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91.
76 endometrioid adenocarcinomas of the uterine body were studied. Expression of the above markers is of essential value together with metastatic involvement of regional lymph nodes, stage of the disease and pathogenetic variant for determining prognosis of carcinoma aggressiveness and disease outcome. Positive hormonal-receptor status of the tumor is characterized by well-differentiated tumor cells, small depth of invasion, rare metastases to regional lymph nodes and higher survival (5 year--81%) of patients comparing with cases where ER and PR were not determined (53%). On the contrary, overexpression of oncoprotein HER-2 and Ki-67 higher than median (42%) was associated with high tumor aggression resulting finally in a significant fall in the survival (from 75% to 58% and from 79% to 60%, respectively). Combination of HER-2 overexpression with a high level of Ki-67 is particularly unfavourable (5-year survival--43%).  相似文献   
92.
The inhibitory activity of different components from Candida albicans membrane protoplasts against clotrimazole and eberconazole was studied. The phospholipid fraction had the most inhibitory activity and the antimycotic activity of eberconazole was more affected than that of clotrimazole.  相似文献   
93.
Summary LL-D491941 is a new cytotoxic antibiotic selected for clinical phase I study because of its impressive pre-clinical anti-tumour activity and its low toxicity profile in experimental animals. A total of 15 patients were treated in centres in Glasgow and Amsterdam at doses ranging from 0.25 to 4 mg/m2. One minor response was noted in a patient with colonic carcinoma. The study was suspended following the discovery of unexpected cardiotoxicity. As this toxicity was not consistent with the standard (EORTC) European Organisation for Research and Treatment of Cancer toxicology profile, we chose to investigate the pharmacokinetics of LL-D491941 in mice and humans in more detail to try to explain this phenomenon. A major difference in plasma protein binding was discovered between mice and patients, with a suggestion of non-linear kinetics being noted at higher doses in humans. It is likely that these differences in drug handling account for the unexpected and serious toxicity encountered in this trial.  相似文献   
94.
Summary N-pentyl-sparsomycin (PSm) is a lipophilic analogue of sparsomycin (Sm), which is a well known inhibitor of protein synthesis. This compound was selected for preclinical pharmacokinetic studies because of its high in vitro and in vivo antitumor activity. In this study in which the drug was evaluated in beagle dogs under anaesthesia, the drug concentrations in plasma, urine and bile samples were determined using high performance liquid chromatography (HPLC). Plasma protein binding was approximately 54%. The mean t1/2 was 0.2 hours (12 minutes) and t1/2 was 0.75 ± 0.1 hours (45 ± 6 minutes). During continuous infusions up to 5.25 hours, the steady state was reached in 3 out of 6 experiments, suggesting that in some cases the real t1/2 was longer than measured. PSm was actively reabsorbed from the renal tubuli. This process was saturable at the higher doses. Tubular reabsorption played only a minor role in pharmacokinetics as most of the drug (67%) was eliminated by the non-renal clearance. The non-renal clearance was saturable at higher doses of PSm and was the reason for non-linearity of pharmacokinetics.  相似文献   
95.
Breast cancer is the most common malignancy in women, accounting for about 18% of female cancers, and over half a million new cases are diagnosed worldwide each year. Its incidence increases with age and is currently rising. Although the increased availability of screening programs has allowed earlier detection and treatment of primary breast cancers, many patients relapse with metastases after apparently successful treatment of their primary tumor and over 15,000 women in the UK and about 50,000 in the USA die from advanced disease each year. The natural course of breast cancer is very variable even after the development of metastases, and depends on a variety of tumor characteristics and prognostic factors. This is reflected in the large number of treatments currently employed. However, despite this wide choice and considerable research over the years, treatment of metastatic breast cancer (MBC) prolongs average survival times only slightly. Current therapy is aimed at achieving a balance between producing maximal tumor shrinkage to produce the most effective possible palliation of symptoms, and minimizing adverse effects. Anticancer chemotherapy is the preferred option in patients who do not respond to hormones, those with hormone-independent tumors, those with aggressive breast cancer subtypes. A variety of anticancer chemotherapy regimens, using both single and combined agents, have been shown to be effective in achieving tumor regression in MBC. Anthracyclines (doxorubicin, epirubicin) are the most active of the established monotherapies, typically producing response rates of 50-60% during initial (first-line) treatment for metastatic disease, but being effective in fewer than 25% of patients requiring second-line therapy. The drawbacks of anthracyclines include dose-limiting cumulative cardiotoxicity and the development of resistant tumor clones after the use of anthracyclines for adjuvant or first-line therapy, especially if subsequent courses are required within a year. The success of these established chemotherapeutic agents depends greatly on the number and location of metastatic sites. Lymph node and soft tissue secondaries tend to respond well, while visceral metastases (especially in the liver) carry a particularly poor prognosis despite treatment. The outlook for patients with metastases involving more than two organ systems is also bleak. Although some patients can live for years with metastatic disease, the average survival time in patients with MBC is 18-24 months, while in those with liver metastases, life expectancy averages only 6 months. High-dose anticancer chemotherapy with granulocyte-colony stimulating factor (G-CSF) or autologous bone marrow transplantation has allowed the dose intensity of anthracyclines to be increased, and has improved the response rate to about 70% in selected patients with MBC. However, this approach has not been proven to improve survival, involves the risk of greater toxicity and drug-related mortality, and patients with reduced clearance of anthracyclines due to hepatic dysfunction from liver metastases may not be suitable candidates. A number of new anticancer agents have also recently been introduced in an attempt to improve on the performance and avoid the tolerability problems associated with anthracyclines. Among these, antitubulin agents (taxoids and vinorelbine) have shown highly promising activity in MBC. This paper reviews the preclinical, phase I and phase II data for one taxoid, docetaxel. Docetaxel (Taxotere) belongs to the taxoid class of cytotoxic agents, the development of which began more than 20 years ago. In 1971, paclitaxel (Taxol) was identified as the active compound of the crude extract of the bark of the Pacific Yew tree Taxus brevifolia. However, at that time the development of paclitaxel was hampered because of the limited source of the drug and difficulties with isolation, extraction and formulation. The second active taxoid, docetaxel, was isolated by Potier et al. in 1986. Docetaxel is prepared from a non-cytotoxic precursor, extracted from the needles of the European Yew tree Taxus baccata, that is condensed with a chemically-synthesized side-chain. As the docetaxel precursor is freely available because of the regenerating capacity of the needles the development of docetaxel has thus been rapid.  相似文献   
96.
97.
  • (i) The objective was to determine the range of bone levels of cefuroxime and flucloxacillin achieved after one intravenous (IV) administration of different dosages of cefuroxime and flucloxacillin.
  • (ii) Six groups of five patients participated in the study. The first three groups (A–C) received respectively 1500 mg, 1000 mg, and 500 mg cefuroxime intravenously and the second three groups (D–F) received 2000 mg, 1500 mg, and 1000 mg flucloxacillin intravenously.
  • (iii) Parenteral administration of cefuroxime and flucloxacillin resulted in measurable bone concentrations in all patients.
  • (iv) Large inter-individual variation in bone concentration was observed.
  • (v) The bone concentrations of IV cefuroxime were higher (1500 mg, p = 0.0057; 1000 mg, p = 0.0260) than those of flucloxacillin. The bone concentrations of cefuroxime and flucloxacillin were dose dependent.
  相似文献   
98.
A four years-old boy with Xanthogranulomatous pyelonephritis was surgically treated at the Pediatric Surgery Unit of the Santa Casa de Misericórdia of Maceió. Comments are made upon pathology, pre-operative diagnostic difficulties, differential diagnosis, and the rare occurrence in children.  相似文献   
99.
The aim of this study was to follow the fate of dietary nitrogen to assess the postprandial utilization of purified milk protein and to determine the acute influence of energy nutrients. For this purpose, a [15N]-labeling dietary protein approach was used. Twenty-five subjects swallowed an ileal tube and ingested [15 N]-milk protein alone or supplemented with either milk fat or sucrose. The absorption and postprandial deamination of dietary protein was monitored for 8 h. Sucrose delayed the absorption of protein longer than fat, but the ileal digestibility did not differ among groups (94.5-94.8%). Sucrose, but not fat, significantly reduced the postprandial transfer of [15N]-milk nitrogen to urea. Consequently, the net postprandial protein utilization (NPPU) of milk protein calculated 8 h after meal ingestion was 80% when ingested either alone or supplemented with fat and was significantly greater with sucrose (NPPU = 85%). This study shows that energy nutrients do not affect the nitrogen absorption but modify the metabolic utilization of dietary protein in the phase of nitrogen gain. Our method provides information concerning the deamination kinetics of dietary amino acids and further allows the detection of differences of dietary protein utilization in acute conditions. The diet composition should be carefully considered, and protein quality must be determined under optimal conditions of utilization.  相似文献   
100.
Systemic administration of the mitochondrial toxin 3-nitropropionic acid (3-NP) to rats results in selective striatal lesions and serves as an experimental model of Huntington's disease (HD). However, the effects of the 3-NP treatment are unpredictable and result in lesions of variable severity. The present study was aimed at further characterizing the variability of the striatal lesions induced by systemic administration of 3-NP using osmotic pumps. Hematoxylin-eosin (HE) and Nissl stains as well as immunohistochemical labelling of astrocytes and striatal neurones were performed to analyse the neurotoxic effects of 3-NP. In general, chronic systemic administration of 3-NP resulted in obvious bilateral striatal lesions, which ranged from mild to severe, together with a subtle, but detectable behavioural lesion. Severe type lesions showed marked neuronal loss and an increased expression of glial fibrillary acidic protein (GFAP) in astrocytes surrounding the lesion area, whereas in the core of the lesion GFAP-immunoreactivity was absent. The mild type lesion was characterized by a substantial loss of striatal neurones and an increased expression of GFAP-positive astrocytes throughout the lesion. In a number of 3-NP-treated animals, neither type of lesion was observed, although these animals demonstrated behavioural changes in the paw test compared to controls. In the striatum of these tested 3-NP-treated animals, compromised rk' neurones were detected, suggestive of subtle and early 3-NP-induced neuronal injury. Similar dark neurones were also detected in mild and severe lesions and were immunocytochemically characterized as gamma-aminobutyric acid (GABA) and substance P containing spiny neurones, which belong to the neuronal population that is affected in early HD. These results indicate that systemic administration of 3-NP to rats may result in a spectrum of striatal pathology of which the morphology of the mild type lesion resembles the characteristic HD neuropathology most closely.  相似文献   
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