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161.
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   
162.
小红参滴丸的制备工艺研究   总被引:2,自引:0,他引:2  
目的 :研究小红参滴丸的最佳成型工艺条件。方法 :采用正交试验法 ,考察了提取物与基质配比、滴制温度、滴头口径大小等因素TLC定性鉴别。结果 :药物提取物 :基质 (1:1.4 ) ,滴制温度 85℃ ,滴头口径 1/ 2mm (内径 /外径 )。滴速 (8± 2 )滴 /min ,滴距 8cm ,冷却剂温度 (4± 2 )℃ ,柱高 6 0cm进行滴制 ,滴丸的成型率最高。结论 :证明此工艺可行 ,成品得率高 ,符合滴丸剂的质量标准。  相似文献   
163.
The effect associated with the substitution of adenine (A) for guanidine (G) in the promoter region of the apolipoprotein AI gene (?75 bp) with plasma apo AI and high-density lipoprotein (HDL) levels was investigated in the European Atherosclerosis Research Study (EARS). This is a study of healthy offspring (cases) of fathers who had suffered premature myocardial infarction (MI) before age 55 years (n = 565) and age- and sex-matched controls (n = 1,078) from 12 European countries, divided into 5 regions based on geography and language. The frequency of the polymorphism was not significantly different among the regions and the relative frequency of the rare A allele was similar in cases and controls (0.159 vs. 0.142) combining data from all regions. Individuals with one or more A allele had significantly higher plasma apo AI levels (P < 0.05) than individuals homozygous for the G allele. This effect was consistent in all regions. The data were analyzed separately in males and females. In females, those with one or more A allele had significantly higher apo AI levels (P = 0.05) than individuals homozygous for the G allele, and this raising effect of the A allele was greater in cases than controls for both apo AI (5.23% vs. 1.56%) and HDL (4.48% vs. 1.89%). In males, the A allele was associated with higher levels of apo AI and HDL, but the effect was much smaller and the differences did not reach statistical significance. In the females, where the effect of the A allele was strongest, the effect on apo AI associated with genotype was evident in non-smokers, and individuals with one or two A alleles had 3.6% higher apo AI and 3.14% higher HDL levels than individuals homozygous for the G allele. However, in the female smokers the raising effect of the A allele was greatly reduced (0.56%). Thus genetic variation in the promoter region of the apo AI gene is associated with differences in apo AI and HDL levels in healthy individuals throughout Europe, but the effect is modulated by gender, environmental factors such as smoking, and a family history of MI.  相似文献   
164.
Nerve conduction as a means of estimating early post-mortem interval   总被引:2,自引:0,他引:2  
Summary Methods in current practice for ascertaining time of death are largely based on the cooling of the body after death and are somewhat unreliable. A theoretica relationship is known to exist between the decline in the properties defining nerve conduction and time after death caused by the gradual cessation of metabolic activity in nerves. A number of such properties were measured in rats during life and after death. In most cases the relationship was found to be inconsistent. The chronaxie of the strength duration curve for the sciatic nerve was, however, found to increase consistently and reproducibly in a linear fashion over the first 90 min after death to a plateau value which was maintained beyond 135 min. These findings are discussed as the possible basis of a forensic method of determining the duration of the “post mortem interval” within the first few hours after death.   相似文献   
165.
166.
The greater than 40-fold range of voluntary salt intake in humans requires corresponding adjustments in renal excretion to maintain balance. Although many mechanisms have been implicated in the regulation of salt output by the kidney, surprisingly little consideration has been given to their quantitative significance and possible interaction. This survey summarizes the effects of changes in glomerular filtration rate, proximal peritubular physical factors, and plasma concentrations of aldosterone and atrial natriuretic factor (ANF), singly and in combination, on the level of salt excretion. Contrary to expectation, even large increases in filtration or decreases in proximal reabsorption have only minor natriuretic effects, due to constancy of fractional reabsorption in downstream nephron segments. Lack of aldosterone release increases salt excretion as much or more than the upstream mechanisms, whereas ANF-induced inhibition of reabsorption in the medullary collccting duct has the largest effect. It may be concluded, therefore, that the potency of these natriuretic factors increases with distance along the nephron, even though each is operating on a progressively small tubular load. However, none of the mechanisms, in isolation, is sufficient to explain salt balance over the range of voluntary intake. Combination of factors demonstrates synergism rather than simple additivity, resulting in more than enough reserve capacity for salt excretion.  相似文献   
167.
In a retrospective study the prognostic significance of nuclear DNA content was investigated, as measured by flow cytometry, of the tumor specimens from 212 women with nonpretreated FIGO stage IB and II cervical cancer. One-hundred and thirty cases (62%) were found to be diploid, whereas 82 (38%) were aneuploid. Univariate analysis of the follow-up data showed an increased relative risk (RR) for recurrence free survival (RFS) for stage II tumors (RR = 1.87, 95% CI: 1.13–3.10, P = 0.015) and for age (RR = 1.52, 95% CI: 0.66–3.52 and RR = 2.35, 95% CI: 1.19–4.65, P = 0.032). Ploidy showed a relative risk of 1.33 (95% CI: 0.83–2.13, NS). In addition, univariate analysis of overall survival (OS) revealed similar results. For the subgroup of patients with primary surgery ( n = 151), positive pelvic nodes (RR = 5.38, 95% CI: 2.70–10.71, P = 0.0001) and parametrial extension (RR = 2.53, 95% CI: 1.24–5.17, P = 0.011) were significant factors for OS after univariate analysis, the estimated effects on RFS were slightly smaller. Multivariate analysis of RFS for the whole study population showed age, histologic grade and stage with a slightly increased risk, but no effect was significant. Ploidy with an RR of 0.97 (95% CI: 0.58–1.62) seems to have no influence on prognosis. For the subgroup with primary surgery, ploidy again failed statistical significance with an RR of 1.20 (95% CI: 0.58–2.49). Our results suggest that abnormalities of the nuclear DNA content in this homogeneous group of patients are associated with clinical and morphological prognosticators, however, ploidy is not an independent prognostic factor for RFS, or for the whole study population or for the subgroup with primary surgery.  相似文献   
168.
In the present study, a kinematic analysis was made of unconstrained, natural prehension movements directed toward an object approaching the observer on a conveyor belt at one of three constant velocities, from one of three different directions (head-on or along the fronto-parallel plane coming either from the subject′s left or right). Subjects were required to grasp the object when it reached a target located 20 cm directly in front of the hand′s start position. The kinematic analysis revealed that both the transport and grasp components of the movement changed in response to the experimental manipulations, but did so in a manner that guaranteed that, for objects approaching from a given direction, hand closure would begin at a constant time prior to object contact (regardless of the object’s approach speed). The kinematic analysis also revealed, however, that the onset of hand closure began earlier with objects approaching from the right than from other directions – an effect which would not be predicted if time to contact was the key variable controlling the onset of hand closure. These results, then, lend only partial support to the theory that temporal coordination between the transport and grasp components of prehension is ensured through their common dependence on time to contact information. Received: 20 September 1996 / Accepted: 16 June 1997  相似文献   
169.
Recent experimental and clinical studies suggest that tumour-induced angiogenesis may be an important step in the evolution of malignant tumours, and may be related to prognosis. In our study we examined 42 cases of breast carcinoma (mean age: 56.76 ± 13.5), 21 with lymph node metastases and 21 without. Angiogenesis was evaluated after immunohistochemical staining of tumour vessels, using polyclonal antibody to factor VIII related antigen (VIIIR-Ag) and counting of the three most active areas of neovascularization. In the same manner we counted the microvessels in lymph node metastases. The mean vessel count of node-negative cases (51.16 ± 19.32) did not differ significantly from node-positive cases (45.66 ± 17.44). In contrast patients younger than 50 years had much higher mean vessel counts (54.04 ± 16.47) than did patients older than 70 years (38.03 ± 16.73) producing a P value of ≤0.05. No association was found between tumour size and mean vessel count, nor was there any significant difference between grade I (45.94 ± 16.54), grade II (53.13 ± 23.22) and grade III tumours (51.71 ± 20.64). When we compared the mean vessel count of primary tumours with those of node metastases, we found much lower counts in the latter ( P ≤0.01). The differences in our results from previous studies, probably reflect the heterogeneity which exists between different tumours in their ability to induce angiogenesis. Additionally, there is some evidence in our study that angiogenesis is possibly related to patient age and probably depends on differences in the tumour stroma.  相似文献   
170.
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