discussion or by a third author.Data SynthesisA sequential, exploratory mixed studies approach was used for synthesis. Pooled analysis showed that 14.2% (95% CI, 10.6-18.9 [I2=94.8%, P<.001]) of health professionals report routinely asking questions or providing information about sexuality. Professionals reported limited confidence, competence, and/or comfort when initiating conversations about sexuality or responding to patient questions. Sexual rehabilitation typically focused on the effect of disease, disability, and medication on sexual function. Broader dimensions of sexuality were rarely addressed.ConclusionDespite recognizing the value of sexuality to health and well-being, most health professionals regardless of clinical context fail to routinely include assessment of sexuality in their practice. Professionals have limited knowledge and confidence when addressing sexuality and experience significant discomfort when raising this topic with people living with chronic disease and disability. Multicomponent implementation programs are needed to improve health professionals’ knowledge, competence, and comfort when addressing sexuality for people living with chronic disease and disability.  相似文献   
75.

Background

Obesity has reached epidemic proportions in the USA and is a particular threat to those with coronary disease. Motivational interviewing (MI) is a client-centered, directive method for enhancing intrinsic motivation to change by exploring and resolving ambivalence about altering behavior.

Purpose

This study examined the efficacy of MI compared to nutritional counseling for weight loss in a small sample of obese cardiac patients.

Method

Participants were assigned to either MI or to nutrition counseling and followed up over 3 months. Trained undergraduate students delivered the MI intervention.

Results

There were significant reductions in weight in women in the MI intervention, but not in men.

Conclusion

The results suggest that MI may be effective for obese female cardiac patients, in particular, even when delivered by nonprofessional interviewers. Limitations of the study include a small sample size, nonrandomized assignment to conditions, and attrition over time.  相似文献   
76.
77.
78.

Objective:

To evaluate current UK practice of periprocedural haematological management for image-guided procedures in relation to Cardiovascular and Interventional Radiological Society guidelines, which provide recommendations according to bleeding risk of procedures from Category 1 (lowest) to 3 (highest).

Methods:

Survey of practice in UK radiology departments conducted over a 1-year period

Results:

48 radiology departments responded. The percentage of departments that stop antithrombotics pre-procedurally are as follows (for Category 1, 2 and 3, respectively): aspirin (31.3%, 43.8%, 54.2%); clopidogrel (54.2%, 68.8%, 72.9%); therapeutic low-molecular-weight heparin (56.3%, 77.1%, 75.0%). The percentage of departments that perform pre-procedural laboratory testing are as follows (for Category 1, 2 and 3, respectively): international normalized ratio (INR; 81.3%, 95.8%, 93.8%); activated partial thrombin time ratio (APTTR; 60.4%, 75.0%, 93.8%); platelet (77.1%, 91.7%, 95.7%); haemoglobin (70.8%, 85.4%, 87.5%). Mean threshold (standard deviation) of laboratory results for conducting procedures (Level 1, 2 and 3, respectively) are as follows: INR [1.53 (0.197), 1.47 (0.186), 1.47 (0.188)]; APTTR [1.50 (0.392), 1.50 (0.339), 1.48 (0.344)]; platelet count (x103 cells per microlitre) [74.4 (28.7), 79.9 (29.1), 80.5 (29.3)]; haemoglobin (grams per decilitre) [9.05 (1.40), 9.00 (1.33), 8.92 (1.21)]. No department practices conformed to current recommendations for (1) pre-procedural cessation of antithrombotics and (2) pre-procedural laboratory testing. Two (4.2%) department practices conformed to recommendations for thresholds of haematological parameters.

Conclusion:

Current peri-procedural haematological management is variable and often does not conform to existing recommendations. Further research into the impact of this variation in practice on patient outcome is required

Advances in Knowledge:

This study demonstrates wide variation in practice in haematological management for image-guided procedures.Periprocedural haematological management, such as correction of coagulopathy, cessation of antithrombotics and pre-procedural laboratory testing (e.g. for haemoglobin levels and platelet count), is an important consideration for patients undergoing image-guided procedures.1 The challenges of periprocedural haematological management are multifactorial in aetiology. In addition to the increasing range of complex image-guided procedures being performed, the patient population undergoing such procedures may also be complicated.2 Many of these patients have comorbidities requiring antithrombotic therapy, or may have liver and marrow dysfunction, which can affect bleeding risk. Decisions on the optimal periprocedural haematological management are also confounded by the lack of high-level evidence, and existing guidelines within the literature can be variable even for equivalent procedures. For example, in two separate internationally accepted guidelines, the recommended international normalized ratio (INR) for chest drain insertion is <1.5 and <2.0.3,4 There is also limited scope to transfer existing evidence on haematological management from other domains such as open surgery to image-guided interventions. Unlike conventional open surgical procedures where bleeding may be visualized immediately and controlled by direct pressure or vessel ligation, bleeding from image-guided procedures may be difficult to control owing to issues with access and identification.5The lack of high-level evidence is unsurprising, given the potential ethical issues in conducting the necessary studies; it would be difficult to justify the randomization of patients to receiving or not receiving coagulopathy correction prior to undergoing various image-guided procedures for the purpose of research.6 As a result, current evidence is often based on retrospective studies. To address this complex issue, the Society of Interventional Radiology in conjunction with the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) has previously produced guidelines based on existing evidence and expert consensus on periprocedural haematological management for image-guided procedures which are stratified into three categories according to the bleeding risk (4 However, despite the existence of such guidelines, from our experience, significant variation in practice exists between clinicians, even within our own institution.

Table 1.

Society of Interventional Radiology/Cardiovascular and Interventional Radiological Society of Europe consensus guidelines on periprocedural haematological management for image-guided procedures according to category of bleeding risk
Guideline itemGuidance according to category of bleeding risk
 
Category 1 (low risk)Category 2 (intermediate risk)Category 3 (high risk) 
Examples of procedures
 
 VascularVenography, IVC filter, PICC line
Arterial intervention (access size up to 7 French), chemoembolization, uterine fibroid embolizationTIPS 
 Non-vascularThoracentesis, paracentesis, superficial aspiration and biopsy
Intra-abdominal abscess drainage, lung biopsy, percutaneous cholecystostomyRenal biopsy, biliary interventions (new tract), nephrostomy 
Antiplatelet/anticoagulation cessation
 
 Aspirin
Do not withholdDo not withholdWithhold 5-day pre-procedure 
 Clopidogrel
Do not withholdWithhold 5-day pre-procedureWithhold 5-day pre-procedure 
 Therapeutic LMWH
Withhold one-dose pre-procedureWithhold one-dose pre-procedureWithhold for 24 h/up to two doses 
Pre-procedural testing
 
 INR
On warfarin/with liver diseaseAll patientsAll patients 
 APTTR
On unfractionated heparinOn unfractionated heparinOn unfractionated heparin 
 Platelet count
Not routinely recommendedNot routinely recommendedAll patients 
 Haemoglobin
Not routinely recommendedNot routinely recommendedAll patients 
Threshold for correcting parameter/withholding procedure
 
 INR
INR >2.0>1.5 (89% consensus)>1.5 (95% consensus) 
 APTTR
No consensusNo consensus>1.5 times control 
 Platelet count
Transfusion if <50 × 103 μl−1Transfusion if <50 × 103 μl−1Transfusion if <50 × 103 μl−1 
 HaemoglobinNo recommended thresholdNo recommended thresholdNo recommended threshold 
Open in a separate windowAPTTR, activated partial thrombin time ratio; INR, international normalized ratio; IVC, inferior vena cava; LMWH, low-molecular-weight heparin; PICC, peripherally inserted central catheters; TIPS, transjugular intrahepatic portosystemic shunt.Adapted from Patel et al.4The aim of this study was to evaluate current practices of haematological management in patients undergoing image-guided procedures in the UK.  相似文献   
79.
Synthesis of a complementary strand to match the single-stranded, circular, viral (+) DNA strand of phage phi X174 creates a parental duplex circle (replicative form, RF). This synthesis is initiated by the assembly and action of a priming system, called the primosome [Arai, K. & Kornberg, A (1981) Proc. Natl. Acad. Sci. USA 78, 69-73; Arai, K., Low, R. L. & Kornberg, A. (1981) Proc. Natl. Acad. Sci. USA 78, 707-711]. Of the seven proteins that participate in the assembly and function of the primosome, most all of the components remain even after the DNA duplex is completed and covalently sealed. Remarkably, the primosome in the isolated RF obviates the need for supercoiling of RF by DNA gyrase, an action previously considered essential for the site-specific cleavage by gene A protein that starts viral strand synthesis in the second stage of phi X174 DNA replication. Finally, priming of the synthesis of complementary strands on the nascent viral strands to produce many copies of progeny RF utilizes the same primosome, requiring the addition only of prepriming protein i. thus a single primosome, which becomes associated with the incoming viral DNA in the initial stage of replication, may function repeatedly in the initiation of complementary strands at the subsequent stage of RF multiplication. These patterns of phi X174 DNA replication suggest that a conserved primosome also functions in the progress of the replicating fork of the Escherichia coli chromosome, particularly in initiating the synthesis of nascent (Okazaki) fragments.  相似文献   
80.
Myeloma is one of the most common malignancies that results in osteolytic lesions of the spine. Complications, including pathological fractures of the vertebrae and spinal cord compression, may cause severe pain, deformity and neurological sequelae. They may also have significant consequences for quality of life and prognosis for patients. For patients with known or newly diagnosed myeloma presenting with persistent back or radicular pain/weakness, early diagnosis of spinal myeloma disease is therefore essential to treat and prevent further deterioration. Magnetic resonance imaging is the initial imaging modality of choice for the evaluation of spinal disease. Treatment of the underlying malignancy with systemic chemotherapy together with supportive bisphosphonate treatment reduces further vertebral damage. Additional interventions such as cement augmentation, radiotherapy, or surgery are often necessary to prevent, treat and control spinal complications. However, optimal management is dependent on the individual nature of the spinal involvement and requires careful assessment and appropriate intervention throughout. This article reviews the treatment and management options for spinal myeloma disease and highlights the value of defined pathways to enable the proper management of patients affected by it.  相似文献   
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