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81.
82.
In Germany, long‐term commitment of surgeons to transplantation is rare. Most surgeons leave transplant surgery after a short stint and follow careers in other surgical fields. This rapid turnover of liver transplant surgeons may result in poor resource utilization and potentially compromise patient safety. In this report, we have analyzed the caseload and the careers of 25 surgeons in liver transplantation over a period of 22 years. The median time in liver transplantation was short. Of all surgeons who engaged in liver transplantation, the median time was 3.5 years. Surgeons who completed their training remained in the field for 7 years. Surgeons who prematurely stopped their training remained for 2 years. Individual total caseloads of transplant surgeons were relatively low. The median number of procedures was 40 for all surgeons, 153 for currently active surgeons, 51 for surgeons who completed training, 27 for surgeons currently in training, and a median of four liver transplantations for surgeons who prematurely stopped liver transplantation. The vast majority (75%) of surgeons prematurely quit liver transplantation to follow alternate surgical careers. Structural changes in academic transplant surgery have to be made to facilitate long‐term commitments of interested surgeons and to avoid “futile” transplant careers.  相似文献   
83.
Proximal row carpectomy (PRC) is an established surgical procedure used to treat post-traumatic osteoarthritis of the wrist with sparing of the midcarpal joint and advanced aseptic necrosis such as lunatomalacia. Proximalization of the distal carpal row following PRC may lead to secondary problems such as radiocarpal impingement. At follow-up, two of our patients complained about ulnar-sided wrist pain after proximal row carpectomy. Computed tomography (CT) scans were taken for both patients with an additional magnetic resonance imaging scan for one patient. The CT scan revealed clear osteolysis consistent with a pisiform bone impingement on the ulnar styloid process in both the cases, and also on the hamate in one patient. An impingement syndrome of this nature has not previously been described and should be kept in mind when patients report ulnocarpal symptoms after PRC.  相似文献   
84.

Purpose

Elevated T2-values of articular cartilage are associated with an increase in cartilage water that results from a damaged collagen matrix, and provide a marker for cartilage damage. We used T2 mapping to analyse the rim of cartilage defects that appeared to be intact on the morphological sequences, to determine whether there are early biochemical changes already present.

Method

We calculated T2 values for the rim of cartilage defects in 25 patients and compared these values to another area of control cartilage in these patients.

Results

A highly significant increase in T2 values of the deep, superficial, and global layer of the rim versus the control cartilage was measured. ANOVA showed a significant correlation of the defect levels with the T2 values of the deep and global zone of the adjacent cartilage tissue, but not with the superficial zone.

Conclusion

Although cartilage appears to be intact on morphological sequences, T2 mapping can show a loss of structural anisotropy of collagen and the associated increase in cartilage water that indicates the destruction of the adjacent cartilage. Preoperative information about the degree of damage of the collagen matrix will support decision making for cartilage repair.  相似文献   
85.
Background

The purpose of this consensus guideline is to outline recommendations for genetic testing that medical professionals can use to assess hereditary risk for breast cancer.

Methods

Literature review included large datasets, basic and clinical science publications, and recent updated national guidelines. Genetic testing to assess hereditary risk of cancer is a complex, broad, and dynamic area of medical research. The dominant focus of this guideline is limited in scope to breast cancer.

Results

There is a lack of consensus among experts regarding which genes among many should be tested in different clinical scenarios. There is also variation in the degree of consensus regarding the understanding of risk and appropriate clinical management of mutations in many genes.

Conclusions

Genetic testing should be made available to all patients with a personal history of breast cancer. Recent data are reviewed that support genetic testing being offered to each patient with breast cancer (newly diagnosed or with a personal history). If genetic testing is performed, such testing should include BRCA1/BRCA2 and PALB2, with other genes as appropriate for the clinical scenario and family history. For patients with newly diagnosed breast cancer, identification of a mutation may impact local treatment recommendations. Patients who had genetic testing previously may benefit from updated testing. Genetic testing should be made available to patients without a history of breast cancer who meet National Comprehensive Cancer Network guidelines. Finally, variants of uncertain significance are not clinically actionable and these patients should be managed based on their individual risk factors.

  相似文献   
86.
BackgroundCardiovascular complications are the leading causes of morbidity and mortality in patients with end-stage renal disease. The risk profile very often contributes to their death while on the waiting list. Most studies have been carried out in older patients with end-stage renal disease, reflecting the general dialysis population. The aim of this study was to analyze the risk profile in young patients with advanced chronic kidney disease on the kidney transplant waiting list.MethodsThis was a retrospective, single-center study of 748 patients on the kidney transplant waiting list at the University Hospital Essen, Germany. Clinical and laboratory parameters were collected between 2015 and 2016.ResultsOf 748 patients (62% male), the median age was 48 years. Hypertension, coronary heart disease, and diabetes mellitus were the leading comorbidities, and their frequency rose significantly with age. Their median laboratory values did not differ significantly depending on age except for albumin. Hyperuricemia was quite common in our population with a prevalence of about 75% in women and 50% in men throughout all age groups. A total of 26.6% of the patients between 18 and 35 years of age had advanced anemia (hemoglobin < 10 g/dL), and thus they were affected most frequently. Elevated C-reactive protein serum levels were observed in 37.2% of the patients. Regarding the lipid profile, we observed that HDL cholesterol was within the normal range in only among 51.9% of men and 44.3% of women.ConclusionsCardiovascular risk factors are quite common in our cohort and affect young patients similarly.  相似文献   
87.
88.
BACKGROUND: Reactive oxygen species play a major role in the development of endothelial dysfunction. It is as yet unspecified whether increased oxidative stress contributes to endothelial dysfunction of the renal vasculature in patients with type 2 diabetes. METHODS: Renal haemodynamics were studied in 20 patients with type 2 diabetes and arterial hypertension (age 62 +/- 5 years) and 20 non-diabetic hypertensive patients at baseline and following infusions of the nitric oxide synthase inhibitor, N(G)-monomethyl-L-arginine (L-NMMA; 4.25 mg/kg); the substrate of nitric oxide synthase, L-arginine (100 mg/kg); and the antioxidant, vitamin C (3 g, co-infused with L-arginine 100 mg/kg). RESULTS: The response of renal plasma flow (RPF) to L-NMMA (-54 +/- 62 and -45 +/- 42 ml/min/1.73 m(2); P = NS) and L-arginine (+46 +/- 36 and +49 +/- 25 ml/min/1.73 m(2); P = NS) was not different between diabetic and non-diabetic patients. In contrast, vitamin C induced a more pronounced increase in RPF in diabetic than in non-diabetic patients when co-infused with L-arginine (+71+/-47 and +43+/-33 ml/min/1.73 m(2); P<0.05). CONCLUSIONS: The difference in the response of renal perfusion to an antioxidant suggests increased formation of reactive oxygen species and thereby reduced nitric oxide bioavailability in the renal vasculature of patients with type 2 diabetes.  相似文献   
89.
PURPOSE: To acquire the center of k-space while extending three-dimensional free-breathing navigator-gated coronary magnetic resonance (MR) angiography by an initial single breath-hold. MATERIALS and METHODS: This approach was successfully applied in eight healthy adult subjects. Resulting images were compared with conventionally acquired free-breathing navigator-gated MR angiograms. RESULTS: The acquisition of k-space center during the single breath-hold resulted in a 26% increase (P < 0.05) of signal-to-noise ratio. Visible length of the right coronary artery, as well as contrast-to-noise ratio between the blood and the myocardial muscle, were identical. CONCLUSION: The breath-hold extension was shown to be a valuable technique that may be combined with first-pass contrast-enhanced MR imaging.  相似文献   
90.
BACKGROUND: The aim of this single-center study was to investigate whether trough level adjusted mycophenolate mofetil (MMF) is more efficacious in combination with tacrolimus (TAC) or cyclosporine (CsA) and to evaluate the impact of either drug on MMF dosage. METHODS: Sixty patients (TAC, n = 30; CsA, n = 30) undergoing heart transplantation were randomized into a prospective, open-label, controlled trial. Immunosuppression consisted of TAC or CsA in combination with MMF and corticosteroids. Target blood trough levels of TAC, CsA, and mycophenolic acid (MPA) were in the range of 10 to 15 ng/mL, 100 to 300 ng/mL, and 1.5 to 4.0 microg/mL, respectively. Acute rejection episodes (ARE); survival data; and adverse events with a special emphasis on infections, diabetes, hypertension, hypercholesterolemia, and the development of graft vessel disease (GVD) were recorded. RESULTS: Baseline characteristics were well balanced. All patients were successfully withdrawn from corticosteroids within 6 months of transplant. Freedom from acute rejection was significantly higher (P = 0.0001) and the incidence of ARE per 100 patient days significantly lower in the TAC-MMF group than in the CsA-MMF group (0.03 vs. 0.15; P = 0.00007). Overall patient survival during follow-up was similar (93% vs. 90%). To achieve the targeted MPA blood levels, a significantly lower dose of MMF was required for TAC versus CsA patients. After a follow-up time of 2 years, the mean GVD score was 1.85 +/- 3.18 in the TAC-MMF group and 3.95 +/- 4.8 in the CsA-MMF group (P = 0.08). CONCLUSIONS: At the selected doses and target levels for TAC and CsA used in this study, trough level adjusted MMF was more efficacious in combination with TAC for prevention of ARE. Furthermore, CsA patients need significantly more MMF to achieve similar MPA levels.  相似文献   
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