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61.
Frances Rudnick Levin Judith M. Hess David A. Gorelick Nancy A. Kreiter Paul J. Fudala 《The American journal on addictions / American Academy of Psychiatrists in Alcoholism and Addictions》1993,2(2):109-115
The authors systematically evaluated the frequency patterns of cocaine use in 85 cocaine-dependent outpatients and found four patterns of use: continuous (27%), intermittent patterned (35%), intermittent nonpatterned (25%), and occasional (13%). Few subjects reported consistent cycling between binges and crashes. There were no significant differences in patterns of use associated with gender, race, educational level, route of administration, or recency of heroin use. Continuous users and occasional users were older than intermittent users. Because different contingencies may control patterned vs. nonpatterned cocaine use, pattern of use may have implications for treatment, even in individuals reporting similar amounts of cocaine use. 相似文献
62.
63.
64.
Peritoneal morphology in children treated by continuous ambulatory peritoneal dialysis 总被引:2,自引:0,他引:2
Fritz Schneble Klaus-Eugen Bonzel Rüdiger Waldherr Sebastian Bachmann Helga Roth Karl Schärer 《Pediatric nephrology (Berlin, Germany)》1992,6(6):542-546
Fifty peritoneal biopsies (PB) from 35 patients with end-stage renal disease, treated by continuous ambulatory peritoneal dialysis (CAPD) and aged 2 months to 18 years, were examined by light microscopy (n=50) and/or scanning electron microscopy. PB were performed during surgical procedures immediately before the start of, during, or after the cessation of CAPD treatment. PB from 15 children without renal disease undergoing laparatomy were examined similarly. Before the start of CAPD, a scarcity and shortening of the mesothelial microvilli was observed by scanning electron microscopy. During and after CAPD, variable alterations of mesothelium, interstitium and capillaries were found. The mesothelial layer was absent in all 5 PB obtained during episodes of active peritonitis. In patients treated by CAPD for longer than 6 months, mesothelial denudation was observed more frequently (6/11) than in children treated for shorter periods (1/7) (P<0.08). Fibrosis of the peritoneal membrane was present in about 50% of patients during or after the cessation of CAPD without impairment of peritoneal function. No correlation was found between the presence of fibrosis and the frequency of peritonitis or the duration of CAPD treatment. 相似文献
65.
M. V. Lareu C. Pestoni A. Carracedo M. Schürenkamp S. Rand B. Brinkmann 《International journal of legal medicine》1996,109(3):134-138
A total of 103 fragments in the STR D12S391 locus were sequenced. 24 different alleles were found which can be grouped into 12 allelic classes based on the total number of repeats. The structure of this compund STR consists of blocks of (AGAT) and (AGAC) repeats with a consensus structure (AGAT)8–l7 (AGAC)6–10 (AGAT)0–1. Whereas shorter alleles only have (AGAT) repeats, > 225 bp alleles are more complex, having two motifs (AGAT) and (AGAC). Population data showed that this to be a highly polymorphic STR with a heterozygosity of 0.9. This fact together with its simple structure make this STR very suitable for forensic and genetic purposes. 相似文献
66.
Monitoring left ventricular dilation in mice with PET. 总被引:3,自引:0,他引:3
Lars Stegger Klaus P Sch?fers Ulrich Fl?gel Lefteris Livieratos Sven Hermann Christoph Jacoby Petra Keul Edward M Conway Otmar Schober Jürgen Schrader Bodo Levkau Michael Sch?fers 《Journal of nuclear medicine》2005,46(9):1516-1521
Molecular imaging by small-animal PET is an important noninvasive means to phenotype transgenic mouse models in vivo. When investigating pathologies of the left ventricular (LV) myocardium, the serial assessment of LV volumes is important. By this, the presence of LV dilation as a sign of developing heart failure can be detected. Whereas PET is usually used to derive biochemical and molecular information, functional parameters such as ventricular volumes are generally measured using echocardiography or MRI. In this study, a novel method to monitor LV dilation in mice with PET is presented and evaluated using cardiac MRI. METHODS: A semiautomatic 3-dimensional algorithm was used to delineate the LV myocardial wall on static PET images depicting myocardial glucose metabolism ((18)F-FDG PET) for 20 mice: 10 wild-type and 10 genetically modified littermates designed to develop a dilative cardiomyopathy phenotype (cardiomyocyte-specific knockout of survivin). The volume enclosed by the 3-dimensional midmyocardial contour was calculated as a measure for LV volume for each mouse. Data were compared with ventricular volumes measured by MRI in the same animals. RESULTS: LV volumes obtained by PET and MRI correlated well (R = 0.89) for hearts with small and large left ventricles. In accordance with the hypothesis, the LV volumes were increased significantly for transgenic mice examined at an older age compared with those examined at a younger age (MRI: 160.5 +/- 25.7 microL vs. 114.7 +/- 15.2 microL [P = 0.012]; PET: 129.3 +/- 15.3 microL vs. 73.8 +/- 15.0 microL [P < 0.001], all values shown as mean +/- SD; for MRI, mean of end-diastolic and end-systolic volumes are given), whereas they did not for their wild-type littermates (MRI: 106.2 +/- 12.3 microL vs. 94.7 +/- 14.6 microL [P = 0.214]; PET: 82.6 +/- 20.9 microL vs. 65.0 +/- 16.9 microL [P = 0.185]). CONCLUSION: Evaluation and quantitation of LV dilation in both control and cardiomyopathic mice can be reliably and serially performed using small-animal PET and (18)F-FDG, yielding useful functional information in addition to metabolic data. 相似文献
67.
Soft tissue sarcomas (STS) represent a rare entity of all malignant tumors (1%). Thus, an in-depth understanding of multidisciplinary treatment strategies may not be sufficiently present at all operative units. Consecutively, optimal diagnostic and therapeutical pathways may not be applied. Magnetic resonance imaging (MRI) is the procedure of choice in diagnosing STS. Biopsies should be performed in specialized centers. Identification of cytogenetic factors has become more important for the typing and prognosis of STS. Management of STS should employ multimodal treatment concepts (Oncology, Radiotherapy, Surgical Oncology). The decision on whether radiotherapy, chemotherapy or another option is indicated should be taken by an interdisciplinary tumor board, which also determines the sequence of treatment in relation to resection. To obtain sufficient information from histopathologic examination of the resected tumor, a clear and distinct definition of critical margins and topography by the surgeon is essential. Following these concepts, optimal local tumor control associated with resections preserving function and limbs is achieved without impairment of overall prognosis. Tumor resection alone, without previous evaluation and where appropriate adopting multimodal treatment strategies, no longer meets modern standards. After primary treatment is complete, patients have to be enrolled in a standardized follow-up program. 相似文献
68.
Anterior Cruciate Ligament Reconstruction:
State of the Art 总被引:2,自引:0,他引:2
Abstract The rupture of the Anterior cruciate ligament (ACL)
belongs to the most common ligament injuries of the
human knee joint. ACL rupture results in an increased
anterior translation and internal rotation of the tibia.
Untreated knee instability causes a disintegration of
the roll and sliding movement and a high incidence of
secondary meniscus and chondral damages with consecutive
or advanced arthritic changes.
For deciding on a conservative or operative therapy, it is
necessary to develop a high-risk profile. Elderly, inactive
patients without instability symptoms can be treated
conservatively; younger, active people and complex
ligament injuries should receive an ACL replacement.
The goal is to eliminate instability by maintaining the
physiological kinematics of the knee.
Anterior cruciate ligament may be reconstructed
arthroscopically assisted by autologous tendons. Predominantly,
hamstring- and bone-patellar-tendon
grafts are used. No significant differences in knee laxity,
clinically and functionally, were observed between
both grafts. Various reconstruction techniques, single-
or double-bundle techniques, were described. Successful
replacement depends on a correct tunnel placement
and reconstruction of the physiological band
tension, a sufficient mechanical stability of fixation, an
impingement-free range of motion and an adequate
rehabilitation.
A high degree of patient satisfaction in clinical and
functional outcome could be evaluated. 相似文献
70.
Increase in the degree of phosphorylation of circulating fibrinogen under thrombolytic therapy with urokinase 总被引:2,自引:0,他引:2
Human fibrinogen is phosphorylated in vivo to an equal extent at two positions, one at Ser 3 located on fibrinopeptide A, the other at Ser 345 of the A alpha-chain. As has been shown previously, the degree of phosphorylation of the circulating fibrinogen pool can be determined in vitro from the ratio between the HPLC peaks formed by phosphorylated and non-phosphorylated fibrinopeptide A which has been cleaved from plasma fibrinogen by thrombin or reptilase. Plasma samples were obtained from patients with venous thrombosis undergoing fibrinolytic therapy with urokinase (n = 8). The degree of phosphorylation increased from about 35% before treatment to values between 50% and 70% within 48 hours. It remained at these high levels as long as urokinase was administered and declined slowly thereafter. This behaviour of the degree of phosphorylation of fibrinogen is explained by a model which assumes that fibrinogen is secreted in the phosphorylated form and then dephosphorylated in the circulation by an up to now unidentified phosphatase by first order kinetics. When this system is in steady state, the degree of phosphorylation is about 25% under normal conditions. If the elimination rate of fibrinogen is greatly enhanced by fibrinogenolysis the system will approach a new steady state with a higher degree of phosphorylation, the magnitude of which will depend on the new ratio of dephosphorylation and elimination. 相似文献