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1.
The use of additional epidural sympathetic block during and after microvascular surgery in the lower extremities to prevent vasospasm is generally agreed on. However, a significant fall in the perfusion rate of the transplants was seen after application of bupivacaine (Marcain) via the epidural catheter. This effect has, to our knowledge, not been described before and is probably caused by the sympathectomy effect of this type of analgesia.  相似文献   
2.
Background: Tight perioperative control of blood glucose improves the outcome of diabetic patients undergoing cardiac surgery. Because stress response and cardiopulmonary bypass can induce profound hyperglycemia, intraoperative glycemic control may become difficult. The authors undertook a prospective cohort study to determine whether poor intraoperative glycemic control is associated with increased intrahospital morbidity.

Methods: Two hundred consecutive diabetic patients undergoing on-pump heart surgery were enrolled. A standard insulin protocol based on subcutaneous intermediary insulin was given the morning of the surgery. Intravenous insulin therapy was initiated intraoperatively from blood glucose concentrations of 180 mg/dl or greater and titrated according to a predefined protocol. Poor intraoperative glycemic control was defined as four consecutive blood glucose concentrations greater than 200 mg/dl without any decrease in despite insulin therapy. Postoperative blood glucose concentrations were maintained below 140 mg/dl by using aggressive insulin therapy. The main endpoints were severe cardiovascular, respiratory, infectious, neurologic, and renal in-hospital morbidity.

Results: Insulin therapy was required intraoperatively in 36% of patients, and poor intraoperative glycemic control was observed in 18% of patients. Poor intraoperative glycemic control was significantly more frequent in patients with severe postoperative morbidity (37% vs. 10%; P < 0.001). The adjusted odds ratio for severe postoperative morbidity among patients with a poor intraoperative glycemic control as compared with patients without was 7.2 (95% confidence interval, 2.7-19.0).  相似文献   

3.
Pathophysiological aspects of brain edema   总被引:16,自引:0,他引:16  
Summary Two mayor types of brain edema, related to two different pathomechanisms, can be recognized: 1)cytotoxic type-where the main feature is the swelling of cellular elements of brain parenchyma and 2)vasogenic type-where an increased vascular permeability leading to accumulation of edema fluid inthe extracellular spaces plays the principal role. In this type of edema, there is a close interrelationship between extravasation of serum proteins and retention of water in the brain tissue. In theischemic brain edema both cytotoxic and vasogenic mechanisms are involved. A biphasic opening of the blood-brain barrier, associated with vasogenic edema, is observed following release of major cerebral artery occlusion. The first opening of the barrier is related to a reactive hyperemia which follows promptly recirculation. The second opening, recognizable after a delay, is associated with a severe ischemic brain tissue injury.Dedicated to Prof. F. Seitelberger on the occasion of his seventieth birthday  相似文献   
4.
5.
Several metabolic and hormonal parameters were evaluated in blood of two human subjects during simulation of an extended saturation dive. Increases in creatine kinase and an upward trend in cholesterol and glucose were observed after decompression. The levels of TTH and thyroxin went up in both subjects during exposure. The significant changes in cortisol, ACTH, insulin and C-peptide were a fingerprint of stress-reaction. After eight days of recovery most of the parameters returned to baseline values. The investigation suggests that the recompression treatment table did not cause pathological changes in the biochemical and hormonal parameters of humans.  相似文献   
6.
BACKGROUND: The role of local excision for pT2 distal rectal cancer has been challenged because of the observation of high rates of lymph node metastases and local failure. However, neoadjuvant chemoradiation therapy (CRT) has led to increased local disease control and significant tumor downstaging, possibly decreasing rates of lymph node metastases. In this setting, a possible role for local excision of ypT2 has been suggested. METHODS: A total of 401 patients with distal rectal cancer underwent neoadjuvant CRT. Tumor response assessment was performed after at least 8 weeks from CRT completion. One hundred and twelve patients with complete clinical response were not immediately operated on and were excluded from the study, and 289 patients with incomplete clinical response were managed by radical surgery. Patients with final pathological stage ypT2 were analyzed to determine the risk of unfavorable pathological features that could represent unacceptable risk for local failure after local excision. RESULTS: Eighty-eight (30%) patients had ypT2 rectal cancer. Final ypT status was not associated with pretreatment radiological staging (p = 0.62). ypT status was significantly associated with the risk of lymph node metastases, risk of perineural and vascular invasion, and recurrence (p = 0.001). Lymph node metastases were present in 19% of patients with ypT2 rectal cancer. The risk of lymph node metastases in ypT2 was associated with the presence of perineural invasion (47% vs 4%; p = <0.001), vascular invasion (59% vs 6%; p < 0.001), and decreased mean interval CRT surgery (12 vs 18 weeks; p < 0.001), but not with mean tumor size (3.2 vs 3.1 cm; p = 0.8). Disease-free and overall survival rates were significantly better for patients with ypT2N0 (p = 0.02 and 0.006, respectively). Fifty-five (63%) patients with ypT2 had at least one unfavorable pathological feature for local excision (lymph node metastases, vascular or perineural invasion, mucinous type or tumor size >3 cm). CONCLUSION: Lymph node metastases were present in 19% of patients with ypT2 and were significantly associated with poor overall and disease-free survival rates. The risk of lymph node metastases could not be predicted by radiological staging or tumor size. Radical surgery should be considered the standard treatment option for ypT2 rectal cancer after CRT.  相似文献   
7.
There was a study of 422 in-patient subjects of the therapeutic profile. Endoscopy enabled to discover mucous coat erosions of the antral part of the stomach associated with Helicobacter pylori and absence of ulcer in the anamnesis in 8.7% of them (more frequently in women). As many as 81% of such patients belonged to patients with the ischemic heart disease. Erosive gastropathy is accompanied by the activity of the chronic inflammation response in the duodenum mucous coat that is most evident in IHD patients.  相似文献   
8.
The significance of life stress, coping, and social support was examined in relation to depressive symptomatology in a sample of 160 asymptomatic and mildly symptomatic HIV-antibody-positive (HIV+) men. The participants (mean age = 32 years) were interviewed about the life stress that they had experienced in the previous 6  相似文献   
9.
Cells were isolated by successive dissociation of human placenta in dispase and collagenase solutions and separated by centrifugation in Ficoll-Verografin gradient. Cell suspension was enriched with macrophages by adhesion to plastic followed by washing with RPMI-1640. Isolated placental macrophages can be cultured for a long time. Cell culture homogeniety assessed by various methods was equal or exceeded 95%. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 125, No. 5, pp. 579–582, May, 1998  相似文献   
10.
Background: Spinal substantia gelatinosa (SG) is a site of action of administered and endogenous opioid agonists and is an important element in the system of antinociception. However, little is known about the types of neurons serving as specific postsynaptic targets for opioid action within the SG. To study the spinal mechanisms of opioidergic analgesia, the authors compared the action of [mu]-opioid agonist [D-Ala2, N-Me-Phe4, Gly5-ol]-enkephalin (DAMGO) on SG neurons with different intrinsic firing properties.

Methods: Whole cell patch clamp recordings from spinal cord slices of Wistar rats were used to study the sensitivity of SG neurons to DAMGO.

Results: Three groups of neurons with distinct distributions in SG were classified: tonic-, adapting-, and delayed-firing neurons. DAMGO at 1 [mu]m concentration selectively hyperpolarized all tonic-firing neurons tested, whereas none of the adapting- or delayed-firing neurons were affected. The effect of DAMGO on tonic-firing neurons was due to activation of G protein-coupled inward-rectifier K+ conductance, which could be blocked by 500 [mu]m Ba2+ and 500 [mu]m Cs+ but increased by 50 [mu]m baclofen. As a functional consequence of DAMGO action, a majority of tonic-firing neurons changed their pattern of intrinsic firing from tonic to adapting.  相似文献   

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