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41.
Cumulative evidence indicates that song sparrows, Melospiza melodia morphna, of western Washington State prefer territories close to water. Densities of territories were higher within 50m of open water and analysis of stomach contents revealed aquatic organisms. An unusually dry period (less open water) in May and June 1997 had no effect on latency of territorial males to respond to a simulated territorial intrusion (STI), but the number of songs and closest approach to the decoy were lower than those recorded in June 1988 (no major dry periods). A laboratory experiment was conducted in which males and females were exposed to long days to stimulate reproductive development. One group received a bath with water daily and the other group received a dry bath (both groups had ad libitum access to drinking water through a glass tube). Birds with a dry bath tended to show reduced photoperiodically-induced gonadal growth compared with birds that had access to water in the bath. Plasma levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) increased following photostimulation in all groups. However, LH levels were higher in females with access to water. There were no differences in hormone levels in any of the other groups. Taken together these novel data indicate that presence and access to open water could be an important environmental cue for song sparrows in western Washington State. Implications for global climate change and droughts are suggested.  相似文献   
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43.
Recently, nontumor specific circulating DNA was shown to be elevated in a broad range of lymphomas, implicating a role as a potential biomarker. Epstein-Barr virus' (EBV) presence within a proportion of lymphomas implies EBV-DNA has potential as a lymphoma-specific disease response biomarker. However, application would be restricted to EBV-associated lymphomas. Neither detailed comparison has been performed of lymphoma-specific versus nonspecific DNA as disease response biomarkers nor have the kinetics of circulating DNA during treatment been established, and the optimal methodology remains unknown. We prospectively evaluated DNA levels and clinical response of 63 lymphoma patients. DNA was measured in paired serum, plasma, and cell samples at five predetermined time-points taken prior, during and following treatment. Both cell-free (c-f) circulating EBV-DNA (in EBV-associated lymphoma) and nonspecific c-f DNA levels (in all lymphomas) were elevated and discriminatory at presentation compared to healthy controls. Nonspecific c-f DNA was significantly associated with baseline serum lactate dehydrogenase. Within EBV-associated lymphomas at presentation, there was a strong correlation between specific and nonspecific circulating c-f DNA (r = 0.9, P < 0.0001). However, only c-f EBV-DNA correlated with clinical/radiological response. In addition, c-f EBV-DNA, and not nonspecific c-f DNA, provided an early marker of relapsed and refractory disease. Serum versus plasma, and single versus multiple-copy EBV-gene targets were equivalent. Lymphoma-specific DNA is a disease response biomarker; however, nonspecific DNA reflected neither lymphoma-specific DNA nor therapeutic response. Lymphoma disease response can be monitored by blood tests, but new lymphoma-specific biomarkers need to be identified to broaden applicability.  相似文献   
44.
This study evaluated four fluorescent-protein conjugates to monitor microcirculatory variables using the murine cremaster muscle and determined acute and long-term responses to repeated administration of FITC-BSA [conjugated at the University of Sheffield (UoS)] within a dorsal microcirculatory chamber (DMC) in rats. For analysis of the cremaster muscle, male C3H/HeN mice were anaesthetized, the cremaster muscle was exteriorized, then TRITC-BSA, TRITC-dextran, FITC-BSA, FITC-BSA (UoS) or FITC-dextran (0.25 ml/100 g) were administered systemically. The microcirculation was viewed with epi-illumination every 10 min for 120 min. For analysis of the DMC, male Wistar rats were implanted with the chamber. Three weeks later, FITC-BSA (UoS) was administered systemically, and the microcirculation response was monitored using three different protocols. In addition, in vitro stability of fluorescent conjugates was measured over 8 h. With regard to the cremaster muscle, initially no differences in interstitial fluorescence or vessel diameter were observed between the four fluorescent conjugates. By the end of the study, interstitial fluorescence from TRITC-dextran, FITC-dextran and FITC-BSA (Sigma) was significantly (p < 0.05) increased compared to FITC-BSA (UoS). With regard to the DMC, there was no interstitial fluorescence leakage after 180 min or 5 weeks despite repeated administration, but a significant (p < 0.05) leak was detected between 4 and 24 h. FITC-BSA (UoS) was the most stable fluorescent conjugate both in vitro and in vivo and was comparable with other conjugates for evaluating skeletal muscle microcirculation using fluorescent in vivo microscopy.  相似文献   
45.

Introduction and hypothesis

In surgery for pelvic organ prolapse (POP) the use of alloplastic meshes has become common. Among possible complications, mesh exposure is the most frequent problem. It is hypothesized that exposure rates are correlated to mesh weight and the amount of foreign material. Therefore, we conducted a prospective open-label randomized multicenter trial comparing a conventional polypropylene mesh (PP) with a partially absorbable polypropylene mesh (PA) for cystocele treatment.

Methods

A total of 200 patients with POP > stage I were randomized either to a conventional or a partially absorbable mesh. Exposure rates were observed after 3, 12, and 36 months and correlated to mesh material, patient characteristics, intraoperative data, and treatment centers. Furthermore, management of mesh exposure, satisfaction with surgery, and postoperative pain were evaluated.

Results

At all follow-up intervals mesh exposure rate was smaller in the group of the partially absorbable mesh (3 months PP 11.3 % vs PA 3.2 %, p?=?0.0492; 12 months 6.6 % vs 6.3 %; 36 months 7.5 % vs 3.4 %). Over the course of time, mesh exposure was observed in 27 patients, with surgical intervention necessary in 11 patients. The rate of recurrent POP was higher (p?>?0.05) in patients with the partially absorbable mesh. The majority of patients were fully satisfied with the operation (52.8 %) and had no pelvic floor pain (67.5 %).

Conclusion

In this prospective, randomized trial with a long-term follow-up there was a low exposure rate in both treatment groups with a trend toward fewer exposures in the group of the partially absorbable mesh.  相似文献   
46.
We describe “The Lister Technique”—a new 3 step procedure developed in our department for robotic assisted laparoscopic nephroureterectomy (RANU). Our new technique facilitates the complete excision of the whole ureter including ureteric orifice and reduces this risk of tumour spillage from the distal ureter without the need for bivalving the bladder. Our initial data indicates that the technique is associated with reduction in bladder recurrence post-operatively in comparison to current published series. Longer follow up and larger patient numbers are required to validate these results further.  相似文献   
47.
The demand for emergency department (ED) services has increased significantly, due to our increasingly ageing population and limited access to primary care. This article reports outcomes from a transprofessional model of care in an ED in Victoria, Australia. Nurses, physiotherapists, social workers, and occupational therapists undertook additional education to increase the range of services they could provide and thereby expedite patient flow through the ED. One hundred patients who received this service were matched against 50 patients who did not. The most common reasons for patient admission were limb injury/limb pain (n = 47, 23.5%) and falls (n = 46, 23.0%). Transprofessional interventions included applying supportive bandages, slings, zimmer splints and controlled ankle motion (CAM) boots, and referral to new services such as case management and mental health teams. The rate of hospital admissions was significantly lower in the transprofessional group (n = 27, 18.0%) than in the reference group (n = 19, 38%, p = 0.005). This group also had a slightly lower re-presentation rate (n = 4, 2.7%) than patients in the reference group (n = 2, 4.0%). There are many benefits that support this model of care that in turn reduces ED overcrowding and work stress. A transprofessional model may offer a creative solution to meeting the varied needs of patients presenting for emergency care.  相似文献   
48.

Introduction

Complex ventral hernia repair (VHR) is associated with a greater than 30 % wound complication rate. Perfusion mapping using indocyanine green fluorescence angiography (ICG-FA) has been demonstrated to predict skin and soft tissue necrosis in many reconstructive procedures; however, it has yet to be evaluated in VHR.

Methods

Patients undergoing complex VHR involving component separation and/or extensive subcutaneous advancement flaps were included in a prospective, blinded study. Patients with active infection were excluded. ICG-FA was performed prior to incision and prior to closure, but the surgeon was not allowed to view it. An additional blinded surgeon documented wound complications and evaluated postoperative photographs. The operative ICG-FA was reviewed blinded, and investigators were then unblinded to determine its ability to predict wound complications.

Results

Fifteen consecutive patients were enrolled with mean age of 56.1 years and average BMI of 34.9, of which 60 % were female. Most (73.3 %) had prior hernia repairs (average of 1.8 prior repairs). Mean defect area was 210.4 cm2, mean OR time was 206 min, 66.6 % of patients underwent concomitant panniculectomy, and 40 % had component separation. Mean follow-up was 7 months. Two patients developed wound breakdown requiring reoperation, while 1 had significant fat necrosis and another a wound infection, requiring operative intervention. ICG-FA was objectively reviewed and predicted all 4 wound complications. Of the 12 patients without complications, 1 had an area of low perfusion on ICG-FA. This study found a sensitivity of 100 % and specificity of 90.9 % for predicting wound complications using ICG-FA.

Conclusion

In complex VHR patients, subcutaneous perfusion mapping with ICG-FA is very sensitive and has the potential to reduce cost and improve patient quality of life by reducing wound complications and reoperation.
  相似文献   
49.
Aims: An Ecological approach to alcohol behaviour focuses on understanding individual–environment transactions, rather than on cognitive antecedents of behaviour. Meaning exists in the interdependence of individuals and their environments, in terms of affordances. Through subjective experience, this study focussed on group viewpoints related to alcohol-related affordances, or opportunities to consume alcohol in shared drinking environments. Methods: Forty students with a range of self-reported drinking behaviours participated in a Q-Methodology study, ranking 60 statements along a symmetrical grid. This varied concourse of alcohol-related affordances was obtained from a previous observation study within licenced premises and a photo-elicitation interview study with drinkers. Findings: Factor analysis and post-sort interviews revealed four subjective perspectives held by groups about their drinking behaviour: 13 participants were aware of contextual influences, but autonomous in their drinking choices; 12 participants were conscious of influences and compliant to their effects; six participants were unaware of influences, but unanimous with their peers; two participants were concerned about acting appropriately in a context by taking up canonical affordances. Conclusions: Grouping subjectivities from a varied concourse of affordances can reveal subjective experience in relation to drinking environments and alcohol behaviour. This conceptual approach for understanding drinking behaviour should be studied further.  相似文献   
50.

Purpose

The aim of this study was to determine the potential of magnetic resonance imaging to evaluate the biodistribution of exogenous iron within 24 h after one single injection of Venofer® (iron sucrose).

Methods

Venofer® was evaluated in vitro for its ability to generate contrast in MR images. Subsequently, iron disposition was assessed in rats with MRI, in vivo up to 3 h and post mortem at 24 h after injection of Venofer®, at doses of 10- and 40 mg/kg body weight (n?=?2?×?4), or saline (n?=?4).

Results

Within 10–20 min after injection of Venofer®, transverse relaxation rates (R2) clearly increased, representative of a local increase in iron concentration, in liver, spleen and kidney, including the kidney medulla and cortex. In liver and spleen R2 values remained elevated up to 3 h post injection, while the initial R2 increase in the kidney was followed by gradual decrease towards baseline levels. Bone marrow and muscle tissue did not show significant increases in R2 values. Whole-body post mortem MRI showed most prominent iron accumulation in the liver and spleen at 24 h post injection, which corroborated the in vivo results.

Conclusions

MR imaging is a powerful imaging modality for non-invasive assessment of iron distribution in organs. It is recommended to use this whole-body imaging approach complementary to other techniques that allow quantification of iron disposition at a (sub)cellular level.
  相似文献   
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