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排序方式: 共有350条查询结果,搜索用时 15 毫秒
1.
2.
With estimates as high as 1.8 million individuals infected with human immunodeficiency virus (HIV) in the United States, the majority asymptomatic, it is crucial that all physicians routinely use adequate disinfection procedures for medical instruments. The protosigmoidoscopic disinfection procedures used by US family physicians were evaluated for adequacy in inactivating HIV. Sixty-seven percent of 1,585 randomly selected American Academy of Family Physicians members completed a mail survey regarding these procedures. Comparing procedures used with those recommended by the Centers for Disease Control or documented to inactivate HIV, 32.4 percent were judged to be appropriate procedures; 54.4 percent of the procedures were not tested or recommended; and 13.2 percent used appropriate solutions but at inadequate concentrations or exposure times. Therefore, a substantial proportion of US family physicians performing endoscopic procedures use disinfection procedures that may not inactivate HIV. The ever-increasing prevalence of HIV demands that standardized adequate disinfection procedures be implemented by all physicians to prevent the potential nosocomial spread of HIV. 相似文献
3.
Intestinal schistosomiasis japonica: CT-pathologic correlation 总被引:1,自引:0,他引:1
Lee RC; Chiang JH; Chou YH; Rubesin SE; Wu HP; Jeng WC; Hsu CC; Tiu CM; Chang T 《Radiology》1994,193(2):539
4.
To investigate the incidence of use of the flexible and rigid proctosigmoidoscopes by family physicians, a questionnaire was mailed to 1,585 randomly selected members of the American Academy of Family Physicians. Of the total of 1,057 respondents, 48 percent performed sigmoidoscopy, with 30 percent performing flexible sigmoidoscopy, 31 percent performing rigid sigmoidoscopy, and 48 percent performing at least one of the procedures. Younger physicians were found to be more likely to perform flexible sigmoidoscopy, as were physicians who practice in communities of fewer than 500,000 population. Nationwide, more of the flexible procedures are performed in private offices than in the hospital. Physicians in communities of less than 500,000, however, are more likely to use the flexible sigmoidoscope in a hospital setting than are physicians in larger urban areas [corrected]. Board-certified physicians were more likely to perform one or both procedures than were noncertified physicians. 相似文献
5.
6.
Gene conversion is a likely cause of mutation in PKD1 总被引:3,自引:0,他引:3
Watnick TJ; Gandolph MA; Weber H; Neumann HP; Germino GG 《Human molecular genetics》1998,7(8):1239-1243
Approximately 70% of the gene responsible for the most common form of
autosomal dominant polycystic kidney disease ( PKD1 ) is replicated in
several highly homologous copies located more proximally on chromosome 16.
We recently have described a novel technique for mutation detection in the
duplicated region of PKD1 that circumvents the difficulties posed by these
homologs. We have used this method to identify two patients with a nearly
identical cluster of base pair substitutions in exon 23. Since pseudogenes
are known to be reservoirs for mutation via gene conversion events for a
number of other diseases, we decided to test whether these sequence
differences in PKD1 could have arisen as a result of this mechanism. Using
changes in restriction digest patterns, we were able to show that these
sequence substitutions are also present in N23HA, a rodent-human somatic
cell hybrid that contains only the PKD1 homologs. Moreover, these changes
were also detected in total DNA from several affected and unaffected
individuals that did not harbor this mutation in their PKD1 gene copy. This
is the first example of gene conversion in PKD1 , and our findings
highlight the importance of using gene-specific reagents in defining PKD1
mutations.
相似文献
7.
Blanchard K Proverbs-Singh T Katner A Lifsey D Pollard S Rayford W 《Journal of the National Medical Association》2005,97(10):1378-1385
OBJECTIVES: To understand women's knowledge, attitudes and beliefs about prostate cancer. METHODS: A survey was self-administered to 324 women age >18 years. It contained 42 questions that assessed women's knowledge about prostate cancer, possible risk factors, and opinions regarding screening and early detection. Women were grouped as married or unmarried for convenient comparisons. Chi-squared and F statistics were performed. RESULTS: Ninety-seven percent of married women reported having some influence over the healthcare decisions of their spouse. Married women's worst fear about their spouse or family member's diagnosis of prostate cancer was death. The most important benefit of prostate cancer screening was the possibility of cure, while the main hindrance was fear of the digital rectal exam. Marital status, age, educational level and income were all significantly associated with women's knowledge about prostate cancer (p<0.001). CONCLUSIONS: Women play an important role in health-related matters in the home. Educating women on prostate cancer may improve early detection efforts and reduce the devastating impact of this disease on their family. 相似文献
8.
Two types of phantoms were developed with which to evaluate the overall performance of digital subtraction angiography (DSA) systems. A dynamic phantom, called a "fish bone" phantom, consists of polyethylene tubes that simulate blood vessels with various lesions, such as stenoses, ulcers, and aneurysms. With this phantom, washout curves were obtained representing the relationship between iodine content and time. It will be useful for qualitative assessment of DSA images, evaluation of different image-processing schemes, and studies of blood flow analysis. A static phantom, called a "C-D" phantom, can be used for measurement of quantitative contrast-detail (C-D) diagrams and for daily monitoring of DSA systems. This was constructed of tubes of seven different diameters (2.15-0.28 mm) and 14 different concentrations of contrast medium (100%-1.1% Renografin-76 [meglumine and sodium diatrizoate]). The C-D diagrams were determined from an observer performance study using C-D phantom images obtained at four different DSA settings. 相似文献
9.
It has been argued that the anticipation of ethanol consumption can activate reinforcement substrates involved in alcohol-seeking behavior. To test this hypothesis nucleus accumbens (NAc) dopamine (DA) efflux was monitored in alcohol-preferring (P) and Wistar rats. Rats from each line were divided into two groups: one trained to self-administer 0.05% saccharin and the other trained to self-administer 10% (w/v) ethanol. On the test day dopamine efflux was monitored in all animals during saccharin self-administration. In ethanol-expecting P rats, self-administration of saccharin produced a significant elevation in extracellular DA (150% of baseline within the first 15-20min). In contrast, a significant increase in extracellular DA was only observed during the final 30min of the test session in ethanol-expecting Wistar rats self-administering saccharin. The self-administration of saccharin in animals expecting the sweetener failed to elevate extracellular DA in both strains. Overall, these results suggest that the mere expectation of ethanol availability enhances the efflux of DA in the NAc of the P, but not the Wistar rat, which may play a role in the initiation or maintenance of ethanol seeking behavior in the P line. 相似文献
10.
This follow-up study was undertaken in an effort to ascertain the morbidity in the survivors of infants ≤2000 g birthweight cared for in the two Rockhampton intensive care nurseries.
The records of all infants ≤2000 g delivered in or transferred to Rockhampton during the 11 year period 1979 through 1989 inclusive were extracted. Efforts were made to contact and examine all of these children. Those found to be disabled were assessed as being mildly, moderately or severely affected.
Of the 482 infants of birthweight ≤2000 g treated in the period under review, 393 survived to be discharged from hospital. Eight were known to have died subsequently. Of the remaining 385 children, 288 (74.8%) were able to be contacted and their health status determined. A total of 36 infants were found to have significant disabilities. Twenty-four were mildly affected, five moderately and seven severely affected. Severe disability in infants of ≤1000 g was 16% (3/19).
The incidence of disability was established in 74.8% of the surviving population, It was not dissimilar to the incidence of disability in similar birthweight groups in some Australian tertiary centres for the years under study. It is emphasized that the follow-up was incomplete and recognized that the survival rates and incidence of disability in survivors has improved in tertiary centres since the time frame of this study. 相似文献
Methodology:
The records of all infants ≤2000 g delivered in or transferred to Rockhampton during the 11 year period 1979 through 1989 inclusive were extracted. Efforts were made to contact and examine all of these children. Those found to be disabled were assessed as being mildly, moderately or severely affected.
Results:
Of the 482 infants of birthweight ≤2000 g treated in the period under review, 393 survived to be discharged from hospital. Eight were known to have died subsequently. Of the remaining 385 children, 288 (74.8%) were able to be contacted and their health status determined. A total of 36 infants were found to have significant disabilities. Twenty-four were mildly affected, five moderately and seven severely affected. Severe disability in infants of ≤1000 g was 16% (3/19).
Conclusions:
The incidence of disability was established in 74.8% of the surviving population, It was not dissimilar to the incidence of disability in similar birthweight groups in some Australian tertiary centres for the years under study. It is emphasized that the follow-up was incomplete and recognized that the survival rates and incidence of disability in survivors has improved in tertiary centres since the time frame of this study. 相似文献