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81.
The origin of paradental cysts is related to inflammatory processes, especially pericoronaritis involving impacted or semi-impacted teeth. The authors present a case of paradental cyst related to lower second molar that did not show clinical evidence of inflammatory process. The main aspects related to its classification, diagnosis and clinical characteristics are also discussed.  相似文献   
82.
The beginning of agriculture is one of the most important developments in human history, with enormous consequences that paved the way for settled life and complex society. Much of the research on the origins of agriculture over the last 40 years has been guided by Flannery's [Flannery, K. V. (1969) in The Domestication and Exploitation of Plants and Animals, eds. Ucko, P. J. & Dimbleby, G. W. (Duckworth, London), pp. 73-100] "broad spectrum revolution" (BSR) hypothesis, which posits that the transition to farming in southwest Asia entailed a period during which foragers broadened their resource base to encompass a wide array of foods that were previously ignored in an attempt to overcome food shortages. Although these resources undoubtedly included plants, nearly all BSR hypothesis-inspired research has focused on animals because of a dearth of Upper Paleolithic archaeobotanical assemblages. Now, however, a collection of >90,000 plant remains, recently recovered from the Stone Age site Ohalo II (23,000 B.P.), Israel, offers insights into the plant foods of the late Upper Paleolithic. The staple foods of this assemblage were wild grasses, pushing back the dietary shift to grains some 10,000 years earlier than previously recognized. Besides the cereals (wild wheat and barley), small-grained grasses made up a large component of the assemblage, indicating that the BSR in the Levant was even broader than originally conceived, encompassing what would have been low-ranked plant foods. Over the next 15,000 years small-grained grasses were gradually replaced by the cereals and ultimately disappeared from the Levantine diet.  相似文献   
83.
Staff at a nurse-managed urban health center conducted a series of art sessions to benefit the community. The authors believe the program's success clearly communicated the relationship between art and community health. As a result of the success of the sessions, plans are in the works to make art a permanent part of the health center's services.  相似文献   
84.
We identified five structurally related dimethane sulfonates with putative selective cytotoxicity in renal cancer cell lines. These compounds have a hydrophobic moiety linked to a predicted alkylating group. A COMPARE analysis with the National Cancer Institute Anticancer Drug Screen standard agent database found significant correlations between the IC50 of the test compounds and the IC50 of alkylating agents (e.g., r = 0.68, P < 0.00001 for chlorambucil). In this report, we examined whether these compounds had activities similar to those of conventional alkylating agents. In cytotoxicity studies, chlorambucil-resistant Walker rat carcinoma cells were 4- to 11-fold cross-resistant to the test compounds compared with 14-fold resistant to chlorambucil. To determine effects on cell cycle progression, renal cell carcinoma (RCC) line 109 was labeled with bromodeoxyuridine prior to drug treatment. Complete cell cycle arrest occurred in cells treated with an IC90 dose of NSC 268965. p53 protein levels increased as much as 5.7-fold in RCC line 109 and as much as 20.4-fold in breast cancer line MCF-7 following an 18-hour drug exposure. Finally, DNA-protein cross-links were found following a 6-hour pretreatment with all compounds. Thus, the dimethane sulfonate analogues have properties expected of some alkylating agents but, unlike conventional alkylating agents, appear to possess activity against RCC.  相似文献   
85.
BACKGROUND: Mechanisms contributing to suicidal behaviour may differ according to how far individuals have progressed through the suicidal process. METHODS: Lifetime and subsequent 12-month cumulative incidences were obtained of death ideation, death wishes, suicide contemplation and deliberate self-harm in a survey (n=5618) of Dutch adults. Mokken's scale analysis was used to examine whether these were compatible with underlying lifetime and 12-month severity dimensions of suicidality. Sociodemographic details and personality traits, 12-month occurrence of negative life events, hopelessness and CIDI-generated DSM-III-R diagnoses were obtained. Ordered logistic regression was used to examine whether the effects of these on the 12-month incidence of suicidality differed by individuals' prior lifetime history of suicidality. RESULTS: Mental illness was more strongly associated with 12-months' suicidality in the presence (ordered logistic regression coefficient 0.80, 95% confidence interval 0.48-1.12) than the absence of previous suicidality (0.49 [0.25-0.74]). The reverse obtained for negative life events (0.18 [0.08-0.29] vs. 0.40 [0.33-0.48], respectively) and a number of sociodemographic risk factors. Female gender was a risk factor for 12-months' suicidality (0.47 [0.28-0.66]) only when it was first-onset. LIMITATIONS: Completed suicides were not recorded. Self-report of lifetime suicidal behaviour may be biased. CONCLUSION: Environmental influences on suicidal behaviour are most pronounced early in the suicidal process which, after it has progressed, becomes more autonomous and intricately linked with mental illness and depression in particular. Men progress through the suicidal process faster than women. Management of suicidal behaviour depends on the stage of the process the person is at.  相似文献   
86.
The aim of this review is to identify assessment instruments that can be used for analyzing sequences and can be applied to research into nurse-patient communication in cancer care. A systematic search of the literature revealed a variety of methods and instruments applicable to studies recording nurse-patient interaction. The studies that were qualitative in nature offered valuable information on observational research in general, on procedures relating to informed consent and observational arrangements in nursing practice. The quantitative studies provided an insight into the content and structure of the interaction by describing communication concepts or by frequency counts of previously determined behaviours. Systematic research into interaction sequences was not found. However, some of the quantitative instruments identified could be adapted for this purpose. The complexity and time-consuming nature of observational research highlight the need for efficiency. For instance a combination of quantitative and qualitative instruments could be considered.  相似文献   
87.
Invasive fungal rhinosinusitis in immunocompromised patients   总被引:2,自引:0,他引:2  
INTRODUCTION: Invasive fungal rhinosinusitis (IFR) is one of the most important causes of morbidity and mortality in immunocompromised patients, principally those with cellular immunodeficiency, with mortality ranging from 50 to 80%. Prophylaxis and early diagnosis increase the chances of successful treatment. STUDY DESIGN: Clinical prospective randomized study. AIM: To present cases of IFR and to compare them with data reported in the literature. MATERIAL AND METHODS: Analysis of eleven cases of IFR confirmed by pathologist examination. RESULTS: Aspergillus was found to be the most prevalent pathogen. Symptoms ranged from high fever in most cases to nasal discharge, ulceration of the nasal mucosa, headache and periorbital edema. CONCLUSION: The combination of amphotericin B and endoscopic surgery, associated or not with Caldwell-Luc surgery, showed good results. The use of liposomal amphotericin B also presented a satisfactory outcome.  相似文献   
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