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1.
《Endocrine practice》2018,24(12):1023-1029
Objective: The clinical presentation of primary hyperparathyroidism (PHPT) has changed widely in developed countries in the last few decades. We evaluated its variations in our series over a 20-year period (i.e., 1997–2016).Methods: A retrospective survey was conducted in our series of 364 well-characterized consecutive patients, arbitrarily divided into 4 consecutive 5-year periods at diagnosis.Results: In the overall series, only estimated glomerular function (eGFR) and urinary calcium (UCa) showed a significant upward trend (P = .032 and .039, respectively), whereas demographic and clinical characteristics were stable. The UCa upward trend was also confirmed for the subgroup of symptomatic patients (P = .013). No difference was observed in the demographic, clinical, or biochemical characteristics of asymptomatic patients or in the fraction of patients meeting surgical criteria.Conclusion: The clinical presentation of PHPT was stable over 20 years in our large series.Abbreviations: Ca = calcium; eGFR = estimated glomerular filtration rate; 25OHD = 25-hydroxyvitamin D; PHPT = primary hyperparathyroidism; PTH = parathyroid hormone; UCa = urinary calcium  相似文献   

2.
Age trajectories of total mortality represent an irreplaceable source of information about aging. In principle, age affects mortality from all diseases differently than it affects mortality from external causes. External causes (accidents) are excluded here from all causes, and the resultant category “all-diseases” is tested as a helpful tool to better understand the relationship between mortality and age. Age trajectories of all-diseases mortality are studied in the six most populated countries of the South America during 1996–2010. The numbers of deaths for specific causes of death are extracted from the database of WHO, where the ICD-10 revision is used. The all-diseases mortality shows a strong minimum, which is hidden in total mortality. Two simple deterministic models fit the age trajectories of all-diseases mortality. The inverse proportion between mortality and age fits the mortality decreases up to minimum value in all six countries. All previous models describing mortality decline after birth are discussed. Theoretical relationships are derived between the parameter in the first model and standard mortality indicators: Infant mortality, Neonatal mortality, and Postneonatal mortality. The Gompertz model extended with a small positive quadratic element fit the age trajectories of all-diseases mortality after the age of 10 years.  相似文献   

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Objective: To identify research published on obesity in Canada, to explore the range of areas studied, and to identify gaps and areas that merit future research attention. Research Methods and Procedures: Medline and International Pharmaceutical Abstracts databases were searched from 1970 onwards. Original articles were identified and categorized by areas of interest. Results: A total of 1186 relevant articles were identified: 17, 136, 687, and 346 articles during the 1970s, 1980s, 1990s, and 2000 to 2003, respectively. Of the articles, 816 were considered original studies and accepted for this analysis. Twelve research areas were identified: basic science involving animal experiments (29%), human experiments (16%), populations surveys (14%), obesity‐related comorbidities (13%), diagnostic/surgical issues (11%), nonpharmacological approaches (7%), drug‐related issues (4%), anthropometrics (2%), impact of weight loss (2%), cost/healthcare use (1%), attitudes/perceptions (0.9%), and models/procedures (0.5%). Two‐thirds of all research was conducted in Quebec (34%) and Ontario (33%). Discussion: Given the multifactorial nature of obesity, Canadian obesity research covers a broad range of areas with a predominance of basic science but lesser emphasis on community and primary care studies. Furthermore, there was a paucity of research on either clinical management of medical conditions in obese patients or clinical aspects that go beyond weight loss. Thus, although Canada appears well represented in basic research, more attention to exploration of clinical issues and healthcare delivery for obese patients appears warranted.  相似文献   

5.
Limiting the increase in global average temperature to 2 °C is the objective of international efforts aimed at avoiding dangerous climate impacts. However, the regional response of terrestrial ecosystems and the services that they provide under such a scenario are largely unknown. We focus on mountain forests in the European Alps and evaluate how a range of ecosystem services (ES) are projected to be impacted in a 2 °C warmer world, using four novel regional climate scenarios. We employ three complementary forest models to assess a wide range of ES in two climatically contrasting case study regions. Within each climate scenario we evaluate if and when ES will deviate beyond status quo boundaries that are based on current system variability. Our results suggest that the sensitivity of mountain forest ES to a 2 °C warmer world depends heavily on the current climatic conditions of a region, the strong elevation gradients within a region, and the specific ES in question. Our simulations project that large negative impacts will occur at low and intermediate elevations in initially warm‐dry regions, where relatively small climatic shifts result in negative drought‐related impacts on forest ES. In contrast, at higher elevations, and in regions that are initially cool‐wet, forest ES will be comparatively resistant to a 2 °C warmer world. We also found considerable variation in the vulnerability of forest ES to climate change, with some services such as protection against rockfall and avalanches being sensitive to 2 °C global climate change, but other services such as carbon storage being reasonably resistant. Although our results indicate a heterogeneous response of mountain forest ES to climate change, the projected substantial reduction of some forest ES in dry regions suggests that a 2 °C increase in global mean temperature cannot be seen as a universally ‘safe’ boundary for the maintenance of mountain forest ES.  相似文献   

6.
Ecosystems - Climate change is causing a shift to earlier spring budburst in deciduous temperate trees, which may predispose them to greater risk of damage from growing season frosts. Populus...  相似文献   

7.

Introduction

Treatment-related death (TRD) remains a serious problem in small-cell lung cancer (SCLC), despite recent improvements in supportive care. However, few studies have formally assessed time trends in the proportion of TRD over the past two decades. The aim of this study was to determine the frequency and pattern of TRD over time.

Methods

We examined phase 3 trials conducted between 1990 and 2010 to address the role of systemic treatment for SCLC. The time trend was assessed using linear regression analysis.

Results

In total, 97 trials including nearly 25,000 enrolled patients were analyzed. The overall TRD proportion was 2.95%. Regarding the time trend, while it was not statistically significant, it tended to decrease, with a 0.138% decrease per year and 2.76% decrease per two decades. The most common cause of death was febrile neutropenia without any significant time trend in its incidence over the years examined (p = 0.139). However, deaths due to febrile neutropenia as well as all causes in patients treated with non-platinum chemotherapy increased significantly (p = 0.033).

Conclusions

The overall TRD rate has been low, but not negligible, in phase III trials for SCLC over the past two decades.  相似文献   

8.
International Journal of Peptide Research and Therapeutics - PEGylation is a well-known process in the bio-pharmaceutical industry mainly due to its great performance in increasing blood...  相似文献   

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10.
A 30-year continuous record of chlorophyll a samples in May from six locations in the Swedish Lake Mälaren was tested for the correlation to air temperature, water temperature, precipitation, discharge, nutrients, yellow substance, dissolved phosphorous load, ice cover and NAO (North Atlantic Oscillation) index. In the deep basins subjected to stratification chlorophyll a concentration correlated with air temperature with equal or shorter delay than it did in the shallow basins. Both precipitation and discharge were significant negatively correlated with chlorophyll a concentration in many of the basins with varying retention times. However, discharge into flushed basins had a more immediate influence on chlorophyll a concentration, and precipitation was earlier correlated with chlorophyll a concentration in basins fed from the smaller and closer situated catchment.  相似文献   

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Background and Aims:  The prevalence of Helicobacter pylori infection has been decreasing in the USA, but recent data are lacking. This study evaluates the seroprevalence for anti- H. pylori antibodies in symptomatic veterans tested over the past 11 years.
Materials and Methods:  The same serum anti- H. pylori IgG detection system has been used at a tertiary care Veterans Affairs hospital since late 1996. Results of all tests performed from 1997 to 2007 were analyzed.
Results:  Of 7310 unique patients tested, 3982 (54.5%) were positive. Seropositivity declined from 70.8% in 1997 to 48.6% in 2002, then reached a plateau around 50%. A strong birth cohort effect was present, from a seropositivity of 72.7% for the veterans born before 1920 to 22% for those born between after 1980.
Conclusions:  Despite a constant birth cohort effect, H. pylori seropositivity among symptomatic veterans leveled down at ~50% after declining steadily from 1997 to 2002.  相似文献   

13.
《BBA》2014,1837(2):264-269
Photosystem II (PSII) is the pigment–protein complex which converts sunlight energy into chemical energy by catalysing the process of light-driven oxidation of water into reducing equivalents in the form of protons and electrons. Three-dimensional structures from x-ray crystallography have been used extensively to model these processes. However, the crystal structures are not necessarily identical to those of the solubilised complexes. Here we compared picosecond fluorescence of solubilised and crystallised PSII core particles isolated from the thermophilic cyanobacterium Thermosynechococcus elongatus. The fluorescence of the crystals is sensitive to the presence of artificial electron acceptors (K3Fe(CN)3) and electron transport inhibitors (DCMU). In PSII with reaction centres in the open state, the picosecond fluorescence of PSII crystals and solubilised PSII is indistinguishable. Additionally we compared picosecond fluorescence of native PSII with PSII in which Ca2 in the oxygen evolving complex (OEC) is biosynthetically replaced by Sr2 +. With the Sr2 + replaced OEC the average fluorescence decay slows down slightly (81 ps to 85 ps), and reaction centres are less readily closed, indicating that both energy transfer/trapping and electron transfer are affected by the replacement.  相似文献   

14.

Background

Trends in food availability and metabolic risk factors in Brazil suggest a shift toward unhealthy dietary patterns and increased cardiometabolic disease risk, yet little is known about the impact of dietary and metabolic risk factors on cardiometabolic mortality in Brazil.

Methods

Based on data from Global Burden of Disease (GBD) Study, we used comparative risk assessment to estimate the burden of 11 dietary and 4 metabolic risk factors on mortality due to cardiovascular diseases and diabetes in Brazil in 2010. Information on national diets and metabolic risks were obtained from the Brazilian Household Budget Survey, the Food and Agriculture Organization database, and large observational studies including Brazilian adults. Relative risks for each risk factor were obtained from meta-analyses of randomized trials or prospective cohort studies; and disease-specific mortality from the GBD 2010 database. We quantified uncertainty using probabilistic simulation analyses, incorporating uncertainty in dietary and metabolic data and relative risks by age and sex. Robustness of findings was evaluated by sensitivity to varying feasible optimal levels of each risk factor.

Results

In 2010, high systolic blood pressure (SBP) and suboptimal diet were the largest contributors to cardiometabolic deaths in Brazil, responsible for 214,263 deaths (95% uncertainty interval [UI]: 195,073 to 233,936) and 202,949 deaths (95% UI: 194,322 to 211,747), respectively. Among individual dietary factors, low intakes of fruits and whole grains and high intakes of sodium were the largest contributors to cardiometabolic deaths. For premature cardiometabolic deaths (before age 70 years, representing 40% of cardiometabolic deaths), the leading risk factors were suboptimal diet (104,169 deaths; 95% UI: 99,964 to 108,002), high SBP (98,923 deaths; 95%UI: 92,912 to 104,609) and high body-mass index (BMI) (42,643 deaths; 95%UI: 40,161 to 45,111).

Conclusion

suboptimal diet, high SBP, and high BMI are major causes of cardiometabolic death in Brazil, informing priorities for policy initiatives.  相似文献   

15.
The Guayana Shield is one of the oldest geological formations in South America, ranging from southern Colombia, Venezuela, and the Guianas to the extreme north of the Brazilian states of Amazonas and Roraima. Because of its ancient origin and isolation from other mountain ranges in South America, it harbors a rich flora with high levels of endemism. Recent expeditions to remote areas in the Brazilian portion of the Guayana Shield generated many new herbarium collections. Through these efforts, we report the first records for Brazil of 57 species and infraspecific taxa of vascular plants. In most cases, the taxa are narrowly distributed and were previously known from nearby populations in other countries. In other cases, however, the new Brazilian records expand considerably the known geographical distributions of the taxa.  相似文献   

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17.

Background

HIV-1 RNA plasma concentration at viral set-point is associated not only with disease outcome but also with the transmission dynamics of HIV-1. We investigated whether plasma HIV-1 RNA concentration and CD4 cell count at viral set-point have changed over time in the HIV epidemic in the Netherlands.

Methodology/Principal Findings

We selected 906 therapy-naïve patients with at least one plasma HIV-1 RNA concentration measured 9 to 27 months after estimated seroconversion. Changes in HIV-1 RNA and CD4 cell count at viral set-point over time were analysed using linear regression models. The ATHENA national observational cohort contributed all patients who seroconverted in or after 1996; the Amsterdam Cohort Studies (ACS) contributed seroconverters before 1996. The mean of the first HIV-1 RNA concentration measured 9–27 months after seroconversion was 4.30 log10 copies/ml (95% CI 4.17–4.42) for seroconverters from 1984 through 1995 (n = 163); 4.27 (4.16–4.37) for seroconverters 1996–2002 (n = 232), and 4.59 (4.52–4.66) for seroconverters 2003–2007 (n = 511). Compared to patients seroconverting between 2003–2007, the adjusted mean HIV-1 RNA concentration at set-point was 0.28 log10 copies/ml (95% CI 0.16–0.40; p<0.0001) and 0.26 (0.11–0.41; p = 0.0006) lower for those seroconverting between 1996–2002 and 1984–1995, respectively. Results were robust regardless of type of HIV-1 RNA assay, HIV-1 subtype, and interval between measurement and seroconversion. CD4 cell count at viral set-point declined over calendar time at approximately 5 cells/mm3/year.

Conclusion

The HIV-1 RNA plasma concentration at viral set-point has increased over the last decade of the HIV epidemic in the Netherlands. This is accompanied by a decreasing CD4 cell count over the period 1984–2007 and may have implications for both the course of the HIV infection and the epidemic.  相似文献   

18.
The palmitate/Ca2 +-induced (Pal/Ca2 +) pore, which is formed due to the unique feature of long-chain saturated fatty acids to bind Ca2 + with high affinity, has been shown to play an important role in the physiology of mitochondria. The present study demonstrates that the efflux of Ca2 + from rat liver mitochondria induced by ruthenium red, an inhibitor of the energy-dependent Ca2 + influx, seems to be partly due to the opening of Pal/Ca2 + pores. Exogenous Pal stimulates the efflux. Measurements of pH showed that the Ca2 +-induced alkalization of the mitochondrial matrix increased in the presence of Pal. The influx of Ca2 + (Sr2 +) also induced an outflow of K+ followed by the reuptake of the ion by mitochondria. The outflow was not affected by a K+/H+ exchange blocker, and the reuptake was prevented by an ATP-dependent K+ channel inhibitor. It was also shown that the addition of Sr2 + to mitochondria under hypotonic conditions was accompanied by reversible cyclic changes in the membrane potential, the concentrations of Sr2 + and K+ and the respiratory rate. The cyclic changes were effectively suppressed by the inhibitors of Ca2 +-dependent phospholipase A2, and a new Sr2 + cycle could only be initiated after the previous cycle was finished, indicating a refractory period in the mitochondrial sensitivity to Sr2 +. All of the Ca2 +- and Sr2 +-induced effects were observed in the presence of cyclosporin A. This paper discusses a possible role of Pal/Ca2 + pores in the maintenance of cell ion homeostasis.  相似文献   

19.
Obesity and diabetes have been associated with increased consumption of highly processed foods, and reduced consumption of whole grains and nuts. It has been proposed, mainly on the basis of observational studies, that nuts may provide superior satiation, may lead to reduced calorie consumption, and may decrease the risk of type 2 diabetes; but evidence from randomized, interventional studies is lacking. A total of 20 men and women with the metabolic syndrome participated in a randomized, double‐blind, crossover study of walnut consumption. Subjects had two 4‐day admissions to the clinical research center where they were fed an isocaloric diet. In addition, they consumed shakes for breakfast containing either walnuts or placebo (shakes were standardized for calories, carbohydrate, and fat content). Appetite, insulin resistance, and metabolic parameters were measured. We found an increased level of satiety (overall P value = 0.0079) and sense of fullness (P = 0.05) in prelunch questionnaires following the walnut breakfast as compared to the placebo breakfast, with the walnut effect achieving significance on day 3 and 4 (P = 0.02 and P = 0.03). We did not find any change in resting energy expenditure, hormones known to mediate satiety, or insulin resistance when comparing the walnut vs. placebo diet. Walnut consumption over 4 days increased satiety by day 3. Long‐term studies are needed to confirm the physiologic role of walnuts, the duration of time needed for these effects to occur, and to elucidate the underlying mechanisms.  相似文献   

20.
1. In previous work, phytoplankton regulation in freshwater lakes has been associated with many factors. Among these, the ratio of total nitrogen to total phosphorus (TN : TP) has been widely proposed as an index to identify whether phytoplankton are N‐ or P‐limited. From another point of view, it has been suggested that planktivorous fish can be used to control phytoplankton. 2. Large‐scale investigations of phytoplankton biomass [measured as chlorophyll a, (chl‐a)] were carried out in 45 mid‐lower Yangtze shallow lakes to test hypotheses concerning nutrient limitation (assessed with TN : TP ratios) and phytoplankton control by planktivorous fish. 3. Regression analyses indicated that TP was the primary regulating factor and TN the second regulating factor for both annual and summer phytoplankton chl‐a. In separate nutrient–chl‐a regression analyses for lakes of different TN : TP ratios, TP was also superior to TN in predicting chl‐a at all particular TN : TP ranges and over the entire TN : TP spectrum. Further analyses found that chl‐a : TP was not influenced by TN : TP, while chl‐a : TN was positively and highly correlated to TP : TN. 4. Based on these results, and others in the literature, we argue that the TN : TP ratio is inappropriate as an index to identify limiting nutrients. It is almost impossible to specify a ‘cut‐off’ TN : TP ratio to identify a limiting nutrient for a multi‐species community because optimal N : P ratios vary greatly among phytoplankton species. 5. Lakes with yields of planktivorous fish (silver and bighead carp, the species native to China) >100 kg ha?1 had significantly higher chl‐a and lower Secchi depth than those with yields <100 kg ha?1. TP–chl‐a and TP–Secchi depth relationships are not significantly different between lakes with yields >100 kg ha?1 or <100 kg ha?1. These results indicate that the fish failed to decrease chl‐a yield or enhance ZSD. Therefore, silver carp and bighead carp are not recommended as a biotic agent for phytoplankton control in lake management if the goal is to control the entire phytoplankton and to enhance water quality.  相似文献   

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