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101.
The establishment of rat embryonic stem cells constitutes a precious tool since rat has been extensively used in biomedical research, in particular for the generation of human neurodisease animal models. Up to now only a few studies have described the isolation of rat embryonic stem-like cells. One out of 9 isolated rat embryonic stem-like cell lines (B1-RESC) obtained from a 4.5-day post-coitum blastocyst were extensively characterized and kept in culture for up to 80 passages on feeders with LIF. The stable growth of these cells and the expression of pluripotent markers were confirmed up to a high number of passages in culture, also in the absence of feeders and LIF. B1-RESC expresses the three germ layers markers both in vitro, within differentiating embryoid bodies, and in vivo through teratoma formation. Collectively, the B1-RESC line with a stable near-diploid karyotype can be used as a highly sensitive tool for testing anti-proliferative molecules.  相似文献   
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103.
Several studies have focused on the relationship between metabolic syndrome and gastroesophageal reflux disease (GERD). They were based on GERD complications, whereas little is known about the association between metabolic syndrome and objectively measured esophageal acid exposure. The aim of our study was to assess the relationship between metabolic syndrome and GERD based on a 24‐hour pH testing. It was a cross‐sectional study including 100 consecutive patients who underwent a 24‐hour pH‐metry monitoring and were assessed for the five metabolic syndrome components as well as for body mass index (BMI). Among the 100 patients, 54 had a pathological acid GERD. The 46 GERD‐free patients represented control group. Sex distribution was comparable between both groups but GERD patients were older than controls (44.59 vs. 37.63 years, P= 0.006) and more often obese or with overweight (83.3 vs. 60.9%, P= 0.01). Frequency of metabolic syndrome as a whole entity was higher among patients with GERD than those without GERD (50 vs. 19.56%; P= 0.002) with a crude odds ratio of 4.11 (95% confidence interval: 1.66–10.14). Multivariate regression analysis showed that metabolic syndrome as well as an age ≥30 years were independent factors associated to GERD but not BMI and sex. Abnormal waist circumference and fasting glucose level ≥100 mg/L were the only independent factors among the five components of metabolic syndrome. Metabolic syndrome but not BMI was an independent factor associated to GERD. These results confirm the hypothesis that central obesity is associated to GERD.  相似文献   
104.
105.
Secondary cervical adenocarcinomas are most commonly seen owing to the extension of a primary endometrial adenocarcinoma. Metastatic tumors from other sites are rather uncommon and, when seen, are most frequently from the ovaries, gastrointestinal tract, or breast. We report a case of metastatic renal cell carcinoma, clear cell variant, to the cervix, which presented as a cervical polyp in a postmenopausal female. To our knowledge, this is the fourth reported case of renal cell carcinoma metastatic to the cervix. This case is only the third in which the cervical metastasis was the presenting sign of renal cell carcinoma and the first in which the clinical presentation was as a cervical polyp.  相似文献   
106.
The paper is an up to date overview of knowledge on iron metabolism that integrate recent findings in this field. Significant advances were made in understanding the implication of protein factors (transporters, enzymes and regulation factors) in iron metabolism, as well as related genetic abnormalities. The research highlighted the complexity of mechanisms in charge of maintaining equilibrium of Fe in the body. The iron is vital to the life of cells, but its presence in excess is rather toxic. Iron is mostly required for hemoglobin synthesis. It is recycled between reticulo-endothelial macrophages and bone marrow that is the main user of iron. Intestinal absorption is a key step in determining iron capital in the body. Its rate is tightly controlled by several factors that act under influence of signals of unknown nature, which indicate iron needs and storage. The IRP/IRE (iron regulatory protein/iron responsive element) system controls cellular uptake, stores and exportation of iron, and heme synthesis. Mitochondrion is a dynamo of iron metabolism, being vital for heme synthesis and iron sulphur cluster genesis. The recent discovery of several mitochondrial proteins involved in iron metabolism resulted in better understanding mitochondrial iron movement, storage and exchange. Nevertheless, much remains to be known on the role of some actors such as HFE protein, hepcidin, hemojuvelin and transferrin receptor 2, and to determine the nature and mechanisms of signals regulating iron level in the body.  相似文献   
107.
BACKGROUND: Schistosomal infections of the female reproductive tract are common in countries where the parasite is endemic. Serious complications, such as ectopic pregnancy and infertility, may arise in patients with gynecologic schistosomiasis. CASE: A primiparous, African woman presented with vaginal bleeding and was found to have an ectopic pregnancy. Laparoscopy revealed distorted pelvic anatomy due to dense adhesions. Pathologic examination confirmed an ectopic pregnancy and identified Schistosoma haematobium ova in the patient's fallopian tube. Urine examination was confirmatory, and the patient was treated and referred for fertility counseling. CONCLUSION: Clinicians should consider schistosomiasis as a possible etiology for gynecologic complaints, including serious complications such as ectopic pregnancy and infertility, in patients from endemic regions.  相似文献   
108.
The presence of a fifth mandibular incisor, a eumorphic supernumerary tooth, has rarely been described in the literature. Recently we reported on a large Lebanese consanguineous family where 4 individuals displayed 5 mandibular incisors with the same shape and size. This type of familial clustering of the trait has not been previously described. We previously postulated several theories to explain the etiology of this anomaly. The possibility of an autosomal recessive inheritance for this nonsyndromic trait was discussed. We now report the use of homozygosity mapping to identify a homozygous region with different alleles at chromosome 16q12.2, located at the marker D16S415, which likely harbors the gene underlying this anomaly.  相似文献   
109.

Background

It has been shown that neutrophil count or an elevated neutrophil-to-lymphocyte ratio (NLR) as well as testosterone levels are separately associated with increased mortality in patients with localized prostate cancer.

Objective

We tested a combination of testosterone levels and white blood cell (WBC) counts to predict overall survival (OS) in a prospective cohort of patients treated with radiotherapy for localized prostate cancer.

Patients and Methods

The 381 patients included in this study were prospectively enrolled in phase 2 or 3 studies. Multivariate Cox proportional hazards models were used to analyze the influence of WBC count and testosterone level on biochemical recurrence and OS. Cutoff levels of ≤10.4 nmol/L (300 ng/dL) for testosterone and a median value of 6.2 (×109/L) for WBC count were used.

Results

The median follow-up for biochemical recurrence and OS were 72 and 78 months, respectively. A WBC count of ≥6.2 alone was not associated with OS (hazard ratio [HR] 0.66; 95% confidence interval [CI] 0.30–1.46). When combined with a testosterone level of >10.3 nmol/L, a WBC count of ≥6.2 was associated with increased mortality (HR 2.96; 95% CI 1.45–6.06) when compared with a WBC count of <6.2 (p-interaction = 0.01). The HR for biochemical recurrence for patients with a testosterone level >10.3 nmol/L combined with a lymphocyte level above or equal to the median was nearly identical to the HR of a testosterone level >10.3 nmol/L with a WBC above or equal to the median. There was no association between testosterone level and the NLR.

Conclusions

A high WBC and lymphocyte count combined with normal testosterone levels increases the overall mortality of patients treated with radiotherapy for localized prostate cancer within the first 6–7 years post-treatment. Validation in larger cohorts is necessary.
  相似文献   
110.
Salt stress tolerance of durum wheat was assessed in control and 200 and 300 mM NaCl-exposed seed of two cultivars (BidiAP4 and Azizi). These salt treatments were accompanied by different levels of nitrate (Ca(NO3)2) added to the media (0.1, 3, 10 mM). The data showed that NaCl stress increased Na+ and Cl? contents and lowered K+ and NO3 ? levels in seeds of BidiAP4 cultivar. In Azizi seeds exposed to NaCl, Na+ and K+ were highly accumulated while low levels of NO3 ? and Cl? were detected. Those findings highlight the difference in the salt stress tolerance of these two durum wheat cultivars also depending on nitrogen (N) availability, Azizi cultivar being less sensitive to NaCl treatment than BidiAP4. These data also suggested a relationship between salt tolerance capacity and enhancement or maintenance of nitrogen and carbon metabolisms enzyme activity.  相似文献   
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