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11.
Age and gender interactions on verbal memory performance.   总被引:1,自引:0,他引:1  
Age and gender effects on verbal episodic memory are well established. However, the possibility of interactions between age and gender has been raised by studies linking estrogen and verbal memory performance, and by research suggesting gender differences in age-related cortical atrophy. We evaluated whether age by gender interactions in verbal memory were present. Subjects within three years of the median age of menopause were excluded from a large cohort of normal subjects, resulting in a younger sample (16-47 years) of 288 men and 285 women, and an older sample (55-89 years) of 201 men and 245 women. All subjects were administered the CVLT-2, a multiple-trial list-learning task. Verbal memory was negatively correlated with age for younger men, older men, and older women, but not for younger women. Multivariate analyses indicated age by gender interactions on memory for the younger group but not the older group. Results indicate that verbal memory declines with age for younger men but not younger women, whereas both older men and older women show age-related declines. These findings are consistent with hypotheses linking estrogen and verbal memory performance, and with imaging data suggesting that age-related hippocampal atrophy is found in younger men but not younger women. The role of estrogen on cognition in normal aging warrants further study.  相似文献   
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OBJECTIVE: To evaluate the prevalence and clinico/prognostic significance of the presence of pre-invasive lesions in patients resected for primary lung neoplasm. METHODS: From 1993 to 2002, 1090 patients received resection for primary lung carcinomas. Of these, 73 presented an associated pre-invasive lesion in the surgical specimen distant from the primary tumour. Classification of pre-invasive lesions included Atypical Adenomatous Hyperplasia (AAH); Carcinoma In Situ (CIS) either diffuse or at the bronchial resection margin; Diffuse Idiopathic Pulmonary Neuroendocrine Cell Hyperplasia (DIPNECH). Correlation between the presence of pre-invasive lesion and the following variables were calculated by logistic regression analysis: sex, age, median tumour size, histology, histologic differentiation, histologic evidence of invasiveness (vascular and perineural invasion), peritumoural lymphocytic infiltrate, pTNM, lobe location, history of previous malignancy. Survival rates were computed using Kaplan-Meier method and survival differences with the total patient population of resected lung carcinomas were tested using the log-rank method. RESULTS: There were 28 AAH, 42 CIS (5 at the bronchial resection margin) and 3 DIPNECH. Histology of the primary tumor included bronchioloalveolar carcinoma (9 patients), adenocarcinoma (19), squamous cell carcinoma (39), typical carcinoid tumour (3) and adenosquamous carcinoma (3). Overall prevalence of pre-invasive lesion was 6.7%. A strong correlation was found between the presence of AAH and the co-existence of either adenocarcinoma, bronchioloalveolar carcinoma or mixed adenocarcinoma-containing tumours (P = 0.00002) between CIS and squamous cell carcinoma (P = 0.009) and between DIPNECH and carcinoid tumours (P = 0.001). No significant correlation was found between the presence of any type of pre-invasive lesion and sex, age, median tumour size, histologic differentiation, histologic evidence of invasiveness, pTNM, lobe location and history of previous malignancy or the probability to develop a second primary lung carcinoma in the remaining lobe(s) after resection. Survival rates in the patients with AAH and CIS were not significantly different from those of patients without pre-invasive lesion (P = 0.3 and P = 0.1). CONCLUSIONS: Associated pre-invasive lesions in patients resected for primary lung neoplasms are not infrequent. AAH is associated with adenocarcinoma, CIS with squamous cell carcinoma, DIPNECH with typical carcinoid tumours. Our experience indicates that in these patients histology, stage distribution and survival do not differ from the total population of resected patients with lung tumors.  相似文献   
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N C Dean  W C Amend  M A Matthay 《Chest》1987,91(4):619-620
A 21-year-old man developed the adult respiratory distress syndrome (ARDS) within five hours of receiving antilymphocyte globulin. No other identifiable cause of ARDS was present. The mechanism for development of acute lung injury is unknown, but may be related either to direct lung cytotoxicity or to complement-mediated leukocyte and platelet destruction with secondary lung injury from inflammatory mediators.  相似文献   
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Although major tissue trauma produces profound depression of cell-mediated immunity, it is not known whether surgical trauma (i.e., midline laparotomy) has any adverse effect on the antigen presentation function and membrane interleukin-1 (IL-1) activity of peritoneal macrophages. To study this, C3H/HEJ (endotoxin-tolerant) mice were anesthetized. An approximately 1-inch midline abdominal incision was made, followed by abdominal closure. On days 1, 3, 5, and 7, peritoneal macrophages were harvested by means of peritoneal lavage, and antigen presentation capability was tested by incubating various numbers of peritoneal macrophages with 2 X 10(4) D10.G4.1 cells per well in the presence of conalbumin (400 micrograms/ml). The T helper cell clone (D.10.G4.1) proliferates on recognition of conalbumin in the context of Iak and also proliferates in the presence of membrane-bound IL-1 plus concanavalin A. To measure membrane IL-1 expression in peritoneal macrophages, Concanavalin A (10 micrograms/ml) was substituted for conalbumin. Cultures were incubated for 72 hours, pulsed with tritiated thymidine, and harvested. Peritoneal macrophages from laparotomized mice induced significantly less T helper cell proliferation on days 1 and 3 in the antigen presentation assay (37% and 30%, respectively; p less than 0.05) and in the membrane IL-1 assay (14% and 10%, respectively; p less than 0.05) as compared with the control. This difference was not detectable on day 5. More effective antigen presentation capability (167% of control; p less than 0.05) was seen on day 7. Thus laparotomy by itself produces marked depression of both antigen presentation function and membrane IL-1 activity of peritoneal macrophages, which may enhance susceptibility to intra-abdominal sepsis.  相似文献   
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Mechanisms of zinc (Zn) toxicity are incompletely understood and data regarding potential endocrine alterations in Zn toxicity are scarce. To examine mechanisms of Zn toxicity, day-old chicks were pair-fed diets containing 5280 ppm (Hz) or 73 ppm (CON) Zn. Impaired postnatal growth, independent of feed consumption, and multiple endocrinopathies were observed following short-term (1-2 weeks) exposure to the high Zn diet. Reduced levels of serum cholesterol, high-density lipoprotein cholesterol, and growth hormone were associated with HZ feeding. Depressed levels of circulating thyroid hormones and histological evidence that follicle area of thyroids from HZ birds was 63% less than CON indicated that impaired growth of HZ birds may be caused, in part, by reduced thyroidal function.  相似文献   
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An examination of the urinary excretions of 101 normal subjects indicated that the major genetic influence on calcium excretion is a codominant pair of alleles giving rise to three phenotypes, low, intermediate and high (hypercalciuric) excretors. This inference was based on variance, Hardy-Weinberg and segregation analyses. Similar independent gene pairs also appear to influence oxalate and citrate excretion, A 3-locus Hardy-einberg table using estimates of gene frequencies derived from the study of normals suggests that only 3 or 4 leading genes are involved in oxalate stone disease. Strong candidate genes identified from molecular and physiological studies cannot be proposed at present, but it is assumed that they influence the transport of these ions in either the intestine, kidney or both organs. The identification of the genes involved should be facilitated by the reduction of dietary influences on urinary excretions through the use of formula diets.  相似文献   
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Sulfasalazine (SASP) has often been reported to cause serious blood disorders, particularly agranulocytosis; however, little quantitative information is available to estimate the risk or to identify possible modifiers of the risk. We used comprehensive clinical information recorded on office computers by selected general practitioners in Britain to conduct a follow-up study of some 10,000 users of SASP and some 4000 users of mesalazine to estimate the risk of blood disorders associated with these drugs. Overall, the frequency of blood disorders attributable to SASP was 27/10,332 (2.6/1000 users). The risk for SASP users who were treated for arthritic disorders (6.1/1000 users) was some 10 times higher than that for users who were treated for inflammatory bowel disease (0.6/1000 users). There were no cases of blood disorders in users of mesalazine.  相似文献   
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