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71.
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   
72.
Protein phosphatase 2A (PP2A) is a multimeric enzyme, containing a catalytic subunit complexed with two regulatory subunits. The catalytic subunit PP2A C is encoded by two distinct and unlinked genes, termed Cα and Cβ. The specific function of these two catalytic subunits is unknown. To address the possible redundancy between PP2A and related phosphatases as well as between Cα and Cβ, the Cα subunit gene was deleted by homologous recombination. Homozygous null mutant mice are embryonically lethal, demonstrating that the Cα subunit gene is an essential gene. As PP2A exerts a range of cellular functions including cell cycle regulation and cell fate determination, we were surprised to find that these embryos develop normally until postimplantation, around embryonic day 5.5/6.0. While no Cα protein is expressed, we find comparable expression levels of PP2A C at a time when the embryo is degenerating. Despite a 97% amino acid identity, Cβ cannot completely compensate for the absence of Cα. Degenerated embryos can be recovered even at embryonic day 13.5, indicating that although embryonic tissue is still capable of proliferating, normal differentiation is significantly impaired. While the primary germ layers ectoderm and endoderm are formed, mesoderm is not formed in degenerating embryos.  相似文献   
73.
Ho  CP; Kim  RW; Schaffler  MB; Sartoris  DJ 《Radiology》1990,176(1):171-173
Dual-energy radiographic absorptiometry (DRA) was used to measure the bone mineral content and area density of lumbar vertebrae (L2-L3) in 11 cadavers. These data were subsequently compared with measured ash content and density. Excellent correlation was obtained between bone mineral content measured with DRA and ash weight (r = .963, P less than .0001). The accuracy error in determining mineral content in lumbar vertebrae with DRA was about 9%. In addition, strong correlation was observed between bone mineral density measured with DRA and ash density (r = .881, P less than .0001).  相似文献   
74.
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   
75.
76.
The serum noradrenaline (NA), homovanillic acid (HVA) and dopamine beta-hydroxylase (DBH) have been examined in neuroleptic-free and -treated patients, healthy first-degree relatives of the patients and normal subjects. Analysis of variance (ANOVA) revealed significant differences in the concentrations of serum NA(F = 2.91, p < 0.05) and HVA (F = 3.58, p < 0.05), and in the activity of serum DBH (F = 2.77, p < 0.05) among the four groups. The serum NA was significantly higher in neuroleptic-free patients (475 +/- 220 pg/ml, n = 18), than in healthy first-degree relatives (343 +/- 189 pg/ml, n = 37, p < 0.05) or in normal subjects (354 +/- 111 pg/ml, n = 17, p < 0.05), and it also was significantly higher in neuroleptic-treated patients (442 +/- 223 pg/ml, n = 58) than in healthy first-degree relatives (p < 0.05) or in normal subjects (p < 0.05). There was a trend towards high serum HVA in neuroleptic-free patients (11.3 +/- 6.3 ng/ml, n = 17) compared with the other three groups. The serum DBH activity was high in neuroleptic-free patients (31.2 +/- 15.6 nmol/min/ml, n = 17), and significantly in comparison with those treated with neuroleptic drugs (21.6 +/- 10.9 nmol/min/ml, n = 56, p < 0.05). There was a significant negative correlation between HVA concentration and DBH activity in the serum from neuroleptic-free patients (r = -0.64, n = 16, p < 0.01), and there appeared to be three subgroups with alterations of serum DBH activity and HVA concentration.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
77.
Rabbit antisera and mouse monoclonal antibodies have been prepared to bovine DARPP-32 (dopamine- and adenosine 3':5'-monophosphate-regulated phosphoprotein, Mr = 32,000), and used to study its regional, tissue, and phylogenetic distributions. The antibodies, none of which distinguished between dephospho-DARPP-32 and phospho-DARPP-32, were characterized and used to develop a sensitive and specific radioimmunoassay for DARPP-32. The radioimmunoassay, in conjunction with immunolabeling of SDS/PAGE transfers and immunoprecipitation of phosphorylated tissue extracts, was used to measure immunoreactive DARPP-32 in microdissected regions of rat CNS, in peripheral nervous and non-nervous tissues, and in CNS tissue from various animal species. The distribution of DARPP-32 was generally consistent with the interpretation that it is localized primarily to dopaminoceptive cells that possess dopamine-sensitive adenylate cyclase (D-1 dopamine receptors coupled to adenylate cyclase). Within the rat CNS, DARPP-32 was most highly concentrated in the basal ganglia. DARPP-32 was present in neostriatum from all six mammalian species tested (mouse, rat, guinea pig, rabbit, cow, and rhesus monkey) at concentrations of from 96 to 144 pmol/mg total protein, which constituted from 0.22 to 0.32% of the total protein. DARPP-32 was also identified at low levels in several peripheral tissues, including choroid plexus, parathyroid cells, adrenal chromaffin cells, posterior pituitary gland, pineal gland, and superior cervical sympathetic ganglion. A phylogenetic survey was carried out of proteins immunologically related to DARPP-32 in nervous tissue from nonmammalian species. DARPP-32-like proteins were identified in dopaminoceptive brain regions from representative members of the amniote vertebrate classes (birds and reptiles), while none was identified in dopaminoceptive brain regions from representative members of the anamniote vertebrate classes (bony fishes and amphibians) or in nervous tissue from representative members of several invertebrate classes.  相似文献   
78.
We investigate whether symptoms of pressure, tightness, and/or pain in the chest, neck, and/or throat after administration of the 5HT1B/1D agonist avitriptan were associated with objective impairment of the myocardial function on 12-lead electrocardiogram (ECG), continuous ECG (Holter) monitoring, and echocardiography. Migraine sufferers who in two-thirds of alt attacks treated with sumatriptan had experienced chest/throat/neck symptoms were chosen for study. Baseline measures included vital signs, a 12-lead ECG and an echocardiogram. Patients ( n =51) who had no clinically significant abnormality at baseline received a high dose (150 mg) of avitriptan orally outside of a migraine attack. If pressure, tightness, and/or pain in the chest, neck, and/or throat occurred, an ECG was obtained, and a repeat echocardiogram was done while the symptoms were present in order to monitor for impairment of myocardial function. If symptoms of these types did not occur within 60 min after administration of the study drug, a second echocardiogram was obtained. Forty-five patients (88%) reported at least one adverse event and 23 (45%) experienced pressure, tightness, and/or pain in the chest, neck, and/or throat after administration of avitriptan. No clinically significant myocardial abnormalities were observed in any patient, even in those who had experienced the targeted symptoms. No other serious adverse event occurred. We concluded that the typical 5HT1B/1D agonist-induced chest/throat/neck symptoms are most unlikely to be of cardiovascular origin.  相似文献   
79.
A woman presenting with recurrent purpura fulminans was eventually found to have inflammatory bowel disease. We suggest the inflammatory state resulted in a deficiency of functional protein C.  相似文献   
80.

Background  

The use of spirometry for early detection of chronic obstructive pulmonary disease (COPD) is still an issue of debate, particularly because of a lack of convincing evidence that spirometry has an added positive effect on smoking cessation. We hypothesise that early detection of COPD and confrontation with spirometry for smoking cessation may be effective when applying an approach we have termed "confrontational counselling"; a patient-centred approach which involves specific communication skills and elements of cognitive therapy. An important aspect is to confront the smoker with his/her airflow limitation during the counselling sessions. The primary objective of this study is to test the efficacy of confrontational counselling in comparison to regular health education and promotion for smoking cessation delivered by specialized respiratory nurses in current smokers with previously undiagnosed mild to moderate airflow limitation.  相似文献   
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