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Smith  R; Rosen  JM; Alderson  PO 《Radiology》1986,158(1):63-66
The preoperative cholescintigrams of 16 patients with subacute or chronic gallbladder (GB) perforation demonstrated at surgery were reviewed, and the scintigraphic findings were characterized. Persistent GB nonvisualization was found in each study. Additional findings included a band of increased pericholecystic hepatic activity (PCHA) (n = 7) and/or a photopenic region in the GB fossa (n = 7). PCHA and photopenic region findings, when visualized, were most commonly associated with a subacute localized perforation with pericholecystic abscess formation. However, the sensitivity of each of these findings was only 44%. Cholescintigrams did not directly demonstrate the perforation site in any patient. Although the presence of the PCHA sign and/or GB fossa photopenic region appears to identify a subgroup of patients at increased risk for perforation, cholescintigraphy is relatively insensitive for detection of subacute or chronic GB perforation.  相似文献   
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The stability of betamethasone-17-valerate in semi-solid bases has been investigated. Emphasis has been placed on the stability problems which could arise upon dilution of proprietary preparations by the use of model systems. Betamethasone-17-valerate has been shown to decompose to betamethasone-21-valerate and betamethasone alcohol. Quantitation of the decomposition was by direct densitometry on thin layer chromatographic plates. The decomposition was found to be an apparent first order process and to depend on the diluent used and its concentration. Attempts were also made to relate the rate of decomposition to the pH of the base used, and to stabilize the products.  相似文献   
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Smith  R; Rosen  JM; Gallo  LN; Alderson  PO 《Radiology》1985,156(3):797-800
Gallbladder nonvisualization in cholescintigraphy has been shown to be a reliable finding in acute cholecystitis. In some cholescintigrams, we have observed faintly increased pericholecystic hepatic activity in conjunction with gallbladder nonvisualization. To determine the frequency and significance of the pericholecystic hepatic activity finding, we evaluated 334 consecutive adult patients who had cholescintigrams with technetium-99m diisopropylphenylcarboamoyl iminodiacetic acid. Pericholecystic hepatic activity was seen in 21% of the abnormal scans demonstrating gallbladder nonvisualization but in none of the other scans. Thirteen of these patients underwent surgery; 11 (85%) were found to have acute cholecystitis, and two (15%) had chronic cholecystitis. Four patients (31%) had acute gangrenous cholecystitis, and five (39%) had cholecystitis complicated by gallbladder perforation. The pericholecystic hepatic activity sign is not specific for gangrenous cholecystitis or gallbladder perforation but does reliably indicate inflammatory gallbladder disease and is associated with a relatively high incidence of cholecystitis complicated by perforation.  相似文献   
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心脏自主神经重构与心肌梗死后室性心律失常   总被引:2,自引:0,他引:2  
心肌梗死后心脏不同区域出现不同程度的去迷走神经支配、去交感神经支配以及交感神经过度再生。这种心脏自主神经的不均一重构加重了心肌梗死后心肌的电生理异质性,导致了室性心律失常易感性增加。多种针对自主神经重构的治疗手段可以有效预防及治疗心肌梗死后患者的室性心律失常,具有较大的临床应用前景。  相似文献   
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抽取了北京市丰台区7家民营医院,采用定性访谈和问卷调查方式,分析了民营医院自身的优势、存在的问题以及面临的制约因素,提出了完善职称晋升、医保定点及税收政策,加强与民营医院的沟通,加强对民营医院的监管等措施,为如何更好地引入社会资本提供参考建议。  相似文献   
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Prognostic factors for the success rate of embryo freezing   总被引:5,自引:6,他引:5  
To find some prognostic factors for the outcome of frozen-thawed cycles, we have retrospectively analysed all frozen pre-embryos that were thawed during 1993 and 1994 at two in-vitro fertilization (IVF) units in Sweden. Supernumerary pre-embryos were frozen from 551 oocyte retrievals and these resulted in 660 frozen-thawed cycles which lead to 623 thawed embryo transfers. The outcome of these transfers was 137 clinical pregnancies with a pregnancy rate of 22% per frozen-thawed embryo transfers. Women <40 years of age had a higher birth rate than those > or =40 years, 19 and 5% respectively (P < 0.01). Transfers with two and three pre-embryos resulted in pregnancy rates of 23 and 27%, respectively, compared with 14% for transfer of one embryo. A pregnancy resulting from the initial embryo transfers had a predictive value for results of the subsequent frozen-thawed cycle. Embryo grade and cleavage stage at the time of freezing was important for the survival of the frozen-thawed pre-embryos. The pregnancy rate was not influenced by the cleavage stage, but a tendency toward a lower pregnancy rate was seen for the embryos with lower grading. To conclude, cryopreservation seems to be beneficial in women <40 years of age, who have supernumerary pre-embryos of good quality for freezing and of which at least two can be transferred.   相似文献   
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