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41.
A. V. Bennett D. L. Patrick D. M. Bushnell C. F. Chiou P. Diehr 《Quality of life research》2011,20(5):769-777
Purpose
Patient reporting of type 2 diabetes symptoms in a questionnaire with a 7-day recall period was expected to be different from symptom reports using a 7-day diary with repeated 24-h recall based on cognitive theory of memory processes and prior literature. This study compared these two types of recall in patients diagnosed with type 2 diabetes (T2D). 相似文献42.
BD Heckman KA Holroyd G Tietjen FJ O'Donnell L Himawan C Utley R Watakakosol & M Stillman 《Cephalalgia : an international journal of headache》2009,29(6):650-661
This study sought to determine if Whites and African-Americans respond similarly to headache treatment administered in 'real-world' headache specialty treatment clinics. Using a naturalistic, longitudinal design, 284 patients receiving treatment for headache disorders completed 30-day daily diaries that assessed headache frequency and severity at pretreatment and 6-month follow-up and also provided data on their headache disability and quality of life at pretreatment and 1-, 2- and 6-month follow-up. Controlling for socioeconomic status and psychiatric comorbidity, hierarchical linear models found that African-Americans and Whites reported significant reductions in headache frequency and disability and improvements in life quality over the 6-month treatment period. African-Americans, unlike Whites, also reported significant decreases in headache severity. Nevertheless, Africans-Americans had significantly more frequent and disabling headaches and lower quality of life after treatment relative to Whites. Although Whites and African Americans responded favourably to headache treatments, more efficacious treatments are needed given the elevated level of headache frequency that remained in both racial groups following treatment. 相似文献
43.
44.
Gloria Peiró MD Encarna Adrover MD Jaime Guijarro MD Irene Ballester MD M. José Jimenez MD María Planelles MD Lluis Catasús BD 《The breast journal》2010,16(1):77-81
Abstract: Synchronous bilateral breast carcinoma (SBBC) and early onset are important characteristics of hereditary cases. The lifetime risk for breast carcinoma in Cowden syndrome (CS) is estimated to be 25–50%. We reported a 44‐year‐old woman presenting SBBC and characteristic mucocutaneous lesions of CS, confirmed by PTEN gene mutation analysis. Bilateral modified mastectomy and axillary dissection were performed. Histopathologic examination revealed a moderate‐differentiated invasive ductal carcinoma with mixed features of luminal A immunophenotype (Estrogen and/or Progesterone Receptors >50% and/or Ki67 < 30% of positive cells). The skin lesions showed the characteristic findings of tricholemmoma. Lack of PTEN expression was observed in all specimens. Sequencing analysis confirmed the presence of PTEN splice‐acceptor site mutation in intron 8 (c.1027‐2A>G), a germline mutation which had not been previously reported in CS. The patient received adjuvant chemotherapy and tamoxifen for 5 years. After 5 years of follow‐up, she persists recurrence‐free. SBBC with early onset suggests a hereditary predisposition. Thus, analysis of PTEN expression abnormality, easily assessed by immunohistochemistry, may be of clinical value to screen those patients with CS. 相似文献
45.
46.
Behavior of osteoblast,adipocyte, and myoblast markers in genome-wide expression analysis of mouse calvaria primary osteoblasts in vitro 总被引:3,自引:0,他引:3
47.
De Flora S; Camoirano A; Bagnasco M; Bennicelli C; Corbett GE; Kerger BD 《Carcinogenesis》1997,18(3):531-537
Estimates of the overall reducing capacity of hexavalent chromium(VI) in
some human body compartments were made by relating the specific reducing
activity of body fluids, cell populations or organs to their average
volume, number, or weight. Although these data do not have absolute
precision or universal applicability, they provide a rationale for
predicting and interpreting the health effects of chromium(VI). The
available evidence strongly indicates that chromium(VI) reduction in body
fluids and long-lived non-target cells is expected to greatly attenuate its
potential toxicity and genotoxicity, to imprint a threshold character to
the carcinogenesis process, and to restrict the possible targets of its
activity. For example, the chromium(VI) sequestering capacity of whole
blood (187-234 mg per individual) and the reducing capacity of red blood
cells (at least 93-128 mg) explain why this metal is not a systemic
toxicant, except at very high doses, and also explain its lack of
carcinogenicity at a distance from the portal of entry into the organism.
Reduction by fluids in the digestive tract, e.g. by saliva (0.7-2.1 mg/day)
and gastric juice (at least 84- 88 mg/day), and sequestration by intestinal
bacteria (11-24 mg eliminated daily with feces) account for the poor
intestinal absorption of chromium(VI). The chromium(VI) escaping reduction
in the digestive tract will be detoxified in the blood of the portal vein
system and then in the liver, having an overall reducing capacity of 3300
mg. These processes give reasons for the poor oral toxicity of chromium(VI)
and its lack of carcinogenicity when introduced by the oral route or
swallowed following reflux from the respiratory tract. In terminal airways
chromium(VI) is reduced in the epithelial lining fluid (0.9-1.8 mg) and in
pulmonary alveolar macrophages (136 mg). The peripheral lung parenchyma has
an overall reducing capacity of 260 mg chromium(VI), with a slightly higher
specific activity as compared to the bronchial tree. Therefore, even in the
respiratory tract, which is the only consistent target of chromium(VI)
carcinogenicity in humans (lung and sinonasal cavities), there are barriers
hampering its carcinogenicity. These hurdles could be only overwhelmed
under conditions of massive exposure by inhalation, as it occurred in
certain work environments prior to the implementation of suitable
industrial hygiene measures.
相似文献
48.
Visual thresholds for luminance increments were obtained behaviorally and electrophysiologically from rats exposed to a polychlorinated biphenyl (PCB) during development. Male Long-Evans rats exposed to 0, 0.25, or 1.0 microg/kg/day of 3,3',4,4', 5-pentachlorobiphenyl (PCB 126) through gestation and weaning were trained as adults to perform a signal detection task. Estimates of threshold were derived from psychometric functions for each animal relating the proportion of hits to signal intensity. Thresholds derived under three luminance conditions did not differ significantly among the PCB-treated groups. After behavioral testing was completed, flash-evoked potentials were recorded from dark-adapted awake animals. Peak amplitudes increased linearly over approximately 3 log units of intensity. Extrapolations to 0 amplitude along the linear portion of the amplitude-log intensity functions produced estimates of absolute threshold of -5.44 to -5.53 log cd/m(2)-s. Waveforms recorded from awake animals had a large late negative component that was absent in previously reported anesthetized preparations. Developmental exposure to PCB 126 had no significant effect on absolute threshold or peak amplitudes and latencies. 相似文献
49.
50.
Effect of proton pump inhibitors on the detection of Helicobacter pylori in gastric biopsies. 总被引:4,自引:0,他引:4
BACKGROUND: Proton pump inhibitors are known to decrease the activity of Helicobacter pylori organisms within the stomach and to shift their distribution proximally. This effect may reduce the sensitivity of histological examination and rapid urease testing for H. pylori on biopsies taken from recommended sites. It is of particular relevance if a proton pump inhibitor has been prescribed before the patient has undergone diagnostic endoscopy. METHODS: We studied patients referred to our open-access upper gastrointestinal endoscopy service who had either been on no medication (controls) or were already taking proton pump inhibitors. Biopsies taken from the gastric antrum and corpus were used for rapid urease testing and for histological examination. Sera, taken from patients who had no evidence of H. pylori in biopsies, were tested for IgG H. pylori antibodies as an alternative indicator of infection. RESULTS: H. pylori organisms were detected by histological examination in 27 of 40 controls (68%) and in 13 of 25 patients taking proton pump inhibitors (52%). Among patients with positive histology (organisms detected in either antral or corpus biopsies, or both), only the sensitivity of the antral urease test read at 1 h was significantly lower in patients taking proton pump inhibitors than in controls, with no significant difference in sensitivities of the antral urease test at 24 h, of the corpus urease test at 1 or 24 h, or of histology from the antrum or corpus. Of patients with negative histology, none of 13 controls compared with six of 12 patients taking proton pump inhibitors (50%) had positive serology (P = 0.005). Five (83%) of the six histology-negative, seropositive patients taking proton pump inhibitors had histological changes consistent with H. pylori gastritis even though no organisms were detected. CONCLUSIONS: Treatment with a proton pump inhibitor before endoscopy reduces the sensitivity of antral and corpus biopsies for H. pylori detection, both by urease testing and histological examination. If proton pump inhibitors already prescribed cannot be discontinued for an adequate period before endoscopy, patients should have biopsies taken from the corpus as well as from the antrum, and serum should be tested for H. pylori. 相似文献