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1.
PURPOSE: Bone healing is impaired in diabetes mellitus, particularly due to increased collagen breakdown. Recently, tetracyclines have been used to treat experimental bone defects because they have anticollagenolytic properties, and positive effects on the healing process have been obtained. The objective of this study was to develop a computer-assisted histomorphometric technique to quantitatively determine the amount of regenerating bone within experimental bone defects in a diabetic rodent model. MATERIALS AND METHODS: This study examined the effects of systemic doxycycline administration on the healing of tibial bone defects in healthy albino rats and in experimentally induced diabetic rats. Twenty-four female albino rats were assigned to 4 groups: diabetic, diabetic plus doxycycline, control, or control plus doxycycline. The standardized bone defects were histomorphometrically examined 10 and 30 days postoperatively. Histomorphometric analysis of the amount of new bone formation was performed using the Zeiss Vision image analysis program KS 400 (Kontron Elektron GmbH, Eching, Germany). RESULTS: At 10 days of healing, the diabetic groups exhibited inferior healing compared with the control groups in terms of the amount of new bone formation within the defects. However, the effect of doxycycline administration to the diabetic and control groups was not statistically different. At 30 days of healing, there were no statistically significant differences between the amount of newly formed bone in any of the groups. CONCLUSIONS: This study found that doxycycline administration did not significantly alter the amount of new bone formation during the healing of bone defects in control and diabetic rats.  相似文献   
2.
This article provides a brief overview of the changing nature of the concept of minor depression. It then discusses treatment studies conducted from 1980 to 1991 of patients diagnosed as neurotic depression, depressive neurosis or dysthymia, characterologic depression, "double depression" and minor depression or dysthymia, if there has been a full remission of a major depressive episode lasting at least six months prior to the development of dysthymia. Long-term treatment of chronic depression is also reviewed. Cognitive-behavioral intervention and marital therapy have been reported beneficial for patients diagnosed as having neurotic depression, characterological depression, or dysthymia. All studies of antidepressant drug treatment showed drugs to be efficacious and superior to placebo, with few differences found between drugs. In addition, they all showed the importance of analyzing the interactions between treatment and severity or diagnosis. Patients diagnosed as "double depression" also appear responsive to both psychosocial intervention and drug treatment; in general, however, these patients tend to have a poor long-term outcome and continued treatment is indicated. The most obvious finding to emerge from this review is that the diagnosis of minor depression is ambiguous, in large part because of the lack of defining criteria related to severity and course. The review also revealed that in addition to poorly defined subgroups, many studies lacked controls, had small sample sizes, inadequate and/or inconsistent measures of outcome, and limited follow-up. For these reasons, their findings cannot be considered conclusive. Finally, the literature revealed a dearth of controlled studies of psychosocial treatment for well defined subgroups of neurotic depression.  相似文献   
3.
The constant release of nitric oxide (NO) is essential to maintain basal cerebrovascular tone. Oxyhaemoglobin, liberated by lysis of red blood cells after subarachnoid haemorrhage binds NO and prevents its entry into vascular smooth muscle cells. While endothelium-dependent vasoconstriction is preserved, decreased levels of NO inhibit endothelium-dependent relaxation and may cause vasospasm. S-nitrosothiols are potent vasodilators and precursors of NO. The authors' aim was to determine whether S-nitroso-N-acetylpenicillamine (SNAP), a stable S-nitrosothiol compound, could reverse vasospasm in an experimental vasospasm model in rabbit. Experimental subarachnoid haemorrhage (SAH) was induced in 37 New Zealand white rabbits. The animals were divided into four groups. Control (no SAH), SAH only, SAH plus saline and SAH plus SNAP. SNAP (15 micrograms/kg/min) or 0.09% saline (equal volume) was infused 46 hours after induction of SAH. All animals were killed by perfusion fixation 48 hours after SAH occurred. Basilar arteries were removed, sectioned and their cross sectional areas were evaluated in a blind manner, by light microscopy and by using computer assisted morphometry. Experimental SAH elicited vasospasm in all animals of SAH only and SAH plus saline group. In animals treated with SNAP, arterial narrowing was markedly attenuated without producing systemic hypotension. This widening achieved statistical significance when compared to the arteries of the SAH only and SAH plus saline group (p < 0.01). This study indicates that the NO donor SNAP is a potentially useful drug to reverse cerebral vasospasm due to SAH.  相似文献   
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Two studies are reported. The first examined the factor structure of the Psychological Mindedness (PM) Scale, and the second reassessed the scale's predictive validity. A principal components analysis (varimax rotation) of the data of 256 psychiatric outpatients produced five factors that accounted for 38% of the variance. A tentative definition of PM based on these factors is proposed. For a subsample of 116 patients who attended at least four psychotherapy sessions, PM was unrelated to levels of functioning and psychosocial symptoms at admission and was positively associated with number of sessions attended, consistent with findings of a preliminary investigation. Not replicated were significant correlations between PM and outcome measures derived from therapists' and an independent rater's evaluations. Initially high PM was significantly related to patients' self-ratings of symptoms and problems after discharge.  相似文献   
6.
The emergence of different models of psychological healing from Freud to the present, and specific features which characterize "new" psychotherapies in contrast to psychoanalysis are examined. The author maintains that these represent a chronological evolution of therapeutic forms which are complementary and which portend the unification of the psychotherapies.  相似文献   
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BACKGROUND: Acute liver failure (ALF) carries a high mortality unless urgent orthotopic liver transplantation (OLT) is performed on time. Live donors are utilized to treat this irreversible condition first in pediatric cases and then in adults. Herein, we aimed to report our experience with live donors for ALF in a country of a deceased donor organ donation rate is only 1.5 per million people. METHODS: Among the 245 live donor liver transplantations (LDLT) performed from June 1999 to December 2005, 14 of them (6%) were performed for ALF in 8 pediatric and 6 adult cases. Right lobes were harvested for the adult cases whereas left lateral segments were harvested for pediatric cases, except one child transplanted with a right lobe graft. The etiology of the disease was; acute hepatitis B in four cases, hepatitis A in three cases, Wilson disease two cases, autoimmune hepatitis in two cases, and was unknown in three cases. RESULTS: Three-year graft and patient survival is 79% for these series. Five of the six adult patients and six of the eight pediatric cases survived after transplantation. There was not any donor mortality or major morbidity. CONCLUSIONS: LDLT offers a safe and effective modality of treatment for ALF for both pediatric and adult patients to overcome the problem of organ shortage especially in countries where the chance of receiving an organ from a deceased donor is low.  相似文献   
9.
The aim of this study was to evaluate the clinical effectiveness of distal forearm intravenous regional anaesthesia (IVRA) with the tourniquet applied 3 cm above the wrist. One hundred and twenty patients undergoing out-patient hand surgery were operated for 13 different hand problems under distal forearm IVRA, using 10 ml of a solution containing 1.5 mg/kg prilocaine. Sensory block onset time was 4.5 minutes (3.5-6.5 min.). Mean tourniquet time was 17.6 minutes (range, 7-27.5 min). Mean tourniquet pressure was 240 mmHg (range, 220-270 mm Hg). The mean VAS score for tourniquet pain was 3.8 (range, 2-10). No local or systemic side effects related to the IVRA were observed. The study showed that distal forearm IVRA using 10 ml of a solution containing 1.5 mg/kg prilocaine provides safe, rapid and effective anaesthesia for patients undergoing outpatient hand surgery.  相似文献   
10.
Objective: Trans-sphenoidal surgery is often combined with other approaches for the treatment of middle cranial base tumors. By combining a maxillotomy with trans-sphenoidal approach, significantly wider exposure to these regions is gained. However, endoscope-assisted techniques have also been used for sellar and parasellar and upper clival regions. Methods: An extended trans-sphenoidal approach was performed on 10 cadaver heads using the operating microscope and was repeated with a 0-degree endoscope. The mean horizontal and vertical distances were measured and pictured for each technique, and both distances were compared using a parametric paired Student's t-test. Results: The mean horizontal distances in the 10 specimens were 19.5 ± 1.8 mm by microscope and 27.5 ± 2.2 mm by endoscope, and the mean vertical distances were 25.8 ± 1.9 mm by the microscope and 34.5 ± 3.5 mm by the endoscope. Conclusion: The aim of this study was to quantify the amount of exposure obtained with an extended trans-sphenoidal approach and to compare both endoscopic and microscopic techniques. Using the endoscope in conjunction with the operating microscope may provide additional exposure and better access in skull base surgery.  相似文献   
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