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81.
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   
82.
Cai  SP; Chang  CA; Zhang  JZ; Saiki  RK; Erlich  HA; Kan  YW 《Blood》1989,73(2):372-374
We used in vitro DNA amplification by the polymerase chain reaction and nonradioactive probes for prenatal diagnosis of beta thalassemia in Chinese from the Guangdong province. Exact molecular diagnoses were made in all 20 fetuses studied over a 6-month period. We conclude that this method of prenatal diagnosis for beta thalassemia is a viable approach in many parts of the world where this disease is common.  相似文献   
83.
84.
Intestinal transplant is a therapeutic challenge not just surgically but also logistically because of the multidisciplinary expertise and resources required. A large proportion of patients who undergo massive bowel resection and develop intestinal failure have poor outcome, because of inability to sustain long-term parenteral nutrition and limited availability of intestinal and multi-visceral transplantation facilities. We report the first successful isolated intestinal transplant from India.  相似文献   
85.
ABO incompatibility is the commonest reason for rejection of donors in living donor liver transplantation (LDLT). The donor pool could be expanded by 25 % to 35 % if the ABO barrier is overcome. In the absence of pre-conditioning, transplantation across the blood groups is fraught with the almost universal risk of antibody-mediated rejection (AMR) that rapidly leads to graft loss. However, AMR can be prevented by removal of preformed antibodies and reducing their production by B cells. We describe our initial experience of three cases of ABO-incompatible (ABO-i) LDLT: a 42-year-old male, an 8-month-old male and a 28-month-old female, all of blood group O+ who received blood group B + right lobe, B + left lateral segment, and A + left lateral segment liver grafts, respectively. Pre-LDLT conditioning included administration of anti-CD20 antibody (Rituximab®) to the adult 4 weeks prior, and four to seven sessions of double-filtration plasmapheresis to all, to remove preformed antibodies and achieve anti-donor blood group antibody (ADA) titers of ≤1:16 IgG and ≤1:8 IgM, respectively. In addition, cases 1 and 3 received mycophenolate mofetil for 7 days prior to LDLT. After LDLT, all three patients achieved normal graft function over 8–17 days with no evidence of AMR and without the need for further plasmapheresis. Postoperative complications included portal vein thrombosis (one successfully re-explored), CMV (one), Pseudomonas and Klebsiella sepsis (one each), and abdominal collection (one treated with percutaneous drainage). All are currently well with normal graft function and low ADA titers at 8, 16, and 19 months after ABO-i LDLT.  相似文献   
86.
Transcatheter aortic valve implantation (TAVI) is maturing strongly as an alternative to surgical aortic valve replacement (SAVR) in patients who are inoperable/high risk for open heart surgery. General anesthesia (GA) is the usual mode of anesthesia in these patients, but local anesthesia with conscious sedation (LACS) has recently been described as a safe alternative with some added advantages. We report 2 cases who were unfit for GA and were done successfully under LACS.  相似文献   
87.
Abstract

Objective:

Protein kinase B (PKB/Akt), which is phosphorylated and activated by upstream activators, exerts critical neuroprotective effects by phosphorylating downstream targets after traumatic brain injury (TBI). Studies on the regulation of Akt will be crucial for our understanding of neuronal survival. The goal of this study is to investigate the effects of carboxyl-terminal modulator protein (CTMP) on phosphorylation of Akt and neurological function in a mouse model of TBI.

Methods:

Traumatic brain injury in mice was performed by a controlled cortical impact device. The expression of Akt, phospho-Akt, and CTMP was examined in the injured cortices by immunohistochemistry and Western blot analysis. To determine the effects of CTMP, small interfering RNAs (siRNAs) directed against CTMP were injected in mice with TBI, and the expression of phosphorylated Akt and neurological function were evaluated.

Results:

Phospho-Akt significantly increased at 4 hours post-TBI in the nucleus (P < 0·01) and remained at high levels until 72 hours after TBI, as shown by Western blot analysis. In the cytosol, the expression of phospho-Akt reached its peak at 4 hours post-TBI, but decreased markedly at 24 hours and maintained below pre-TBI levels until 72 hours post-TBI. Interestingly, the expression of CTMP significantly increased 4 hours after TBI (P < 0·01) and sustained those levels until 72 hours without dramatic changes. Treatment with CTMP siRNA effectively augmented the phosphorylation of Akt and significantly improved the neurological functional recovery up to 28 days post-TBI.

Conclusion:

We conclude that Akt is phosphorylated and translocated to nucleus after TBI to exert neuroprotective effects. However, CTMP is simultaneously triggered to inhibit the phosphorylation of Akt. Inhibition of CTMP by siRNA improves the recovery of neurological functions after TBI.  相似文献   
88.
Background This human cadaveric study introduces a laboratory model to establish and compare the fixation stability of the distal femoral locking plate (DFLP) and dynamic condylar screw (DCS) in distal femoral fracture fixation.Materials and methods The study was conducted on 16 fresh cadaveric femoral specimens, 8 implanted with the DCS and the other 8 with the DFLP. The construct was made unstable by removing a standard-sized medial wedge with a 1-cm base (gap osteotomy) beginning 6 cm proximal to the lateral joint line in the distal metaphyseal region with loss of the medial buttress. Each specimen underwent axial and torsional stiffness testing along with cyclic axial loading to failure. The mean DEXA value for the DFLP group was 0.82 g/cm2 and in the DCS group was 0.79 g/cm2.Results Axial stiffness in the DFLP group was significantly higher than in the DCS group, but no significant difference was found in torsional stiffness between the groups. A significant difference was found in the load-to-failure results between the groups. Plastic and total deformation was significantly higher in constructs in the DCS group than in those in the DFLP group. Total energy absorbed before construct failure was also significantly higher in the DFLP group than in the DCS group.Conclusions The DFLP construct proved stronger than the DCS in both axial stiffness and cyclic loading, but similar in torsional stiffness in biomechanical testing in a simulated A3 distal femoral fracture.  相似文献   
89.
90.
Mycobacterium tuberculosis Beijing genotype strains are rapidly disseminating, frequently hypervirulent, and multidrug resistant. Here, we describe a method for their rapid detection by real-time PCR that targets the specific IS6110 insertion in the dnaA-dnaN genome region. The method was evaluated with a geographically and genetically diverse collection representing areas in East Asia and the former Soviet Union in which the Beijing genotype is endemic and epidemic (i.e., major foci of its global propagation) and with clinical specimens.  相似文献   
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