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101.
胸腺瘤临床病理的预后因素研究   总被引:8,自引:2,他引:6  
目的 探讨胸腺瘤临床病理特点与预后的关系。方法 对130例胸腺瘤的重症肌无力、肿瘤大小、坏死、核分裂及包膜情况、组织学分型(按照L-B分类及M-H分类)、Massaoka临床分期等诸多因素进行分析,观察其5,10年生存率的差别,所得数据进行统计学U检验及χ^2检验。结果 重症肌无力的有无、肿瘤大小、坏死、核分裂及L-B分类均与预后无关(P>0.05);而肿瘤有无包膜、M-H分类及临床分期与生存率有明显相关性。有包膜者5,10年生存率分别为100%和93.1%,无包膜者分别为54.4%和40.0%(P<0.05)。按M-H分类,髓质型5,10年生存生存率分别为100%和79.8%,混合型分别为97.5%和88.4%,皮质为主型分别为83.3%和50.1%,皮质型分别为60.2%和29.9%,分化好的胸腺癌(WDTC)分别为43.4%和0%(P<0.05)。临床分期中Ⅰ期5,10年生存率分别为100%和93.2%,Ⅱ期分别为84.6%和78.4%,Ⅲ期分别为45.3%和19.8%,Ⅳ期分别为38.0%和0(P<0.01)。其中以细胞的异型性及有无侵犯胸腺周围器官对预后尤为重要。结论 L-B分类与预后无关;M-H分类、临床分期与预后有关,尤其是瘤细胞呈多角形和大圆形、临床侵犯胸腺外器官者对预后影响较明显。  相似文献   
102.
Toxicities of high-dose conditioning regimens have limited the use of conventional unrelated donor hematopoietic cell transplantation (HCT) to younger, medically fit patients. Based on preclinical studies, an HCT approach has been developed for elderly or medically infirm patients with HLA-matched or mismatched unrelated donors. In this study, 52 patients with hematological diseases were included. Most (88%) had preceding unsuccessful conventional HCT or refractory/advanced disease. Patients were treated with fludarabine 30 mg/m(2)/d from days -4 to -2, 2 Gy total body irradiation on day 0, cyclosporine at 6.25 mg/kg twice daily from day -3, and mycophenolate mofetil at 15 mg/kg twice daily from day 0. Durable donor chimerism was attained in 88% of the patients. By day 28, a median of 100% of CD56(+) cells were of donor origin. Granulocyte and T-cell donor chimerism increased to medians of 100% on day 56 and day 180 (range, 55%-100%), respectively. Acute GVHD, grade II, was seen in 42% (CI, 29%-56%); grade III in 8% (CI, 0%-15%); and grade IV in 13% (CI, 4%-23%) of patients; it was fatal in 9%. The 100-day transplantation-related mortality was 11%. Complete remissions, including molecular remissions, were seen in 45% of patients with measurable disease before transplantation. Mortality from disease progression was 27% at one year. With a median follow-up of 19 months, 18 of the 52 patients (35%) were alive and 25% were in remission. HCT from HLA-matched or mismatched unrelated donors can be performed with a reduced intensity conditioning regimen in patients ineligible for conventional HCT.  相似文献   
103.
A comparison of fentanyl-O2 and sufentanil-O2 for cardiac anesthesia   总被引:3,自引:0,他引:3  
In a prospective randomized study of 48 patients scheduled to undergo elective coronary artery surgery, sufentanil (20 micrograms/kg) was compared with fentanyl (100 micrograms/kg) anesthesia by assessing hemodynamic and plasma catecholamine level responses to surgery. At 15 points during the study, cardiovascular dynamics were recorded. At six points in the study, arterial blood was obtained for simultaneous assays of plasma concentrations of epinephrine, norepinephrine, and dopamine. Neither mean cardiovascular dynamics nor catecholamine concentrations were statistically significantly different between the groups preoperatively. Both agents provided generally stable hemodynamics during surgery. Sufentanil was associated with decreased systemic vascular resistance at several time points with concurrent increased cardiac index and heart rate. Although catecholamine levels increased somewhat during cardiopulmonary bypass in both groups, there were no significant differences between the groups at any point except that at chest closure patients given sufentanil had significantly lower dopamine concentrations than those given fentanyl. Times for recovery from surgery failed to show any difference between the two groups of patients. Blood pressure increases with patients given sufentanil compared favorably with those given fentanyl. We conclude that at these doses, with this surgery, there were no major clinical differences, though sufentanil produced significantly lower systemic vascular resistance at several events and had a lower plasma dopamine concentration after cardiopulmonary bypass.  相似文献   
104.
Counting reticulocytes by flow cytometry: use of thiazole orange   总被引:1,自引:0,他引:1  
Thiazole orange is a new fluorescent dye which will bind to the residual RNA in the cytoplasm of reticulocytes and allow their enumeration by FACS analysis. We have evaluated the use of this dye in the routine haematology laboratory. There is an excellent correlation between manual and FACS reticulocyte counts (r = 0.98) but FACS counting showed significantly higher precision (CV = 3.1) than the manual method (CV = 11.9) for single observer, 20.8% for multiple observers). Clinical specimens showed stable reticulocyte counts for 6 h if stored at 4 degrees C allowing efficient batching of samples. There was a significant fall in reticulocyte counts stored for 24 h at both 4 degrees C and 21 degrees C. Evaluation of 78 male and 76 female blood donors by FACS analysis gave normal ranges (mean % +/- 2 SD) of 0.74 +/- 0.48 and 0.84 +/- 0.56 respectively (P less than 0.005). When corrected to absolute values there was no sex difference (36 +/- 24 x 10(9)/l). Thiazole orange is an effective stain for the automated counting of reticulocytes by FACS analysis.  相似文献   
105.
We attempted to evaluate the role of maternal hyperphenylalaninaemia (HPA) as an isolated cause of mental retardation and microcephaly in children. This transversal study observed the plasma phenylalanine from mothers of 161 children with mental retardation and/or microcephaly of unknown origin. In this sample, we found two women with previously undiagnosed HPA, a frequency (2/161) higher than expected for our general population (1:12 500) ( p < 0.001). We concluded that the plasma phenylalanine levels should be determined during preconceptional evaluation of every woman of reproductive age that already has had a child affected either by mental retardation or microcephaly of unknown cause. It is particularly significant where women currently having their pregnancies have not been screened for phenylketonuria as newborns, as happens in most developing countries.  相似文献   
106.
Apneic, anesthetized patients frequently develop airway obstruction or may be disconnected from ventilatory support. The rate of PaCO2 rise is usually assumed to be equal to that of anesthetized humans who are receiving apneic oxygenation. Apneic oxygenation may eliminate CO2 because it requires a continuous O2 flow. The CO2 rate of rise in anesthetized humans with airway obstruction was measured. Fourteen consenting healthy adults were monitored continuously with pulse oximetry and EKG. Enflurane--O2 anesthesia was established for at least 10 minutes with normal PaCO2 without neuromuscular blockade so that anesthesia was deep enough to prevent spontaneous ventilation. Then, patients' tracheal tubes were clamped. Arterial blood samples were obtained before and after 0, 20, 40, 60, 120, 180, 240, and 300 seconds after clamping, provided that oxyhemoglobin saturation exceeded 0.92. The equation that best described the PaCO2 rise was a logarithmic function. Piecewise linear approximation yielded a PaCO2 increase of 12 mmHg during the first minute of apnea, and 3.4 mmHg/minute thereafter. These values should be employed when estimating the duration of apnea from PaCO2 change for anesthetized patients who lack ventilatory support. In addition, it appears that the flows of O2 that most earlier investigators used when delivering apneic oxygenation probably did not eliminate significant CO2 quantities.  相似文献   
107.
108.
An analysis of patient records in four different DRG categories estimated direct nursing care requirements. The evaluation of these results showed a great range in direct hours of nursing care, as well as resultant cost of nursing care within and among the DRG categories. Nursing resource use is widely fluctuating based on acuity levels, length of stay, and DRG category. Thus, it was concluded the variables inherent in a model to predict cost rely on determinants of the functional needs of the individual patient.  相似文献   
109.
It has been proposed that extremely low frequency (ELF) magnetic fields may enhance tumorigenesis through a co-promotional mechanism. This hypothesis has been further tested using the two-stage model of mouse skin carcinogenesis, i.e. 12-O-tetradecanoylphorbol-13-acetate (TPA)- induced promotion of skin tumors in mice initiated by a single subcarcinogenic dose of 7,12-dimethylbenz[a]anthracene. Experimentation described herein utilized the SENCAR mouse and examined the effect of a magnetic field on skin tumor promotion induced by three different doses of TPA within its dose-response range, i.e. 0.85, 1.70 or 3.40 nmol, administered twice per week. SENCAR mice (56/treatment group) were exposed to a 60 Hz magnetic field having a flux density of 2 mT for 6 h/day for 5 days/week and compared with mice exposed to the ambient magnetic field. Tumor incidence and multiplicity were monitored weekly for 23 weeks of TPA promotion. Statistical evaluation of the effects of the magnetic field on tumor incidence and multiplicity did not reveal any statistically significant effects; thus, within the sensitivity limits imposed by the animal model and the exposure parameters employed, no promotional or co-promotional effect of a 2 mT magnetic field on skin tumor development in SENCAR mice could be demonstrated.   相似文献   
110.
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