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In 1978, China decided to reform its economy and since then has gradually opened up to the world. The economy has grown rapidly at an average of 9.8% per year from 1978 to 1994. Medical expenditure, especially for drugs, has grown even more rapidly. The increase in medical expenditure can be attributed to changing disease patterns, a higher proportion of older people in the population and fee-for-service incentives for hospitals. Due to the changing economic system and higher cost of health care, the Chinese government has reformed its health care system, including its health and drug policy. The drug policy reform has led to more comprehensive policy elements, including registration, production, distribution, utilization and administration. As a part of drug policy reform, the drug distribution network has also been changed, from a centrally controlled supply system (push system) to a market-oriented demand system (pull system). Hospitals can now purchase drugs directly from drug companies, factories and retailers, leading to increased price competition. Patients have easier access to drugs as more drugs are available on the market. At the same time, this has also entailed negative effects. The old drug administrative system is not suitable for the new drug distribution network. It is easy for people to get drugs on the market and this can lead to overuse and misuse. Marketing factors have influenced drug distribution so strongly that there is a risk of fake or low quality drugs being distributed. The government has taken some measures to fight these negative effects. This paper describes the drug policy reform in China, particularly the distribution of drugs to health care facilities.  相似文献   
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The anti-HIV drug 3'-azido-3'-deoxythymidine (AZT) is used successfully for reduction of perinatal viral transmission. However toxic side effects including carcinogenesis are possible. To test this, pregnant CD-1 Swiss mice were given 25.0 or 12.5 mg AZT on gestation days 12-18. Previously we reported an increase in lung, liver, and female reproductive system tumors in offspring euthanized at 1 year (Olivero et al., J. Natl. Cancer Inst. 89, 1602-1608, 1997). Findings for all remaining offspring up to 2 years old are reported here. AZT effects were most prominent in female offspring, with a significant threefold increase in lung tumors, a reduction in lymphoblastic and follicle center cell lymphomas, and a significant increase in histiocytic sarcomas (0 in controls, 3% after low-dose AZT, and 8% after high-dose AZT, p = 0.022). Dose-dependent incidences of mammary gland, ovarian, and seminal vesicle tumors were low but significant: 0/106 controls, 3/105 low-dose, and 8/105 high-dose mice presented one of these neoplasms (p = 0.0025). Incidences of females showing any clearly AZT-related neoplasm, in lung, liver, ovary, or mammary gland or histiocytic sarcoma, in the second year, were 12/32 after the low dose and 14/27 after the high dose vs 3/23 controls (p = 0.0045). Also, the sensitivity of neonatal mice was assessed by administration of 25, 50, 100, or 200 mg/kg AZT on postnatal days 1 through 8. The effects at 2 years were similar to those seen after transplacental exposure, with significant increases in lung, liver, and mammary tumors in females. The results confirm that AZT is a moderately effective perinatal carcinogen in mice, targeting several tissue types.  相似文献   
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Objectives. Mexican Americans (MAs), compared to white non‐Hispanics (WNHs), have higher rates of biliary disease, noninsulin dependent diabetes, and endstage renal disease but lower rates of lung cancer, hip fractures, and mortality from coronary heart disease. Relatively little research has been done to identify other ethnic differences in disease incidence. We used surgical procedure rates to confirm known ethnic differences and to explore our clinical suspicion that MAs have higher rates of appendectomy than WNHs.

Methods. We used a registry of surgical procedures at two teaching hospitals in South Texas to calculate proportional operation ratios (PORs) for MAs versus WNHs. These two hospitals are the primary source of acute hospital care for the indigent in the area. The POR is arithmetically identical to proportional incidence and mortality ratios.

Results. MAs underwent appendectomy proportionally more often than WNHs at both hospitals (POR = 1.41 and 1.75, p < 0.0001). Other significant PORs were consistent with known ethnic disease differences in biliary tract operations, vascular access for chronic hemodialysis, lung cancer, and coronary artery bypass.

Conclusions. These findings support the hypothesis that MAs may undergo appendectomy more often than WNHs and so may be at higher risk of appendicitis.  相似文献   

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The purpose of the present study was to identify a subset of high-risk patients among surgically treated node-positive patients with stage IB and IIA cervical carcinoma. From 1982 through 1991, 334 patients underwent radical hysterectomy for FIGO stage IB and IIA cervical carcinoma. In 68 patients pathological analysis of the surgical specimen revealed positive pelvic nodes. In this group, a Cox proportional hazard analysis was performed to examine the prognostic significance of clinicopathological variables. Only for adenocarcinoma (P= 0.002) and parametrium infiltration (P= 0.003) was evidence of an association with prognosis found. Based on these two factors, patients with positive pelvic nodes were categorized into a low-risk group (squamous cell carcinoma without parametrium infiltration,N= 33) and a high-risk group (squamous cell carcinoma with parametrium infiltration or adenocarcinoma,N= 34). The 5-year disease-specific survival in the low-risk group was 94% compared with 60% in the high-risk group (P= 0.003). For patients in the high-risk group, there is an urgent need for alternative adjuvant treatment to improve outcome.  相似文献   
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Diwan  BA; Anderson  LM; Ward  JM 《Carcinogenesis》1997,18(10):2009-2014
Tamoxifen (TAM) is widely used as adjuvant breast cancer therapy after surgery and as a chemopreventive agent in women of child-bearing age. However, TAM therapy has been shown to result in an increased incidence of endometrial carcinoma in women. The present study was designed to investigate the effects of TAM (5 mg/kg and 7.5 mg/kg body wt) given i.g. to pregnant CD-1 mice (1x/day, days 12 through 18 of gestation) on their female offspring. Progressive proliferative hyperplasia of the oviduct was frequently seen in TAM-exposed offspring, reaching 100% incidence by 52 weeks in both treatment groups. These females also developed progressive proliferative uterine lesions, including moderate/severe cystic endometrial hyperplasia (34-50%) and polypoid adenomas (27-30%) between 53 and 78 weeks. Deciduomas (15%) occurred at young ages (12 and 24 weeks) while leiomyomas (14%), a malignant leiomyosarcoma, and ovarian granulosa cell tumors (14%), were found between 72 and 78 weeks. Our findings thus suggest a strong association between transplacental TAM and reproductive tract abnormalities in female CD-1 mice.   相似文献   
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Background. Klippel-Feil syndrome (KFS) is characterised by congenital vertebral fusion of the cervical spine and a wide spectrum of associated anomalies. KFS has often been considered a sporadic syndrome. However, since the publication of the original KFS classification early this century, a number of KFS families have indicated heterogeneity complicated by a broad range of variable expression. Objective. The two major objectives of this study were (1) to identify differences and similarities in the postnatal appearance, morphology, position and inheritance of vertebral fusions within and between KFS families and (2) to establish a new KFS classification focussed on KFS aetiology. Materials and methods. Vertebral fusions were assessed via spinal radiography. Chromosomal karyotypes were performed using routine cytogenetics. Results. The medical histories of three KFS families are presented. The postnatal time, position and appearance of vertebral fusions, associated anomalies and mode of inheritance were different for the three KFS families. Four classes of KFS are described in a comprehensive classification table that allays much of the uncertainty arising from KFS heterogeneity and variable expression. Conclusion. We have described four different KFS classes (KF1–4) within a comprehensive classification that addresses KFS genetic heterogeneity. The position of vertebral fusions in the cervical spine and their incidence within affected families are delineating features of KFS. Received: 10 October 1997 Accepted: 20 April 1998  相似文献   
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