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41.
目的:探索可早期预测严重败血症病人死亡的临床和实验室指标或系统模型。方法:对ICU连续收治的26例严重败血症病人行前瞻性观察28天,分析其死亡的相关临床和实验室指标。结果:共有14人(54%)死亡,多死于第1周内(74%)。根据循环中的细胞间粘附分子-1水平能早期预测其脏器衰竭和死亡。一些临床指标水平在死亡病人与生存病人之间差别较大,其中包括血总胆红素、pH值、红细胞压积、氧合指数、动静脉血氧差、四项SIRS指标和一些血流动力学指标等。结论:综合上述指标可以尝试建立起了一个能够早期评估病人死亡可能性的积分系统。  相似文献   
42.
In migraine, headache severity varies with age. As a consequence, the effectiveness of medication may also depend on a patient's age. The purpose of this study was to assess the combined effect of age and drug treatment on headache characteristics. Using data from clinical trials of sumatriptan in adolescents and adults, we show how the interaction between age and drug exposure can be parameterised as a covariate on a Markov model that describes the decline of headache severity over three clinically defined stages (no relief, relief and pain-free status). The model explains important clinical observations: (i) the rates at which the pain relief and pain-free status were attained were found to be inversely related to age; (ii) in placebo-treated patients, the mean transit time from 'no relief' to 'relief' is 3 h for young adolescents and increases to 6 h for patients aged ≥ 30 years; and (iii) sumatriptan reduces the transit time to 2 h, irrespective of age. These findings indicate that the therapeutic gain over placebo increases with age. Prospective studies of antimigraine drugs should take this relationship into account when extrapolating efficacy data from adults to adolescents.  相似文献   
43.
44.
Objective: The guiding criteria are considered the backbone of Chinese medicine. They have previously been described as functional features (symptoms) leading to the overall assessment of human functions on the basis of a regulatory (cybernetic) model referring to the I Ging. Methods: The Heidelberg model can explain symptoms such as created by "heat" on a rational physiological level. Results & Conclusion: The overall of physiological symptoms are shown as a schematic draft. The basis of "heat" is considered to be a general increase of microcirculation in the periphery. This leads to a couple of local pathophysiological consequences and sensations like 1) red tongue (the tongue is considered an embryological somatotopic system). 2) Sensation of warmth (by increase of capillary flow). 3) pre-inflammatory state, leading to pain modalities like "worse if pressed", as inflammations tend to be increasingly painful under pressure; 4) reddish skin, the mechanisms by which this is induced may include the release of substance P, therefore accompanied by burning sensation. Systemic pathophysiological consequences may include. Relative lack of fluid in the larger vessels, as fluid supplies peripheral capillary flow. This may lead to water saving mechanisms like thirst, dry mucosa with do, mouth, dry nose, dry lips, dry skin, and also dry stool, yellow and sparse urine.  相似文献   
45.
46.
MATERIAL: 28 stereotactic biopsies of organic brain processes (brain tumours) were performed in the years 1997-2000 in the Department of Neurosurgery, Medical University of Warsaw. In this series the lesions were located in corpus callosum in 5 patients, in basal nuclei in 9, and deeply in the white matter of cerebral hemispheres in 14. METHOD: The Baklund biopsy kit and Leksell's stereotactic frame were used, target localisation was based on the CT scan. Histological verification was based on hematoxillin--eosin staining, completed with histochemical evaluation if necessary. In 9 patients intraoperative smear evaluation was performed. RESULTS: Sensitivity of stereotactic biopsies was 86% (24/28), although the rate of conclusive biopsies was lower, being 60% (17/28). False negative results were observed in 14% of the patients (4/28). Analysis of the results revealed, that the sensitivity was not dependent on the size, neither on the location of the tumour, but was related to its morphology. The false negative results were obtained in the tumours with significant necrosis (as seen on CT scans). There were no surgical complications in this series. CONCLUSIONS: 1. Difficulties in stereotactic biopsies of brain tumours are associated mainly with tumour morphology. In tumours with marked necrosis, other degenerative changes or cystic ones, higher risk of non-conclusive biopsy may be expected. 2. Size of the tumour and its location do not affect the diagnosis based on the stereotactic biopsies. 3. In the polymorphic tumours, the policy to take biopsy material from different tumour sites, should be a rule, as different parts of the lesion may represent different stages of malignancy and histological evaluation of separate parts of the tumour may lead to inadequate oncological treatment.  相似文献   
47.

BACKGROUND:

The efficacy of angiotensin-converting enzyme (ACE) inhibitors is well documented in the treatment of chronic severe heart failure. Because pharmacological mechanisms of angiotensin II type 1 (AT1) receptor antagonists differ from the effects of ACE inhibitors, an additional positive effect can be expected by combining these drugs.

METHODS:

Sixty patients (mean age 68.3±10.0 years) with severe chronic heart failure receiving long term medication with digitalis, diuretics, ACE inhibitors and in part beta-blockers (68.3%) were randomly assigned after clinical recompensation to three groups: additional therapy with eprosartan (477.5±143.7 mg/day), telmisartan (65.9±17.7 mg/day) and control group according to a prospective study design. Hemodynamic measurements by impedance cardiography were performed before and during the observation period (9.6±3.4 days).

RESULTS:

Additional sartan treatment resulted in an improvement in cardiac output from 2.32±0.69 L/min to 3.12±1.24 L/min (P=0.003) in the eprosartan group and from 2.24±0.59 L/min to 2.76±0.91 L/min (P=0.001) in the telmisartan group; cardiac output in the control group did not increase. Furthermore, a significant decrease in total peripheral resistance was observed during treatment with eprosartan (23%, P=0.002) and telmisartan (18%, P=0.002). In the subgroup receiving combined therapy with beta-blockers, ACE inhibitors and AT1 antagonists, a significant increase in cardiac output was also observed.

CONCLUSIONS:

The additional treatment with AT1 receptor antagonists resulted in an increase in the cardiac output and a decrease in the peripheral resistance. This beneficial effect may be due to the additional property of sartans to block the interaction of locally and non-ACE-generated angiotensin II with their respective vascular and myocardial AT1 receptors.  相似文献   
48.
The intensive care unit at Queen Elizabeth Central Hospital (QECH) has 4 beds and offers level 2 care. A retrospective audit of all admissions to the unit during 2002 was carried out. There were a total of 339 admissions giving a bed occupancy rate of 82 %. Surgical patients made up 81 % of admissions. 45% of all admissions were ventilated. Overall mortality was 38%. Ventilated patients had a mortality of 71% compared with 10% for non-ventilated. Data are also presented for mortality within the surgical and paediatric surgical admissions.  相似文献   
49.
E mu-pim-1 transgenic mice are predisposed to develop lymphomas. Due to their low spontaneous tumour incidence and their increased sensitivity towards the lymphomagen ethylnitrosourea these mice may present an interesting model for short-term carcinogenicity testing. Here, we report on the further exploration of this transgenic mouse model with two additional carcinogens known to have, among others, the lymphohaematopoietic system as target, i.e. benzo[a]pyrene (B[a]P) and 12-O-tetradecanoylphorbol-13-acetate (TPA). B[a]P, given three times a week (by gavage) for 13 weeks at 4.3, 13 or 39 mg/kg body weight, resulted in a dose-related increase in lymphomas up to a 90% incidence in E(mu)-pim-1 mice during the observation period of 40 weeks. B[a]P also induced tumours of the forestomach within this observation period, though at a lower incidence and apparently equally effective in wildtype and transgenic mice. TPA, on the other hand, was unable to induce lymphomas (or tumours in any other organ) in either transgenic or wildtype animals within the observation period of 44 weeks, when applied dermally at the maximum tolerated dose of 3 microg/mouse, twice a week for 35 weeks. Molecular analysis showed that B[a]P-induced lymphomas in transgenic mice were of T-cell origin, 80% of which had elevated levels of c-myc expression. None of the lymphomas had increased N-myc expression and mutation analysis of the ras-gene family revealed a K-ras mutation in only one out of eight tumours investigated. Also, none of the lymphomas showed aberrant expression of p53 as determined by immunohistochemistry. It is concluded that the E mu-pim-1 mouse model will not be very suitable for short-term carcinogenicity testing in general: only genotoxic chemicals that have the lymphohaematopoietic system as target for carcinogenesis in wild- type mice, appear to be efficiently identified.   相似文献   
50.
Mucormycosis is a rare fungal infection of childhood, occurring mainly in patients with chronic illnesses such as diabetes and malignancies. The fungus seldom grows in culture and confirmation of the diagnosis depends on histologic examination of infected tissues. To date, the reported natural history of the disease has been rapid progression and a fatal outcome. Therefore, the importance of early diagnosis by tissue biopsy and early treatment with surgical debridement and systemic antifungal therapy cannot be overemphasized. The pulmonary system is the most common site for mucormycosis in patients with leukemia. We report what we believe to be the first successfully treated case of isolated muscular mucormycosis occurring in a child with biphenotypic acute leukemia. The diagnosis was made promptly by tissue examination at the time of surgical debridement. The patient was also given systemic amphotericin-B therapy.   相似文献   
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