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51.
干细胞移植与心脏疾病治疗   总被引:1,自引:0,他引:1  
干细胞是一类具有自我更新能力和分化潜能的细胞,在临床上应用干细胞移植技术可治疗心脏疾病,主要应用于急性心肌梗死、扩张型心肌病和心脏的起搏治疗。干细胞移植的主要途径包括经外周静脉注射、经冠状动脉注射、心内膜注射、经心外膜直视注射及干细胞自体动员。此项技术的开展使临床获益很大,但同时也存在一些问题亟待解决,如移植的安全性、移植细胞数量的选择、移植后的评价问题等。该学科尚在进一步发展中。  相似文献   
52.
Women with cardiac disease constitute a growing percentage of parturients, and in many series cardiac disease is the leading cause of maternal mortality. Involvement of anesthesiologists in the planning for and management of delivery in these women can improve the experience and potentially the outcome of these patients. Communication with the anesthesiology team about particularly complex cases is essential to avoid both medical complications and inter-disciplinary disagreements. The specific role and contributions of the anesthesiology team will depend significantly on the nature of the institution and the organization of the (obstetric) anesthesiology service.  相似文献   
53.
中国佛教禅宗书法艺术,风采独特,其书学著述,丰富多彩.综观禅宗书学著述,可以清楚地看到,“写经”是禅家所从事的书法艺术创作活动,是禅家特别关注和讨论的重要话题之一.僧人通过写经,宏扬教义、传播佛法、善行佛事、参禅悟道,乃是“栖身大乘”,“游戏翰墨,作大佛事”.禅宗书学著述从一个特殊的视角,论述了写经的重要意义、巨大功德、书写宗旨、价值取向、艺术特点、特殊形态.  相似文献   
54.
A growth factor specific for epithelial cells was identified in conditioned medium of a human embryonic lung fibroblast cell line. The factor, provisionally termed keratinocyte growth factor (KGF) because of its predominant activity on this cell type, was purified to homogeneity by a combination of ultrafiltration, heparin-Sepharose affinity chromatography, and hydrophobic chromatography on a C4 reversed-phase HPLC column. KGF was both acid and heat labile and consisted of a single polypeptide chain of approximately 28 kDa. Purified KGF was a potent mitogen for epithelial cells, capable of stimulating DNA synthesis in quiescent BALB/MK epidermal keratinocytes by greater than 500-fold with activity detectable at 0.1 nM and maximal at 1.0 nM. Lack of mitogenic activity on either fibroblasts or endothelial cells indicated that KGF possessed a target cell specificity distinct from any previously characterized growth factor. Microsequencing revealed an amino-terminal sequence containing no significant homology to any known protein. The release of this growth factor by human embryonic fibroblasts raises the possibility that KGF may play a role in mesenchymal stimulation of normal epithelial cell proliferation.  相似文献   
55.

Background

The timing of transplant listing after implantation of a left ventricular assist device (LVAD) remains uncertain, given high device complication rates and apparent stability of some LVAD-supported patients. This investigation quantifies the effect of delayed transplant listing and transplantation rates on medium-term survival and LVAD complications.

Methods and Results

A Markov model was used to simulate the effects of delaying initial transplant listing after LVAD implantation. Modeled parameters were derived from the Standard Transplant Analysis and Research file. When transplant listing was delayed and 5-year results were examined, fewer persons underwent transplantation (53% in base model vs 51% in 180-day-delay model) and the fraction of deaths while waiting increased (17% in base model vs 21% in 180-day delay model). Life expectancy changed minimally from the base model (3.50 y) when initial listing was delayed by 180 days (3.51 y).

Conclusions

Delaying initial transplant listing increased the likelihood of death while waiting for a transplant and decreased the likelihood of transplantation. In aggregate, life expectancy was unchanged by delays in listing. This study suggests that delaying transplant listing with the expectation of providing additional life expectancy is not likely with current LVAD technology.  相似文献   
56.
Between June 1989 and June 1992, 144 patients participated in sequential clinical trials using peripheral blood progenitor cells (PBC) as their sole source of hematopoietic rescue following high-dose chemotherapy. All patients had received prior extensive combination chemotherapy and had marrow defects that precluded autologous bone marrow transplantation (ABMT). PBC were collected according to a single apheresis protocol. The initial 86 patients (group 1) had PBC collected without mobilization. Beginning in April 1991, PBC were mobilized solely with recombinant human granulocyte-macrophage colony-stimulating factor (rHuGM-CSF). Thirty-four patients (group 2) received rHuGM-CSF at a dose of 125 micrograms/m2/d by continuous intravenous infusion, and 24 patients (group 3) received rHuGM-CSF at a dose of 250 micrograms/m2/d by continuous intravenous infusion. Patients underwent at least six aphereses and had a minimum of 6.5 x 10(8) mononuclear cells (MNC)/kg collected. Cytokines were not routinely administered immediately after transplantation. A median of nine aphereses were required to collect PBC in group 1 and seven aphereses for groups 2 and 3 (P = .03). The time required to recover 0.5 x 10(9)/L granulocytes after transplant was significantly shorter (P = .0004) for the mobilized groups; the median time to recovery was 26 days for group 1, 23 days for group 2, and 18 days for group 3. Transplantation of PBC mobilized with rHuGM-CSF resulted in a shorter time to platelet (P = .04) and red blood cell (P = .01) transfusion independence. Mobilization with rHuGM-CSF alone resulted in efficient collection of PBC, that provided rapid and sustained restoration of hematopoietic function following high-dose chemotherapy. Mobilization of PBC with rHuGM-CSF alone is an effective method for patients who have received prior chemotherapy and have bone marrow abnormalities.  相似文献   
57.
OBJECTIVE: ATP-sensitive K+ channels have been classified based on their inhibition by cytoplasmic ATP. Recent evidence in vascular smooth muscle has suggested that these channels show weak sensitivity to intracellular ATP. However, it is not known whether these channels regulate the resting K+ conductance in vascular smooth muscles. Therefore, the aim of the present investigation was to characterize this current in rat aorta myocytes and to examine whether it contributes to setting the membrane potential. METHODS: The conventional and nystatin-permeablised whole cell patch clamp techniques were used to characterize the effect of glibenclamide on membrane potential and K+ current in enzymatically dispersed rat aorta myocytes. RESULTS: The mean resting potential measured in current clamp mode using the permeabilized patch approach was -54 +/- 5 mV (n = 8). Glibenclamide (10 microM) caused a reversible 24-mV depolarization in these cells. In symmetrical K+ (135 mM) solution an inward glibenclamide-sensitive (10 microM) current (-4.1 +/- 0.7 pA/pF; n = 5), hereafter termed Iglib, was observed at a membrane potential of -80 mV when cells held at -60 mV were ramped from -80 to +80 mV. In the absence of any nucleotide in the pipette solution, Iglib measured by the conventional whole-cell method was -23.69 +/- 4.65 pA/pF (n = 9). With 1 and 3 mM ATP in the pipette, the average current density was -25 +/- 6.3 pA/pF (n = 8), and -9.4 +/- 2.7 pA/pF (n = 9), respectively. In the absence of ATP, 1 mM GDP significantly (P < 0.01) increased Iglib (-44.8 +/- 8.4 pA/pF; n = 13). Inclusion of 1 mM ATP in the GDP-containing pipette solution had no significant effect on the current amplitude (-56.4 +/- 10.7 pA/pF; n = 7). Iglib fell to -11.0 +/- 2.9 pA/pF (n = 10) if 1 mM GDP and 3 mM ATP were present. In symmetrical K+, the Iglib observed in the presence of 1 mM ATP in the pipette was increased by more than two-fold in the presence of 10 microM levcromakalim. In PSS containing 5 mM K+, a significant glibenclamide-sensitive current was observed at -45 mV membrane potential when cells dialyzed with 1 mM ATP were ramped between -80 to 30 mV. CONCLUSION: These results demonstrate that Iglib channels in rat aorta myocytes differ from classical KATP channels, being relatively insensitive to intracellular ATP. Iglib therefore appears to have an important role in contributing to the maintenance of the resting potential in rat aortic smooth muscle.  相似文献   
58.
59.

Background

A high prevalence of tuberculosis (TB) among HIV‐positive injecting drug users (IDUs) may fuel the TB epidemic in the general population of Romania. We determined the frequency and characteristics of TB in HIV‐infected IDUs referred to a national centre.

Methods

Prospective observational cohort study of all newly‐diagnosed HIV‐positive IDUs admitted to Victor Babes Hospital, Bucharest, between January 2009 and December 2014. Socio‐demographics, clinical characteristics and outcomes of HIV/TB co‐infected IDUs were compared to HIV‐positive IDUs without TB.

Results

170/598 (28.5%) HIV‐infected IDUs were diagnosed with TB. The prevalence increased from 12.5% in 2009 to 32.1% in 2014 (P < 0.001). HIV/TB co‐infected individuals had lower median CD4 cell counts 75 (vs. 450/mm3, P < 0.0001) and higher median HIV viral loads 5.6 log10 (vs. 4.9 log10, P < 0.0001) when presenting to healthcare services. 103/170 (60.6%) HIV/TB co‐infected IDUs were diagnosed with pulmonary TB. Resistant Mycobacterium tuberculosis strains were common, with 18/105 (17.1%) of patients having Multi‐Drug Resistant (MDR) disease. Higher mortality rate was associated with TB co‐infection (P < 0.0001), extra‐pulmonary TB (P = 0.0026) and extensively drug resistant TB (P = 0.024).

Conclusions

Tuberculosis (TB) is an increasing problem in HIV‐infected IDUs in Romania. Presentation is often with advanced HIV, significant TB drug resistance and consequent outcomes are poor.
  相似文献   
60.

Background

The Association of American Medical Colleges (AAMC) includes the ability to collaborate in an interprofessional team as a core professional activity that trainees should be able to complete on day 1 of residency (Med Sci Educ. 26:797–800, 2016). The training that medical students require in order to achieve this competency, however, is not well established (Med Sci Educ. 26:457–61, 2016), and few studies have examined non-physician healthcare professionals’ perspectives regarding resident physicians’ interprofessional skills.

Objective

This study aims to describe non-physicians’ views on barriers to collaboration with physicians, as well as factors that contribute to good collaborative relationships.

Participants

Nurses, social workers, case managers, dietitians, rehabilitation therapists, and pharmacists at one academic medical center, largely working in the inpatient setting.

Approach

A qualitative study design was employed. Data were collected from individual interviews and focus groups comprising non-physician healthcare professionals.

Key Results

Knowledge gaps identified as impeding interprofessional collaboration included inadequate understanding of current roles, potential roles, and processes for non-physician healthcare professionals. Specific physician behaviors that were identified as contributing to good collaborative relationships included mutual support such as backing up other team members and prioritizing multidisciplinary rounds, and communication including keeping team members informed, asking for their input, physicians explaining their rationale, and practicing joint problem-solving with non-physicians.

Conclusions

Discussion of how physician trainees can best learn to collaborate as members of an interprofessional team must include non-physician perspectives. Training designed to provide medical students and residents with a better understanding of non-physician roles and to enhance mutual support and communication skills may be critical in achieving the AAMC’s goals of making physicians effective members of interprofessional teams, and thus improving patient-centered care. We hope that medical educators will include these areas identified as important by non-physicians in targeted team training for their learners.
  相似文献   
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