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排序方式: 共有417条查询结果,搜索用时 15 毫秒
81.
HPLC分离测定格列齐特片及其有关物质   总被引:6,自引:0,他引:6  
目的:建立新的HPLC法分离测定格列齐特征及其有关物质。方法:色谱条件为:Shim-Pack VP-ODS(5um,150mm*4.6mm i.d.)色谱柱;甲醇-0.02mol/L磷酸(用三乙胺调节PH至3.5),(70:30)为流动相;检测波长为229nm。结果:在50-300ug;/ml的浓度范围内线性关系良好。r=0.9999(n=6);平均回收率为100.5%,RSD为0.17%(n=6),重复进样RSD为0.12%(n=6),格列齐特及其有关物质得到基线分离。结论:本法简便,快速,准确,适用于格列齐特及其制剂的质量控制。  相似文献   
82.
The UTX gene escapes X inactivation in mice and humans   总被引:7,自引:3,他引:7  
We recently have identified a ubiquitously transcribed mouse Y chromosome gene, Uty , which encodes a tetratricopeptide repeat (TPR) protein. A peptide derived from the UTY protein confers H-Y antigenicity on male cells. Here we report the characterization of a widely transcribed X-linked homologue of Uty , called Utx , which maps to the proximal region of the mouse X chromosome and which detects a human X-linked homologue at Xp11.2. Given that Uty is ubiquitously transcribed, we assayed for Utx expression from the inactive X chromosome (Xi) in mice and found that Utx escapes X chromosome inactivation. Only Smcx and the pseudoautosomal Sts gene on the mouse X chromosome have been reported previously to escape inactivation. The human UTX gene was also found to be expressed from Xi. We discuss the significance of these data for our understanding of dosage compensation of X-Y homologous genes in humans and mice.   相似文献   
83.
In a human in-vitro fertilization (IVF) programme, the effect of co- culture of embryos with human fibroblasts was evaluated with respect to pregnancy rate and embryo development. Patients were included in the study after giving informed written consent. The IVF treatments were randomly assigned by stratification of both age (<36 versus > or =36 years) and previous IVF attempts (yes versus no). After fertilization was established, the zygotes were transferred to a 4-well dish with or without fibroblasts and cultured for 2 days. On the third day after ovum pick-up (OPU), cell number and quality [5 (good) to 1 (poor)] of the embryos were scored and a maximum of three embryos was transferred. Supernumerary embryos of good quality were cryopreserved. The design of this study was a group sequential trial with the objective of detecting differences between pregnancy rates following IVF with conventional incubation or incubation in co-culture with fibroblasts. This design included one evaluation at half-way data collection. In the study, 148 patients had an OPU, of whom 77 were allocated to the co-culture group. There was no statistically significant difference in pregnancy rate, cell number and embryo quality between the two groups. The ongoing pregnancy rate per embryo transfer was 27% in co-culture and 30% in the conventional culture group. The implantation rates per transferred embryo were 17 and 18% respectively. Using a multivariate logistic regression model for the probability of ongoing pregnancies, the odds ratio of co-culture, adjusted for age and previous IVF attempts, was not statistically significant. In conclusion, co-culture with human fibroblasts does not contribute to an improvement of embryo quality nor to a higher pregnancy rate after IVF in an unselected group of patients.   相似文献   
84.
In-vitro maturation (IVM) of oocytes is a promising technique to reduce the costs and avert the side-effects of gonadotrophin stimulation for in-vitro fertilization (IVF). The pregnancy rates from oocytes matured in vitro are much lower than those of in-vivo stimulation cycles indicating that optimization of IVM remains a challenge. Therefore, we investigated the effect of supplementation of the medium with gonadotrophins, oestradiol and epidermal growth factor (EGF) and the effect of retaining or removing the cumulus cells on nuclear and cytoplasmic maturation of immature oocytes. Human germinal vesicle (GV) oocytes obtained after gonadotrophin stimulation for intracytoplasmic sperm injection (ICSI) were cultured in a complex defined medium either supplemented with gonadotrophins, oestradiol and physiological concentrations of EGF (2 ng/ml) or gonadotrophins and oestradiol alone. The cumulus cells were either removed or kept intact. In GV stage oocytes cultured without cumulus (group I) significantly more oocytes reached the metaphase II (MII) stage at 30 h in media supplemented with EGF (64.3 versus 33.9%, P < 0.003). For oocytes cultured with intact cumulus (group II), more oocytes reached MII at 30 h than in group I, but there was no difference in medium with or without EGF supplementation (81.8 and 79.8% respectively). Cytoplasmic maturation of MII oocytes was judged from their capability to activate and fertilize after ICSI. In group I, the rates of activation and normal fertilization were similar. However, in group II, significantly more oocytes underwent normal fertilization in the EGF-supplemented than the unsupplemented group (71.7 versus 45.6%, P < 0.05). The cleavage rates of the fertilized oocytes were similar in the sibling oocyte subgroups cultured with or without EGF supplementation, but the overall cleavage rates were higher in cumulus-intact compared to cumulus-denuded oocytes (88.9 versus 47.8%, P < 0.001). Thus, supplementation of the maturation medium with EGF and maintenance of the cumulus during culture improve the nuclear and cytoplasmic maturation of human oocytes in vitro.   相似文献   
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86.
Context  Depression is a common condition associated with significant morbidity in adolescents. Few depressed adolescents receive effective treatment for depression in primary care settings. Objective  To evaluate the effectiveness of a quality improvement intervention aimed at increasing access to evidence-based treatments for depression (particularly cognitive-behavior therapy and antidepressant medication), relative to usual care, among adolescents in primary care practices. Design, Setting, and Participants  Randomized controlled trial conducted between 1999 and 2003 enrolling 418 primary care patients with current depressive symptoms, aged 13 through 21 years, from 5 health care organizations purposively selected to include managed care, public sector, and academic medical center clinics in the United States. Intervention  Usual care (n = 207) or 6-month quality improvement intervention (n = 211) including expert leader teams at each site, care managers who supported primary care clinicians in evaluating and managing patients’ depression, training for care managers in manualized cognitive-behavior therapy for depression, and patient and clinician choice regarding treatment modality. Participating clinicians also received education regarding depression evaluation, management, and pharmacological and psychosocial treatment. Main Outcome Measures  Depressive symptoms assessed by Center for Epidemiological Studies-Depression Scale (CES-D) score. Secondary outcomes were mental health–related quality of life assessed by Mental Health Summary Score (MCS-12) and satisfaction with mental health care assessed using a 5-point scale. Results  Six months after baseline assessments, intervention patients, compared with usual care patients, reported significantly fewer depressive symptoms (mean [SD] CES-D scores, 19.0 [11.9] vs 21.4 [13.1]; P = .02), higher mental health–related quality of life (mean [SD] MCS-12 scores, 44.6 [11.3] vs 42.8 [12.9]; P = .03), and greater satisfaction with mental health care (mean [SD] scores, 3.8 [0.9] vs 3.5 [1.0]; P = .004). Intervention patients also reported significantly higher rates of mental health care (32.1% vs 17.2%, P<.001) and psychotherapy or counseling (32.0% vs 21.2%, P = .007). Conclusions  A 6-month quality improvement intervention aimed at improving access to evidence-based depression treatments through primary care was significantly more effective than usual care for depressed adolescents from diverse primary care practices. The greater uptake of counseling vs medication under the intervention reinforces the importance of practice interventions that include resources to enable evidence-based psychotherapy for depressed adolescents.   相似文献   
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89.
OBJECTIVE: To compare the incidence, symptomatology and course of mastocytosis with onset in childhood and in adults. DESIGN: Retrospective study of 101 patients with mastocytosis who were referred from 1980 to 1998. PATIENTS: Medical records of 65 cases of mastocytosis with onset in childhood and 36 in adulthood were analysed. The clinical course was assessed in a subgroup consisting of 33 subjects with childhood onset who were followed up until at least adolescence and 12 subjects with adult onset who were followed up for at least 10 years. RESULTS: The onset of the disease occurred before the age of 2 years in 50% and between the ages of 2 and 15 years in 14% of cases (childhood onset). In 36% of patients onset occurred at the age of 16 years and older (adult onset). An incidence peak of 60% was noted in the first year of life. Mast cell-mediated symptoms were not experienced by 21 of 36 adult onset mastocytosis patients nor by 27 of 65 childhood onset mastocytosis patients. Complete resolution was observed in five of 33 children. The majority of childhood onset cases (21 of 33) showed some improvement. Complete resolution was achieved in three of 12 adults. The majority of the remaining adults (eight of 12) showed no improvement. CONCLUSIONS: We confirm the incidence of onset of mastocytosis previously reported in the literature. We conclude that childhood onset mastocytosis is much less transitory than generally is assumed, although improvement occurs in the majority of cases. Symptomatology and clinical course of adult onset mastocytosis is less severe than suggested in the literature.  相似文献   
90.
Pruritus in hepatic cholestasis has been suggested to be secondary to a high concentration of serum bile acids. Rifampicin, which inhibits the uptake of bile acids by hepatocytes, has been used to treat pruritus. To determine the efficacy of rifampicin as a treatment for refractory pruritus, the medical records of 33 children (median age 25 months, range 4-135; 19 boys) with chronic cholestasis liver disease (21 with Alagille's syndrome, eight with progressive intrahepatic cholestasis, one with extrahepatic biliary atresia, one with an inborn error of bile acid metabolism, and one with cryptogenic cirrhosis) were reviewed retrospectively. The median dose of rifampicin was 5(4-10) mg/kg/day. The median duration of intake was 36(4-120) weeks. Complete relief of pruritus was noted in five (15%) patients and a partial response in 12 (36%). Overall, no significant difference was noted in the laboratory parameters before and after treatment with rifampicin. In the 21 patients with Alagille's syndrome, however, a significant decrease in alkaline phosphatase was seen before and after one and six months of starting treatment. No adverse side effects were seen. Rifampicin appears to be effective in the treatment of refractory pruritus. A prospective study is warranted to assess further the effect of rifampicin treatment in children with hepatic cholestasis.  相似文献   
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