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971.
JK McLaughlin O Nyrén WJ Blot L Yin S Josefsson JF Fraumeni HO Adami 《Canadian Metallurgical Quarterly》1998,90(2):156-158
Complementary DNAs encoding the heavy and light chains of the Fab fragment of mouse agglutinating monoclonal antibody against human red blood cells were cloned by polymerase chain reaction and their nucleotide sequences were determined. The sequence analysis showed that the variable regions of the heavy and light chains were the members of mouse heavy-chain subgroup IIa and kappa light-chain subgroup I, respectively. A few unusual amino acids in the constant regions of the heavy chain were also recognized. 相似文献
972.
In three women aged 51, 37 and 58 years, with a palpable tumour in the breast, excision and pathological examination led to the diagnosis of 'phyllodes tumour'. During 3-5 years after radical excision, in one patient followed by radiotherapy, no recurrences were seen. This rare breast tumour with a variable clinical course usually affects women between the ages of 30 and 50. There is often a large tumour and (or) rapid growth. Mammography and ultrasound are unhelpful diagnostically. Cytology is unreliable as the tumour is heterogeneous. Histologically the tumour can be benign, borderline malignant or malignant. Surgical excision with a margin of > or = 1 cm is the therapy of choice. The risk of recurrence after insufficient excision is considerable and histological deterioration can occur. Multiple samples, examination of resection margins and investigation into atypia, mitotic activity and stromal overgrowth are essential for making a prognosis and a treatment plan. In case of doubt regarding radicality, surgeon and pathologist should compare views; non-radicality necessitates re-excision. 相似文献
973.
AN Wymenga WT van der Graaf FL Spijkervet W Timens H Timmer-Bosscha WJ Sluiter EG de Vries NH Mulder 《Canadian Metallurgical Quarterly》1997,76(8):1062-1066
Patients receiving high-dose chemotherapy (HD-CT) are at risk of severe mucositis. Most prevention studies evaluate the degree of mucositis on clinical, and therefore subjective, measurements. The aim of this study was to develop an objective in vitro assay of chemotherapy-induced mucositis. Twelve patients with locally advanced breast carcinoma received HD-CT followed by peripheral stem cell reinfusion. Before and twice weekly after HD-CT, the mucosa was evaluated by an oral washing, a buccal smear and the World Health Organization (WHO) toxicity grading; furthermore, blood leucocyte levels were determined. For the oral washings, the percentage of viable epithelial cells was determined by trypan blue dye exclusion and leucocytes were counted by fluorescence microscopy after incubation with acridine orange. Maturity of buccal cells was assessed by staining buccal smears for morphology according to Papanicolaou (Whitacker D and Williams V, 1994). Eight healthy volunteers served as controls. The mean percentage (+/- s.e.m.) of viable oral epithelial cells was stable in controls (44 +/- 2%). In patients, they increased after HD-CT, which was significant after day 7 compared with pretreatment (P < or = 0.05). In addition, a shift from mature to immature epithelial cells in buccal smears was observed. Oral leucocyte levels were closely correlated with the blood leucocyte counts. The WHO score followed the results of these other evaluations with some delay. The viability of buccal cells obtained by oral washings increases after HD-CT. This is possibly because of desquamation of the upper oral mucosa layer, with a shift from mature to more immature cells. These data can be quantitated, and this assay may therefore be useful in studies aimed at prevention of mucositis. 相似文献
974.
975.
PW Hermans SK Saha WJ van Leeuwen HA Verbrugh A van Belkum WH Goessens 《Canadian Metallurgical Quarterly》1996,34(6):1373-1379
Seventy-eight Salmonella typhi strains isolated in 1994 and 1995 from patients living in Dhaka, Bangladesh, were subjected to phage typing, ribotyping, IS200 fingerprinting, and PCR fingerprinting. The collection displayed a high degree of genetic homogeneity, because restricted numbers of phage types and DNA fingerprints were observed. A significant number of the S. typhi strains (67%) were demonstrated to be multiple drug resistant (MDR). The vast majority of the MDR strains were resistant to chloramphenicol, ampicillin, trimethoprim, streptomycin, sulfamethoxazole, and tetracycline (R type CATmSSuT), a resistance phenotype that has also frequently been observed in India. Only two strains displayed a distinct MDR phenotype, R type AT-mSSuT. Pulsed-field gel electrophoresis demonstrated the presence of large plasmids exclusively in the MDR strains of both R types. The plasmids present in the S. typhi strains of R type CATmSSuT could be conjugated to Escherichia coli and resulted in the complete transfer of the MDR phenotype. PCR fingerprinting allowed discrimination of MDR and susceptible strains. The DNA fragments enabling discrimination of MDR and susceptible S. typhi strains by PCR were useful genetic markers for identifying MDR encoded by large plasmids of the H1 incompatibility group. 相似文献
976.
977.
JW Barnard AF Seibert VR Prasad DA Smart SJ Strada AE Taylor WJ Thompson 《Canadian Metallurgical Quarterly》1994,77(2):774-781
Isoproterenol (ISO) and forskolin, agents that increase adenosine 3',5'-cyclic monophosphate (cAMP) via adenylyl cyclase activation, reverse lung injury associated with increased microvascular permeability. We studied the role of rolipram, a relatively isozyme-selective cAMP phosphodiesterase (PDE) inhibitor, in reversing increased capillary permeability due to ischemia-reperfusion (I/R), a form of oxidant injury in the lung, by using the isolated perfused rat lung model. Rolipram (2 microM) administered after 45 min of ischemia and 45 min of reperfusion reduced I/R-increased permeability as measured by the capillary filtration coefficient to control lung values. Computer image analysis of air space edema and perivascular cuffing, as well as wet-to-dry weight ratios, confirms the permeability reversal by rolipram administration. Rolipram inhibition of cAMP PDE in the lung was assessed by using [3H]adenine prelabeling adapted for the whole lung and perfusate [3H]cAMP accumulation. Rolipram failed to increase perfusate cAMP alone but dramatically increased perfusate cAMP above ISO alone. Dose-response relationships of ISO or rolipram show a close correlation of the half-maximal effective dose (ED50) for injury reversal and perfusate cAMP production. The combination of rolipram and ISO produced synergistic reversal of I/R injury. We conclude that reversal of I/R-induced increased microvascular permeability can be achieved with rolipram and that the mechanism of action of rolipram is probably through PDE isozyme-selective inhibition. The similarity of the ED50 values for cAMP efflux and reversal of permeability increases also supports a close coupling between cAMP accumulation and endothelial cell permeability. 相似文献
978.
In the Diego blood group, the frequency of the Di(a + b +) or Di(a + b -) phenotype among Chinese in Taiwan is estimated to be 3.2%. Here we report a case of severe hemolytic disease caused by anti-Di(a). The baby's total bilirubin elevated to 23 mg/dl at the age of 72 hours. A blood exchange transfusion and phototherapy were performed. We suggest to include Diego positive cell panels in testing antibody specificities that are likely to be encountered in this population. 相似文献
979.
980.
Experiments examined how learning processes modulate tolerance to discriminative stimulus effects of morphine. Rats were trained to discriminate saline and 3.2 mg/kg morphine, and the doses of morphine required to mimic the training dose were determined before, during and after repeated treatment with saline or high doses of morphine (10 mg/kg, b.i.d.). In one set of experiments, training was either suspended or continued with saline and the original training dose during a 2-week treatment regimen. When training was suspended, high-dose morphine treatment increased the dose of morphine required for stimulus effects approximately 3-fold. Tolerance persisted 2 days after treatment ended, but disappeared within 7 days. In contrast, continued training with saline and 3.2 mg/kg morphine during high-dose treatment both attenuated development of tolerance and transferred control to lower doses. Transfer of control to lower doses appeared conditional upon recent termination of high-dose treatment, as it disappeared within 7 days. Treatment with saline did not change the doses of morphine required for stimulus effects under either training condition. A final experiment examined whether high-dose treatment could transfer control to higher doses of morphine. The treatment dose of 10 mg/kg morphine itself was used as the training dose during a 2-week treatment regimen. The dose of morphine required for stimulus effects increased 2- to 4-fold during treatment, but quickly returned to control values when treatment ended. These results extend previous findings that conditioning and pharmacodynamic processes jointly regulate development of tolerance to discriminative effects of morphine. 相似文献