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991.
Despite recent advances in intensive care medicine, acute lung injury and its more severe form, acute respiratory distress syndrome pose major therapeutic problems. While mechanical ventilation is integral to the care of these patients, its adverse consequences including ventilator-induced lung injury are determinants of disease progression and prognosis. Among several important ventilator parameters, the use of low tidal volumes is probably the most important feature of lung-protective mechanical ventilation. Intensivists should be trained to recognize acute lung injury and acute respiratory distress syndrome and encouraged to use low-tidal-volume ventilation in clinical practice. Alternative modes of ventilation such as high-frequency ventilation and prone position should be reserved for selected patients in whom conventional lung-protective ventilation strategies have failed.  相似文献   
992.
BACKGROUND: Protein energy wasting is a maladaptive metabolic state often associated with inflammation, which is common in patients with chronic kidney disease (CKD). METHODS: A literature search was performed using MEDLINE and the reference lists of relevant review articles. The following key words were used in the MEDLINE search: "cytokines", "inflammation", "protein metabolism", "acute-phase protein", "cachexia", "chronic kidney disease", "end-stage renal disease" and "hemodialysis". The search was limited to English-language articles. RESULTS: While experimental models have shown that uremic animals are more prone for proteolysis, the results from the human studies are controversial. Intradialytic loss of amino acids and activation of proinflammatory cytokines lead to protein catabolism during hemodialysis (HD). At the whole-body level, intradialytic parenteral nutrition (IDPN) increases protein synthesis and decreases proteolysis. Amino acid infusion during HD increases muscle protein synthesis, but does not decrease protein catabolism. Activation of interleukin-6 during HD induces protein catabolism, impairs amino acid utilization for protein synthesis and increases acute-phase protein synthesis. CONCLUSION: The changes in albumin, fibrinogen and muscle protein kinetics during HD could be due to competing and complementary effects of availability of amino acids and activation of proinflammatory cytokines.  相似文献   
993.
OBJECTIVE: Alpha-blockers are the most widely used agents to treat lower urinary tract symptoms in males, and switching between alpha-blockers is a frequent management option when the desired effect could not be obtained. There is no data in the literature that reveal the outcome of treatments with different alpha-blockers within the same patient. We sought the answer to this question in a setting where the same individuals were treated with two different agents during different time frames. MATERIALS AND METHODS: Forty males with benign prostatic hyperplasia (BPH) applying to the Department of Urology with lower urinary tract symptoms (LUTS) were enrolled in the study consecutively. Patients were evaluated with detailed medical history, IPSS forms, digital rectal examination (DRE), urinary ultrasound, PSA, and uroflowmetry. The subjects received terazosin 5 mg daily for 3 months, and controlled release form of alfuzosin 10 mg daily for another 3 months, leaving a 1-month clearance period in between. The above-mentioned detailed evaluations were carried out before and after each alpha-blocker regimen. RESULTS: Mean age and PSA level was 63.3 +/- 1.6 years (45-80), and 2.1 +/- 0.4 ng/ml (0.16-6.3 ng/ml). IPSS and Q (max) values before treatment with terazosin and alfuzosin were similar. Improvements in IPSS and Q (max) values after treatments with both terazosin and alfuzosin were significant. There was no statistically significant difference between the drugs in terms of percent improvements in IPSS and Q (max) with alpha-blocker treatment. No untoward effect except for transient dizziness in one case with terazosin treatment was encountered. CONCLUSION: Different alpha-blockers, which are used during different time frames in the same individuals, provide similar efficiency outcome. When the desired effect in the treatment for BPH could not be obtained with one alpha-blocker, there may not be any benefit in switching to another one.  相似文献   
994.

Background/Purpose

Although ingestion of alkali-based and/or hypochlorite-based household cleaners as well as strong acids remains a major cause of esophageal wall injury, little is known about the mechanisms that underlie the injury response to these toxic agents. This study examined the roles of vascular dysfunction and inflammation to the esophageal injury response to different caustic substances in mice.

Methods

The esophageal responses to sodium hydroxide (10%, 5%, and 2.5%), potassium hydroxide (10%, 5%, and 2.5%), sodium hypochlorite (5.25%), and hydrochloric acid (10%, pH 2) were evaluated by intravital videomicroscopy and histopathology. Intravital microscopy was used to monitor changes in the diameter of arterioles and venules, the adhesion and movement of leukocytes in venules, and the time of cessation of arteriolar blood flow in mouse esophagus. The esophageal mucosa was exposed to caustic substances for 0 to 60 minutes before evaluation.

Results

The higher concentrations of sodium hydroxide and potassium hydroxide elicited rapid stasis in both arterioles and venules, which was accompanied by arteriolar constriction and thrombosis. An accumulation of adherent leukocytes in venules was not observed with any agent. Histopathological evaluation revealed marked cellular and interstitial edema in the mucosa with alkali, whereas hydrochloric acid and sodium hypochlorite decreased the thickness epithelial layer.

Conclusion

These findings suggest that ischemia and thrombosis are dominant processes, whereas inflammation is less important in the pathogenesis of acute corrosive injury to the esophageal mucosa.  相似文献   
995.
996.
997.
BACKGROUND: A number of experimental studies have suggested that cyclosporine (CsA) toxicity induces cardiac modifications which may cause diastolic dysfunction over the course of time. Doppler echocardiography with tissue Doppler imaging (TDI) could consistently detect diastolic dysfunction. The purpose of this study was to assess diastolic dysfunction using C2 monitoring of CsA exposure in stable renal transplant patients. PATIENTS AND METHODS: Seventy-eight kidney recipients including 42 men and 36 women of overall mean age of 52 +/- 9 years were obtained in 47 living and in 31 cases from cadaveric donations over 12 or more months after transplantation using cases from CsA, mycophenolate mofetil, and steroid. C2 levels were measured by an enzyme multi-immune assay technique. The patients underwent conventional and Doppler echocardiography with TDI. RESULTS: The patients were divided into 2 groups according to C2 levels less than 500 mug/L (group 1, n = 40) versus greater than 500 mug/L (group 2, n = 38). The demographic parameters, serum creatinine and lipid levels, systolic and diastolic blood pressures, number and type of antihypertensive medications, and conventional echocardiographic parameters did not differ significantly between the groups. However, group 1 patients showed significantly higher isovolumic relaxation time (109 +/- 27 vs 86 +/- 14 ms), early diastolic deceleration time (189 +/- 52 vs 137 +/- 59 ms), and lower values of E velocity (56 +/- 32 vs 92 +/- 27 cm/s) and E/A ratios (0.81 +/- 0.23 vs 1.15 +/- 0.46) than group 2. TDI studies revealed significantly lower E'/A' (0.76 +/- 0.25 vs 1.09 +/- 0.32, P < .05) in group 1 versus group 2. CONCLUSION: The data suggested that the higher C2 levels may induce diastolic dysfunction in the hearts of kidney recipients without impairment of contractile performance.  相似文献   
998.
The persistent primitive hypoglossal artery (PPHA) is one of the pairs of arterial connections that exist in the human embryo between the developing anterior and posterior circulation. Normally the PPHA arises from the cervical internal carotid artery (ICA) and passes through the hypoglossal canal to join the caudal basilar artery (BA). In most cases the vertebral arteries (VA) are either hypoplastic or aplastic and the posterior communicating arteries (PComA) are absent; thus, the main supply to the posterior circulation comes from the internal carotid via the PPHA in an antegrade fashion. Atherosclerotic plaques in the ICA and PPHA present with ischemic symptoms of both the carotid and vertebrobasilar systems. We report a case of a 53-year-old female who presented with a transient episode of left lower extremity numbness and weakness. Work-up with computed tomography (CT) and magnetic resonance imaging (MRI) showed a small watershed infarct in the right middle cerebral artery (MCA)/posterior cerebral artery (PCA) territory. Diagnostic angiography revealed severe proximal stenosis of the cervical ICA and presence of a PPHA just above the stenosis with retrograde filling from the vertebrobasilar junction to the distal cervical ICA. The patient underwent a carotid endarterectomy with intraoperative EEG monitoring. Intraoperative blood flow measurements were made before and after endarterectomy showing evidence of reversal of blood flow to a normal antegrade fashion. The postoperative angiogram showed resolution of the right ICA stenosis and persistence of the PHA. To our knowledge this is the first case report of a PPHA exhibiting reversal of blood flow from the posterior into the anterior circulation. Awareness of this embryological anomaly and its interaction with acquired atherosclerotic disease will minimize misinterpretation of vascular diagnostic studies.  相似文献   
999.
The most common etiology of nasal defects that require reconstruction is skin cancer, particularly basal cell carcinoma, the most common nasal skin cancer, as well as squamous cell carcinoma, and melanoma. Reconstruction of extensive nasal defects including nasal bone, septum, and esthetically defined units of the nose always represent with certain difficulties. Forehead flaps and free flaps can be utilized for reconstruction of extensive nasal defects. The forehead flap is a reliable and well-established reconstructive option for management of extensive nasal defects. We aimed to compare the esthetic and functional results of forehead flaps and free flaps for reconstruction of extensive nasal defects.  相似文献   
1000.
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