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61.
Aim:   Two 21-day gemcitabine–carboplatin schedules were evaluated in patients with advanced non-small cell lung cancer in order to assess the effect of timing of the carboplatin dose on toxicity and efficacy.
Methods:   Patients were randomized to gemcitabine (1000 mg/m2 on days 1 and 8 of a 21-day cycle) and carboplatin (AUC 5, on day 1) (Carbo d1 arm) or the same gemcitabine schedule with carboplatin given on day 8 (Carbo d8 arm). Twenty patients with Stage IIIB or IV non-small-cell lung cancer were enrolled in each arm.
Results:   The achieved dose intensities of both gemcitabine and carboplatin were significantly higher in the Carbo d1 arm. The total rates of grade 3 or 4 hematological and non-hematological toxicities (any toxicity, any cycle) were 80% and 65%, respectively, with no significant differences between the two arms. Nine patients in the Carbo d1 arm, but only one patient in the Carbo d8 arm, required a platelet transfusion. There were 10 partial responses (four Carbo d1 arm, six Carbo d8 arm), giving an overall response rate of 25% (95% CI 13–41%).
Conclusion:   Administration of carboplatin on day 8 of this regimen confers no clear advantage compared with day 1 carboplatin, with similar toxicity but lower dose intensity. A formula for the prediction of thrombocytopenia is proposed.  相似文献   
62.
We evaluated the frequency of congenital chromosomal aberrations in a sample of 305 couples included in an intracytoplasmic sperm injection (ICSI) programme. Twenty individuals (3.3%) with congenital chromosomal abnormalities could be identified. The following types of abnormalities were observed: reciprocal translocations (n = 7), Robertsonian translocations (n = 3), inversions (n = 3), other structural aberrations (n = 4) and sex chromosome aberrations (n = 3). The rate of chromosomally abnormal males (10/305, 3.3%) lay within the expected range for patients with reduced semen quality. Surprisingly, 50% (10/20) of all abnormal karyotypes were contributed by the female partner of ICSI patients. These data confirm the higher incidence of chromosomal aberrations in infertile populations as compared with the baseline population risk. Additionally, the data imply that in some cases of male factor infertility a hidden female chromosomal factor may be present, which cannot be identified by standard clinical evaluation. In conclusion, we recommend chromosomal analysis in both partners of couples undergoing ICSI treatment.   相似文献   
63.
Antifungal activity of natural products is being studied widely. Saponins are known to be antifungal and antibacterial. We have isolated eight steroid saponins from Tribulus terrestris L. , namely TTS-8, TTS-9, TTS-10, TTS-11, TTS-12, TTS-13, TTS-14 and TTS-15. TTS-12 and TTS-15 were identified as tigogenin-3-O-β-D-xylopyranosyl(1→ 2)-[-β-D-xylopyranosyl( 1 → 3 ) 3-β- D-glucopyranosyl ( 1 → 4 )- 1- α-L-rhamnopyranosyl ( 1 → 2 ) 3-β-D-galactopyranoside and tigogenin-3-O-β-D-glucopyranpyranosyl(1→2)-[-β-D-xylopyranosyl(1→ 3)3-β-D-glucopyranosyl(1→4)-β-D-galactopyranoside, respectively. The in vitro antifungal activities of the eight saponins against six fluconazole-resistant yeasts, Candida albicans, Candida glabrata, Candida para psilosis , Candida tropicalis , Candida krusei , and Cryptococcus neo f ormans were studied using microbroth dilution assay. The results showed that TTS-12 and TTS-15 were very effective against several pathogenic candidal species and C. neoformans in vitro. It is noteworthy that TTS-12 and TTS-15 were very active against fluconazole-resistant C. albicans (MIC80 = 4.4, 9.4 mg/ml), C. neoformans (MIC80 =10.7, 18.7 mg/ml) and inherently resistant C. krusei (MIC80 =8.8, 18.4 mg/ml). So in vivo activity of TTS-12 in a vaginal infection model with fluconazole-resistant C. albicans was studied in particular. Our studies revealed TTS-12 also showed in vivo activities against fluconazole-resistant yeasts. In conclusion, steroid saponins TTS-12 and TTS-15 from Tribulus terrestris L. have significant in vitro antifungal activity against fluconazole-resistant fungi, especially TTS-12 also showed in vivo activity against fluconazole-resistant C. albicans.  相似文献   
64.
65.
A total of 326 Afghan children aged between 6 months and 5 years with uncomplicated nondysenteric diarrhea for the previous 24 h to 5 days were treated at home by their mothers with either wheat-salt solution (WSS) or World Health Organization recommended glucose-oral rehydration salts (G-ORS). For 7 consecutive days the children were examined in the household and the mothers interviewed to assess the progress, feeding practices, and perception of treatment efficacy. Children treated with WSS recovered significantly earlier; the mean duration on treatment was 4.0 days (SD 1.7 days) on WSS compared to 6.4 days (SD 1.7 days) on G-ORS. By the second day of treatment, significantly more mothers using WSS (56%) reported that their children had formed stools versus 11 % of their G-ORS counterparts; the mean stool frequency after 2 days was also significantly reduced; 3 stools day−1 (SD 2.1) on WSS versus 5 (SD 2.9) on G-ORS. The cereal-based solution was not confused with normal food and led to better feeding patterns. By day 2, 74% of the mothers using WSS had resumed their normal feeding frequencies as opposed to 33% of G-ORS mothers. On recovery the WSS group had gained significantly more weight; the WSS group gained 169 g (SD 142 g) while the G-ORS group lost 150g (SD 174 g). This study suggests by subjective and objective measures that WSS could be considered as an effective home fluid for the first-line treatment of diarrhea.  相似文献   
66.
Granulocytic sarcoma (chloroma): CT manifestations   总被引:2,自引:0,他引:2  
Nests of granulocytic tumor cells in patients who have myelogenous leukemia are termed chloromas. Eight cases of chloroma seen on CT were reviewed. Lymph nodes, subcutaneous tissues, peritoneum, pleural space, pelvis, and portal hepatis were involved. Two patients exhibited chloroma as the sole manifestation of their disease during bone marrow remission. The extracranial appearance of chloroma on CT is that of small, nonenhancing, nodular densities that resemble lymphoma. Cranial involvement is characteristically in the orbit. The central nervous system appearance is variable, however, and high attenuation masses may occur that mimic lymphoma, hematoma, and metastatic neuroblastoma. The recognition of these lesions is important, since radiation, not chemotherapy, is often the preferred treatment for localized chloroma.  相似文献   
67.
Ishii  H; Salem  HH; Bell  CE; Laposata  EA; Majerus  PW 《Blood》1986,67(2):362-365
Protein C activation by thrombin is significantly accelerated by the endothelial cell cofactor, thrombomodulin. In this study, we have developed a radioimmunoassay for thrombomodulin and have measured the cofactor content in several human tissues. The assay method detects as little as 2 ng of thrombomodulin. The highest thrombomodulin content was found in lung and placenta, but the antigen was also detected in spleen, pancreas, liver, kidney, skin, heart, and aorta. Unexpectedly, thrombomodulin was absent from brain. Extracts from cerebral cortex, cerebellum, centrum semiovale, midbrain, basal ganglia, pons, and medulla were devoid of thrombomodulin. In contrast, thrombomodulin antigen is present in extracerebral intracranial vessels, including basilar and internal carotid arteries and choroid plexus, as well as in endothelium of the pia-arachnoid.  相似文献   
68.
In several families with non-specific X-linked mental retardation (XLMR) linkage analyses have assigned the underlying gene defect to the pericentromeric region of the X chromosome, but none of these genes have been isolated so far. Here, we report on the cloning and characterization of a novel gene, DXS6673E, that maps to Xq13.1, is subject to X-inactivation and is disrupted in the 5' untranslated region by a balanced X;13 translocation in a mentally retarded female. The DXS6673E gene is highly conserved among vertebrates and its expression is most abundant in brain. It encodes a hydrophilic protein of 1358 amino acids (aa) that does not show sequence homology to other known proteins. A segment of this protein consisting of neutral and hydrophobic aa with a proline residue in every second position may represent a transmembrane domain. Almost complete sequence identity was found between the 3' end of the DXS6673E gene and two expressed sequence tags (ESTs) and between the 5' end of the DXS6673E gene and a third EST. Moreover, weaker sequence similarity was observed between coding regions and two other ESTs.   相似文献   
69.
Prelingual non-syndromic (isolated) deafness is the most frequent hereditary sensory defect. In >80% of the cases, the mode of transmission is autosomal recessive. To date, 14 loci have been identified for the recessive forms (DFNB loci). For two of them, DFNB1 and DFNB2, the genes responsible have been characterized; they encode connexin 26 and myosin VIIA, respectively. In order to evaluate the extent to which the connexin 26 gene (Cx26) contributes to prelingual deafness, we searched for mutations in this gene in 65 affected Caucasian families originating from various countries, mainly tunisia, France, New Zealand and the UK. Six of these families are consanguineous, and deafness was shown to be linked to the DFNB1 locus, 10 are small non consanguineous families in which the segregation of the trait has been found to be compatible with the involvement of DFNB1, and in the remaining 49 families no linkage analysis has been performed. A total of 62 mutant alleles in 39 families were identified. Therefore, mutations in Cx26 represent a major cause of recessively inherited prelingual deafness since according to the present results they would underlie approximately half of the cases. In addition, one specific mutation, 30delG, accounts for the majority (approximately 70%) of the Cx26 mutant alleles. It is therefore one of the most frequent disease mutations so far identified. Several lines of evidence indicate that the high prevalence of the 30delG mutation arises from a mutation hot spot rather than from a founder effect. Genetic counseling for prelingual deafness has been so far considerably impaired by the difficulty in distinguishing genetic and non genetic deafness in families presenting with a single deaf child. Based on the results presented here, the development of a simple molecular test could be designed which should be of considerable help.   相似文献   
70.
Missense mutations in the beta-amyloid precursor protein gene (APP) co- segregate with a small subset of autosomal dominant familial Alzheimer's disease (FAD) cases wherein deposition of the 39-43 amino acid beta-amyloid (A beta) peptide and neurodegeneration are principal neuropathological hallmarks. To accurately examine the effect of missense mutations on APP metabolism and A beta production in vivo, we have introduced yeast artificial chromosomes (YACs) containing the entire approximately 400 kbp human APP gene encoding APP harboring either the asparagine for lysine and leucine for methionine FAD substitution at codons 670 and 671 (APP(K670N/M671L)), the isoleucine for valine FAD substitution at codon 717 (APP(V7171)) or a combination of both substitutions into transgenic mice. We demonstrate that, relative to YAC transgenic mice expressing wild-type APP, high levels of A beta peptides are detected in the brains of YAC transgenic mice expressing human APP(K670N/M671L) that is associated with a concomitant diminution in the levels of apha-secretase-generated soluble APP derivatives. Moreover, the levels of longer A beta peptides (species terminating at amino acids 42/43) are elevated in YAC transgenic mice expressing human APP(V7171). These mice should prove valuable for detailed analysis of the in vivo effects of the APP FAD mutations in a variety of tissues and throughout aging and for testing therapeutic agents that specifically alter APP metabolism and A beta production.   相似文献   
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