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71.
OBJECTIVE: One of the complications of CPB is the systemic inflammatory response syndrome (SIRS). Recent developments tend to minimize the biological impact of CPB in using miniaturized closed circuit with reduced priming volume and less blood-air interface. The benefit of these miniaturized closed circuits in terms of inflammatory response has been proved in coronary surgery. However, in open heart surgery, the CPB circuit is no more closed and the benefit of the miniaturized set-up could disappear. The aim of the study is to compare the SIRS between standard and miniaturized circuits in aortic surgery. METHODS: Forty patients who underwent singular aortic valve replacement were randomly assigned either to a standard CPB (group A, n=20) or to a miniaturized CPB (group B, n=20). Pertinent clinical and surgical data were collected. Hematological parameters (leukocyte and neutrophil counts) and biochemical parameters (C-reactive protein, cytokine tests) were determined pre-, on and post-CPB. RESULTS: There were an increase in leukocyte and neutrophil counts and a decline in hematocrit in both groups. In both groups, there was a raise after CPB, in C-reactive protein, IL-6, TNF-alpha, neutrophil elastase, and IL-10. However, the raises of elastase and TNF-alpha were significantly lower after the weaning of miniaturized CPB (116+/-46 ng/ml and 10+/-4 pg/ml, respectively) compared to standard CPB (265+/-120 ng/ml, P=0.01 and 18+/-7 pg/ml, P=0.03). The raise of IL-10 is also lower with miniaturized circuit (15+/-6 pg/ml) compared to standard circuit (51+/-26, P=0.004). CONCLUSIONS: This study demonstrates in aortic surgery, the lesser inflammatory response of a miniaturized CPB compared to a standard CPB. However, there is always some inflammation after CPB and a small bio-reactive free perfusion circuit is still to be found in open heart surgery.  相似文献   
72.
The state of “nodding off” which the psychoanalyst may experience during therapy is a phenomenon that requires further investigation into its nature, causes, and effects. Even if it occurs only sporadically and is a physiological necessity, it nevertheless has a certain effect and can present certain advantages. This introduction of resistance in the form of sleep can sometimes provide an opportunity in the development of sensorimotor functions for the patient to verbalize his experience, and in any case this phenomenon should not be taken lightly. Recourse to current knowledge regarding sleep can improve our understanding of this phenomenon, and we should be prepared to take the risk of examining psychoanalysis on the basis of a non-analytical approach, i.e. primarily psychobiological and cognitive. This also permits a link to be made between the psychoanalyst’s therapeutic activity and the contextual phenomena which influence cerebral activity and its level of vigilance which is expressed by specific types of verbalization. The pertinence of this risk-taking should also be examined, and a distinction made between physiologically necessary somnolence and other causes. It appears that in the present context, the induction of a state of somnolence is caused by the narcissistic characteristics of a transferential relation that is in the process of development; that is to say, the “positive aspects’’ of narcissism, which are an integral part of psychic growth. However, we should also bear in mind that these narcissistic characteristics can also be expressed in the form of resistance.  相似文献   
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76.
This prospective study was designed to determine the frequency and natural history of hydroureteronephrosis (HUN) after placement of an aortobifemoral vascular graft. A total of 30 patients were evaluated by the study protocol, which included: pre and postoperative biological kidney function tests, preoperative and early postoperative (14th day) intravenous pyelograms and a late (mean 18th month) urologic examination by renal ultrasonic tomography. Four asymptomatic, early cases of HUN were observed in the 57 ureters examined (7%); all four complications regressed in less than 30 days. No cases of symptomatic early or late HUN were observed in this series. Asymptomatic early HUN was a frequent complication in our series (7%) but its benign course does not justify systematic screening. These asymptomatic complications contrast with the symptomatic cases of early or late HUN reported in the literature which necessitated urologic and vascular investigations.  相似文献   
77.
Background: During labor, ephedrine is widely used to prevent or to treat maternal arterial hypotension and restore uterine perfusion pressure to avoid intrapartum fetal asphyxia. However, the effects of ephedrine on uterine blood flow have not been studied during uterine contractions. The purpose of the study was to assess the effects of ephedrine on uterine artery velocities and resistance index using the Doppler technique during the active phase of labor.

Methods: Ten normotensive, healthy parturients with uncomplicated pregnancies at term received intravenous ephedrine during labor to increase mean arterial pressure up to a maximum of 20% above their baseline pressure. Peak systolic and end-diastolic Doppler flow velocities and resistance indices were measured in the uterine artery before and immediately after administration of bolus intravenous ephedrine and after ephedrine washout. Umbilical and fetal middle cerebral arterial resistance indices and fetal heart rate were also calculated.

Results: After ephedrine administration, mean arterial pressure increased by 17 +/- 4%. End-diastolic flow velocity in the uterine artery at peak amplitude of uterine contraction was restored to 74% of the value observed in the absence of contraction. The systolic velocity was totally restored, and the uterine resistance index was significantly decreased, compared with the values in the absence of contraction. Between uterine contractions, ephedrine induced similar but less marked effects. Fetal hemodynamic parameters were not altered by ephedrine administration.  相似文献   

78.
四种口服头孢菌素的体外抗菌活性的比较研究   总被引:2,自引:0,他引:2  
本文报道口服Cefixime对900株需氧菌和厌氧菌的体外抗菌作用,并与其它口服的头孢克罗、头孢羟氨苄和头孢氨苄进行了比较。Cefixime对链球菌具较强作用,但对葡萄球菌的作用较差;对肠球菌无效。对肠杆菌科细菌的抗菌活性四者之中以Cefixime最强。Cefixime对头孢氨苄耐药株仍具高度活性,其MIC均值可降低60~1200倍以上。绿脓杆菌、硝酸盐阴性杆菌、鲁氏不动杆菌和产碱杆菌对Cefixime和其它3种头孢菌素的敏感性均较差。四者对厌氧菌的作用除厌氧球菌外其抗菌活性都很弱。Cefixime对β-内酰胺酶稳定,口服吸收良好,抗菌作用强,是一个值得进行临床研究的口服头孢菌素。  相似文献   
79.
Levels of the c-fos protein were assayed in mouse cerebellar granule cells during their in vitro development under different culture conditions. When grown in media favoring both their survival and differentiation, i.e. in the presence of 30 mM K+ or 12.5 mM K+ plus 100 microM N-methyl-D-aspartate (NMDA), the c-fos protein becomes detectable in the nucleus of granule cells on and after 6 days and persists to high levels until the culture begins to decline. The protein c-fos appears therefore after the critical period described for the survival effect of K+ depolarization or NMDA receptor stimulation which corresponds to days 2-5 after plating. The c-fos protein remains however scarcely detectable or undetectable throughout the life-span of cells cultured under conditions providing poor survival and differentiation, i.e. in the presence of low K+ (5 or 12.5 mM) alone or when the effect of NMDA is blocked by the NMDA receptor antagonist MK-801. Interestingly, in cortical and striatal neurons, the survival and differentiation of which being not affected by depolarizing media, no c-fos protein is detected whatever the culture conditions tested at least during the first 18 days in vitro. This suggests that long-term expression of the c-fos gene might be related to some aspect of the late in vitro differentiation process of cerebellar granule cells.  相似文献   
80.
During 1989, 316 members of a cohort of homosexual men were tested for HIV-specific DNA by the polymerase chain reaction (PCR) using a pair of gag-region primers. Of 125 HIV-seronegative subjects, 123 (98.4%) were PCR-negative while 158 (82.7%) of 191 HIV-seropositive subjects were PCR-positive. Fewer of the 33 subjects who were seropositive and PCR-negative were at Centers for Disease Control (CDC) stage IV than the seropositive, PCR-positive subjects (6 versus 25%; P = 0.030). The seropositive, PCR-negative group had higher mean CD4 counts (640 versus 490 x 10(6) cells/l; P = 0.006), higher CD4: CD8 ratios (0.92 versus 0.64; P = 0.004), lower immunoglobulin (Ig) G levels (1290 versus 1645 mg/dl; P = 0.002), lower IgA levels (168 versus 251 mg/dl; P less than 0.001), and lower C1q binding activity (8 versus 14%; P = 0.010) than the seropositive, PCR-positive subjects. The median rate of CD4 cell decline in the 3 years preceding the PCR sample was less marked in the seropositive, PCR-negative group than the seropositive, PCR-positive group (-58 versus -77 x 10(6) cells/l per year; P = 0.028). To control for duration of infection, we restricted the analysis to the subgroups of 11 seropositive, PCR-negative subjects and 34 seropositive, PCR-positive subjects who had seroconverted earlier in the cohort study. Both subgroups had similar durations of infection, yet the same pattern of differences persisted.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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