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31.
Risk of death from acute pancreatitis   总被引:5,自引:0,他引:5  
Summary Conclusions The analysis of all the data available in 192 patients at 24 h from admission shows that only serum glucose above 250 mg/dL (13.88 mmol/L) and serum creatinine above 2 mg/dL (176.8 μmol/L) are prognostic factors of death (P<0.0001). When, however, pathological chest X-rays are also considered in a subset of 149 patients, these and serum creatinine are prognostic factors of death with odds ratios of 2.9 (95% CL 1.3–6.3) and 9.4 (95% CL 2.2–40.7), respectively (P<0.0001). Background In patients suffering from acute pancreatitis, neither Ranson scores nor Glasgow criteria evaluation at 24 h yield a sufficiently reliable prognosis of the risk of death from the first acute attack. Methods After excluding posttraumatic, postsurgical, and post-ERCP acute pancreatitis, we selected 192 consecutive patients admitted in the first instance to our center for a first attack, distinguishing between patients who died and patients who survived. We used Cox's model to analyze the prognostic weight of variables available within 24 h of admission (sex, age, alcohol intake, smoking habits, 17 biochemical tests, body mass index, chest X-rays, body temperature, and shock status). Results Seventeen (8.8%) patients died; mortality showed a decreasing trend over the period of years considered and was correlated, among other things, with necrotizing type of pancreatitis, idiopathic etiology, and shock status on admission.  相似文献   
32.
A significant decline of CD3 cell detected by rosettes and a significant increased of B cell populations were observed. The total CD3+, helper CD4+ and suppressor CD8+ T-cell subsets showed no significant variation em relation to sex, age thymectomy and corticotherapy by monoclonal antibodies.  相似文献   
33.
Purpose: Our purpose was to examine implantation of singleton pregnancies achieved following various assisted reproductive technologies (ARTs) through the appearance and rising titers of serum human chorionic gonadotropin (hCG) levels. Methods: A total of 114 singleton pregnancies resulting from in vitro fertilization and intrauterine insemination was analyzed. Patients were divided into five groups according to the type of ovarian stimulation protocol [gonadotropin stimulation with/without the use of gonadotropin-releasing hormone agonist (GnRHa), long protocol, or flare-up technique] and to the day of embryo transfer (day 2 or day 3 after oocyte retrieval). Serial serum hCG levels were measured between 10 and 25 days after fertilization and log-transformed. Linear regression analyses were performed and extrapolated to hCG = 10 mIU/ml (hCG 10 ), which was used as an estimate of detectable implantation. The slopes of the regression lines were used to estimate the rising speed of hCG. Results: There were no significant differences in the days of hCG in maternal serum to reach 10 mIU/ml (implantation) or in the slopes of the regression lines for all five studied groups. Conclusions: The appearance of hCG in maternal serum was used to assess the time of clinically detectable implantation. Furthermore, because hCG production is a marker of trophoblastic activity, its serum doubling time was used as an indicator of embryo quality. Results showed that in various ART protocols with and without GnRHa, there were no significant differences in implantation time or embryo quality. Embryo development in early pregnancy follows a preprogrammed-timing schedule and depends mainly on the embryonic age of the health, successfully implanted conceptus.  相似文献   
34.
Purpose The goal of the study is to evaluate utility of contrast enhanced ultrasound (US) with carbon dioxide microbubbles in evaluation of hepatic lesions.Methods Twenty eight patients with single or multiple t hepatic lesions (11 hepatocellular carcinoma, 8 hemangiomas, 5 metastases, 1 adenoma, 1 focal nodular hyperplasia, 2 regenerative nodules) were examined. US exam was performed during intraarterial injection of 10 ml of CO2 through the same catheter employed for liver arteriography. The US exam was videotaped in its salient phases. Characteristics of enhancement were evaluated and correlated with histological findings or patient follow up.Results Sonographic angiography clearly demonstrated vascularization of the lesions. Hepatocellular carcinoma, hemangioma, metastases, focal nodular hyperplasia, and regenerative nodules had very characteristic patterns. The injection of CO2 allowed detection of small additional nodules.Conclusion Sonographic angiography can improve characterization and staging of hepatic tumors. Low cost and the simplicity of the technique should encourage further experimentation.  相似文献   
35.
The SENCAR (sensitive to carcinogenesis) mouse is a unique tool for investigating the interaction between a specific defect in intracellular signaling, dietary calcium, and metabolic bone disease. The SENCAR mouse was developed by selective breeding for enhanced sensitivity to two-stage carcinogenesis. Its major genetic defect, which renders it exquisitely sensitive to stimulation with diacylglycerol or phorbol esters, is in the regulatory domain of protein kinase C, one of the primary intracellular mediators of hormonal effects. At sexual maturity, SENCAR mice are large and have big bones, but our previous pharmacokinetic studies showed that they accumulate lesscalcium under normal conditions and lose more calcium under adverse conditions than do other, standard strains of mice. To histologically define the effect of low dietary calcium on bone metabolism, we performed histomorphometric analysis of tetracycline-labeled sections of femoral bone from male SENCAR mice maintained on calcium-sufficient and calcium-deficient diets during the critical period from 10 to 14 weeks of age. The bone volume, absolute osteoid volume, and mineral apposition rate were lower at 14 than at 10 weeks of age in SENCAR mice fed 0.02 or 0.6% calcium diets. Calcium deficiency increased the architectural disarray and the probability of observing focal discontinuities in the growth plate. Thus, characteristic features of impaired bone metabolism (low bone volume and apposition rate) develop early in SENCAR mice and are exacerbated by low dietary calcium. Detailed examinations of the histology and biochemistry of SENCAR mouse bone will provide insights into the mechanisms by which specific defects in the signal transduction of protein kinase C contribute to impaired bone metabolism.  相似文献   
36.
37.
This article is a retrospective study comparing the efficacy of Regnauld arthroplasty to first ray osteotomies for the treatment of hallux valgus. One hundred consecutive cases of Regnauld arthroplasties were compared with 100 consecutive first ray osteotomies. One hundred fourty-one patients were available for follow-up, and based on clinical/radiographic examinations, 72 were treated with the osteotomy protocol (group A) and 69 with Regnauld arthroplasty (group B). Age at surgery, clinical symptoms, and preoperative radiologic findings were similar for the 2 groups; there was a preponderance of female patients (90%). The average follow-up was 49 months in group A and 51 months in group B. Clinical evaluation showed in the osteotomy group a more stable correction (79% v 49%), greater pain reduction (measured in a visual analog scale from 0 = pain free to 10 = deep intolerable pain), increased residual articular excursion of the first metatarsophalangeal joint (27 degrees of active dorsiflexion from neutral position v 8 degrees ), and less presence of central metatarsalgia (15% v 34%) (P <.05). The radiographic evaluation expressed more stable correction values in group A for the following parameters: joint preservation, sesamoid position, intermetatarsal angle (7 degrees v 12 degrees ), abduction angle of the hallux (14 degrees v 20 degrees ), and proximal articular set angle (8 degrees v 18 degrees ) (P <.05).  相似文献   
38.
We compared the effectiveness of Ca2+ entering by Na+/Ca2+ exchange with that of Ca2+ entering by channels produced by membrane depolarization with K+ in inducing catecholamine release from bovine adrenal chromaffin cells. The Ca2+ influx through the Na+/Ca2+ exchanger was promoted by reversing the normal inward gradient of Na+ by preincubating the cells with ouabain to increase the intracellular Na+ and then removing Na+ from the external medium. In this way we were able to increase the cytosolic free Ca2+ concentration ([Ca2+]c) by Na+/Ca2+ exchange to 325 ± 14 nM, which was similar to the rise in [Ca2+]c observed upon depolarization with 35 mM K+ of cells not treated with ouabain. After incubating the cells with ouabain, K+ depolarization raised the [Ca2+]c to 398 ± 31 nM, and the recovery of [Ca2+]c to resting levels was significantly slower. Reversal of the Na+ gradient caused an −6-fold increase in the release of noradrenaline or adrenaline, whereas K+ depolarization induced a 12-fold increase in noradrenaline release but only a 9-fold increase in adrenaline release. The ratio of noradrenaline to adrenaline release was 1.24 ± 0.23 upon reversal of the Na+/Ca2+ exchange, whereas it was 1.83 ± 0.19 for K+ depolarization. Reversal of the Na+/Ca2+ exchange appeared to be as efficient as membrane depolarization in inducing adrenaline release, in that the relation of [Ca2+]c to adrenaline release was the same in both cases. In contrast, we found that for the same average [Ca2+]c, the Ca2+ influx through voltage-gated channels was much more efficient than the Ca2+ entering through the Na+/Ca2+ exchanger in inducing noradrenaline release from chromaffin ceils. This greater effectiveness of membrane depolarization in stimulating noradrenaline release suggests that there is a pool of noradrenaline vesicles which is more accessible to Ca2+ entering through voltage-gated Ca2+ channels than to Ca2+ entering through the Na+/Ca2+ exchanger, whereas the adrenaline vesicles do not distinguish between the source of Ca2+.  相似文献   
39.
This work describes the results of the controlled crosslinking of collagen matrices by glutaraldehyde based on a double protection strategy, glutaraldehyde acetals and lysine protonation due to the acidic conditions of acetal formation. Materials crosslinked by this approach were characterized by thermal stability comparable to those obtained by conventional procedures with mechanical properties expected for bioprosthesis manufacture and with a higher stability toward collagenase hydrolysis. The integrity of the microfibrillar structure was confirmed by optical and scanning electronic microscopy. The results indicate that the glutaraldehyde acetals procedure may be of potential use for the crosslinking of bovine pericardium used in the manufacture of bioprosthetic devices. Advantages may be related to the production of materials with homogeneous crosslinking distributions, associated with better definition in the nature of the chemical link that they introduce, due to a better distribution of glutaraldehyde within the tissue matrix before the crosslinking reaction is allowed to occur. As a result, materials with improved biological and mechanical properties are expected.  相似文献   
40.
Ten protein coding loci (6‐PGD, A1‐AT, ACP1, CaII, ESD, GC, GPX1, Hbβ, PGM1, and TF) were analyzed in the Mbenzele Pygmies from the Central African Republic. The frequency data were used to calculate the genetic distances between Mbenzele Pygmies and other African groups. In the principal coordinate plot of FST genetic distances, the Mbenzele cluster together with other Pygmies of the western cluster, the Biaka from C.A.R., Gielli from Cameroon, and Babinga from Congo. By contrast, they are considerably distanced from other Pygmy groups of the eastern cluster (Twa from Rwanda, Mbuti from Zaire). Genetic distances obtained using protein loci were compared with those based on microsatellite loci. The two distance matrices are insignificantly correlated (r = 0.268; one tail probability = 0.332), and the main difference is in the higher genetic affinity between the Mbenzele and Biaka Pygmies observed at the protein level. Although reasons underlying the discrepancy between inter‐populational variation at protein and DNA loci are not established with certainty, the comparison suggests that the genetic distance between the Mbenzele and Biaka Pygmies at microsatellite loci could have been shaped by genetic drift. Am. J. Hum. Biol. 14:9–14, 2002.© 2002 Wiley‐Liss, Inc.  相似文献   
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