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31.
The importance of hunger state for the acquisition and expression of chocolate craving was investigated. Seventeen chocolate cravers and 12 non-cravers were supplied with chocolate and instructed to eat some twice a day for 14 days. Within each group, subjects were allocated to one of two conditions, hungry- or full-trained. Hungry-trained subjects were asked to eat the chocolate exclusively at least 2 h after last eating; full-trained subjects were asked only to eat the chocolate 15-30 min after eating a meal. A diary was kept to encourage and allow assessment of compliance. At the start and end of the 2 weeks, subjects rated their craving for and anticipated intake of chocolate prior to eating it; then, on initial tasting, pleasantness of the taste was rated. All subjects made these ratings on one day when hungry and on another when full, as defined above. For cravers and non-cravers who ate chocolate exclusively when hungry, chocolate craving increased post-training, but, at least for cravers, only when ratings were made while hungry. For full-trained subjects, chocolate craving decreased post-training, but this decrease did not depend on whether subjects were currently hungry or full. A similar pattern of results was found for anticipated intake and pleasantness of taste, except that pleasantness did not increase in hungry-trained subjects. The results are interpreted with reference to learned control of appetite and in particular to recent findings on incentive learning processes. Craving for chocolate or other foods may be an expression of a strong appetite elicited by hunger that has been acquired by repeated experience of eating the craved food when hungry. 相似文献
32.
Matrix Metalloproteinase Inhibitors: Applications in Oncology 总被引:9,自引:0,他引:9
Matrix metalloproteinases (MMP) are a group of zinc dependentenzymes which include the interstitial collagenases, stromelysins,gelatinases and membrane-type metalloproteinases. They are involvedin the remodelling and turnover of the extracellular matrixproteins. They play a role in wound healing and the pathogenesis ofarthritis. In malignancies they play a role in tumor invasion,metastasis and angiogenesis. A number of synthetic matrixmetalloproteinase inhibitors (MMPIs) have been developed forclinical use. In preclinical tumor models they have shown promisingactivity in achievinginhibition of MMPs and reducing tumor growth and metastatic spread.Some have also shown additive or synergistic effects with cytotoxicagents. Phase I and II studies in human subjects have defined themain side effects of these agents as beingmusculoskeletal pains or arthralgias. As they are cytostatic agentsrather than cytotoxic in activity conventional measurements ofradiological response for assessment are not applicable in trials.Biological activity has been demonstrated in certain cancers by theeffects on levels of tumor markers as surrogate markers of tumorresponse and also by a fibrotic stromal reaction seen in tumortissue. Newer agents have been developed withselective inhibition of certain MMPs in an attempt to reduce theside effects. A number of phase III human clinical trialsevaluating MMPs are being carried out at present but onlyone has been formally reported so far. This study suggested thatmarimastat had no survival advantage when compared to chemotherapywith gemcitabine in advanced pancreatic carcinoma. Current trialsare assessing efficacy of MMPIs in maintenance of remission afterother modalities of therapy or in combination with cytotoxicagents. MMPs have also been demonstrated to play an important rolein the articular cartilage destruction seen in both rheumatoidarthritis and osteoarthritis. The use of MMPIs in both exvivoand in vivomodels have shown promising resultsand trials are in process to assess their potential role in thecontrol of articular destruction. The true therapeutic role ofMMPIs await the results of these randomized studies. 相似文献
33.
Mexican-American heroin addicts 总被引:1,自引:0,他引:1
Next to Blacks, Mexican-Americans are the largest ethnic minority group among the visible opioid addict population in the United States. Although commonly grouped together with Puerto Ricans and other Spanish-speaking peoples under the rubric "Hispanic," Mexican-Americans have a unique culture and ethnohistory. In this report we review the clinical and research literature and present new data from studies of Mexican-American opioid users in San Antonio. Mexican-American addicts tend to use fewer classes of illicit drugs and are less likely to use stimulants and psychedelics than Whites or Blacks. Onset of daily opioid use occurs at an early age, typically around 20, yet first voluntary admission to treatment usually occurs later than it does for other ethnic groups. Mexican-American addicts tend to be arrested more frequently and spend significantly more years in correctional institutions, but there is also evidence that they spend more time voluntarily abstinent and employed during their careers. The duration of the career is prolonged, however, and typically exceeds 20 years. Mexican-Americans prefer individual to group treatment, and are especially unlikely to participate in traditional therapeutic communities and group psychotherapies. The Mexican-American client is the least likely to complete treatment without adverse termination. The literature seems unanimous in calling for more treatment of Mexican-American addicts by Mexican-American therapists, but we found little empirical outcome data which demonstrated that ethnic matching of therapist and client brings better results. 相似文献
34.
Sullivan EV Deshmukh A Desmond JE Mathalon DH Rosenbloom MJ Lim KO Pfefferbaum A 《Archives of general psychiatry》2000,57(9):894-902
BACKGROUND: It is controversial whether cerebellar tissue volume deficits occur in schizophrenia and, if so, what regions and tissue types are affected. Complicating such investigations is the high incidence of alcoholism comorbidity in patients with schizophrenia that itself can contribute to cerebellar abnormalities. METHOD: We studied 61 healthy men (control subjects), 25 men with alcoholism, 27 men with schizophrenia, and 19 men comorbid for schizophrenia and alcoholism with the use of magnetic resonance imaging. Cerebellar structures were outlined manually, tissue classification was determined statistically, and regional volumes were corrected for normal variation in head size and age. RESULTS: Patients with schizophrenia alone had enlarged fourth ventricles (1.5 SD relative to controls) but showed no cerebellar tissue volume deficits. The alcoholic group had gray and white matter vermian deficits (-0.5 SD), most prominent in anterior superior lobules, and gray matter hemisphere deficits (-0.8 SD), but not fourth ventricle enlargement. The comorbid group had cerebellar hemisphere (-1.3 SD) and vermian gray matter volume deficits (-0.7 SD) and fourth ventricular enlargement (1.6 SD); these abnormalities were greater than in either single-diagnosis group, despite significantly lower levels of alcohol consumption compared with the alcoholic group. Gray matter volume in the anterior superior vermis correlated with lifetime alcohol consumption in the schizophrenic and comorbid groups when combined. CONCLUSIONS: Cerebellar tissue volume deficits were detected in schizophrenia only when accompanied by alcoholism. By contrast, fourth ventricular enlargement occurred in schizophrenia even without alcoholism, although it was exacerbated by alcoholism. These findings support a model of cerebellar supersensitivity to alcohol-related tissue volume deficits in schizophrenia. 相似文献
35.
Viviane Hess Roger A'Hern Nazar Nasiri D Michael King Peter R Blake Desmond P J Barton John H Shepherd T Ind J Bridges K Harrington Stanley B Kaye Martin E Gore 《Journal of clinical oncology》2004,22(6):1040-1044
PURPOSE: Invasive mucinous carcinoma of the ovary (mucinous epithelial ovarian cancer [mEOC]) is a histologic subgroup of epithelial ovarian cancer (EOC). Chemotherapy for mEOC is chosen according to guidelines established for EOC. The purpose of this study is to determine whether this is appropriate. PATIENTS AND METHODS: Women with advanced mEOC (International Federation of Gynecology and Obstetrics stage III or IV) who underwent first-line platinum-based chemotherapy were compared with women with other histologic subtypes of EOC in a case-controlled study. RESULTS: Eighty-one patients (27 cases, 54 controls) treated with platinum-based regimens were analyzed. The response rates for cases and controls were 26.3% (95% CI, 9.2% to 51.2%) and 64.9% (95% CI, 47.5% to 79.8%), respectively (P=.01). The odds ratio for complete or partial response to chemotherapy for mEOC was 0.19 (95% CI, 0.06 to 0.66; P=.009) compared with other histologic subtypes of EOC. Median progression-free survival was 5.7 months (95% CI, 1.9 to 9.6 months) versus 14.1 months (95% CI, 12.0 to 16.2 months; P<.001) and overall survival was 12.0 months (95% CI, 8.0 to 15.6 months) versus 36.7 months (95% CI, 25.2 to 48.2 months; P<.001) for cases and controls, respectively. The hazard ratio for progression and death was 2.94 (95% CI, 1.71 to 5.07; P<.001) and 3.08 (95% CI, 1.69 to 5.6; P<.001), respectively, for mEOC patients as compared with controls. CONCLUSION: Patients with advanced mEOC have a poorer response to platinum-based first-line chemotherapy compared with patients with other histologic subtypes of EOC, and their survival is worse. Specific alternative therapeutic approaches should be sought for this group of patients, perhaps involving fluorouracil-based chemotherapy. 相似文献
36.
The effect of high intakes of casein and casein phosphopeptide on calcium absorption in the rat 总被引:2,自引:0,他引:2
Bennett T Desmond A Harrington M McDonagh D FitzGerald R Flynn A Cashman KD 《The British journal of nutrition》2000,83(6):673-680
The effect of the level or source of dietary protein or protein-derived peptides on Ca absorption is not well understood. We determined, therefore, the influence of habitual dietary casein level, meal casein and meal casein phosphopeptide (CPP) on Ca absorption in the rat. True fractional Ca absorption was investigated in male 7-week-old rats, Wistar strain, in three separate studies using a faecal 47Sc: 47Ca ratio method. In studies A and C, rats (n 8 per group) were fed on a purified diet containing 200 g casein/kg for 2 weeks. Rats were then given a 47Ca-labelled meal (10 g) containing (per kg) either 0, 100, 200, or 300 g casein (study A) or 0, 100, 200, 350 or 500 g CPP (study C). In study B, rats (n 24 per group) were fed on a purified diet containing (per kg) either 200, 350 or 500 g casein for 2 weeks. Each group was then further randomized into three groups (n 8 per group) and given a 47Ca-labelled meal (10 g of the same diet) containing (per kg) either 200, 350 or 500 g casein. Ca absorption from a meal was unaffected by increasing meal casein concentration from 0 to 300 g/kg (study A), but was increased with a meal casein content of 500 g/kg (study B). Fractional Ca absorption decreased with increasing usual dietary casein intake in the range 200-500 g/kg (study B), suggesting intestinal adaptation. Ca absorption was unaffected by inclusion of 100 g CPP/kg in a single meal but was significantly (P < 0.001) reduced by 200, 350 and 500 g CPP/kg meal, with no evident dose-relationship. Thus, while Ca absorption was enhanced by high-casein meals, the mechanism remains unclear. 相似文献
37.
38.
39.
David Leong Rajat Rai Brandon Nguyen Andrew Lee Desmond Yip 《World journal of clinical oncology》2014,5(4):633-645
Non-small-cell lung cancer remains a leading cause of death around the world. For most cases, the only chance of cure comes from resection for localised disease, however relapse rates remain high following surgery. Data has emerged over recent years regarding the utility of adjuvant chemotherapy for improving disease-free and overall survival of patients following curative resection. This paper reviews the clinical trials that have been conducted in this area along with the studies integrating radiation therapy in the adjuvant setting. The role of prognostic gene signatures are reviewed as well as ongoing clinical trials including those incorporating biological or targeted therapies. 相似文献
40.
Gráinne Lennon áine Balfe Helen Earley Liam A Devane Aonghus Lavelle Desmond C Winter J Calvin Coffey P Ronan O'Connell 《Gut microbes》2014,5(3):277-285
The colonic mucus gel layer (MGL) is a critical component of the innate immune system acting as a physical barrier to microbes, luminal insults, and toxins. Mucins are the major component of the MGL. Selected microbes have the potential to interact with, bind to, and metabolize mucins. The tolerance of the host to the presence of these microbes is critical to maintaining MGL homeostasis. In disease states such as ulcerative colitis (UC), both the mucosa associated microbes and the constituent MGL mucins have been shown to be altered. Evidence is accumulating that implicates the potential for mucin degrading bacteria to negatively impact the MGL and its stasis. These effects appear more pronounced in UC.
This review is focused on the host-microbiome interactions within the setting of the MGL. Special focus is given to the mucolytic potential of microbes and their interactions in the setting of the colitic colon. 相似文献