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排序方式: 共有560条查询结果,搜索用时 15 毫秒
91.
92.
Melia KARAK
SE Muhammet KOCABA Mustafa CAN Hatice ALIKAN BURGUCU lker ORDAN Mustafa KULAKSIZOLU Feridun KARAKURT 《Turkish Journal of Medical Sciences》2021,51(4):2023
Background/aimPrimary hyperparathyroidism (PHPT) is a disease that is diagnosed more frequently and generally in the asymptomatic period, with widely available biochemical tests. Evidence suggesting an association between PHPT and malignancy risk is increasing. Clarification of this association will be useful in PHPT for malignancy screening and management of patients with PHPT. In this study, we aimed to investigate the frequency of cancer in PHPT patients.Materials and methodsA total of 775 PHPT patients were included in the retrospective study. Demographic, clinical and laboratory data of the patients were evaluated retrospectively.ResultsMalignancy was detected in 128 (16.50%) of 775 PHPT patients (female/male: 625/150). The mean age at diagnosis of PHPT was 57.99 ± 10.86 years, and the mean age at diagnosis of malignancy was 57.46 ± 11.17 years. Of the 128 patients with malignancy, 53 (41.40%) were diagnosed in the same year as PHPT. In terms of malignancy types, 51 (6.50%) of 775 PHPT patients had thyroid cancer. Thyroid cancer was followed by breast cancer (2.30%) and stomach cancer (1%) in order of frequency.ConclusionWe think that PHPT patients should be examined more carefully in terms of cancer risk, especially thyroid cancer. More comprehensive studies are needed to clarify the relationship between PHPT and cancer. 相似文献
93.
94.
Stephen D. Ginsberg Peter B. Crino Scott E. Hemby Jeremy A. Weingarten Virginia M.-Y. Lee James H. Eberwine John Q. Trojanowski 《Annals of neurology》1999,45(2):174-181
The sequestration of RNA in Alzheimer's disease (AD) senile plaques (SPs) and the production of intraneuronal amyloid-β peptides (Aβ) prompted analysis of the mRNA profile in single immunocytochemically identified SPs in sections of AD hippocampus. By using amplified RNA expression profiling, polymerase chain reaction, and in situ hybridization, we assessed the presence and abundance of 51 mRNAs that encode proteins implicated in the pathogenesis of AD. The mRNAs in SPs were compared with those in individual CA1 neurons and the surrounding neuropil of control subjects. The remarkable demonstration here, that neuronal mRNAs predominate in SPs, implies that these mRNAs are nonproteinaceous components of SPs, and, moreover, that mRNAs may interact with Aβ protein and that SPs form at sites where neurons degenerate in the AD brain. Ann Neurol 1999;45:174–181 相似文献
95.
96.
Predicting serious bacterial infection in young children with fever without apparent source 总被引:1,自引:0,他引:1
SE Bleeker KGM Moons G Derksen-Lubsen DE Grobbee HA Moll 《Acta paediatrica (Oslo, Norway : 1992)》2001,90(11):1226-1231
The aim of this study was to design a clinical rule to predict the presence of a serious bacterial infection in children with fever without apparent source. Information was collected from the records of children aged 1-36 mo who attended the paediatric emergency department because of fever without source (temperature > or = 38 degrees C and no apparent source found after evaluation by a general practitioner or history by a paediatrician). Serious bacterial infection included bacterial meningitis, sepsis, bacteraemia, pneumonia, urinary tract infection, bacterial gastroenteritis, osteomyelitis and ethmoiditis. Using multivariate logistic regression and the area under the receiver operating characteristic curve (ROC area), the diagnostic value of predictors for serious bacterial infection was judged, resulting in a risk stratification. Twenty-five percent of the 231 patients enrolled in the study (mean age 1.1 y) had a serious bacterial infection. Independent predictors from history and examination included duration of fever, poor micturition, vomiting, age, temperature < 36.7 degrees C or > or = 40 degrees C at examination, chest-wall retractions and poor peripheral circulation (ROC area: 0.75). Independent predictors from laboratory tests were white blood cell count, serum C-reactive protein and the presence of >70 white blood cells in urinalysis (ROC area: 0.83). The risk stratification for serious bacterial infection ranged from 6% to 92%. CONCLUSION: The probability of a serious bacterial infection in the individual patient with fever without source can be estimated more precisely by using a limited number of symptoms, signs and laboratory tests. 相似文献
97.
JACQUELINE CHAUVET WON-JAE LEE MARIE-THRSE CHAUVET ROGER ACHER 《Chemical biology & drug design》1994,44(2):130-138
The two types of neurophysins known in vertebrate species, namely MSEL-neurophysin (vasopressin-like hormone-associated neurophysin) and VLDV-neurophysin (oxytocin-like hormone-associated neurophysin) have been purified from the pollack (Pollachius virens) pituitary through a combination of molecular sieving and high-pressure liquid chromatography (HPLC). Homogeneity has been checked by gel electrophoresis and rerun in HPLC. The apparent molecular masses measured by SDS-electrophoresis are near 12 kDa, significantly higher than those found for their mammalian homologues (10 kDa). The two types of neurophysins have been recognized through their N-terminal amino acid sequences. The primary structure of MSEL-neurophysin has been partially determined using automated Edman degradation applied on native and reduced-alkylated protein, as well as peptides derived by trypsin or staphylococcal proteinase hydrolyses. Comparison of pollack MSEL-neurophysin with ox, goose and frog counterparts reveals that particular positions in the polypeptide chain are subjected to substitutions and that the numbers of substitutions do not seem closely related to the paleontological times of divergence between the different vertebrate classes. 相似文献
98.
Background and purpose:
Angiotensin II receptor antagonists (ARBs), originally developed for antihypertensive properties, have pleiotropic effects including direct vascular actions. We tested the hypothesis that the ARB irbesartan would be effective against micro- and macrovascular complications of the prediabetic metabolic syndrome using the obese, insulin-resistant JCR : LA-cp rat that exhibits micro- and macrovascular disease with ischaemic myocardial lesions and renal disease.Experimental approach:
Obese male rats were treated with irbesartan (30 mg·kg−1·day−1, incorporated into chow) from 12 to 25 weeks of age.Key results:
Irbesartan treatment caused no change in food intake or body weight. Fasting glycaemic control of the JCR : LA-cp rats was marginally improved, at the expense of increased plasma insulin levels (∼50%). Fasting plasma triglycerides were marginally reduced (∼25%), while cholesterol concentrations were unchanged. Elevated concentrations of adiponectin, monocyte chemotactic protein-1 and plasminogen activator inhibitor-1 were reduced along with severity of glomerular sclerosis. Macrovascular dysfunction (aortic hypercontractile response to noradrenergic stimulus and reduced endothelium-dependent relaxation) was improved and frequency of ischaemic myocardial lesions reduced (62%).Conclusions and implications:
Irbesartan reduces markers of inflammation and prothombotic status, improves macrovascular function and reduces glomerular sclerosis and myocardial lesions in a model of the metabolic syndrome. Unlike pharmaceutical agents targeted on metabolic dysfunction, irbesartan reduced end-stage disease without major reduction of plasma lipids or insulin. The protective effects appear to be secondary to unknown intracellular mechanisms, probably involving signal transduction pathways. Understanding these would offer novel pharmaceutical approaches to protection against cardiovascular disease. 相似文献99.
A prospective study of methylenetetrahydrofolate reductase and methionine synthase gene polymorphisms, and risk of colorectal adenoma 总被引:8,自引:2,他引:8
Chen J; Giovannucci E; Hankinson SE; Ma J; Willett WC; Spiegelman D; Kelsey KT; Hunter DJ 《Carcinogenesis》1998,19(12):2129-2132
We examined the relationship between a functional polymorphism (667C--
>T, ala-->val) of the methylenetetrahydrofolate reductase gene
(MTHFR) and the risk of colorectal adenomas in the prospective Nurses'
Health Study. Among 257 incident polyp cases and 713 controls, the MTHFR
val/val polymorphism [relative risk (RR) = 1.35, 95% confidence interval
(CI) 0.84-2.17] was not significantly associated with risk of adenomas.
This lack of association was observed for both small (RR = 1.36, 95% CI
0.76-2.45) and large (RR = 1.32, 95% CI 0.66-2.66) adenomas. Furthermore,
there was no significant interaction between this polymorphism and
consumption of either folate, methionine or alcohol. We also examined the
relationship of a newly identified polymorphism (asp919gly) of the
methionine synthase gene (MS) with the risk of colorectal adenomas in the
same population. The MS gly/gly polymorphism was also not significantly
associated with risk of colorectal adenomas (RR = 0.66, 95% CI 0.26-1.70).
These results, which need to be confirmed in other studies, suggest that
the MTHFR val/val polymorphism, which has been previously inversely
associated with risk of colorectal cancer, plays a role only in a late
stage (adenoma-- >carcinoma) of colorectal tumorigenesis, and/or may
protect against malignant transformation in the subset of benign adenomas,
which may progress to malignancy.
相似文献
100.