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81.
Delay in hematologic recovery after bone marrow transplantation (BMT) can extend and amplify the risks of infection and hemorrhage, compromise patients' survival, and increase the duration and cost of hospitalization. Because current studies suggest that granulocyte- macrophage (GM) colony-stimulating factor (CSF) may potentiate the sensitivity of hematopoietic progenitor cells to G-CSF, we performed a prospective, randomized trial comparing GM-CSF (250 micrograms/m2/d x 14 days) versus sequential GM-CSF x 7 days followed by G-CSF (5 micrograms/kg/d x 7 days) as treatment for primary or secondary graft failure after BMT. Eligibility criteria included failure to achieve a white blood cell (WBC) count > or = 100/microL by day +21 or > or = 300/microL by day +28, no absolute neutrophil count (ANC) > or = 200/microL by day +28, or secondary sustained neutropenia after initial engraftment. Forty-seven patients were enrolled: 23 received GM-CSF (10 unrelated, 8 related allogeneic, and 5 autologous), and 24 received GM- CSF followed by G-CSF (12 unrelated, 7 related allogeneic, and 5 autologous). For patients receiving GM-CSF alone, neutrophil recovery (ANC > or = 500/microL) occurred between 2 and 61 days (median, 8 days) after therapy, while those receiving GM-CSF+G-CSF recovered at a similar rate of 1 to 36 days (median, 6 days; P = .39). Recovery to red blood cell (RBC) transfusion independence was slow, occurring 6 to 250 days (median, 35 days) after enrollment with no significant difference between the two treatment groups (GM-CSF: median, 30 days; GM-CSF+G- CSF; median, 42 days; P = .24). Similarly, platelet transfusion independence was delayed until 4 to 249 days (median, 32 days) after enrollment, with no difference between the two treatment groups (GM- CSF: median, 28 days; GM-CSF+G-CSF: median, 42 days; P = .38). Recovery times were not different between patients with unrelated donors and those with related donors or autologous transplant recipients. Survival at 100 days after enrollment was superior after treatment with GM-CSF alone. Only 1 of 23 patients treated with GM-CSF died versus 7 of 24 treated with GM-CSF+G-CSF who died 16 to 84 days (median, 38 days) after enrollment, yielding Kaplan-Meier 100-day survival estimates of 96% +/- 8% for GM-CSF versus 71% +/- 18% for GM-CSF+G-CSF (P = .026). These data suggest that sequential growth factor therapy with GM-CSF followed by G-CSF offers no advantage over GM-CSF alone in accelerating trilineage hematopoiesis or preventing lethal complications in patients with poor graft function after BMT.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
82.
Kuter  DJ; Rosenberg  RD 《Blood》1995,85(10):2720-2730
Thrombopoietin (c-Mpl ligand) has recently been purified and is considered to be the humoral regulator of platelet production. To see whether this molecule possessed the physiologic characteristics necessary to mediate the feed-back loop between blood platelets and the bone marrow megakaryocytes, we determined the relationship between blood levels of thrombopoietin and changes in the circulating platelet mass. We developed a model of nonimmune thrombocytopenia in rabbits by the subcutaneous administration of busulfan. Compared with pretreatment plasma, plasma taken from all thrombocytopenic rabbits at their platelet nadir contained increased amounts of thrombopoietin. All of this activity was neutralized by soluble c-Mpl receptor. We subsequently measured the level of thrombopoietin in the circulation over the entire time course after the administration of busulfan. As the platelet mass declined, levels of thrombopoietin increased inversely and proportionally and peaked during the platelet nadir. With return of the platelet mass toward normal, thrombopoietin levels decreased accordingly. When platelets were transfused into thrombocytopenic rabbits near the time of their platelet count nadir, the elevated levels of thrombopoietin decreased. In addition, platelets were observed to remove thrombopoietin from thrombocytopenic plasma in vitro. These results confirm that thrombopoietin is the humoral mediator of megakaryocytopoiesis and suggest that the platelet mass may directly play a role in regulating the circulating levels of this factor.  相似文献   
83.
The HTLV-I tax gene protein (Tax) is not packaged within the mature viral particle from which the proteins for the commercially available enzyme-linked immunosorbent assay (ELISA) are derived. Screening of 162 individuals within a cohort of white intravenous (IV) drug abusers, previously identified as having an increased incidence of HTLV-I infection, demonstrated that seven of them had antibodies to the HTLV-I Tax protein but tested negative in HTLV-I ELISAs and Western blots prepared from purified virion proteins. Three out of 35 individuals in other behaviorally defined high-risk groups also displayed this limited pattern of reactivity to HTLV-I proteins. The presence of the anti-HTLV- I p40/Tax antibodies was determined by radioimmunoprecipitation assay (RIPA), which also revealed low levels of anti-env reactivity. The specificity of the anti-p40 reactivity was confirmed on specific Tax ELISAs and Western blots prepared from recombinantly produced Tax. In vitro gene amplification by the polymerase chain reaction (PCR) was used to establish the presence of sequences homologous to HTLV-I proviral DNA in four/four of these HTLV-I ELISA negative, Tax ELISA/Tax western blot/RIPA positive individuals. These data suggest that the true incidence of HTLV-I infection within high-risk cohorts is greater than previously reported.  相似文献   
84.
A phase I clinical trial was initiated to treat patients with stage IV B-derived chronic lymphocytic leukemia (CLL) with the IgG2a murine monoclonal antibody T101. This antibody binds to a 65,000-mol wt (T65) antigen found on normal T lymphocytes, malignant T lymphocytes, and B- derived CLL cells. All of the patients had a histologically confirmed diagnosis of advanced B-derived CLL and were refractory to standard therapy, and more than 50% of their leukemia cells reacted with the T101 antibody in vitro. The patients received T101 antibody two times per week, over two to 50 hours by intravenous administration in 100 mL of normal saline containing 5% human albumin. Twelve patients were treated with a fixed dosage of 1, 10, 50, or 100 mg, and one patient was treated with 140 mg of antibody. It was demonstrated that patients given two-hour infusions of 50 mg developed pulmonary toxicity, with shortness of breath and chest tightness. This toxicity was eliminated when infusions of 50 or 100 mg of T101 were prolonged to 50 hours. All dose levels caused a rapid but transient decrease in circulating leukemia cell counts. In vivo binding to circulating and bone marrow leukemia cells was demonstrated at all dose levels with increased binding at higher dosages. Antimurine antibody responses were not demonstrated in any patients at any time during treatment. Circulating free murine antibody was demonstrated in the serum of only the two patients treated with 100 mg of antibody as a 50-hour infusion and the patient treated with 140 mg of antibody over 30 hours. Antigenic modulation was demonstrated in patients treated at all dose levels but was particularly apparent in patients treated with prolonged infusions of 50 and 100 mg of antibody. We were also able to demonstrate antigenic modulation in lymph node cells, which strongly suggests in vivo labeling of these cells. Overall, T101 antibody alone appears to have a very limited therapeutic value for patients with CLL. The observations of in vivo labeling of tumor cells, antigenic modulation, antibody pharmacokinetics, toxicity, and antimurine antibody formation may be used in the future for more effective therapy when drugs or toxins are conjugated to the antibody.  相似文献   
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Previous theories and research have suggested there are two distinct types of male-to-female (MF) transsexuals and these types can be distinguished by their sexuality. Using the scales Attraction to Femininity in Males, Core Autogynephilia, Autogynephilic Interpersonal Fanasy, and Attraction to Transgender Fiction as indicator variables, taxometric analysis was applied to an online-recruited sample of 308 MF transsexuals to investigate whether such a distinction is justified. In accordance with previous research findings, MF transsexuals categorized as “nonandrophilic” scored significantly higher on Core Autogynephilia than did those categorized as “androphilic”; they also scored significantly higher on Attraction to Femininity in Males and Attraction to Transgender Fiction. Results of one of the taxometric procedures, L-Mode, gave slightly more support for a dimensional, rather than taxonic (two-type), latent structure. Results of the two other taxometric procedures, MAMBAC and MAXCOV, showed greater support for a dimensional latent structure. Although these results require replication with a more representative sample, they show little support for a taxonomy, which contradicts previous theory that has suggested MF transsexuals’ sexuality is typological.  相似文献   
88.

Introduction and hypothesis

Our goal was to determine psychosexual outcome after labiaplasty in the long-term with specific measures of genital body image and sexual dysfunction.

Method

We conducted a prospective study with a matched-comparison group of women not wanting labiaplasty. Forty-nine women were compared against a group of 39 women matched for age, sexual orientation, ethnicity, and marital status. The labiaplasty group was assessed before, 3 months after and between 11 and 42 months after surgery. The comparison group was assessed at two time points 3 months apart to control for the passage of time. The primary outcome measure was the Genital Appearance Satisfaction (GAS) scale.

Results

Of the 49 women receiving labiaplasty, 19 (38.8 %) were lost to follow-up but were reassessed clinically. Twenty-four of 25 (96 %) women in the labiaplasty group showed a reliable and clinically significant improvement on the GAS scale 3 months after the procedure; 21/23 (91.3 %) showed an improvement at the long-term follow-up. A large effect size was found for improvements on the GAS scale in the labiaplasty group. Small-effect sizes were found for improvements in sexual functioning. Nine women obtaining labiaplasty met diagnostic criteria for body dysmorphic disorder before the operation; eight lost that diagnosis at the 3-month follow-up; 26 % reported minor side effects.

Conclusions

Labiaplasty is effective in improving genital appearance and sexual satisfaction, but larger studies are required to determine the prevalence of potential side effects.  相似文献   
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