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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 objective was to demonstrate bioequivalence between s.c. and i.m. administration of Humegon (FSH/LH ratio 1:1) and Normegon (FSH/LH ratio 3:1). In two randomized, single-centre, cross-over studies, 18 healthy volunteers on each formulation were assigned to one of the two administration sequences. Subjects were given single doses of one of the above gonadotrophins after endogenous gonadotrophin production had first been suppressed using high-dose oral contraceptive. Subsequently, rate (Cmax, tmax) and extent (AUC) of absorption of follicle stimulating hormone (FSH) and luteinizing hormone (LH) were determined for 14 days. For Cmax and AUC, analysis of variance (ANOVA) was performed on log-transformed data and for tmax ANOVA was performed on ranks. Intramuscular and s.c. injections of Humegon were bioequivalent with respect to the main pharmacokinetic parameters, being AUC and Cmax of FSH absorption. Intramuscular and s.c. injections of Normegon were bioequivalent with respect to the AUC of FSH and not bioequivalent with respect to the Cmax of FSH. For tmax of FSH as well as for most LH variables of both preparations, bioequivalence could not be proven due to the high intra- and interindividual variability and/or concentrations being close to the detection limit. Thus, the main pharmacokinetic FSH variables after i.m. and s.c. administration of Humegon and Normegon were bioequivalent.   相似文献   
4.
This study investigated outpatients' satisfaction with therapists, as determined by their perceptions of therapists' behaviors and characteristics, and related patient satisfaction to measures of psychotherapy outcome derived from patients themselves, therapists, and an independent rater. After discharge, 138 demographically and diagnostically heterogeneous patients who had been in psychodynamically oriented psychotherapy returned mailed questionnaires. Therapist characteristics and behaviors such as being likeable, accepting, encouraging, and respectful, helping patients to understand themselves better, and not being "too quiet," as well as overall ratings of satisfaction with therapists, were significantly correlated with patients' ratings of improvement and of help received and with therapists' ratings of outcome.  相似文献   
5.
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   
6.
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   
7.
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   
8.

Essentials

  • Risk of venous thrombosis (VT) related to valve thickness and valvular reflux in unknown.
  • Venous valves and reflux were measured by ultrasonography in cases and controls aged 70+.
  • Risk of VT was associated with increased valve thickness and valvular reflux >1second.
  • Thickening of valves is a generic process: there was no difference between right and left legs.

Summary

Background

Increasing age is the strongest risk factor for venous thrombosis (VT). Increasing age has been related to a thickening of the venous valves and a decreased valvular function. The association between valve thickness and the risk of VT is not known.

Objectives

To assess the association between increased valve thickness and valve closure time (VCT) and the risk of VT.

Methods

Analyses were performed in the BATAVIA study, including 70 cases aged 70 + with a first VT and 96 controls. We performed an ultrasound examination of the valves in the popliteal veins. The valves were imaged with a 9 MHz linear probe using B‐mode ultrasonography. VCT was measured as an indicator for valve function using an automatic inflatable cuff. To estimate the risk of VT, valve thickness was dichotomized at the 90th percentile as measured in controls and VCT was dichotomized at 1 s.

Results

Mean valve thickness of controls was similar in the left (0.36 mm, 95% CI 0.34–0.37) and right (0.36 mm, 95% CI 0.35–0.38) leg. In 45 cases a valve was observed in the contralateral leg with a mean valve thickness of 0.39 mm (95% CI 0.36–0.42). Cases had an increased valve thickness compared with controls: mean difference 0.028 mm (95%CI 0.001–0.055). Valve thickness > 90th percentile increased the risk of VT 2.9‐fold. Mean VCT in controls was 0.38 s, in contralateral leg of cases 0.58 s. VCT > 1 s increased the risk of VT 2.8‐fold (95% CI 0.8–10.4).

Conclusions

Risk of VT was associated with increased valve thickness and valvular reflux of > 1 s.  相似文献   
9.
Mesial temporal sclerosis (MTS) is the most frequent cause of drug resistant symptomatic partial epilepsy. The mechanism and genetic background of this unique pathology are not well understood. Aquaporins (AQP) are regulators of water homeostasis in the brain and are expressed in the human hippocampus. We explored the role of AQP genes in the pathogenetic mechanisms of MTS through an evaluation of gene expression in surgically removed human brain tissue. We analyzed AQP1 and 4 mRNA levels by quantitative real-time polymerase chain reaction and normalized to ABL and cyclophilin genes, followed by immunohistochemistry for AQP4. Relative expressions were calculated according to the delta Ct method and the results were compared using the Mann-Whitney U test. Brain specimens of 23 patients with epilepsy who had undergone surgery for MTS and seven control autopsy specimens were investigated. Clinical findings were concordant with previous studies and 61% of the patients were seizure-free in the postoperative period. AQP1 and 4 gene expression levels did not differ between MTS patients and control groups. Immunofluorescence analysis of AQP4 supported the expression results, showing no difference. Previous studies have reported contradictory results about the expression levels of AQP in MTS. To our knowledge, only one study has suggested upregulation whereas the other indicated downregulation of perivascular AQP4. Our study did not support these findings and may rule out the involvement of AQP in human MTS.  相似文献   
10.
目的 分析延边地区建立肺结核归口转诊模式对肺结核病人的转诊到位率的影响,探讨提高转诊到位率的方法。方法 对全州8个县(市)医院、中医医院、中心卫生院、大型厂矿企事业单位职工医院的执法检查考核资料进行评价。结果 1.建立归口转诊模式前期转诊率为48.3%,转诊到位率为29.0%,后期转诊率为89.0%,转诊到位率为72.4%,有明显提高;2.前期年平均涂阳病人新登记率为13.36/10万,后期为17.86/10万,实施归口转诊模式前期与实施后期的指标有显著性差异(P<0.01)。结论 延边地区实施的肺结核病人归口转诊模式,对提高肺结核病的转诊到位率十分有效,应不断完善并深入推广。  相似文献   
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