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51.
The goal of this phase II multicenter clinical trial was to evaluate a new intensive chemotherapy program for adults with untreated acute lymphoblastic leukemia (ALL) and to examine prospectively the impact of clinical and biologic characteristics on the outcome. One hundred ninety-seven eligible and evaluable patients (16 to 80 years of age; median, 32 years of age) received cyclophosphamide, daunorubicin, vincristine, prednisone, and L-asparaginase; 167 patients (85%) achieved a complete remission (CR), 13 (7%) had refractory disease, and 17 (9%) died during induction. A higher CR rate was observed in younger patients (94% for those < 30 years old, 85% for those 30 to 59 years old, and 39% for those > or = 60 years old, P < .001) and in those who had a mediastinal mass (100%) or blasts with a T-cell immunophenotype. Eighty percent of B-lineage and 97% of T-cell ALL patients achieved a CR (P = .01). The coexpression of myeloid antigens did not affect the response rate or duration. Seventy percent of those with cytogenetic or molecular evidence of the Philadelphia (Ph) chromosome and 84% of those without such evidence achieved a CR (P = .11). Patients in remission received multiagent consolidation treatment, central nervous system prophylaxis, late intensification, and maintenance chemotherapy for a total of 24 months. After a median follow-up time of 43 months, the median survival for all 197 patients is 36 months; the median remission duration for the 167 CR patients is 29 months. Favorable pretreatment characteristics relative to remission duration or survival are younger age, the presence of a mediastinal mass or lymphadenopathy, a white blood cell count (WBC) less than 30,000/microL, L1 morphology, T or TMy immunophenotype, and the absence of the Ph chromosome. The estimates of the proportion surviving at 3 years are 69% for patients less than 30 years old, 39% for those 30 to 59 years old, 89% for those who had a mediastinal mass, 59% with WBC less than 30,000/microL, 63% with L1 morphology, 69% for T or TMy antigen expression, and 62% for those who lack the Ph chromosome. Fifteen patients (8%) had no unfavorable prognostic factors and have an estimated probability of survival at 5 years of 100% (95% confidence interval, 77% to 100%). This intensive chemotherapy regimen produces a high remission rate and a high proportion of durable remissions in adults with ALL.  相似文献   
52.
报道4个N-(1-[1-乙氧羰基-3-(对甲)苯氨甲酰基]丙基甘氨酰}-N-取代甘氨酸(XI1~4)和5个1-[1-乙(或甲)氧羰基-3-(对甲)苯氨甲酰基]丙基-4-取代-1,4-哌嗪-2,5-二酮(XII1~5)共9个估计有血管紧张素转化酶抑制活性化合物的合成和鉴定。所有这些化合物及9个相应的酯(X1~9)均未见文献报道。药理初试结果,化合物XII2,XII5,XI4和XII1均有较强降压活性。  相似文献   
53.
54.
Breath-hold, contrast-enhanced, three-dimensional MR angiography   总被引:22,自引:0,他引:22  
  相似文献   
55.

Background  

A strong increase in smoking is noted especially among adolescents. In the Netherlands, about 5% of all 10-year olds, 25% of all 13-year olds and 62% of all 17-year olds report ever smoking. In the U.S., an intervention program called 'Smoke-free Kids' was developed to prevent children from smoking. The present study aims to assess the effects of this home-based smoking prevention program in the Netherlands.  相似文献   
56.
57.
Summary A metabolic study showed that hypophysectomy does not induce steatorrhea in rats on diets containing 6% and 30% fat, respectively. The data suggest that hypophysectomized animals absorb fat at least as efficiently as normal rats.Supported by Grants TI-AM-5424 and AM-09332 from the National Institute of Arthritis and Metabolic Diseases, U. S. Public Health Service.Work done during a summer fellowship program as third-year Medical Student, Tufts University Medical School.  相似文献   
58.
Burns  CP 《Blood》1975,45(5):643-651
The metabolism of an essential amino acid, isoleucine, by human leukemic and gradient-separated normal human leukocytes of various types and maturity was studied. Blood leukocytes were isolated and incubated with (U-14C) isoleucine. Separation of metabolic intermediates was accomplished by sequential extraction. The rate of isoleucine incorporation into protein by immature cells from untreated patients with acute leukemia (15.9 plus or minus 2.4 nmoles/hr per 10-8 leukocytes) was considerably higher than the rates of incorporation by mature neutrophils (3.2 plus or minus 0.5 nmoles/hr per 10-8 leukocytes), lymphocytes (7.7 plus or minus 1.2 nmoles/hr per 10-8 leukocytes), and eosinophils (6.2 plus or minus 1.3 nmoles/hr per 10-8 leukocytes). Those cell preparations with more blast cells had higher rates of protein synthesis. In addition, those cells with greater thymidine incorporation had higher rates of protein synthesis. The leukocytes both oxidized isoleucine and incorporated it into cell isoleucine and incorporated it into cell lipid. The rates of these metabolic processes were characteristic for various types and maturity of leukocytes. This study demonstrates a relationship of rate of protein synthesis to leukocyte immaturity. This relationship is maintained in neoplastic leukocytes. It suggests that the requirement of the mitotic process for newly synthesized protein is greater than that for the elaboration of the protein products of the mature leukocyte.  相似文献   
59.
Three cases of multiple sclerosis, all confirmed pathologically, are described in whom both the unusual clinical features and the CT scan appearances suggested cerebral tumours. The failure of mass effect reliably to differentiate plaques and tumours on a CT scan is stressed and the literature relating to CT scanning in multiple sclerosis is reviewed.  相似文献   
60.
One hundred forty-eight patients with gastrointestinal disease, 50 patients with the irritable bowel syndrome (IBS) and 49 each with peptic ulcer and inflammatory bowel disease, were interviewed to determine if they had proctalgia fugax (PF) and if the symptom was associated with the IBS. One-third of the patients had PF. It occurred in 51% of females and 12% of males (p less than 0.001). When corrected for sex, PF was no more prevalent in IBS than in peptic ulcer or inflammatory bowel disease. Only two of six previously described IBS symptoms were more prevalent in the PF patients. Attacks occurred in the day in 94%, and one-third of sufferers related them to defecation. The pain was localized in the anus in 90%, occurred less than five times a year in 51%, and lasted less than 1 min in 57%. In most, activity was not interrupted by this pain and only 20% had ever reported it to a physician. PF is very common among patients with abdominal symptoms, but is not related to the IBS. Since it is infrequent, benign, and transient, PF is usually not mentioned to the physician.  相似文献   
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