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BACKGROUND: Ranitidine 75 mg (Zantac 75) has been shown to be effective for the treatment of pre-existing heartburn symptoms. AIM: To compare the efficacy of dosing ranitidine 75 mg or placebo 30 min prior to a proven heartburn-provoking meal in completely preventing or reducing subsequent heartburn symptoms. METHODS: A randomized, double-blind, parallel methodology was used at nine investigative centres. Following a screening visit, patients ate a standard test meal consisting of chili, chips and a soft drink on two occasions. On the first occasion, patients received single-blind placebo 30 min before the meal. This meal was used to qualify patients and to ensure the onset of a minimum level of heartburn. Patients who qualified were randomized (n = 284) to receive double-blind ranitidine 75 mg or placebo 30 min before a second test meal administered 4-14 days later at the treatment visit. Patients recorded whether heartburn was present and rated heartburn severity by completing visual analogue scales at 15-min intervals over the 4. 5 h meal evaluation periods. RESULTS: Statistically significant differences favouring ranitidine 75 mg were determined for complete prevention of heartburn (P < 0.006), heartburn severity area under the curve (P < 0.001), a clinical success end-point (P < 0.001), and all other end-points (P < 0.001). CONCLUSIONS: These data clearly demonstrate that ranitidine 75 mg is effective in completely preventing or decreasing heartburn when administered 30 min prior to a provocative meal.  相似文献   
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Abstract: We report the first case of fatal anthrax meningoencephalitis in Hong Kong over the past 60 years. A 13 year-old boy presented with right lower quadrant pain, diarrhoea and progressive headache. Lumbar puncture yielded gram positive bacilli initially thought to be Bacillus cereus, a contaminant. He was treated with ampicillin and cefotaxime, but died 3 days after hospitalization. The organism isolated from blood and cerebrospinal fluid was later identified as Bacillus anthracis.  相似文献   
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OBJECTIVE: Because the survival rate has increased for extremely low birth weight neonates, many have raised the concern that the rate of developmental disability among survivors will also increase. To address this concern, we analyzed changes over time in survival and major neurosensory impairment in a sample of extremely low birth weight infants born between July 1, 1979, and June 30, 1994. METHODS: The study sample included 513 infants with birth weights of 501 to 800 g who were cared for in either of the two neonatal intensive care units that serve a 17-county region in northwest North Carolina and who were born to mothers residing in that region. At 1 year of age (corrected for gestation), survivors were examined by a pediatrician and were tested using the Bayley Scales of Infant Development. Major neurosensory impairment was defined as cerebral palsy, a Bayley Mental Developmental Index <68, or blindness. A total of 209/216 (97%) of survivors were examined at 1 year of age. Epoch of birth was defined as follows: epoch 1, July 1, 1979 to June 30, 1984; epoch 2, July 1, 1984 to June 30, 1989; and epoch 3, July 1, 1989 to June 30, 1994. RESULTS: Survival rates for epochs 1, 2, and 3 were, respectively, 24/120 (20%), 63/175 (36%), and 129/218 (59%). In contrast, the proportions with a major neurosensory impairment did not increase over time; rates for successive epochs were 6/24 (25%), 17/61 (28%), and 26/124 (21%). Rates of cerebral palsy were 3/24 (13%), 12/61 (20%), and 9/124 (7%); rates of delayed mental development were 4/24 (17%), 12/61 (20%), and 17/124 (14%); and rates of blindness were 2/24 (8%), 0/62, and 5/124 (4%), respectively. CONCLUSIONS: This analysis suggests that the increasing survival of extremely low birth weight neonates since the late 1970s has not resulted in an increased rate of major developmental problems identifiable at 1 year of age.  相似文献   
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Objective. The purpose of this investigation is to elucidate the sonographic features of abnormal major cranial sutures. Materials and methods. Eight excised synostosed suture specimens were evaluated. The high-resolution sonographic appearance was correlated with the histological section, plain radiographs, CT and MRI. Diastatic and molded sutures were also evaluated with sonography and compared with the normal cranial suture appearance. Results. Synostosed sutures demonstrated one or more of the following features: (a) loss of echo-poor fibrous gap between bony plates (five sagittal and coronal synostoses); (b) irregular thickened inner sutural margin (three lambdoid synostoses); (c) loss of bevelled edge (one lambdoid synostosis); (d) asymmetric anterior fontanelle (one coronal synostosis). Cranial molding results in an overlap of echogenic bony plates. Sutural width (the distance between bony plates) is increased in cases of elevated intracranial pressure. Conclusion. Sonography is an inexpensive, radiation-free modality which can confirm synostosis versus molding versus an underlying intracranial lesion as a cause of plagiocephaly. The high-resolution sonographic images also provide a relatively easy means to assess sutural width and may provide information in regard to increased intracranial pressure. Received: 24 March 1997 Accepted: 25 September 1997  相似文献   
6.
Interruption of the contrast column during inspiration can lead to non‐diagnostic CT pulmonary angiograms. The importance of this artefact will increase with more CT studies being performed for pulmonary embolism on multidetector row CT. We describe here an instance of such an artefact and discuss its aetiology.  相似文献   
7.
Abstract   Gastroesophageal reflux disease (GERD) is a common disease in the West, which now appears to be also increasing in prevalence in the Asian Pacific region. The reasons for this changing epidemiology are two-fold: an increased awareness among doctors and patients, and/or a true increase in the prevalence of the disease. Prevalence rates of reflux esophagitis (RE) of up to 16% and prevalence of GERD symptoms of up to 9% have been reported in the Asian population. However, the frequency of strictures and Barrett's esophagus remain very low. Non-erosive reflux disease (NERD) appears to be the most common form of GERD among Asian patients accounting for 50–70% of cases with GERD. Among Asian patients differences can also be discerned among different ethnic groups. For example, in Malaysia where a multiracial society exists, RE is significantly more common among Indians compared to Chinese and Malays whereas NERD is more frequently seen in the Indian and Malays compared to the Chinese. The reasons for these differences are not known but may indicate both genetic factors and environmental factors peculiar to the particular racial group. GERD has also been increasing in the region demonstrating a time-lag phenomenon compared to the West. Differing predisposition to GERD among different ethnic groups would mean that such an increase would be more prominent among certain racial groups.  相似文献   
8.
Colorectal carcinoma is one of the commonest solid organ tumors in the world and its prevalence appears to be increasing in Asia. Recently, there has been much interest in various chemotherapeutic agents for the management of this condition, in particular nonsteroidal anti‐inflammatory drugs (NSAIDs). There is a large amount of data that suggest traditional NSAIDs, as well as the new cyclooxygenase (COX)‐2 selective inhibitors such as rofecoxib and celecoxib, have a role in the setting of primary and secondary prevention, and adjuvant therapy of both sporadic colorectal carcinoma and familial adenomatous polyposis. This review examines some of this data, as well as the potential problems and limitations of using these agents, particularly in light of the recent withdrawal of rofecoxib.  相似文献   
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Inflammatory bowel disease (IBD) has long been considered a disease that affects predominantly a Western population. The incidence and prevalence rates from Asian populations are much lower in comparison. More recent data, however, have shown significantly higher rates in Asians and time trend studies have shown an increase in the incidence of ulcerative colitis (UC) and a similar but lower rise in Crohn's disease (CD). The epidemiological changes that are taking place mirror that of the Western experience seen 50 years previously and seem to occur in parallel with the rapid socioeconomic development taking place in Asia. It appears that certain racial groups are more prone than others to develop IBD. For instance, Indians in South‐East Asia have higher rates compared to Chinese and Malays. While there is host genetic predisposition, environmental factor(s) may be responsible for this difference. Migrant studies of South Asians in the UK, where second‐generation immigrants have assumed incidence rates as high as the indigenous whites and Asian Jews who develop high incidence rates comparable to Jews from Europe or North America in Israel point to the role of environmental factors. It is unclear which specific factors are responsible. Studies have suggested a change in diet to a more Westernized one may underlie this epidemiological change in the Asian population. It is likely that there are racial groups amongst Asians who are more susceptible to IBD and who will demonstrate a higher frequency of IBD when exposed to putative environmental factors.  相似文献   
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