Epidemiological studies suggest that tea may reduce cancer risk, and in
laboratory rodents, chemopreventive effects of tea or purified extracts of
tea have been demonstrated in lung, gastrointestinal tract and skin. There
is some evidence of chemoprevention by tea in the mammary gland, but the
data are not conclusive. In order to evaluate more fully the possible
influence of black tea on 7,12-dimethylbenz[a]anthracene (DMBA)-induced
mammary gland tumors in the female S-D (Sprague-Dawley) rat, three large
studies were performed: experiment 1, tumorigenesis in rats fed AIN-76A
diet and given 25 mg/kg DMBA and 1.25 or 2.5% whole tea extract or water to
drink; experiment 2, tumorigenesis in rats given 15 mg/kg DMBA and the same
diet and fluids as in experiment 1; experiment 3, tumorigenesis in rats fed
control or HF (high fat, corn oil) diet and given 15 mg/kg DMBA and 2% tea
or water to drink. Tea was given throughout the experiment; DMBA was given
by gastric gavage at 8 weeks of age. There was no consistent effect of tea
on tumorigenesis in rats fed AIN-76A diet; there was, however, evidence in
experiment 3 of a reduction of tumorigenesis by tea in rats fed the HF
diet. In experiment 3, rats fed the HF diet and given water showed the
expected increase in tumor burden (number and weight) compared with rats
fed control diet. However, rats fed the HF diet and given 2% tea showed no
increase in tumor burden; their tumor burden was significantly lower than
in rats fed the HF diet and given water (P < 0.01) and was not different
from rats fed control diet and given water or tea. In addition, in
experiment 3, the number of malignant tumors per tumor- bearing rat was
increased by the HF diet in water-drinking rats (P < 0.01) but not in
tea-drinking rats. Therefore, it appears that tea partially blocked the
promotion of DMBA-induced mammary tumorigenesis by the HF diet.
相似文献
The nucleocapsid (N) protein of SARS-coronavirus (SARS-CoV) is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membrane glycoprotein. In this study, the N protein of SARS-CoV was expressed in Escherichia coli DHSalpha and identified with pooled sera from patients in the convalescence phase of SARS. A plasmid pCI-N, encoding the full-length N gene of SARS-CoV, was constructed. Expression of the N protein was observed in COS1 cells following transfection with pCI-N. The immune responses induced by intramuscular immunization with pCI-N were evaluated in a murine model. Serum anti-N immunoglobutins and splenocytes proliferative responses against N protein were observed in immunized BALB/c mice. The major immunoglobulin G subclass recognizing N protein was immunoglobulin G2a, and stimulated splenocytes secreted high levels of gamma interferon and IL-2 in response to N protein. More importantly, the immunized mice produced strong delayed-type hypersensitivity (DTH) and CD^8+ CTL responses to N protein. 相似文献
Interruption of the contrast column during inspiration can lead to non‐diagnostic CT pulmonary angiograms. The importance of this artefact will increase with more CT studies being performed for pulmonary embolism on multidetector row CT. We describe here an instance of such an artefact and discuss its aetiology. 相似文献
We report a case of an assisted pregnancy in an asymptomatic woman who was found to have an extrauterine mass on ultrasound and MRI. This complex mass had equivocal imaging features and was found to be a ruptured ovarian ectopic pregnancy at surgery. This case illustrates that vigilance is required regarding the possibility of coexisting ectopic and intrauterine pregnancy following assisted conception, even in entirely asymptomatic cases. 相似文献
ObjectivesTo investigate differences between open and laparoscopic aortobifemoral bypass surgery for aorto-iliac occlusive disease on postoperative morbidity and mortality.DesignA multicentre randomised controlled trial.MethodsBetween January 2007 and November 2009, 28 patients with severe aorto-iliac occlusive disease (TASC II C or D) were randomised between laparoscopic and open approach at one community hospital and one university hospital (TASC = Trans-Atlantic Inter-Society Consensus on the Management of Peripheral Arterial Disease).ResultsThe operation time was longer for the laparoscopic approach (mean 4 h 19 min (2 h 00 min to 6 h 20 min) vs. 3 h 30 min (1 h 42 min to 5 h 11 min); p = 0.101)). Nevertheless, postoperative recovery and in-hospital stay were significantly shorter after laparoscopic surgery. Also oral intake could be restarted earlier (mean 20 h 34 min (6 h 00 min to 26 h 55 min) vs. 43 h 43 min (19 h 40 min to 77 h 30 min); p = 0.00014)) as well as postoperative mobilisation (walking) (mean 46 h 15 min (16 h 07 min to 112 h 40 min) vs. mean 94 h 14 min (66 h 10 min to 127 h 23 min); p = 0.00016)). Length of hospitalisation was shorter (mean 5.5 days (2.5–15) vs. mean 13.0 days (7–45); p = 0.0095)). Visual pain scores and visual discomfort scores were both lower after laparoscopic surgery. Also return to normal daily activities was achieved earlier. There were no major complications in both groups.ConclusionLaparoscopic aortobifemoral bypass surgery for aorto-iliac occlusive disease is a safe procedure with a significant decrease in postoperative morbidity and in-hospital stay and earlier recovery. 相似文献
Non-forensic or regular assertive community treatment (ACT) has positive effects on non-forensic outcomes but has poor effects on forensic outcome measures. In this study, we examined non-forensic and forensic outcome measures of a forensic adaptation of ACT (ForACT) within a continuum of care for internees. Data were collected retrospectively from files of 70 participants in the ForACT group who had been released from a forensic hospital. The control group comprised internees who had left prison and entered community-based care (n?=?56). The ForACT group demonstrated significantly better outcomes on forensic measures, such as arrests and incarcerations, and had better community tenure. However, this group showed high hospitalization rates. The findings indicate that this type of community-based care can be beneficial for such internees; however, internees continue to experience difficulties reintegrating into society. 相似文献
Working memory plays a role in various forms of psychopathology. However, working memory consists of multiple theoretical components that may be differently taxed by various specific types of task, and brain activation differences between patients and healthy controls may result from differences in task performance. This makes it difficult to interpret such results in terms of disease-related dysfunctions in affected regions or networks. The aim of the current study was to determine the brain activation related to the updating of spatiotemporal content of working memory, in such a way that performance-related confounds in future clinical studies would be minimized. Nineteen healthy volunteers performed a task involving a continuous updating process during fMRI measurement. A frontostriatal network including medial and lateral prefrontal cortex, inferior frontal cortex, premotor cortex, supplementary motor cortex, thalamus and putamen was found to be related to the updating process. The results constrain the set of brain regions plausibly related to the specific updating component of working memory. Further, the task design may be of use in future studies of pathological conditions such as schizophrenia due to the minimization of potential confounds. 相似文献
Summary
The prevalence of ESBL was determined among isolates of Escherichia coli (n = 571) and Klebsiella spp. (n = 196) collected during a 1-week study period in 8 university and 3 large regional laboratories all over the Netherlands.
18 isolates were positive for at least one of the screening tests used, i.e., VITEK-ESBL, E-test ESBL and MIC ratio of ceftazidime/ceftazidime-clavulanic
acid, cefotaxime/cefotaxime-clavulanic acid. In 5 of these 18 putative ESBLs no betalactamase production was detectable. A
TEM type was found in three E. coli and two Klebsiella spp. An SHV type was present in five Klebsiella spp. In one E. coli and one Klebsiella pneumoniae both enzymes were present. In one Klebsiella oxytoca neither of the two enzymes was present. Using PCR for both ESBL TEM and ESBL SHV, an SHV ESBL was found in one E. coli and four Klebsiella isolates. The mutations at position 238 and 240 were already described. In one E. coli isolate a TEM ESBL was found with three mutations, at position 21, 164 and 265. These mutations were already described in
other ESBLs but not in this combination suggesting a new TEM ESBL. The overall prevalence of ESBL producing E. coli and Klebsiella spp. was less than 1% (6 out of 767).
Received: December 14, 1998 · Accepted: September 19, 1999 相似文献
Paroxysmal kinesigenic dyskinesia is an episodic movement disorder caused by dominant mutations in the proline-rich transmembrane protein PRRT2, with onset in childhood and typically with improvement or resolution by middle age. Mutations in the same gene may also cause benign infantile seizures, which begin in the first year of life and typically remit by the age of 2 years. Many details of PRRT2 function at the synapse, and the effects of mutations on neuronal excitability in the pathophysiology of epilepsy and dyskinesia, have emerged through the work of several groups over the last decade. However, the age dependence of the phenotypes has not been explored in detail in transgenic models. Here, we report our findings in heterozygous and homozygous Prrt2 knockout mice that recapitulate the age dependence of dyskinesia seen in the human disease. We show that Prrt2 deletion reduces the levels of synaptic proteins in a dose-dependent manner that is most pronounced at postnatal day 5 (P5), attenuates at P60, and disappears by P180. In a test for foot slippage while crossing a balance beam, transient loss of coordination was most pronounced at P60 and less prominent at age extremes. Slower traverse time was noted in homozygous knockout mice only, consistent with the ataxia seen in rare individuals with biallelic loss of function mutations in Prrt2. We thus identify three age-dependent phenotypic windows in the mouse model, which recapitulate the pattern seen in humans with PRRT2-related diseases.