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This study explores the mutual influences of friendship development and organizational assimilation processes among first-year male medical students. Interviews and observations were used to examine the ways students constructed and enacted their friendships with male classmates during the process of assimilating into medical school. The study also examined how the male friends viewed the influence of their friendships on their assimilation into medical school and how the assimilation process simultaneously influenced their developing friendships. Thematic analysis revealed that although the men perceived their medical school friendships as "not yet close," the friendships provided them with valuable tangible and socio-emotional support during the rigorous assimilation process and that the assimilation process paradoxically facilitated as well as hindered the development of friendships. Implications for practice and future research are discussed.  相似文献   
85.
Sarcoidosis is frequently associated with elevations of serum levels of either lysozyme or angiotensin-converting enzyme or both. Elevation of serum lysozyme probably derives from increased monocyte secretion of lysozyme and from increases in the lysozyme activity of the lung macrophage. Human alveolar macrophages from sarcoidosis patients contain more angiotensin-converting enzyme than normal human alveolar macrophages. The pathogenetic, diagnostic and therapeutic significance of these observations are discussed.  相似文献   
86.
Computed tomographic appearance of the bulging annulus   总被引:6,自引:0,他引:6  
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87.
OBJECTIVE: To evaluate the rate of multiple pregnancies in intrauterine insemination cycles stimulated with a minimal dose of recombinant follicle stimulating hormone (rec-FSH). DESIGN: Retrospective study. SETTING: University Medical Center. POPULATION: A total of 1256 patients underwent 3219 consequent intrauterine insemination cycles with minimal ovarian stimulation. METHODS: Patients received 50 or 75 IU of rec-FSH from day four to day seven. The dose was adjusted according to oestradiol (E(2)) levels in order to achieve a maximum of two follicles on the day of hCG administration. MAIN OUTCOME MEASURES: Peak E(2) levels, the number of follicles >15 mm and pregnancy rates were calculated. The predictive value of E(2) levels for multiple gestations was also estimated. RESULTS: Of 3219 cycles, 334 resulted in pregnancies (10%). Of these, 238 (91%) were singletons, 28 (8%) twins and 1 (0.3%) was a triplet. The cumulative overall pregnancy rate was 43%. Patients over 40 years old had a significantly lower pregnancy rate per cycle and overall live birth rate (P < 0.05). Most pregnancies (83%) occurred during the first three cycles. Pregnancy rates per cycle varied from 8% for tubal factor to 14% for anovulation infertility. CONCLUSIONS: Minimal FSH stimulation in intrauterine insemination cycles may reduce the rates of twins and high order multiple pregnancies without affecting overall pregnancy rates.  相似文献   
88.
Peri-operative myocardial ischaemia is the single most important risk factor for an adverse cardiac outcome after non-cardiac surgery. The present study examines whether intermittent 12-lead ECG recordings can be used as an early warning tool to identify patients suffering from peri-operative myocardial ischaemia and subsequent myocardial cell damage. Fifty-five vascular surgery patients at risk for or with a history of coronary artery disease were monitored for peri-operative myocardial ischaemia using intermittent 12-lead ECG recordings taken pre-operatively and at 15 min, 20 h, 48 h, 72 h and 84 h postoperatively. The effectiveness of the 12-lead ECG was gauged by examining concordance with continuous 3-channel Holter monitoring and capturing peri-operative myocardial ischaemia by serial analyses of creatine kinase myocardial band isoenzyme and cardiac troponin T and I. The incidence of peri-operative myocardial ischaemia detected by 12-lead ECG was 44% and was identifiable in most patients (88%) 15 min after surgery. The incidence of peri-operative myocardial ischaemia detected by continuous monitoring was 53%, with the most severe episodes occurring intra-operatively and during emergence from anaesthesia. The concordance of the 12-lead method with continuous monitoring was 72%. The concordance of creatine kinase myocardial band isoenzyme activity with the 12-lead method was 71% and with Holter monitoring 57%. The concordance of mass concentration of creatine kinase myocardial band with 12-lead ECG recordings was 75%, and the corresponding value for Holter monitoring was 68%. The concordance of cardiac troponin T and I levels with the 12-lead method was 85% and 87%, respectively, and concordance with Holter monitoring was 72% and 66%, respectively. The postoperative 12-lead ECG identified peri-operative myocardial ischaemia associated with subsequent myocardial cell damage in most patients undergoing vascular surgery.  相似文献   
89.

Background

The association between intravascular ultrasound (IVUS) signs of plaque instability and plasma levels of biomarkers was determined in patients with unstable angina and non-ST-segment elevation myocardial infarction (UA/NSTEMI).

Methods

Fifty-two patients underwent coronary angiography and IVUS 8 ± 5 hours after the onset of chest pain. IVUS analysis included plaque morphology, disruption, thrombi and eccentricity, lumen, external elastic membrane, and plaque plus media areas of culprit lesion and reference segments and arterial remodeling. Plasma levels of the thrombin activation system (thrombin-antithrombin complex [TAT], tissue factor pathway inhibitor [TFPI], and prothrombin fragments 1+2 [F1+2]) and plasmin activation system (tissue and urokinase-type plasminogen activator [t-PA and u-PA], plasminogen activator inhibitor-1 [PAI-1], and D-dimer) were measured with enzyme-linked immunosorbent assay kits before angiography.

Results

Elevated levels of TAT (7.2 ± 6.0 μg/L), F1+2 (1.8 ± 1.0 nmol/L), TFPI (179.1 ± 131.0 ng/mL), PAI-1 (95.4 ± 54.6 ng/mL), t-PA (10.6 ± 8.8 ng/mL), and u-PA (2.6 ± 0.9 ng/mL) were found in patients with UA/NSTEMI. The serum levels of D-dimer (40.0 ± 39.5 ng/mL) remained in reference range. Expansive and constrictive remodeling were found in 18 (35%) and 12 (23%) patients, respectively. Expansive remodeling of the culprit lesion was associated with significantly higher plasma levels of PAI-1 (121.6 ± 55.0 vs 87.7 ± 61.5 and 77.4 ± 42.8 ng/ml, P = .039), and u-PA (3.0 ± 1.2 vs 2.2 ± 0.5 and 2.5 ± 0.7 ng/mL, P = .026) as compared with constrictive and neutral remodeling. Increased plasma levels of u-PA were associated with plaque rupture (3.0 ± 0.7 vs 2.5 ± 0.9 ng/mL, P = .062). Plasma levels of PAI-1 and u-PA correlated positively with plaque plus media (P = .0297 and P = .0093) and external elastic membrane areas (P = .010 and P = .0002).

Conclusions

Elevated levels of biomarkers of plasmin activation system are associated with signs of plaque instability of culprit lesion in UA/NSTEMI and might therefore serve as non-invasive determinants of the population that is at high risk for subsequent adverse events.  相似文献   
90.
Storytelling is an approach to teaching and learning that develops from the lived experiences ofteachers, clinicians, and students. This article examines thestorytelling process used to help students explore personal roles and make sense of their lives, and as an approach to help diverse undergraduate students with various learning styles.  相似文献   
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