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新生儿远程医疗   总被引:1,自引:1,他引:0  
正医生短缺是一个世界性的问题。最近,世界卫生组织(WHO)报告全球短缺430万名医生、护士和其他卫生保健专业人员。在发展中国家,由于医学院的数量和能力有限,这种短缺更加严重。包括美国、加拿大、新西兰、英国、澳大利亚和德国在内的许多发达国家都报告了类似的问题~([1])。美国医学院协会估计,到2032年,美国医生缺口将达到46 900~121 900人~([2])。医生短缺将导致城市和农村地区都得不到足够的医疗。目前,城市地区每万名居民医生的数量是农村地区的两倍。在亚专科医  相似文献   
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Objective: This study aims to evaluate the change in serum anti-Mullerian hormone (AMH) levels in patients with morbid obesity undergoing bariatric surgery for weight loss.

Material and methods: In this prospective observational study, 75 patients of reproductive age (20–35 years) undergoing bariatric surgery for morbid obesity were followed up after six months to determine the changes in weight, Body Mass Index (BMI), menstrual pattern and serum AMH. The results were further studied on basis of pre operative classification of patients in polycystic ovary syndrome (PCOS) and non-PCOS group.

Result: The serum AMH levels were statistically higher in patients of PCOS group pre operatively and at the end of six months in comparison to non-PCOS patients. The AMH values reduced post operatively in both groups significantly so much in the values though not significant statistically. Non-PCOS patients had lower AMH values pre operatively and showed a trend towards reducing ovarian reserve after six months. The overall change in AMH values in both groups was statistically significant as was the normalization of menstrual irregularity.

Conclusion: Morbidly obese patients with PCOS appear to benefit from bariatric surgery both in terms of regularization of menstrual function and normalization of serum AMH values.  相似文献   

25.
Leishmania donovani is an intracellular protozoan parasite that impairs the host macrophage immune response to render it suitable for its survival and establishment. L. donovani-induced immunosuppression and alteration of host cell signaling is mediated by ceramide, a pleiotropic second messenger playing an important role in regulation of several kinases, including mitogen-activated protein kinase and phosphatases. We observed that the endogenous ceramide generated during leishmanial infection led to the dephosphorylation of protein kinase B (PKB) (Akt) in infected cells. The study of ceramide-mediated Akt phosphorylation revealed that Akt was dephosphorylated at both Thr308 and Ser473 sites in infected cells. Further investigation demonstrated that ceramide was also responsible for the induction of PKCzeta, an atypical Ca-independent stress kinase, as well as the ceramide-activated protein phosphatases (e.g., protein phosphatase 2A [PP2A]). We found that Akt dephosphorylation was mediated by ceramide-induced PKCzeta-Akt association and PP2A activation. In addition, treatment of L. donovani-infected macrophages with PKCzeta-specific inhibitor peptide could restore the translocation of phosphorylated Akt to the cell membrane. This study also revealed that ceramide is involved in the inhibition of proinflammatory cytokine tumor necrosis factor alpha release by infected macrophages. These observations strongly suggest the importance of ceramide in the alteration of normal cellular functions, impairment of the kinase/phosphatase balance, and thereby establishment of leishmaniasis in the hostile macrophage environment.  相似文献   
26.
SMAD4 mutations found in unselected HHT patients   总被引:1,自引:0,他引:1  

Background

Hereditary haemorrhagic telangiectasia (HHT) is an autosomal dominant disease exhibiting multifocal vascular telangiectases and arteriovenous malformations. The majority of cases are caused by mutations in either the endoglin (ENG) or activin receptor‐like kinase 1 (ALK1, ACVRL1) genes; both members of the transforming growth factor (TGF)‐β pathway. Mutations in SMAD4, another TGF‐β pathway member, are seen in patients with the combined syndrome of juvenile polyposis (JP) and HHT (JP‐HHT).

Methods

We sought to determine if HHT patients without any apparent history of JP, who were undergoing routine diagnostic testing, would have mutations in SMAD4. We tested 30 unrelated HHT patients, all of whom had been referred for DNA based testing for HHT and were found to be negative for mutations in ENG and ALK1.

Results

Three of these people harboured mutations in SMAD4, a rate of 10% (3/30). The SMAD4 mutations were similar to those found in other patients with the JP‐HHT syndrome.

Conclusions

The identification of SMAD4 mutations in HHT patients without prior diagnosis of JP has significant and immediate clinical implications, as these people are likely to be at risk of having JP‐HHT with the associated increased risk of gastrointestinal cancer. We propose that routine DNA based testing for HHT should include SMAD4 for samples in which mutations in neither ENG nor ALK1 are identified. HHT patients with SMAD4 mutations should be screened for colonic and gastric polyps associated with JP.  相似文献   
27.
Hemophilia A (HEMA) is an X-linked bleeding disorder caused by mutations in the factor VIII gene (F8C). Molecular genetic testing for the factor VIII gene is challenging due to its large size. Here we present results of high throughput mutation scanning based on Southern blot analysis and direct sequencing of all PCR amplified coding exons and the exon-intron boundaries of the factor VIII gene. The results of mutation analysis on 89 hemophiliac males showed presence of a disease-causing mutation in 80 individuals (90%, 95% CI of 82%-95%). Seven out of nine mutation-negative individuals were severe cases of hemophilia A with < 1% factor VIII protein in the blood. The correlation of phenotype with genotype as observed in this study was not absolute. This finding is supported by similar observations in the international database for hemophilia A mutations (HAMSTeRS). This issue raises the importance of genotypes at other loci that can act as modifiers for the phenotype. Thirty-four novel mutations and three novel substitutions for previously reported amino acid residues were identified in this series of 80 mutations. The mutations cover the full spectrum including rearrangements, deletions, frameshift, and point mutations. The novel missense mutations require careful evaluation. Prediction of a mutation as the disease-causing allele was made from the nature of the substitution and the degree of conservation of the mutated amino acid among species that have diverged in evolution. In some cases segregation analysis of the mutation with disease condition was performed when other family members were available.  相似文献   
28.
Little is known about the experiences of individuals donating peripheral blood stem cells (PBSCs) or marrow for a second time. To study this, unrelated donors making a second donation through the National Marrow Donor Program between 2004 and 2013 were evaluated. Experiences of second-time donors giving marrow (n?=?118: first donation was PBSC in 76 and marrow in 42) were compared with those making only 1 marrow donation (n?=?5829). Experiences of second-time donors giving PBSCs (n?=?602) (first donation was PBSCs in 362; marrow in 240) were compared to first-time PBSC donors (n?=?16,095). For donors giving a second PBSC or marrow donation there were no significant differences in maximum skeletal pain, maximum symptoms measured by an established modified toxicity criteria, and recovery time compared with those who donated only once. Notably, the yield of marrow nucleated cells and PBSC CD34+ cells with second donations was less. As previously noted with single first-time donations, female (PBSCs and marrow) and obese donors (PBSCs) had higher skeletal pain and/or toxicity with a second donation. PBSC donors who experienced high levels of pain or toxicity with the first donation also experienced high levels of these symptoms with their second donation and slower recovery times. In conclusion, for most donors second donation experiences were similar to first donation experiences, but CD34+ yields were less. Knowledge of the donor's first experience and stem cell yields may help centers decide whether second donations are appropriate and institute measures to improve donor experiences.  相似文献   
29.
High-dose therapy (HDT) and autologous hematopoietic cell transplantation (auto-HCT) has been anecdotally prescribed in gray zone lymphoma (GZL), showing encouraging efficacy. We conducted a multicenter retrospective study aimed at assessing outcomes after auto-HCT in 32 patients with GZL treated at 9 transplantation centers in the United States. The median age of patients at transplantation was 38 years (range, 18 to 70 years), and the majority were male (n?=?21; 66%). The median number of lines of therapy before transplantation was 2 (range, 1 to 4). BEAM was the most commonly prescribed regimen (n?=?23; 72%). The median duration of follow-up for surviving patients was 34 months (range, 1 to 106 months). Median overall survival (OS) was not reached. The 3-year progression-free survival (PFS) and OS for all patients were 69% and 78%, respectively. Three-year PFS and OS were 100% for patients who received only 1 line of therapy before auto-HCT versus 65% (PFS, P?=?.25) and 75% (OS, P?=?.39) for those receiving >1 line. The cumulative incidence of relapse/progression was 4% at 1 year post-transplantation and 31% at 3 years post-transplantation. The 3-year nonrelapse mortality was 0%. These findings suggest that HDT and auto-HCT is an effective treatment in patients with GZL. Our findings ideally require confirmation in a larger cohort of patients, preferably in the setting of large prospective multicenter randomized controlled trials. However, we acknowledge that such studies could be difficult to conduct in patients with GZL owing to the disease's rarity. Alternatively, a multicenter prospective study that includes tissue banking and a data registry is warranted to help better understand the biology and natural history of the disease.  相似文献   
30.
The Revised International Staging System (R-ISS) and the International Myeloma Working Group 2014 (IMWG 2014) are newer staging systems used to prognosticate multiple myeloma (MM) outcomes. We hypothesized that these would provide better prognostic differentiation for newly diagnosed multiple myeloma (MM) compared with ISS. We analyzed the Center for International Blood and Marrow Transplant Research database from 2008 to 2014 to compare the 3 systems (N?=?628) among newly diagnosed MM patients undergoing upfront autologous hematopoietic cell transplantation (AHCT). The median follow-up of survivors was 48 (range, 3 to 99) months. The R-ISS provided the greatest differentiation between survival curves for each stage (for overall survival [OS], the differentiation was 1.74 using the R-ISS, 1.58 using ISS, and 1.60 using the IMWG 2014) . Univariate analyses at 3 years for OS showed R-ISS I at 88% (95% confidence interval [CI], 83% to 93%), II at 75% (95% CI, 70% to 80%), and III at 56% (95% CI, 3% to 69%; P < .001). An integrated Brier score function demonstrated the R-ISS had the best prediction for PFS, though all systems had similar prediction for OS. Among available systems, the R-ISS is the most optimal among available prognostic tools for newly diagnosed MM undergoing AHCT. We recommend that serum lactate dehydrogenase and cytogenetic data be performed on every MM patient at diagnosis to allow accurate prognostication.  相似文献   
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