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71.
Objective: To identify the variables associated with breastfeeding duration.
Data Sources: The health science reference databases of CINAHL, PubMed, and the Cochrane Database of Systematic Reviews.
Study Selection: Meta-analyses, Cochrane reviews, literature reviews, and quantitative and qualitative studies published in English from 1998 through 2008.
Data Extraction: Data included all variables, both positive and negative, that were found to influence the outcome of breastfeeding duration.
Data Synthesis: Demographic factors that influence breastfeeding duration are race, age, marital status, education, socioeconomics, and Special Supplemental Nutrition Program for Women, Infants, and Children status. Biological variables consisted of insufficient milk supply, infant health problems, maternal obesity, and the physical challenges of breastfeeding, maternal smoking, parity, and method of delivery. Social variables included paid work, family support, and professional support. Maternal intention, interest, and confidence in breastfeeding were psychological variables.
Conclusion: Human lactation is a complex phenomena and the duration of breastfeeding is influenced by many demographic, physical, social, and psychological variables.  相似文献   
72.
Dai  CH; Krantz  SB; Zsebo  KM 《Blood》1991,78(10):2493-2497
To understand the factors that regulate the early growth and development of immature erythroid progenitor cells, the burst-forming units-erythroid (BFU-E), it is necessary to have both highly purified target cells and a medium free of serum. When highly purified human blood BFU-E were cultured in a serum-free medium adequate for the growth of later erythroid progenitors, BFU-E would not grow even with the addition of recombinant human interleukin-3 (rIL-3), known to be essential for these cells. However, the addition of recombinant human stem cell factor (rSCF), which supports germ cell and pluripotential stem cell growth, stimulated BFU-E to grow equally well in serum-free as in serum-containing medium. Limiting dilution studies showed that rSCF acts directly on the BFU-E that do not require accessory cells for growth. Furthermore, rSCF was necessary for BFU-E development during the initial 7 days of culture, until these cells reached the stage of the late progenitors, the colony-forming units-erythroid (CFU-E). These studies indicate that early erythropoiesis is dependent on the direct action of SCF that not only affects early stem cells but is continually necessary for the further development of committed erythroid progenitor cells until the CFU-E stage of maturation.  相似文献   
73.
74.

Background

The impact of changing non-verbal consultation behaviours is unknown.

Aim

To assess brief physician training on improving predominantly non-verbal communication.

Design and setting

Cluster randomised parallel group trial among adults aged ≥16 years attending general practices close to the study coordinating centres in Southampton.

Method

Sixteen GPs were randomised to no training, or training consisting of a brief presentation of behaviours identified from a prior study (acronym KEPe Warm: demonstrating Knowledge of the patient; Encouraging [back-channelling by saying ‘hmm’, for example]; Physically engaging [touch, gestures, slight lean]; Warm-up: cool/professional initially, warming up, avoiding distancing or non-verbal cut-offs at the end of the consultation); and encouragement to reflect on videos of their consultation. Outcomes were the Medical Interview Satisfaction Scale (MISS) mean item score (1–7) and patients’ perceptions of other domains of communication.

Results

Intervention participants scored higher MISS overall (0.23, 95% confidence interval [CI] = 0.06 to 0.41), with the largest changes in the distress–relief and perceived relationship subscales. Significant improvement occurred in perceived communication/partnership (0.29, 95% CI = 0.09 to 0.49) and health promotion (0.26, 95% CI = 0.05 to 0.46). Non-significant improvements occurred in perceptions of a personal relationship, a positive approach, and understanding the effects of the illness on life.

Conclusion

Brief training of GPs in predominantly non-verbal communication in the consultation and reflection on consultation videotapes improves patients’ perceptions of satisfaction, distress, a partnership approach, and health promotion.  相似文献   
75.

Background

Chronic pain and its associated distress and disability are common reasons for seeking medical help. Patients with chronic pain use primary healthcare services five times more than the rest of the population. Mindfulness has become an increasingly popular self-management technique.

Aim

To assess the effectiveness of mindfulness-based interventions for patients with chronic pain.

Design and setting

Systematic review and meta-analysis including randomised controlled trials of mindfulness-based interventions for chronic pain. There was no restriction to study site or setting.

Method

The databases MEDLINE®, Embase, AMED, CINAHL, PsycINFO, and Index to Theses were searched. Titles, abstracts, and full texts were screened iteratively against inclusion criteria of: randomised controlled trials of mindfulness-based intervention; patients with non-malignant chronic pain; and economic, clinical, or humanistic outcome reported. Included studies were assessed with the Yates Quality Rating Scale. Meta-analysis was conducted.

Results

Eleven studies were included. Chronic pain conditions included: fibromyalgia, rheumatoid arthritis, chronic musculoskeletal pain, failed back surgery syndrome, and mixed aetiology. Papers were of mixed methodological quality. Main outcomes reported were pain intensity, depression, physical functioning, quality of life, pain acceptance, and mindfulness. Economic outcomes were rarely reported. Meta-analysis effect sizes for clinical outcomes ranged from 0.12 (95% confidence interval [CI] = −0.05 to 0.30) (depression) to 1.32 (95% CI = −1.19 to 3.82) (sleep quality), and for humanistic outcomes 0.03 (95% CI = −0.66 to 0.72) (mindfulness) to 1.58 (95% CI = −0.57 to 3.74) (pain acceptance). Studies with active, compared with inactive, control groups showed smaller effects.

Conclusion

There is limited evidence for effectiveness of mindfulness-based interventions for patients with chronic pain. Better-quality studies are required.  相似文献   
76.

Essentials

  • Inhibitor formation remains a challenging complication of hemophilia A care.
  • The Bethesda assay is the primary method used for determining bleeding risk and management.
  • Antibodies that block factor VIII binding to von Willebrand factor can increase FVIII clearance.
  • Antibodies that increase clearance contribute to antibody pathogenicity.

Summary

Background

The development of neutralizing anti‐factor VIII (FVIII) antibodies remains a challenging complication of modern hemophilia A care. In vitro assays are the primary method used for quantifying inhibitor titers, predicting bleeding risk, and determining bleeding management. However, other mechanisms of inhibition are not accounted for in these assays, which may result in discrepancies between the inhibitor titer and clinical bleeding symptoms.

Objectives

To evaluate FVIII clearance in vivo as a potential mechanism for antibody pathogenicity and to determine whether increased FVIII dosing regimens correct the associated bleeding phenotype.

Methods

FVIII?/? or FVIII?/?/von Willebrand factor (VWF)?/? mice were infused with anti‐FVIII mAbs directed against the FVIII C1, C2 or A2 domains, followed by infusion of FVIII. Blood loss via the tail snip bleeding model, FVIII activity and FVIII antigen levels were subsequently measured.

Results

Pathogenic anti‐C1 mAbs that compete with VWF for FVIII binding increased the clearance of FVIII–mAb complexes in FVIII?/? mice but not in FVIII?/?/VWF?/? mice. Additionally, pathogenic anti‐C2 mAbs that inhibit FVIII binding to VWF increased FVIII clearance in FVIII?/? mice. Anti‐C1, anti‐C2 and anti‐A2 mAbs that do not inhibit VWF binding did not accelerate FVIII clearance. Infusion of increased doses of FVIII in the presence of anti‐C1 mAbs partially corrected blood loss in FVIII?/? mice.

Conclusions

A subset of antibodies that inhibit VWF binding to FVIII increase the clearance of FVIII–mAb complexes, which contributes to antibody pathogenicity. This may explain differences in the bleeding phenotype observed despite factor replacement in some patients with hemophilia A and low‐titer inhibitors.
  相似文献   
77.
78.
OBJECTIVES: To estimate the prevalence of, and identify factors associated with, HIV testing in Britain. DESIGN: A large, stratified probability sample survey of sexual attitudes and lifestyles. METHODS: A total of 12,110 16-44 year olds completed a computer-assisted face-to-face interview and self-interview. Self-reports of HIV testing, i.e. the timing, reasons for and location of testing, were included. RESULTS: A total of 32.4% of men and 31.7% of women reported ever having had an HIV test, the majority of whom were tested through blood donation. When screening for blood donation and pregnancy were excluded, 9.0% of men and 4.6% of women had had a voluntary confidential HIV test (VCT) in the past 5 years. However, one third of injecting drug users and men who have sex with men had a VCT in the past 5 years. VCT in the past 5 years was significantly associated with age, residence, ethnicity, self-perceived HIV risk, reporting greater numbers of sexual partners, new sexual partners from abroad, previous sexually transmitted infection diagnosis, and injecting non-prescribed drugs for men and women, and same-sex partners (men only). Whereas sexually transmitted disease clinics were important sites for VCT, general practice accounted for almost a quarter of VCT. CONCLUSION: HIV testing is relatively common in Britain; however, it remains largely associated with population-based blood donation and antenatal screening programmes. In contrast, VCT remains highly associated with high-risk (sexual or drug-injecting) behaviours or population sub-groups at high risk. Strategies to reduce undiagnosed prevalent HIV infection will require further normalization and wider uptake of HIV testing.  相似文献   
79.
The effects of intravenous verapamil on the electrocardiogram in 15 patients with heart disease in sinus rhythm and in 44 patients with supraventricular and ventricular tachyarrhythmias were evaluated. Verapamil prolonged the P-R interval without effect on the QRS duration or the Q-Tc interval. In patients with atrial flutter and fibrillation, A-V block was increased, with slowing of the ventricular rate, in almost all cases but sinus rhythm was restored in only 1 of 12 patients in atrial fibrillation and in 2 of the 11 patients with flutter. Verapamil had no effect in 3 patients with atrial fibrillation complicating WPW syndrome; in 1 of 5 patients with ventricular tachycardia it caused reversion to sinus rhythm. Sinus rhythm was restored promptly by verapamil in 13 of 17 patients with paroxysmal supraventricular tachycardias; in 2 others, sinus rhythm became established 1 to 2 hours after administration of the drug. Transient hypotension, not requiring treatment, was the only side effect noted but not in the patients with supraventricular tachycardias, in whom blood pressure generally increased after reversion to sinus rhythm by verapamil.  相似文献   
80.
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