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101.
102.
In 1998, a case-control study was conducted in Hong Kong on hospital patients with osteoarthritis of the hip (n = 138) and osteoarthritis of the knee (n = 658). Age- and sex-matched controls were recruited consecutively from general practice clinics in the same region. The following three risk factors were found to be associated with osteoarthritis of both the hip and the knee: first, a history of joint injury: for osteoarthritis of the hip, the odds ratio = 25.1 (95% confidence interval (CI): 3.5, 181) in men and 43.3 (95% CI: 11.7, 161) in women; for osteoarthritis of the knee, the odds ratio = 12.1 (95% CI: 3.4, 42.5) in men and 7.6 (95% CI: 3.8, 15.2) in women; second, climbing stairs frequently: for osteoarthritis of the hip, the odds ratio = 12.5 (95% CI: 1.5, 104.3) in men and 2.3 (95% CI: 0.6, 8.1) in women; for osteoarthritis of the knee, the odds ratio = 2.5 (95% CI: 1.0, 6.4) in men and 5.1 (95% CI: 2.5, 10.2) in women; third, lifting heavy weight frequently: for osteoarthritis of the hip, the odds ratio = 3.1 (95% CI: 0.7, 14.3) in men and 2.4 (95% CI: 1.1, 5.3) in women; for osteoarthritis of the knee, the odds ratio = 5.4 (95% CI: 2.4, 12.4) in men and 2.0 (95% CI: 1.2, 3.1) in women. In addition, subjects whose height and weight were in the highest quartile were at increased risk of osteoarthritis of the hip and knee, respectively (p < 0.05).  相似文献   
103.
A new recommendation for maternal weight gain in Chinese women   总被引:9,自引:0,他引:9  
OBJECTIVE: To characterize the distribution of maternal weight gain in Chinese women living in a well-nourished community, to recommend target weight gains from quartile values derived from women with good pregnancy outcomes, and to quantify the risk for adverse pregnancy outcomes encountered among subjects with weight gain outside these recommendations. DESIGN: A retrospective study on maternal anthropometry and pregnancy outcomes was conducted among Chinese women who delivered a singleton pregnancy in a university hospital in Hong Kong. SUBJECTS: Nine hundred eight women who delivered during the study period were identified. Among them, 754 (83%) had complete anthropometry data. The normative distribution of maternal weight gain was derived from 504 women who had a good pregnancy outcome. STATISTICS: Analysis of variance was used to compare total weight gain among women of different prepregnancy weight. Fisher exact test was used in the univariate analysis of the association between risk factors and corresponding adverse pregnancy outcomes. Adjusted odds ratios for adverse outcomes were determined by multiple logistic regression models controlling for the following factors: maternal age, duration of gestation, prepregnancy body mass index (BMI), height, parity, and smoking. RESULTS: A maternal weight-gain chart and recommendations for total weight gains in Chinese women were derived from the distribution of weight gain in subjects with good pregnancy outcomes. The recommended total weight gain was 13 to 16.7 kg, 11 to 16.4 kg, and 7.1 to 14.4 kg respectively for women of low (BMI < 19), moderate (BMI: 19 to 23.5), and high (BMI > 23.5) prepregnancy BMI. Women who did not achieve the lower quartile value had more than twice the risk of having low-birth-weight infants. Those with excessive weight gain were at risk for needing assisted delivery. APPLICATIONS: As maternal anthropometry differs across ethnic groups, different recommendations should be made for specific populations.  相似文献   
104.
Background: Edatrexate and carboplatin are each active single agents in the treatment of non-small-cell lung cancer (NSCLC). Preclinical studies in NSCLC lines have demonstrated schedule-dependent synergy of edatrexate followed by carboplatin. In a phase I trial, we demonstrated the tolerability of this combination, the ability of ice-chip cryotherapy to ameliorate dose-limiting mucositis, and promising activity in NSCLC. This phase II trial (SWOG 9207) was undertaken to investigate the efficacy of this regimen in stage IV NSCLC. Methods: A total of 24 patients with stage IV disease were accrued to this Southwest Oncology Group (SWOG) multicenter study. Treatment consisted of edatrexate 80 mg/m2 (50% dose on day 8) intravenously weekly for 5 weeks, then every other week, and carboplatin 350 mg/m2 every 28 days. Results: Of the 24 patients, 23 were assessable for toxicity and response; one was ineligible for study entry. Myelosuppression was the most significant toxicity; grade 3–4 neutropenia was seen in 8/23 patients. Two patients died of neutropenic sepsis during the first cycle of therapy, in both instances associated with the presence of pleural effusions. Although mild mucositis was common, it was dose-limiting (grade 3) in only three patients. Objective response was observed in 3/23 patients (13%). The median survival time was 7 months, and 30% of patients remained alive at one year. Conclusions: This study suggests that ice-chip cryotherapy is effective in reducing the severity of mucositis typically associated with this edatrexate schedule of administration. However, unexpectedly severe myelosuppression resulted in death from neutropenic sepsis in two patients with third space fluid collections, leading to a protocol amendment to exclude such patients from study entry. Furthermore, response and median survival with this dose schedule of edatrexate and carboplatin do not appear to be improved compared to other chemotherapeutic regimens tested by SWOG in this patient population. Received: 12 August 1996 / Accepted: 8 May 1997  相似文献   
105.
Rogers  AE; Hafer  LJ; Iskander  YS; Yang  S 《Carcinogenesis》1998,19(7):1269-1273
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   
106.
PURPOSE: Lung cancer is the leading cause of cancer deaths in the United States. Non-small-cell lung cancer (NSCLC) accounts for 75% to 85% of lung cancers. CT has been the standard anatomic study for localizing and staging NSCLC, although it is associated only with moderate accuracy. In-111 pentetreotide, a radiolabeled somatostatin analog largely used in the scintigraphic localization of neuroendocrine tumors, has been shown incidentally to identify NSCLC lesions. This observation is important in the workup for metastatic disease for neuroendocrine tumors, because presumed metastatic lesions may actually be second primary tumors of NSCLC. In-111 may also serve as a potentially useful adjunct to CT in the anatomic evaluation of NSCLC. The purpose of this study was to determine the likelihood of detecting and localizing NSCLC using In-111 pentetreotide scintigraphy. MATERIALS AND METHODS: Ten patients with known or possible NSCLC were examined using In-111 pentetreotide. Scans were compared with the patients' previously performed chest radiographs and CT scans. RESULTS: In-111 pentetreotide imaging correctly identified sites of tumor involvement as detected by chest CT and surgery in all 10 patients with NSCLC. CONCLUSION: This study demonstrates the uptake of In-111 pentetreotide by NSCLC. This important observation should be considered in the workup for metastatic disease of neuroendocrine tumors with In-111 pentetreotide, because NSCLC can be a source of false-positive findings. In-111 pentetreotide imaging may also serve as a potentially useful adjunct to CT for identifying obscured or equivocal lesions and as an aid in localizing tissue for biopsy.  相似文献   
107.
Mutual information has been proposed as a criterion for image registration. The criterion is calculated from a two-dimensional grey-scale histogram of the image pair being registered. In this paper we study how sparse sampling can be used to increase speed performance using the registration algorithm of Maes et al. (IEEE Trans Med Imaging 1997; 16: 187-198) with a focus on registration of MRI-SPET brain images. In particular we investigate how sparse sampling and parameters such as the number of bins used for the grey-scale histograms and smoothing of the data prior to registration affect accuracy and robustness of the registration. The method was validated using both simulated and human data. Our results show that sparse sampling introduced local maxima into the mutual information similarity function when the number of bins used for the histograms was large. To speed up registration while retaining robustness, smoothing of the data prior to registration was used and a coarse to fine subsampling protocol, where the number of bins in the histograms were dependent on the subsampling factor, was employed, For the simulated data, the method was able to recover known transformations with an accuracy of about 1 mm. Using the human data, there were no significant differences in the recovered transformation parameters when the suggested subsampling scheme was used compared with when no subsampling was used, but there was a more than tenfold increase in speed. Our results show that, with the appropriate choice of parameters, the method can accurately register MRI-SPET brain images even when very efficient sampling protocols are used.  相似文献   
108.
109.
110.
Lau YE  Cherry JA 《Neuroreport》2000,11(1):27-32
Distribution of the cAMP-specific phosphodiesterase PDE4A was examined in the accessory olfactory system by immunohistochemistry. Adjacent sections through the vomeronasal organ (VNO) and accessory olfactory bulb (AOB) were alternately immunostained with antibodies against PDE4A or the G-protein alpha subunit G(o) alpha, which labels basal VNO neurons, in order to determine whether PDE4A occurs preferentially in one of two segregated VNO pathways. We found that PDE4A strongly labeled apical VNO neurons and rostral AOB glomeruli. There was virtually no overlap in G(o) alpha and PDE4A staining, and there were no regions of the VNO neuroepithelium or AOB glomeruli not labeled by either antibody. These results identify a potential member of the pheromone transduction cascade in apical neurons, and provide further evidence that the VNO consists of functionally distinct pathways.  相似文献   
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