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41.
The risk of cholecystectomy for acute cholecystitis in diabetic patients.   总被引:5,自引:0,他引:5  
In order to evaluate the risk of acute cholecystitis in diabetic patients, we analyzed 2,700 consecutive cholecystectomies, 566 of which were performed in the presence of acute cholecystitis. Of these patients 123 had diabetes mellitus (DM) and 433 had no diabetes (ND). The aim of this study was to establish the comparative risks in the two groups. We found that diabetics are more likely to be operated on in the acute stage of their disease (22% vs. 12%). The DM group had a higher rate of septic bile, gangrenous changes and perforations of the gallbladder wall. The morbidity rate was higher in the DM group (21% vs. 9%), and mortality was slightly higher in the DM group. The degree of additional operative risk does not in our view justify recommending cholecystectomy in diabetic patients with asymptomatic gallstones. Early surgery however, is highly recommended in diabetics with symptomatic gallstones and acute cholecystitis.  相似文献   
42.
43.
Women with polycystic ovary syndrome (PCOS) undergoing ovulation induction appear to be extremely sensitive to gonadotropin stimulation and at increased risk for ovarian hyperstimulation syndrome. To determine granulosa cell responsiveness to recombinant human FSH (r-hFSH), dose-response studies were conducted in 16 individual PCOS patients and 7 normal women. Each subject received an iv injection of r-hFSH at doses of 0, 37.5, 75, or 150 IU in a randomized fashion on four separate occasions. Blood samples were obtained at frequent intervals before and for 24 h after r-hFSH administration for measurement of gonadotropins and steroid hormones. Our results showed that administration of r-hFSH produced instantaneous and equivalent dose-related increases in serum FSH in PCOS and normal women, which were followed by similar exponential decreases to baseline levels within 24 h in both groups. In PCOS subjects, the peak mean incremental response of serum estradiol (E(2)) to 150 IU of r-hFSH was 1.8-fold greater (P < 0.0001) and considerably accelerated compared with that found in normal women. In contrast, E(2) responses to 37.5 IU and 75 IU were similar between groups. Regression analysis of maximal E(2) concentrations in response to r-hFSH in each individual subject revealed that the slope of the linear trend line in the group of women with PCOS (r = 0.82) was significantly greater (P < 0.01) than that of normal controls (r = 0.71). The time-course of response revealed that in PCOS women, increases of E(2) were not sustained, compared with those of normal controls, because peak concentrations were followed by an estimated 40% decrement in circulating levels, whereas E(2) levels in normal women persisted for 24 h after reaching maximal values. These findings indicate that women with PCOS exhibit a significantly greater capacity for E(2) production in response to iv r-hFSH, compared with normal women. In PCOS, E(2) production was relatively transient because after peak concentrations a marked decline was detected at each dose, unlike normal women who exhibited persistent elevations of E(2) for up to 24 h. That this distinction was dose-dependent supports the concept of an FSH dose-response threshold, beyond which PCOS but not normal women are susceptible to ovarian hyperresponsiveness.  相似文献   
44.
Left ventricular assist devices (LVADs) have proven successful as bridge to transplant devices for patients awaiting donor organs. While survival rates continue to increase, destination therapy remains hindered by thrombus formation within the device. Research has shown that thrombosis is correlated to the fluid dynamics within the device and may be a result of sustained shear rates below 500?s?1 on the polyurethane blood sac used in the Penn State pulsatile LVAD. Particle image velocimetry is used to compare flow within two 50?cc LVAD designs to assess fluid patterns and quantify wall shear rates in regions known from in vivo studies to be susceptible to thrombus formation. The two designs differ in their front face geometry. The V-1 model has an outward-facing ??dome?? whereas the face of the V-2 model is flat. A thrombus susceptibility metric, which uses measured wall shear rates and exposure times, was applied to objectively compare pump designs over the entire cardiac cycle. For each design, there are regions where wall shear rates remained below 500?s?1 for the entire cardiac cycle resulting in high thrombus susceptibility potential. Results of this study indicate that the V-2 device had an overall lower propensity for thrombus formation in the current region of interest.  相似文献   
45.
46.
Coenzyme Q10 (CoQ10) is synthesized by the human body and found in certain foods. Daily supplementation of CoQ10 could protect against heart disease but the bioavailability of CoQ10 supplements depends on the formulation taken. We compared the bioavailability and antioxidant properties of two commercial CoQ10 formulations, a commercial grade CoQ10 powder (commercial grade CoQ) and a new BT-CoQ10 BIO-TRANSFORMED (BT-CoQ10) obtained by fermentation of a soy-based, CoQ10-rich media with baker's yeast. Eleven healthy individuals participated in a randomized two-way crossover trial, with a 3-week washout period. Capsules containing 300 mg of either BT-CoQ10 or commercial grade CoQ10 were given daily for 1 week and multiple blood samples were taken for CoQ10, glutathione and glutathione peroxidase (GPx) determination. In 3 subjects, baseline plasma CoQ10 levels were lower prior to BT than prior to commercial grade CoQ treatment. In the remaining participants, ingestion of BT vs. commercial grade CoQ significantly increased maximum plasma CoQ10 concentration (+126%, p = 0.04) and tended to increase CoQ10 area under the curve from 0 to 24 h (+160%, p = 0.07). One week of treatment with each formulation increased plasma CoQ10 but did not alter plasma glutathione or GPx activity. The enhanced bioavailability of the BT product might be due to its predominantly reduced, hydrophilic membrane-complex form.  相似文献   
47.
48.

OBJECTIVES:

Nasal continuous positive airway pressure is used as a standard of care after extubation in very-low-birth-weight infants. A pressure of 5 cmH2O is usually applied regardless of individual differences in lung compliance. Current methods for evaluation of lung compliance and air distribution in the lungs are thus imprecise for preterm infants. This study used electrical impedance tomography to determine the feasibility of evaluating the positive end-expiratory pressure level associated with a more homogeneous air distribution within the lungs before extubation.

METHODS:

Ventilation homogeneity was defined by electrical impedance tomography as the ratio of ventilation between dependent and non-dependent lung areas. The best ventilation homogeneity was achieved when this ratio was equal to 1. Just before extubation, decremental expiratory pressure levels were applied (8, 7, 6 and 5 cmH20; 3 minutes each step), and the pressure that determined the best ventilation homogeneity was defined as the best positive end-expiratory pressure.

RESULTS:

The best positive end-expiratory pressure value was 6.3±1.1 cmH20, and the mean continuous positive airway pressure applied after extubation was 5.2±0.4 cmH20 (p = 0.002). The extubation failure rate was 21.4%. X-Ray and blood gases after extubation were also checked.

CONCLUSION:

This study demonstrates that electrical impedance tomography can be safely and successfully used in patients ready for extubation to suggest the best ventilation homogeneity, which is influenced by the level of expiratory pressure applied. In this feasibility study, the best lung compliance was found with pressure levels higher than the continuous positive airway pressure levels that are usually applied for routine extubation.  相似文献   
49.
50.
Control Analysis     
In this paper I present three collections of a patient's words and phrases that I arranged in a particular form. I discuss how I arranged the words in this way as I was struggling to get a sense of what felt “emotionally true” in my work with this patient and how this process helped me to grasp her use of dissociation. I draw on Gergen's work for a cultural perspective on dissociation, on Winnicott's concept of psychesoma dissociation, and on Goldberg's additions to Winnicott's theory. I show how the use of omnipotent, narcissistic structures may mask the use of dissociation (by patient and analyst) and make it quite an elusive phenomenon. My focus is on the process I went through, clinically and in my thinking and writing, as I discovered my own and my patient's dissociated use of mind and emotion and grappled with how to find a reassociation between these psychic functions and their somatic base.  相似文献   
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