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91.
The possible association between the risk of rectal cancer and hardness levels in drinking water from municipal supplies was investigated in a matched case-control study in Taiwan. All eligible rectal cancer deaths (986 cases) of Taiwan residents from 1990 through 1994 were compared with deaths from other causes (986 controls), and the hardness levels of the drinking water used by these residents were determined. Data on water hardness throughout Taiwan were collected from Taiwan Water Supply Corporation (TWSC). The control group consisted of people who died from other causes and the controls were pair matched to the cases by sex, year of birth, and year of death. The results show a significant negative relationship between drinking water hardness and rectal cancer mortality. Odds ratio and 95% confidence intervals were 1.24 (1.01-1. 55) and 1.38 (1.10-1.73), respectively, for exposure to moderately hard water and soft water compared with the use of hard water. Trend analyses showed an increasing odds ratio for rectal cancer with decreasing levels of hardness in drinking water. This is an important finding for the Taiwan water industry and human health.  相似文献   
92.
BACKGROUND/AIM: A mechanism suggested to cause injury to preserved organs is the generation of oxygen free radicals. Lipid peroxidation is one of the biological damages caused by oxygen free radicals. It is our aim to investigate whether magnolol, a strong antioxidant, suppresses the generation of oxygen free radicals and improves the viability of cold-preserved warm-reperfused rat livers. MATERIALS AND METHODS: In vitro lipid peroxidation was induced in rat hepatic mitochondria with ADP and FeSO4. The inhibitory effect of magnolol on lipid peroxidation was measured with oxygen consumption and malondialdehyde (MDA) formation. Subsequently, we preserved and reperfused rat livers in preservation solutions that contained magnolol. The hepatic enzymes and liver MDA were measured to assess the protective effect of magnolol on isolated rat livers. RESULTS: In rat hepatic mitochondria, magnolol was 470 times more potent than alpha-tocopherol in inhibiting oxygen consumption and 340 times more potent than alpha-tocopherol in inhibiting MDA formation. Addition of magnolol to Ringer's lactate solution had a protective effect, in terms of MDA formation and leakage of hepatic enzymes, on warm-reperfused but not cold-stored liver tissue. Addition of magnolol to University of Wisconsin (UW) solution, a widely used preservation solution, did not modify the effect of this solution on isolated liver tissues. CONCLUSIONS: We conclude that magnolol is an effective antioxidant and suppresses lipid peroxidation in rat liver mitochondria and can be used as a rinsing solution in protecting transplanted organs from lipid peroxidation during reperfusion, especially for those organs not preserved with UW solution.  相似文献   
93.
OBJECTIVES: The aim of this study is to evaluate the efficacy and tolerability of sertraline in patients with major depression who have failed to respond to an adequate trial of moclobemide. METHOD: Sixty-three patients with major depression who had discontinued moclobemide within the last 6 weeks due to lack of efficacy were recruited from multiple psychiatric services in Victoria and Queensland. After a wash-out period, patients were treated with sertraline 50 mg once daily for 4 weeks. If there was an insufficient response, the dose was titrated upwards to a maximum of 200 mg/day, with 2 weeks at each dosage level. By the end of the study, patients had received a fixed dose of sertraline for 8 weeks. The main outcome measures were the 17-item Hamilton Rating Scale for Depression (HAMD) and Clinical Global Impression (CGI) scales. Secondary outcome measures included the Montgomery-Asberg Depression Rating Scale (MADRS) and Beck Depression Inventory (BDI). RESULTS: Of the 62 intention-to-treat patients enrolled, 48 (77%) responded to sertraline (i.e. experienced > or =50% reduction in HAMD total score from baseline and had a final HAMD score of < or =17). Fifty-four (87%) patients were at least 'minimally improved' on the CGI scale. There were also significant improvements in mean total MADRS and BDI scores. Sertraline was well tolerated. Adverse events were reported by 84% of patients, but only 5% withdrew due to adverse events. CONCLUSIONS: This study shows that patients with major depression who have failed to respond to moclobemide can generally be treated successfully with sertraline.  相似文献   
94.
95.
We investigated the association between schizophrenic psychosis and an intronic polymorphism of the presenilin-1 (PS1) gene in a Chinese population. Schizophrenic and control groups had similar PS1 genotype distributions and allele frequencies, indicating that this polymorphism may not be involved in the development of schizophrenia.  相似文献   
96.
A splint has been designed to correct the congenital clasped thumb. It is like a short opponens splint that can keep the thumb in a position of abduction and extension without limiting wrist movement. The application of the splint was easy and adjustment for fit could be made at each visit if necessary. The device has been used in 11 infant patients (17 thumbs) with congenital clasped thumb of the supple type. The functional results were excellent in 15 of 17 thumbs, and the other two were good according to the grading system of Weckesser et al. (1968).  相似文献   
97.
Chiu DT 《Hand Clinics》1999,15(4):667-71, ix
Autogenous venous nerve conduit (AVNC) has evolved from an experimental idea to a clinical reality over the last two decades. The effectiveness of AVNC for reconstruction of a peripheral nerve with a nerve gap of less than 3 cm has been established and confirmed. An exciting application of this technique in the near future is to use the conduit as a vehicle for moderation and modulation of the cellular and molecular ambience for nerve regeneration.  相似文献   
98.
Studies of minority ethnic women and cancer screening have, in the past, suffered from many theoretical and methodological weaknesses. In addition, no attempts have been made to study the complexity of the issue involved in the intercultural context, or the possible contribution of women's experiences to low uptake rates. In order to further our understanding of the issues, an alternative approach, participatory action research (PAR), was adopted to identify factors that might have contributed to the persistently low participation of minority ethnic women in the cervical screening programme, and address them collaboratively. This paper presents the key findings of the ‘problem identification' phase of the project. Using mainly the focus-group method, it explores both smear takers' and minority ethnic women's perceptions and experiences of cervical screening. Data suggest that there was a divergence in perceptions held by these groups regarding cervical screening, which contributed to negative experiences for both groups. There is also clear evidence of dysfunctional clinical communication arising from these differing perceptions. Opportunistic screening at post-natal examination adopted by many general practices appeared to have perpetuated the perceptions that the majority of minority ethnic women held about the purpose of the smear test. Compounded by language differences, the majority of women who had undergone smear testing understood neither the purpose of screening programme nor the procedure of the test. This has clear implications for promoting regular uptake, and more importantly for informed consent and choice.  相似文献   
99.
Dihydropyrimidinones such as compound 12 exhibited high binding affinity and subtype selectivity for the cloned human alpha(1a) receptor. Systematic modifications of 12 led to identification of highly potent and subtype-selective compounds such as (+)-30 and (+)-103, with high binding affinity (K(i) = 0.2 nM) for alpha(1a) receptor and greater than 1500-fold selectivity over alpha(1b) and alpha(1d) adrenoceptors. The compounds were found to be functional antagonists in human, rat, and dog prostate tissues. Compound (+)-103 exhibited excellent selectively to inhibit intraurethral pressure (IUP) as compared to lowering diastolic blood pressure (DBP) in mongrel dogs (K(b)(DBP)/K(b)(IUP) = 40) suggesting uroselectivity for alpha(1a)-selective compounds.  相似文献   
100.
Acute catatonic syndromes occurring in the context of various medical and neuropsychiatric conditions, including schizophrenia, have been shown to respond well to benzodiazepines (BZD). However, there have been no studies specifically designed to address the BZD treatment response of persistent catatonic states. Eighteen patients with clinically stable chronic schizophrenia, who also displayed enduring catatonic features, underwent a 12-week long, random assignment, double-blind, placebo-controlled cross-over trial with lorazepam (6 mg/day). A comprehensive assessment, including the subjects’ clinical and motor (catatonic as well as drug-induced movement disorders) condition, was performed at baseline and four weekly intervals thereafter. Pre-existing medication was kept constant throughout the study. Lorazepam had no effect on the subjects’catatonic signs and symptoms, suggesting that acute and chronic catatonic syndromes associated with schizophrenic illness might have a different neurobiological basis. Received: 25 May 1998/Final version: 22 September 1998  相似文献   
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