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1.

Background

We evaluated whether menstrual cycle phase influences the assessment of tubal patency by hysterosalpingography (HSG) in baboons.

Methods

Retrospective analysis of baseline tubal patency studies and serum estradiol (E2) and progesterone (P4) values obtained from female baboons used as models for development of non‐surgical permanent contraception in women. The main outcome measure was bilateral tubal patency (BTP) in relationship with estradiol level.

Results

Female baboons (n = 110) underwent a single (n = 81), two (n = 26), or three (n = 3) HSG examinations. In 33/142 (23%) HSG examinations, one or both tubes showed functional occlusion (FO). The median E2 in studies with BTP (49 pg/mL) was significantly higher than in those studies with FO (32 pg/mL, P = .005). Among 18 animals with repeat examinations where serum E2 changed from <60 to ≥ 60 pg/mL, 13 results changed from FO to BTP (P = .0001). No sets showed a change from BTP to FO with an increase in estradiol.

Conclusion

In baboons, functional occlusion of the fallopian tube is associated with low estradiol levels, supporting a role for estrogen‐mediated relaxation of the utero‐tubal junction.  相似文献   

2.

Aim

Land use is the most pervasive driver of biodiversity loss. Predicting its impact on species richness (SR) is often based on indicators of habitat loss. However, the degradation of habitats, especially through land-use intensification, also affects species. Here, we evaluate whether an integrative metric of land-use intensity, the human appropriation of net primary production, is correlated with the decline of SR in used landscapes across the globe.

Location

Global.

Time period

Present.

Major taxa studied

Birds, mammals and amphibians.

Methods

Based on species range maps (spatial resolution: 20 km × 20 km) and an area-of-habitat approach, we calibrated a “species–energy model” by correlating the SR of three groups of vertebrates with net primary production and biogeographical covariables in “wilderness” areas (i.e., those where available energy is assumed to be still at pristine levels). We used this model to project the difference between pristine SR and the SR corresponding to the energy remaining in used landscapes (i.e., SR loss expected owing to human energy extraction outside wilderness areas). We validated the projected species loss by comparison with the realized and impending loss reconstructed from habitat conversion and documented by national Red Lists.

Results

Species–energy models largely explained landscape-scale variation of mapped SR in wilderness areas (adjusted R2-values: 0.79–0.93). Model-based projections of SR loss were lower, on average, than reconstructed and documented ones, but the spatial patterns were correlated significantly, with stronger correlation in mammals (Pearson's r = 0.68) than in amphibians (r = 0.60) and birds (r = 0.57).

Main conclusions

Our results suggest that the human appropriation of net primary production is a useful indicator of heterotrophic species loss in used landscapes, hence we recommend its inclusion in models based on species–area relationships to improve predictions of land-use-driven biodiversity loss.  相似文献   

3.

Aim

Whether intraspecific spatial patterns in body size are generalizable across species remains contentious, as well as the mechanisms underlying these patterns. Here we test several hypotheses explaining within-species body size variation in terrestrial vertebrates including the heat balance, seasonality, resource availability and water conservation hypotheses for ectotherms, and the heat conservation, heat dissipation, starvation resistance and resource availability hypotheses for endotherms.

Location

Global.

Time period

1970–2016.

Major taxa studied

Amphibians, reptiles, birds and mammals.

Methods

We collected 235,905 body size records for 2,229 species (amphibians = 36; reptiles = 81; birds = 1,545; mammals = 567) and performed a phylogenetic meta-analysis of intraspecific correlations between body size and environmental variables. We further tested whether correlations differ between migratory and non-migratory bird and mammal species, and between thermoregulating and thermoconforming ectotherms.

Results

For bird species, smaller intraspecific body size was associated with higher mean and maximum temperatures and lower resource seasonality. Size–environment relationships followed a similar pattern in resident and migratory birds, but the effect of resource availability on body size was slightly positive only for non-migratory birds. For mammals, we found that intraspecific body size was smaller with lower resource availability and seasonality, with this pattern being more evident in sedentary than migratory species. No clear size–environment relationships were found for reptiles and amphibians.

Main conclusions

Within-species body size variation across endotherms is explained by disparate underlying mechanisms for birds and mammals. Heat conservation (Bergmann's rule) and heat dissipation are the dominant processes explaining biogeographic intraspecific body size variation in birds, whereas in mammals, body size clines are mostly explained by the starvation resistance and resource availability hypotheses. Our findings contribute to a better understanding of the mechanisms behind species adaptations to the environment across their geographic distributions.  相似文献   

4.

Background

Telomeres are tandem repeats of TTAGGG at the end of eukaryotic chromosomes that play a key role in preventing chromosomal instability. The aim of the present study is to determine telomere length using fluorescence in situ hybridisation (FISH) on cytological specimens.

Methods

Aspiration samples (n = 41) were smeared on glass slides and used for FISH.

Results

Telomere signal intensity was significantly lower in positive cases (cases with malignancy, n = 25) as compared to negative cases (cases without malignancy, n = 16), and the same was observed for centromere intensity. The difference in DAPI intensity was not statistically significant. The ratio of telomere to centromere intensity did not show a significant difference between positive and negative cases. There was no statistical difference in the signal intensities of aspiration samples from ascites or pleural effusion (n = 23) and endoscopic ultrasound‐guided FNA samples from the pancreas (n = 18).

Conclusions

The present study revealed that telomere length can be used as an indicator to distinguish malignant and benign cells in cytological specimens. This novel approach may help improve diagnosis for cancer patients.  相似文献   

5.

Aims

Virus detection has often been difficult due to a low concentration in water. In this study, we developed a new procedure based on concentration of virus particles on an innovative support: poly‐l ‐lysine dendrigrafts (DGL), coupled with directed nucleic acid extraction and real‐time PCR quantification.

Methods and Results

This method was evaluated using the bacteriophage MS2 as a model virus. This virus exhibited the size and structural properties of human pathogenic enteric viruses and has often been used to assess new supports of concentration. Moreover, this bacteriophage is also a faecal contamination indicator. In this study, many water filtration conditions were tested (volume of water, concentration, etc.), and more than 80% of bacteriophage were recovered after filtration on polymer, in most conditions. We demonstrated that the method was linear (slope = 0·99 ± 0·04 and Y intercept when x = ?0·02 ± 0·28), valid (as manipulators, tested concentrations, volumes of sample and batch of polymer did not have any influence on concentration) and sensitive (allowing to concentrate up to 16 600‐fold 1 l of sample and to detect and quantify down to 750 GC l?1 and 7500 GC l?1, respectively).

Conclusions

To conclude, this support exhibits high interest to retain viruses and to allow to detect low concentration of virus in water.

Significance and Impact of the Study

This study gives valuable advance in the methods of concentration and diagnosis of virus in water.  相似文献   

6.

Background

Recent studies of Lactobacillus delbrueckii subsp. bulgaricus GLB44 plus a proton‐pump inhibitor (PPI) reported cures of more than 90% of patients with active Helicobacter pylori infections.

Aim

To confirm the high H. pylori cure rates reported previously.

Method

A pilot study was done in healthy H. pylori‐infected volunteers using 3‐gram sachet (3 billion cells) of L. delbrueckii GLB44 plus 22.3 mg of esomeprazole b.i.d., for 14 days. The result was determined by urea breath testing 4 weeks after therapy. Stopping rules required for ending enrollment if less than 3 of the first 10 subjects were cured.

Results

Nine subjects were entered and because all failed to achieve negative urea breath test, the stopping rule required the study to end.

Conclusion

We were unable to confirm reports of achieving a high H. pylori cure rate with L. delbrueckii GLB44 plus a PPI.  相似文献   

7.

Background

Helicobacter pylori is unevenly distributed in hypochlorhydric environments. The study aim was to elucidate the risk factors for a negative Giemsa staining finding in seropositive subjects by measuring the secretory ability of the stomach.

Methods

Subjects aged over 18 years were included consecutively after endoscopic biopsy at gastric lesions with color or structural changes. Blood was sampled for the serum pepsinogen (PG) assay and H. pylori serology test. After excluding the subjects with past H. pylori eradication, the risk factors for a negative Giemsa staining finding in seropositive subjects were analyzed.

Results

Among 872 included subjects, a discrepancy between the serum anti‐H. pylori IgG and Giemsa staining findings was found in 158 (18.1%) subjects, including 145 Giemsa‐negative, seropositive subjects. Gastric adenocarcinoma/adenoma (OR = 11.090, 95% CI = 3.490‐35.236) and low serum PG II level (OR = 0.931, 95% CI = 0.899‐0.963) were the independent risk factors for a negative Giemsa staining finding in seropositive subjects. The cutoff value of serum PG II level was 7.45 ng/mL (area under curve [AUC] = 0.904, 95% CI = 0.881‐0.927). Follow‐up studies of Giemsa staining at different sites of the stomach revealed that 75% of the Giemsa‐negative seropositive subjects with adenocarcinoma are positive, whereas none of those with low serum PG II level of <7.45 ng/mL revealed positive findings.

Conclusions

The risk of a negative Giemsa staining finding in seropositive subjects is increased in gastric adenocarcinoma/adenoma specimens and in subjects with a diminished gastric secretory ability with low serum PG II level of <7.45 ng/mL. A false‐negative Giemsa staining finding is common in subjects with adenocarcinoma, and therefore, additional biopsies at different sites should be performed in these subjects.  相似文献   

8.

Background  

The goal of our study is to examine the effect of stimulating a two-dimensional sheet of myocardial cells. We assume that the stimulating electrode is located in a bath perfusing the tissue.  相似文献   

9.
10.

Background

Helicobacter pylori eradication therapy is commonly performed to reduce the incidence of gastric cancer. However, gastric cancer is occasionally discovered even after successful eradication therapy. Therefore, we examined the prognosis of gastric cancer patients, diagnosed after successful H. pylori eradication therapy.

Materials and Methods

All‐cause death rates and gastric cancer‐specific death rates in gastric cancer patients who received successful H. pylori eradication treatment was tracked and compared to rates in patients who did not receive successful eradication therapy.

Results

In total, 160 gastric cancer patients were followed‐up for up to 11.7 years (mean 3.5 years). Among them, 53 gastric cancer patients received successful H. pylori eradication therapy prior to gastric cancer diagnosis. During the follow‐up period, 11 all‐cause deaths occurred. In the successful eradication group, the proportion of patients with cancer stage I was higher. The proportions of patients who received curative endoscopic therapy and endoscopic examination in the 2 years prior to gastric cancer diagnosis were also higher in the successful eradication group. Kaplan–Meier analysis of all‐cause death and gastric cancer‐specific death revealed a lower death rate in patients in the successful eradication group (P = .0139, and P = .0396, respectively, log‐rank test). The multivariate analysis showed that endoscopy within 2 years before cancer diagnosis is associated with stage I cancer.

Conclusions

Possible early discovery of gastric cancer after H. pylori eradication due to regular endoscopic surveillance may contribute to better prognosis of patients with gastric cancer.  相似文献   

11.

Background  

Carcinoma of the prostate metastasising to the penis is rare. These patients have a poor prognosis receiving various treatment modalities.  相似文献   

12.

Introduction

Tanshinones are a major class of bioactive ingredients in the traditional herbal medicines, Danshen (Salvia miltiorrhiza). A sensitive and reliable determination method for tanshinones is useful to ensure the quality of Danshen.

Objective

To develop a sensitive and selective analytical method for tanshinones by high‐performance liquid chromatography (HPLC) with fluorescence detection after pre‐column derivatisation.

Methodology

The proposed method depends on derivatisation reaction of tanshinones with 4‐carbomethoxybenzaldehyde and ammonium acetate forming intensely fluorescent imidazole derivative.

Results

The proposed method provided excellent sensitivity with the detection limits of 3.3 nM (66 fmol/injection), 3.2 nM (64 fmol/injection) and 2.0 nM (40 fmol/injection) for cryptotanshinone, tanshinone I and tanshinone IIA, respectively, without the necessity of complicated instrumentations. The developed method is successfully applied to quantify the contents of tanshinones in Danshen.

Conclusion

The developed method is the first analytical method for tanshinones by fluorescence detection. Since the derivatisation reaction is selective for the o‐quinone structure of tanshinone, the developed method will become a suitable mean for the discovering of tanshinone type diterpenoids from herbal samples. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   

13.
14.

Background  

Choriocarcinoma is an aggressive neoplasm arising in the body of the uterus. The disease normally spreads to lung and brain.  相似文献   

15.
16.

Background  

Neural induction is a complex process and the detailed mechanism of FGF-induced neurogenesis remains unclear.  相似文献   

17.

Aims

The objective was to determine the effect of the isoflavone biochanin A (BCA) on rumen cellulolytic bacteria and consequent fermentative activity.

Methods and Results

When bovine microbial rumen cell suspensions (n = 3) were incubated (24 h, 39°C) with ground hay, cellulolytic bacteria proliferated, short‐chain fatty acids were produced and pH declined. BCA (30 μg ml?1) had no effect on the number of cellulolytic bacteria or pH, but increased acetate, propionate and total SCFA production. Addition of BCA improved total digestibility when cell suspensions (n = 3) were incubated (48 h, 39°C) with ground hay, Avicel, or filter paper. Fibrobacter succinogenes S85, Ruminococcus flavefaciens 8 and Ruminococcus albus 8 were directly inhibited by BCA. Synergistic antimicrobial activity was observed with BCA and heat killed cultures of cellulolytic bacteria, but the effects were species dependent.

Conclusions

These results indicate that BCA improves fibre degradation by influencing cellulolytic bacteria competition and guild composition.

Significance and Impact of the Study

BCA could serve as a feed additive to improve cellulosis when cattle are consuming high‐fibre diets. Future research is needed to evaluate the effect of BCA on fibre degradation and utilization in vivo.  相似文献   

18.

Aim

In this study, the biological variation for improvement of the nutritive value of wheat straw by 12 Ceriporiopsis subvermispora, 10 Pleurotus eryngii and 10 Lentinula edodes strains was assessed. Screening of the best performing strains within each species was made based on the in vitro degradability of fungal‐treated wheat straw.

Methods and Results

Wheat straw was inoculated with each strain for 7 weeks of solid state fermentation. Weekly samples were evaluated for in vitro gas production (IVGP) in buffered rumen fluid for 72 h. Out of the 32 fungal strains studied, 17 strains showed a significantly higher (< 0·05) IVGP compared to the control after 7 weeks (227·7 ml g?1 OM). The three best Ceriporiopsis subvermispora strains showed a mean IVGP of 297·0 ml g?1 OM, while the three best P. eryngii and L. edodes strains showed a mean IVGP of 257·8 and 291·5 ml g?1 OM, respectively.

Conclusion

Ceriporiopsis subvermispora strains show an overall high potential to improve the ruminal degradability of wheat straw, followed by L. edodes and P. eryngii strains.

Significance and Impact of the Study

Large variation exists within and among different fungal species in the valorization of wheat straw, which offers opportunities to improve the fungal genotype by breeding.  相似文献   

19.

Background  

Totally implantable central venous access devices (intraports) are commonly used in cancer patients to administer chemotherapy or parenteral nutrition. Rupture of intraport is a rare complication.  相似文献   

20.

Background  

Multiple myeloma is a hematologic malignancy associated with the development of a destructive osteolytic bone disease.  相似文献   

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