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71.
The quantitative determination of coumarins, flavonoids and chlorogenic acid in the leaves and underground parts of Scopolia carniolica Jacq., S. lurida Dun. and S. sinensis Hemsl. using the RP-HPLC method has been described.  相似文献   
72.
Toluene is a major component of numerous commercial organic solvent formulations. It is often listed among the chemicals capable of producing the organic solvent syndrome and a neurobehavioral hypersensitivity condition. The hypersensitivity condition (continued long-term intensification of some behavioral reactions in response to pharmacological or environmental stressors) is usually associated with the increased tonus of the functional dopaminergic system. The aim of our current research was to determine whether, under conditions of inhalation exposure, toluene can produce long-term behavioral changes or modify the intensity of the behavioral response to apomorphine, a dopaminergic receptor agonist. In our experiment, male rats were exposed to 25, 100 and 250 ppm toluene for 4 weeks (5 days/week, 6h/day). The following behaviors were tested: finding water in a radial maze; open field motor activity, acquiring the conditional response of passive avoidance; sensitivity to a thermal pain stimulus (hot plate test) and changes in this sensitivity caused by stress; and acquiring the conditional response of two-directional active avoidance. The behavioral response to apomorphine, i.e. the increased spontaneous locomotor activity, was assessed on day 10 after the termination of the exposure in the rotary drum test. In the behavioral experiment, significant differences between groups were recorded only for the hot plate test; in the 100 and 250 ppm rats, electric-shock-related anxiety response was stronger than in the control group. In the experiment using pharmacological provocation, the behavioral response to apomorphine in the rats exposed to 100 ppm or 250 ppm toluene was significantly lower. Our results indicate that low concentrations of toluene may produce long-term behavioral changes in rats. However, these changes seem to be linked with reduced rather than increased functional tonus of the dopaminergic system.  相似文献   
73.
BACKGROUND: Two clinical types of leptomeningeal metastases from solid tumors are observed: local and disseminated. The former (meningeal carcinomatosis) consists in nodular infiltration of leptomeninges, while the latter (carcinomatous meningitis)--in tumor cells free floating in the cerebrospinal fluid and adhering as a monolayer to the surface of neural structures. Despite the same etiology, the two types of metastasis differ in their clinical manifestation and prognosis. Meningeal carcinomatosis is more frequently diagnosed nowadays due to advances in neuroimaging techniques and the long survival of breast cancer patients. Patients with local, nodular infiltration of leptomeninges may survive many years without symptoms of the disease. On the other hand, carcinomatous meningitis, with its usually violent course and short survival, has become a major problem for oncologists and neurologists because of limited efficacy and considerable toxicity of the treatment. AIMS: The purpose of this article is to review the current knowledge about carcinomatous meningitis in breast cancer patients, taking into account pathophysiology, clinical symptoms, diagnosis, treatment and prognosis. The second aim was to present the authors' experience with the treatment of breast cancer patients suffering from carcinomatous meningitis. MATERIAL AND METHODS: 37 patients with breast cancer and carcinomatous meningitis were treated in the Oncology Center, Warsaw, in the years 2000-2002. Their mean age was 51. The diagnosis was based on results of neurological examination, MRI scan, and the presence of neoplastic cells in the cerebrospinal fluid. In a majority of cases combined treatment was applied, including intrathecal administration of cytostatics, intravenous systemic chemotherapy and radiotherapy. RESULTS: The observation period ranged from 2 to 33 months. A response to the treatment was achieved in 76% of the patients. Their median overall survival was 19 weeks, mean 18 weeks. Seven patients (19%) survived for over 6 months. CONCLUSIONS: The ever-growing incidence of carcinomatous meningitis in the course of breast cancer has become a serious clinical problem for neurologists and oncologists. Treatment results are disappointing, although the combined modality treatment appears to be the best option. New pharmacological approaches to the treatment of meningeal malignancy are required to improve the outcome of patients with carcinomatous meningitis.  相似文献   
74.
The majority of antidepressants undergo the oxidative biotransformation catalysed by cytochrome P-450, particularly by izoenzyme CYP2D6, whose activity is genetically determined. In many cases poor tolerance of antidepressants depends on CYP2D6 activity. The aim of the study was the evaluation of the relationship between the CYP2Dg genotype and the occurrence of side effects during antidepressive pharmacotherapy.  相似文献   
75.
Despite the significant progress in the treatment of AML during the last 5-10 years, 20-40% of patients still do not achieve remission with standard induction therapy. In addition, 50-70% of patients in CR are likely to relapse. A major limitation of successful AML therapy is intrinsic or acquired drug resistance. Several pharmacological inhibitors of mechanisms inducing chemoresistance in leukemic cells have been investigated. New cytotoxic drugs, agents with novel mechanisms of action, and new treatment strategies are currently being investigated. The management of refractory or relapsed AML patients is reviewed in this study.  相似文献   
76.
The aim of the study was establishing which parameters play a significant prognostic role in acute haemorrhagic stroke in its acute phases (during 30 days from stroke onset). The material included 110 patients with haemorrhagic stroke (HS) treated in the years 1997-1999 at the II Neurology Department, Institute of Psychiatry and Neurology in Warsaw or at the Neurology Department, Hospital in Pi?a. The analysis of risk factors, fitness before stroke and on the first day of the disease was based on history data. On the first day of the disease the assessment included state of consciousness, brain stem signs, vomiting, stroke type on the basis of clinical condition (according to Oxford classification, OCSP), blood pressure, body temperature measurements, intensity of neurological signs according to Scandinavian scale (SSS). In the blood glucose level, fibrinogen, leucocyte count and ESR were determined. In the first week consciousness state, blood pressure and miction were checked repeatedly. It was found that serious consciousness disturbances, stroke type TACS, POCS and severe not classified stroke, presence of brain stem involvement, low SSS score, high body temperature, high leucocyte count and glucose level were more frequent in patients who died within 30 days after stroke onset. Prognostically important were also instability of blood pressure and urinary incontinence in the first week. All clinical observation and laboratory analyses of prognostic importance in the acute phase of HS can be done in typical hospital settings.  相似文献   
77.
On the grounds of Lithuanian and Russian archival materials unpublished so far, the paper presents the professional activity and psychiatric views of Klemens Maleszewski (1798-1873), who was the head of Vilnius's Asylum in 1837-1864. The time of 50s and 60s of the 19th century was a period of increasing attention about metallotherapy and electrotherapy. Above all, these methods were used in the treatment of cholera. Maleszewski conducted researches on the use of galvanic current and metallotherapy not only in cholera treatment, but also in the treatment of psychiatric disorders. He implemented successful electroshock therapy in a 35-year-old catatonic patient in 1861.  相似文献   
78.
79.
Ischemia-reperfusion injury is often responsible for delayed graft function after transplantation. Trimetazidine (TMZ) is an antioxidant agent used to protect grafts from ischemia-reperfusion injury. The aim of the study was to examine the effect of TMZ on nucleotide profile in rat kidney with ischemia-reperfusion injury. The study was carried out on Wistar rats divided into two groups: animals treated with TMZ and control group receiving placebo. TMZ 10mg/kg/day was administrated for 30 days. Concentrations of adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP), adenosine (Ado), guanosine triphosphate (GTP), guanosine diphosphate (GDP), guanosine monophosphate (GMP), guanosine (Guo), inosine monophosphate (IMP), inosine (Ino), hypoxanthine (Hyp), xanthine (Xan), uric acid (UA), uridine (Urd), nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP) were determined in kidney tissues after ischemia-reperfusion using HPLC. The total adenine nucleotide concentration (TAN) and adenylate energy charge (AEC) were also determined. Moreover the kidneys were evaluated histologically. Tissue concentrations of ATP, ADP, AMP, TAN and AEC were significantly increased in kidneys from rats treated with TMZ in comparison with rats receiving placebo. Concentrations of products of nucleotide degradation: inosine (Ino), guanosine (Guo) and uridine (Urd), as well as oxypurines: Hyp and Xan, were significantly decreased in rats treated with trimetazidine. Moreover, significantly less pronounced acute tubular necrosis was observed in kidneys of rats treated with TMZ. These results suggest that trimetazidine protects against dephosphorylation of nucleotides and ischemic damage.  相似文献   
80.
Summary Model selection methods have shown to be useful in the process of econometric modelling. The paper studies robust Akaike–Schwarz type information criteria of model choice within the Cox model. The criteria are based on a smooth modification of the partial likelihood function. Apart from asymptotic results, a Monte Carlo study is presented, which shows the finite sample behaviour of the procedure under discrepancies from the Cox model. Analysis of a real unemployment data case is also included.  相似文献   
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