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81.
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We investigated pS2 and HSP-70 protein expression in 36 pancreatic adenocarcinomas for their effect on disease extent and patient outcome. The cases were reviewed, histologically diagnosed, typed, graded, and staged. Lymphatic vessel, blood vessel and perineural invasion as well as lymph node, resection margin and adjacent organ involvements were re-evaluated. The standard streptavidin biotin immunperoxidase method was used for immunostaining with pS2 and HSP-70 antibodies. Cytoplasmic staining with both antibodies was scored semiquantitatively. The scores were compared with histopathological prognostic parameters using statistical methods. Standard prognostic parameters and staining scores were tested by survival analysis in terms of their effect on survival. All the tumors showed a positive cytoplasmic reaction with HSP-70 antibody. Seventy-seven percent of the tumors showed positive cytoplasmic staining with pS2 antibody (22.2% +, 13.9% ++ and 41.7% +++). There was a statistically significant difference between HSP-70 staining scores with N status and final stages of the tumors (Chi-square, p = 0.03 and p = 0.026, respectively), while neither direct nor inverse correlation was detected for both parameters. PS2 staining scores showed no statistically significant relationship with tumor grade T, M status, perineural invasion, lymph and blood vessel invasion. In tumors with extensive staining with pS2, tumor stage tended to be low (Chi square, p = 0.024, Kendall Tau-b, r: -0.336, p = 0.036). There was a statistically significant difference and inverse correlation between tumors with extensive pS2 staining and tumors with less intense staining in terms of lymph node metastasis (Chi-square, p = 0.041, Kendall Tau: p = 0.024, r = -0,373). In the R0 resection group, in univariate analysis, we found that with higher scores of HSP-70 staining, the prognosis of the patient tended to improve. (Cox regression, p = 0.013). In multivariate analysis, HSP-70 expression was found to be an independent prognostic factor. We found no relationship between pS2 staining and patient survival.  相似文献   
83.
OBJECTIVE: To evaluate the roles of surface electrocardiogram (ECG) and transthoracic echocardiography (ECHO) for prediction of atrial fibrillation (AF) after coronary artery bypass grafting (CABG). METHODS: This study was conducted from 2002-2004 at the Cardiovascular Department of Hacettepe University, Ankara, Turkey. Seventy consecutive patients were enrolled in this study that underwent elective CABG. A 12-lead ECG was recorded one day before cardiac surgery and was repeated during the 5 days after CABG. P-wave dispersion (PWD) was defined as the difference between maximum and minimum P-wave duration. Differences in P-wave duration were compared between the pre- and postoperative 12-lead ECG measurements. RESULTS: Postoperative AF developed in 17 (24%) cases of 70 patients. The PWD was found to be significantly higher in patients with AF preoperatively (60+/-19 versus 47+/-13, p=0.003), postoperative first day (56+/-12 versus 44+/-11, p<0.002) and fifth day (51+/-29 versus 41+/-11, p<0.001). Patients with AF were significantly older, the mean age of the AF group was (68+/-7) years and of the sinus rhythm (SR) group was (59+/-10 years) (p<0.001). The AF group had left ventricular systolic dysfunction (56+/-13% versus 56+/-8%, p=0.042, preoperatively; 49+/-8% versus 60+/-10%, p=0.001, postoperatively) and a larger left atrium (46+/-5 versus 39+/-5 mm, p<0.001, preoperatively and 44+/-7 versus 39+/-5 mm, p=0.046, postoperatively) than the SR group. CONCLUSION: This prospective study demonstrated that PWD on surface ECG and additional echocardiographic parameters are simple and reliable indexes to predict the development of AF after CABG.  相似文献   
84.
Climate change–induced shifts in species phenology differ widely across trophic levels, which may lead to consumer–resource mismatches with cascading population and ecosystem consequences. Here, we examined the effects of different rainfall patterns (i.e., timing and amount) on the phenological asynchrony of population of a generalist herbivore and their food sources in semiarid steppe grassland in Inner Mongolia. We conducted a 10-y (2010 to 2019) rainfall manipulation experiment in 12 0.48-ha field enclosures and found that moderate rainfall increases during the early rather than late growing season advanced the timing of peak reproduction and drove marked increases in population size through increasing the biomass of preferred plant species. By contrast, greatly increased rainfall produced no further increases in vole population growth due to the potential negative effect of the flooding of burrows. The increases in vole population size were more coupled with increased reproduction of overwintered voles and increased body mass of young-of-year than with better survival. Our results provide experimental evidence for the fitness consequences of phenological mismatches at the population level and highlight the importance of rainfall timing on the population dynamics of small herbivores in the steppe grassland environment.

The Earth is facing a great challenge from accelerated climate change. The global surface air temperature has increased by about 1° during the past century and is projected to exceed 1.5 to 2 °C by the end of the 21st century (1). Climate change has caused profound impacts on the Earth’s ecosystems, such as local extinctions (2), range shifts (3), and population fluctuations (4, 5) of many species. Many organisms have advanced the timing of phenological events in response to climate warming, such as earlier leaf-out in plants, earlier emergence of insects, or accelerated egg hatching dates for birds (6). For consumers, phenological events are timed to match peak food resources for breeding; however, the direction of consumer’s phenological response to climate change may differ from the response of species occupying lower trophic levels, leading to asynchrony between resources and consumers (7, 8). With respect to climate change, numerous studies have focused on the impact of temperature and its role in driving phenological asynchrony (911) since this is especially critical for species population dynamics and ecosystem functioning. However, relatively little is known about how rainfall mediates asynchrony between resources and consumers and its potential demographic consequences, especially in arid environments.Shifts in rainfall patterns have been greatly affected by climate warming (12) and play a key role in regulating vertebrate population dynamics (13), the species composition of communities, and ecosystem functions and services (14). Both the timing and the amount of rainfall are recognized as distinct but major components that synergistically influence the timing of vegetation phenology, e.g., the timing of plant germination and seed ripening (15, 16). However, it remains unclear whether changes in the timing or the amount of rainfall play the more dominant role in the processes of phenological asynchrony between interacting species despite their distinct effects on aboveground annual net primary productivity (17). It is therefore important to disentangle the independent effects of rainfall timing and amount if we are to predict responses of species’ populations and ecosystems to global climate change.Among small herbivores, rainfall is well recognized to induce a bottom-up increase in abundance via increasing food availability, as observed in Phyllotis darwini and Octodon degus in South America (18, 19), Pseudomys hermannsburgensis and Mus domesticus in Australia (20, 21), Spermophilus dauricus (22) and Cricetulus barabensis (23) in East Asia, Dipodomys merriami in North America (24), and Mastomys natalensis in Africa (25). However, these observations are all based on the correlation between rodent abundance and precipitation; the mechanism underlying the bottom-up effects of precipitation on rodents through plant productivity is often assumed but has been rarely investigated by manipulative experiments. While valuable in their own right, most previous studies have been unable to elucidate fully the role of rainfall as a potential proximate cue in regulating phenology. In natural environments, many biotic factors (e.g., predation and interspecific competition) and abiotic factors (e.g., flooding of burrows) may interact to influence how phenological processes can affect population dynamics. To understand the effects of rainfall on the role of phenological asynchrony in the population dynamics of target species, including the effects of rainfall amount and timing, it is therefore necessary to exclude or control for confounding factors. Conducting more tightly controlled manipulative experiments is a requirement when assessing the fitness consequences of phenological asynchrony (6, 7), although it is very challenging for small rodents owing to the need for large field enclosures that prevent immigration/emigration of individuals and impacts by predators.We conducted a 10-y, large-scale, manipulative experiment to examine the bottom-up effects of changes in rainfall regime (including timing and amount; SI Appendix, Fig. S1) on the phenological asynchrony between plants and herbivores, demographic parameters, and population dynamics of Brandt’s voles Lasiopodomys brandtii. In our study region in Inner Mongolia, an increase in annual rainfall, especially during the early growing season, can markedly enhance annual net primary productivity (26), with more rain increasing the biomass of rye grass Leymus chinensis (27, 28), a major and favored food source for Brandt’s voles (29). Additional rainfall in the early growing season can provide a match between the peak food resources and peak food requirements of young voles. Therefore, we hypothesized that rainfall would change the population density of voles by mediating the timing and peak amount of preferred foods and that rainfall timing (in the early growing season) would be of vital importance in triggering population increases, or outbreaks, of voles in arid steppe grassland.  相似文献   
85.
Ozturk  Deniz  Araz  Omer  Ucar  Elif Yilmazel  Akgun  Metin 《Sleep & breathing》2018,22(3):769-772
Purpose

Although we spend about one-third of our lives in sleep and recognize its necessity for good health, sleep has only been partially elucidated in the last century. The nasal cycle of congestion and decongestion during sleep has various effects on human physiology. The aim of the present study was to investigate the effect of unilateral forced nostril breathing on sleep.

Methods

Twenty-one healthy male volunteers aged 18–24 years were included in the study. Only individuals with right-hand dominance were included. Subjects were observed during sleep for three nights under different conditions: no obstruction (normal sleep) on the first night, right nasal obstruction on the second night, and left nasal obstruction on the third night.

Results

The main findings of our study are that sleep efficiency, NREM stage III, and total sleep duration were greater during left nasal obstruction (right nostril dominant respiration), while apnea-hypopnea index (AHI), frequency of periodic limb movements, and oxygen desaturation were higher during right nasal obstruction (left nostril dominant respiration).

Conclusion

The nasal cycle has a significant impact on sleep which is reflected in sleep recordings. Our result supports that nasal obstructions, due to deviations, concha hypertrophy, or congestion/decongestion, might affect the physiology of respiration and sleep. Nasal obstruction should be taken into consideration when evaluating patients in sleep laboratories and further studies are required to elucidate the situation in the patients with nasal obstruction.

  相似文献   
86.
PurposeHand-assisted retroperitoneoscopic (HARP) donor nephrectomy prevents major complications, but incision site complications may be more frequent in hand-assisted approach. We evaluated long-term incisional complication rates and cosmetic outcomes after HARP donor nephrectomy in our series.Materials and MethodsA total of 609 donors who underwent nephrectomy between February 2009 and June 2016 were invited for physical examination and face-to-face interview. A total of 209 donors (35.3%) participated to the study. Sex, age, body mass index (BMI), mean follow-up period, incision-related outcomes of cosmesis, and postoperative complications were evaluated. Body image scale (BIS) and cosmetic scale (CS) (scar test) questionnaires were applied. Higher cosmesis and body image scores indicated greater satisfaction.ResultsA total of 191 donors had paramedian (91.4%), and 18 donors had Pfannenstiel incision (8.6%); 121 donors were female (57.9%). The donor mean age and BMI were 49.1 (SD, 1.8) years and 29.7 (SD, 5.1), respectively. Body mass index was significantly lower in the Pfannenstiel group (P < .001). The mean BIS score was 18.9 (SD, 1.8), and the CS questionnaire score was 19.3 (SD, 4,7). The BIS score was significantly better in donors with Pfannenstiel incisions (P < .001), but there was no statistical significance in CS score. The total rate of wound infection was 4.8%, and rate of incisional hernia was 4.8%. The rate of incisional hernia was more frequent in donors with paramedian incision (5.2%), but there was no statistical significance. Six donors (2.9%) required rehospitalization because of incision site complications.ConclusionHand-assisted retroperitoneoscopic donor nephrectomy avoids intra-abdominal complications, but rate of incision site complications can be higher in hand-assisted procedure. The donors were convinced from the cosmetic outcome after HARP donor nephrectomy. The ones who had Pfannenstiel incision had better satisfaction according to BIS score.  相似文献   
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89.

Purpose

Recurrence is a major clinical problem in patients with pulmonary embolism and can affect mortality. The decision to discontinue treatment is important for recurrence and is based on patients’ clinical features as well as certain blood parameters. Our aim in this study was to evaluate whether mean platelet volume (MPV) and platelet distribution width (PDW) have utility as new predictive parameters for recurrence and mortality in pulmonary embolism.

Materials and Methods

A total of 440 patients with pulmonary embolism underwent computed tomography, Doppler ultrasonography, and echocardiography before and at the conclusion of treatment. Thrombocyte count, MPV, PDW, and D-dimer parameters were also evaluated at the same time points.

Results

MPV and PDW were significantly higher in deceased patients (8.8 ± 1.2 fl and 17.4 ± 0.8) compared to surviving patients (7.7 ± 0.9 fl and 17 ± 0.9) (p < 0.0001). Initial MPV and PDW were also significantly higher in patients with recurrence (8.4 ± 0.7 vs 7.6 ± 0.8 fl, p < 0.0001 and 17.3 ± 0.8 vs 16.9 ± 0.9, p = 0.002, respectively) than in patients without recurrence. At the end of treatment, MPV was still higher in patients with recurrence compared to patients without recurrence (8.7 ± 0.5 and 7.5 ± 0.7 fl, respectively, p < 0.0001). MPV values over 8.05 fl at the end of treatment predicted recurrence with 91% sensitivity and 77% specificity.

Conclusion

MPV seems to be an indicator of recurrence in pulmonary embolism and may have utility in the prediction of recurrence. Elevated MPV can also be used to predict mortality in pulmonary embolism.
  相似文献   
90.
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