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991.
王戬 《中华现代医院管理杂志》2006,4(6):27-30
本文对现有的以医生工作站为中心的门诊系统进行分析研究后,针对目前存在的一些问题提出了改进方法,通过利用第二代身份证录入信息,建立门诊预交金账户,优化就诊过程等方法,设计了一个以病人为中心的门诊信息系统。给患者提供一种清晰快捷的就医环境,提高了医院的服务质量和工作效率。 相似文献
992.
We have previously demonstrated the expression of large-conductance, calcium-activated potassium (BK) channels in human glioma cells. In the present study, we characterized the calcium sensitivity of glioma BK channels in excised membrane patches. Channels in inside-out patches were activated at -60 mV by 2.1 x 10(-6) M cytosolic Ca(2+), were highly K(+)-selective, and had a slope conductance of approximately iqual 210 pS. We characterized the Ca(2+) sensitivity of these channels in detail by isolating BK currents in outside-out patches with different free [Ca(2+)](i). The half-maximal voltage for channel activation, V(0.5), of glioma BK currents in outside-out patches was +138 mV with 0 Ca(2+)/10 EGTA. V(0.5) was shifted to +81 mV and -14 mV with free [Ca(2+)](i) of 1.5 x 10(-7) M and 2.1 x 10(-6) M, respectively. These results suggest that glioma BK channels have a higher Ca(2+) sensitivity than that described in many other human preparations. Data obtained from a cloned BK channel (hbr5) expressed in HEK cells support the conclusion that glioma BK channels have an unusually high sensitivity to calcium. In addition, the sensitivity of glioma BK channels to the BK inhibitor tetrandrine suggests the expression of BK channel auxiliary beta-subunits by glioma cells. Expression of the auxiliary beta-subunit of BK channels by glioma cells may relate to the high Ca(2+) sensitivity of glioma BK channels. 相似文献
993.
Feldman DM Borgida AF Rodis JF Leo MV Campbell WA 《American journal of obstetrics and gynecology》2003,189(3):710-713
OBJECTIVE: The purpose of this study was to compare the efficacy and side effects of two different misoprostol regimens for second-trimester pregnancy termination. STUDY DESIGN: We performed a randomized clinical trial in patients who were at 14 to 23 weeks of gestation and who were admitted for medical termination of pregnancy. All patients received 800 microg of vaginal misoprostol and were assigned randomly to 400 microg of oral misoprostol or 400 microg of vaginal misoprostol every 8 hours. Efficacy and side effects were compared. The mean induction time of the study group was compared with that of an historic control group that had received 400 microg vaginally every 12 hours. RESULTS: Forty-three women were assigned randomly, 22 women to vaginal misoprostol and 21 women to oral misoprostol. Induction time and hospital stay were slightly shorter for the oral group; however, the differences were not significant. Side effects were similar for both groups. CONCLUSION: After an initial 800 microg dose of vaginal misoprostol, a regimen of 400 microg of oral misoprostol every 8 hours is as effective as the same dose of vaginal misoprostol with no additional side effects, which provides a convenient alternative for midtrimester pregnancy termination. 相似文献
994.
Physical Stability of Proteins in Aqueous Solution: Mechanism and Driving Forces in Nonnative Protein Aggregation 总被引:5,自引:0,他引:5
Irreversible protein aggregation is problematic in the biotechnology industry, where aggregation is encountered throughout the lifetime of a therapeutic protein, including during refolding, purification, sterilization, shipping, and storage processes. The purpose of the current review is to provide a fundamental understanding of the mechanisms by which proteins aggregate and by which varying solution conditions, such as temperature, pH, salt type, salt concentration, cosolutes, preservatives, and surfactants, affect this process. 相似文献
995.
Rubino C Adjadj E Guérin S Guibout C Shamsaldin A Dondon MG Valteau-Couanet D Hartmann O Hawkins M de Vathaire F 《International journal of cancer. Journal international du cancer》2003,107(5):791-796
The aim of our study was to quantify the risk of second malignant neoplasms (SMNs) among long-term survivors of neuroblastoma and to study the influence of treatment on this risk. We studied data from 544 5-year survival patients diagnosed with neuroblastoma before age 16 years at 8 French and British treatment centres from 1948 to 1986. After an average follow-up of 15 years (range, 5-38 years), 12 children developed a total of 13 SMNs, whereas 1.19 were expected from general population rates. Among these SMNs, there were 5 thyroid and 3 breast cancers. Increases of the risks of SMN were observed with time since neuroblastoma diagnosis and attained age. In a multivariate analysis, the relative risk of SMN associated with radiotherapy was 4.3 (95% CI 0.8-78), whereas no increased risk of SMN was associated with the administration of chemotherapy as a whole (RR = 0.4, 95% CI 0.1-1.9). Young children treated for a neuroblastoma have significantly increased risks of SMN over 3 decades of follow-up. Radiotherapy treatment was found to be an important risk factor for developing SMNs, whereas no effect of chemotherapy was evidenced. Although our findings reflect the late effects of past therapeutic modalities, they underscore the importance of long-term surveillance of young children treated for a neuroblastoma. For these patients, many more years of follow-up are required to appreciate their overall risks of treatment-related SMNs. 相似文献
996.
Assessment of coronary artery disease with second harmonic myocardial perfusion contrast echocardiography 总被引:2,自引:2,他引:0
Objectives To assess the relationship between myocardial regional perfusion using second harmonic myocardial contrast echocardiography (MCE) by venous injection of Levovist and coronary artery stenosis detected by coronary angiography to determine whether MCE can be used to detect coronary artery disease (CAD) and its sensitivity and specificity for detecting CAD.Methods Thirty-six patients who underwent coronary artery angiography and MCE formed the study groups.Ten myocardial segments (5 each in the apical two- and four-chamber views) from the images were scored for detecting myocardial perfusion as follows: 1, normal perfusion; 2, decreased perfusion; and 3, perfusion defect.The arteries were classified as normal or diseased.The diseased arteries were classified into three groups according to the perfusion scores.Results There were significant differences in coronary diameter stenosis among the different perfusion score groups (P<0.001).There were 10 total occluded arteries, and the myocardial perfusion scores were different because of different collateral circulation.In the normal perfusion group (Group A), the coronary diameter stenosis was 65%±12%, and the myocardial perfusion score index was 1±0.00.In the decreased perfusion group (Group B), the average coronary diameter stenosis was 82%±8%, and the myocardial perfusion score was 1.93±0.16.The diameter stenosis was less than 85% in 63 % of the coronary arteries (including diameter stenosis ≤75% in 12% of the vessels).The diameter stenosis was 85%-90% in 22% of the coronary arteries and >90% in 15% of the arteries.In the perfusion defect group (Group C), the average diameter stenosis was 90%±6%, and the myocardial perfusion score index was 2.89±0.24.The diameter stenosis was ≥85% in 94% of the coronary arteries, and the diameter stenosis was <85% and >75% only in 6% of the coronary arteries.The overall sensitivity and specificity of MCE in identifying angiographic coronary diameter stenosis was 67% and 100%, respectively.The false negative rate was 32.6% for the 108 coronary arteries.Further subdivided analysis showed the sensitivities in Groups A, B and C were 0, 100%, and 100%, respectively.The sensitivity increased with increased lumen diameter stenosis of coronary arteries.Conclusions There is a close relationship between coronary artery stenosis and MCE perfusion scores.MCE with venous injection of new generation contrast can define the presence of CAD and lesion graded classifications.Some disagreements between perfusion score and coronary diameter of stenosis may indicate other factors such as different collateral circulation, which should be further investigated.As artery stenosis increases, the sensitivity of MCE is increased. 相似文献
997.
Stimulation of L-type Ca(2+) channels by increase of intracellular InsP3 in rat retinal pigment epithelial cells 总被引:4,自引:0,他引:4
The purpose of this study was to investigate the role of voltage-dependent L-type Ca(2+)channels in intracellular Ca(2+)signaling of the retinal pigment epithelium (RPE). Patch-clamp techniques in conjunction with measurements of the intracellular free Ca(2+)using the Ca(2+)-sensitive fluorescence dye fura-2 were performed using cultured rat RPE cells. Intracellular application of inositol-1,4,5-trisphosphate (InsP3; 10 microM) via the patch-pipette during the whole-cell configuration led to an increase in the intracellular free Ca(2+)([Ca(2+)](i)). This effect could be reduced by the L-type Ca(2+)channel blocker nifedipine (2 microM). At the moment of the maximal rise in [Ca(2+)](i)L-type currents displayed an increase in the current density and shifts in the activation curve and of the steady-state inactivation. Comparable changes of L-type channel activity could be observed by induction of capacitative Ca(2+)entry, a maneuver to release Ca(2+)from intracellular Ca(2+)stores independently from InsP3. The increase in L-type Ca(2+)channel activity and [Ca(2+)](i)by intracellular application of InsP3 or induction of capacitative Ca(2+)entry could be inhibited by blocking tyrosine kinase activity using genistein (5 microM) or tyrphostin 51 (10 microM). It is concluded that L-type Ca(2+)channels are involved in the Ca(2+)/InsP3 second messenger system by generating an influx of extracellular Ca(2+)into the cell. This is enabled by depletion of cytosolic Ca(2+)stores and tyrosine kinase-dependent activation of L-type channels. 相似文献
998.
Between 1976 and 1996, 176 borderline ovarian tumours were registered in the Cancer Registry of the Swiss canton of Vaud, corresponding to an age-adjusted incidence (world standard) of 2.7 in 100,000. Incidence rose from 1.7 per 100,000 during 1976-81 to 2.7 per 100,000 during 1987-91, and then levelled off; 58% of cases were serous and 41% mucinous. Relative survival was 94% at 10 years; 18 second neoplasms were observed, compared with 10.3 expected, and there was a significant excess of invasive ovarian cancers (four observed, including three synchronous, compared with 0.4 expected). 相似文献
999.
Marc Van Den Bergh Evelyne Bertrand Yvon Englert 《Journal of assisted reproduction and genetics》1995,12(4):258-262
Objective
Our objective was to evaluate the time course and the predictive value of the extrusion of the second polar body after intracytoplasmic injection (ICSI) related to the fertilization rate, embryo cleavage and quality.Setting
The setting was the in vitro fertilization program of a university hospital.Patients
Twenty-one patients were treated with intracytoplasmic single sperm injection either for fertilization failure in IVF, low fertilization in IVF (<5%), or severe male factors.Design
One hundred thirty-five of 205 metaphase 2 oocytes treated with intracytoplasmic single sperm injection were observed 1, 2, and 3 hr after the assisted fertilization procedure. Extrusion of the second polar body was recorded. For each of these oocytes, fertilization was noted 18 hr after ICSI and cleavage and embryo quality were assessed 24 hr later. The 70 remaining oocytes were used to assess a possible negative effect of repeated exposure to light microscopy.Results
The extrusion of the second polar body 3 hr after injection was an observation with a sensitivity of 0.87, a specificity of 0.58, and a high positive predictive value (0.90) toward oocyte fertilization. Twenty-nine and four-tenths percent of the oocytes extruded a second polar body within the first hour, 56.6% within the first 2 hr, and 78.3% had a second polar body 3 hr after injection. This time course was related neither to the speed of embryo cleavage nor to the embryo quality. Fertilization, cleavage, and embryo quality were not affected by repeated observation as deduced from comparison with the control group and confirmed by a high pregnancy (62% per oocyte retrieval) and implantation rate (22% per replaced embryo).Conclusion
Oocytes can be checked, in all safety, 3 hr after a single sperm injection for the presence of a second polar to predict oocyte fertilization with a high certainty. 相似文献
1000.
The case presented is of a 7-year-old girl who developed acute lymphoblastic leukaemia (ALL) with t(4; 11)(q21; q23) 5 years after the onset of neuroblastoma and 4 months after completing treatment for a first relapse. Consideration is given to the relative importance in this case of genetic factors and chemotherapeutic drugs in the etiology of ALL. 相似文献