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51.

Background

Neglected femoral neck fracture in young adults is an intriguing problem. This retrospective study tried to solve that challenge through open reduction, cannulated screw internal fixation, autogenous iliac bone and bone marrow grafting.

Methods

Thirty-six cases were studied; they were classified according to Sandhu et al.'s classification. Twenty cases were type I and 16 cases were type II fractures; the mean age was 26.8 years; fracture neglect averaged 44.6 days. Twenty cases had posterior comminution and 16 cases had anterior comminution. All cases had open reduction, cannulated screw internal fixation, autogenous iliac bone and bone marrow grafting. The Harris hip score and Matta et al. grading system were applied for functional and radiological evaluation, respectively.

Results

The average postoperative follow-up was 25.3 months; 94.4 % of the cases had solid union in a mean of 19.6 weeks. Functionally, the Harris hip score averaged 87.8 points. Nonunion, avascular necrosis and coxa vara complicated two, two and four cases, respectively. Fair and poor radiological results were related to coxa vara and avascular necrosis, respectively. Nonunion was significantly related to posterior comminution, type II neglected fracture, and a neglect of more than 45 days. Age groups more than 30 years old and postoperative neck-shaft angles <140° were significantly associated with late-onset radiological healing and nonunion.

Conclusions

Cannulated screw osteosynthesis augmented by autogenous bone and bone marrow grafting is a simple, easy-to-perform surgical procedure with encouraging clinical outcomes for selected patients complaining of that difficult problem.  相似文献   
52.
Hypercalcemia can result from excessive bone resorption, renal calcium retention, excessive intestinal calcium absorption, or a combination of these conditions. Hypercalcemia may also provoke acute renal failure (ARF) or hypertension, or aggravate the tubular necrosis that is frequently found in cases of ARF. The association of ARF and hypercalcemia was studied retrospectively in eight patients based in the data in their charts. Data are expressed as median and percentile (25th; 75th). Our results show that ARF associated with hypercalcemia was related with comorbidity in all cases (cancer, multiple myeloma, hyperparathyroidism, sarcoidosis, vitamin D intoxication, and leprosy). Maximum median serum creatinine levels were 3.3 mg/dL (2.7, 3.8 mg/dL) before treatment and 1.1 mg/dL (0.9, 1.3 mg/dL) after treatment. Maximum total median serum calcium was 15.9 mg/dL (13.5, 19.8 mg/dL) before treatment and 9.1 mg/dL (8.4, 9.7 mg/dL) after treatment. Maximum median ionized serum calcium was 2.1 mmol/L (1.8, 2.2 mmol/L) before treatment and 1.1 mmol/L (1.0, 1.2 mmol/L) after treatment. Different kinds of treatment induced a rapid fall in serum calcium concentration. All patients were treated with hydration and diuretics, and three patients also received calcitonin. Serum creatinine concentration always fell simultaneously with the decrease in serum calcium in all cases. All patients progressed with nonoliguric renal failure. In conclusion, in ARF, patients are frequently hypocalcemic. Usually, the presence of hypercalcemia associated with ARF is indicative of the presence of comorbidity, as observed in all eight patients studied here. There was an improvement of renal function in all cases as serum calcium levels decreased.  相似文献   
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Karam  Mohamad  Ghanem  Ismat  Vergari  Claudio  Khalil  Nour  Saadé  Maria  Chaaya  Céline  Rteil  Ali  Ayoub  Elma  Saad  Eddy  Kharrat  Khalil  Skalli  Wafa  Assi  Ayman 《European spine journal》2022,31(9):2326-2338
European Spine Journal - To evaluate the global alignment of non-operated subjects with adolescent idiopathic scoliosis. A total of 254 subjects with AIS and 64 controls underwent low dose biplanar...  相似文献   
56.
57.

Background

We describe the case of a 57-year-old woman who developed right heart failure after a second orthotopic bicaval cardiac transplant.

Case Report

Perioperative transesophageal echocardiogram showed a left atrial mass consisting of redundant tissue at the atrial suture line in the left atrium that did not have a significant hemodynamic effect under general anesthesia.

Conclusions

After discharge from the intensive care unit, she developed right heart failure that required excision and left atrial patch augmentation.  相似文献   
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Solary  E; Bertrand  R; Kohn  KW; Pommier  Y 《Blood》1993,81(5):1359-1368
The effects of monocytic/macrophage and granulocytic differentiation induced by phorbol myristate acetate (TPA) and all-trans retinoic acid, respectively, were tested on the induction of apoptosis in human promyelocytic leukemia HL-60 cells treated with topoisomerase I and II inhibitors. Using a filter-binding assay, we observed a strong inhibition of DNA fragmentation induced by 3- and 24-hour continuous exposure to camptothecin, VP-16, VM-26, and m-AMSA in TPA- differentiated cells. The inhibition of the typical internucleosomal DNA fragmentation was confirmed by agarose gel electrophoresis. By contrast, drug-induced DNA fragmentation was not inhibited in retinoic acid-differentiated cells, and apoptosis occurred in these cells after 4 to 5 days in the absence of drug treatment. The TPA inhibitory effect was maximal after 24 hours of treatment and was correlated with differentiation, because phorbol dibutyrate ester was active, whereas 4- alpha-TPA, a nontumor promoter that does not induce differentiation, was not active. Using alkaline elution, we observed that TPA and retinoic acid differentiation were associated with changes in topoisomerase-mediated DNA breaks that were not correlated with their differential effects on drug-induced DNA fragmentation. Moreover, TPA also inhibited DNA fragmentation induced by vinblastine, cycloheximide, calphostin C, and x-rays. Using a cell-free system, we observed that DNA fragmentation was not inhibited in nuclei from TPA-differentiated cells. Rather, inhibition of apoptosis seemed to take place in the cytoplasm. We conclude that phenotypic changes associated with TPA- induced differentiation include inactivation of a cytoplasmic activity that can induce DNA fragmentation associated with apoptosis.  相似文献   
60.
Primary cilia are present on mammalian neurons and glia, but their function is largely unknown. We generated conditional homozygous mutant mice for a gene we termed Stumpy. Mutants lack cilia and have conspicuous abnormalities in postnatally developing brain regions, including a hypoplasic hippocampus characterized by a primary deficiency in neural stem cells known as astrocyte-like neural precursors (ALNPs). Previous studies suggested that primary cilia mediate sonic hedgehog (Shh) signaling. Here, we find that loss of ALNP cilia leads to abrogated Shh activity, increased cell cycle exit, and morphological abnormalities in ALNPs. Processing of Gli3, a mediator of Shh signaling, is also altered in the absence of cilia. Further, key mediators of the Shh pathway localize to ALNP cilia. Thus, selective targeting of Shh machinery to primary cilia confers to ALNPs the ability to differentially respond to Shh mitogenic signals compared to neighboring cells. Our data suggest these organelles are cellular “antennae” critically required to modulate ALNP behavior.  相似文献   
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