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排序方式: 共有8142条查询结果,搜索用时 15 毫秒
51.
Medina-Franco H Soto-Germes S Ulloa-Gómez JL Romero-Trejo C Uribe N Ramirez-Alvarado CA Robles-Vidal C 《Annals of surgical oncology》2008,15(6):1689-1695
Background Local ablative therapy of breast cancer represents the next frontier in the minimally invasive breast-conservation treatment.
We conducted a phase II trial to evaluate radiofrequency ablation (RFA) of invasive breast carcinomas.
Methods Consecutive patients from two Mexican Institutions with invasive breast cancers < 4 cm, with no multicentric tumors and no
previous chemotherapy were included in this trial. Under ultrasound guidance, the tumor and a 5 mm margin of surrounding breast
tissue were ablated with saline-cooled RFA electrode followed by surgical resection. Routine pathologic analysis and viability
evaluation with NADPH-diaphorase stain were performed to assess tumor ablation. Procedure-associated morbidity was recorded.
Results Twenty-five patients were included. Mean patient age was 55.3 years (range 42–89 years). Mean tumor size was 2.08 cm (range
0.9–3.8 cm). Fourteen tumors (56%) were <2 cm. The mean ablation time was 11 minutes using a mean power of 35 W. During ablation,
the tumors become progressively echogenic that corresponded with the region of severe RFA injury at pathologic examination.
Of the 25 patients treated, NADPH stain showed no evidence of viable malignant cells in 19 patients (76%), with significant
difference between tumors <2 cm (complete necrosis in 13 of 14 cases, 92.8%) vs. those >2 cm (complete necrosis 6 of 11 cases,
54.5%) (P < .05). No significant morbidity was recorded.
Conclusions RFA is a promising minimally invasive treatment of small breast carcinomas, as it can achieve effective cell killing with
a low complication rate. Further studies are necessary to optimize the technique and evaluate its future role as local therapy
for breast cancer. 相似文献
52.
Anti-LFA-1 improves pig islet xenograft function in diabetic mice when long-term acceptance is induced by CTLA4Ig/anti-CD40L 总被引:1,自引:0,他引:1
Kumagai-Braesch M Ekberg H Wang F Osterholm C Ehrnfelt C Sharma A Lindeborg E Holgersson J Corbascio M 《Transplantation》2007,83(9):1259-1267
BACKGROUND: It has been previously demonstrated that addition of anti-LFA-1 to a combination of CTLA4Ig and anti-CD40L induces the permanent acceptance of dopaminergic fetal pig xenografts when transplanted into the brain of wild-type mice. The purpose of this study was to test whether this costimulation blockade also can induce acceptance of adult pig islets transplanted to C57BL/6 mice with streptozotocin-induced diabetes. METHODS: Recipients were treated with CTLA4Ig/anti-CD40L+/-anti-LFA-1 or isotype control antibodies during the first week after transplantation. Half of the costimulation blockade-treated recipients had their grafts removed after 8 weeks. The other half was observed up to 5 months. RESULTS: Recipients treated with CTLA4Ig/anti-CD40L/anti-LFA-1 had significantly lower blood glucose and gained more weight than CTLA4Ig/anti-CD40L-treated recipients. CTLA4Ig/anti-CD40L-treated recipients exhibited unstable blood glucose. IPGTT of these recipients revealed a slow recovery to normal blood glucose levels at week 4. In comparison, CTLA4Ig/anti-CD40L/anti-LFA-1 treated recipients exhibited a significantly superior glucose clearance. CTLA4Ig/anti-CD40L+/-anti-LFA-1 treated recipients did not produce anti-pig IgG, whereas control antibody-treated mice did. CD4+ T cells from costimulation blockade-treated recipients proliferated less than CD4+ T cells from control antibody-treated mice when co-cultured with syngeneic antigen presenting cells loaded with pig islet antigens. CONCLUSIONS: CTLA4Ig/anti-CD40L/anti-LFA-1-treated recipients had superior islet function compared with CTLA4Ig/anti-CD40L-treated recipients. However, both costimulation blockade regimens led to islet graft acceptance up to 5 months after a 1-week treatment. 相似文献
53.
Joyce Stoelting Linda McKenna Elizabeth Taggart Rosalie Mottar Brenda Recchia Jeffers M Cecilia Wendler 《Journal of wound, ostomy, and continence nursing》2007,34(4):382-388
Nosocomial pressure ulcers (PU) occur in approximately 12% of all hospitalized patients. The risk can be determined by a variety of intrinsic and extrinsic factors. As a first line of defense against nosocomial PU, we use the Braden Scale to determine the potential risk of PU development during hospitalization. Once risk was identified, our standard was to implement an individualized plan of care. However, consistent implementation of PU preventative measures was lacking. As a result, a process improvement project was developed and implemented. The purpose of this process improvement project was to increase communication about and awareness of the need to vigorously intervene and document whenever there is risk of, or development of, a nosocomial PU. By initiating consistent use of a PU Tracking Form, developing unit-based wound champions that serve as experts in ulcer prevention, and creating an individual case analysis process, PU prevention and tracking was institutionalized. Results indicate that our nosocomial PU rate has declined from 7% to 4%. 相似文献
54.
Nicola Lopomo Cecilia Signorelli Tommaso Bonanzinga Giulio Maria Marcheggiani Muccioli Maria Pia Neri Andrea Visani Maurilio Marcacci Stefano Zaffagnini 《International orthopaedics》2014,38(6):1167-1172
Purpose
Despite the overall success of the surgical anterior cruciate ligament (ACL) reconstruction, some patients still present with instability symptoms even after the surgery, mainly due to the presence of associated lesions. At present, the pivot shift test has been reported to be the benchmark to assess rotatory knee laxity. The purpose of this study was to quantitatively evaluate rotatory knee laxity at time-zero in order to determine whether detected post-reconstruction laxity was predictable by its value measured before the reconstruction, which was hypothized to be influenced by the presence of associated lesions.Methods
Rotatory knee laxity was retrospectively analysed in 42 patients, including two different ACL reconstructions. The maximal anterior displacement and the absolute value of the posterior acceleration reached during the reduction of the tibial lateral compartment were intra-operatively acquired by using a navigation system and identified as discriminating parameters. For each parameter, statistical linear regression analysis (line slope and intercept) was performed between pre- and post-reconstruction values.Results
No statistically significant influence of the initial posterior acceleration on the post-reconstruction outcome was found (line slope, p > 0.05), although a statistically significant line intercept was indeed identified (p < 0.001). A statistically significant influence on the surgery outcome was instead found for the initial value of the anterior tibial displacement (line slope = 0.39, p = 0.004), meaning that, on average, about 40 % of the post-reconstruction lateral compartment displacement could be explained by the corresponding pre-reconstruction value. Both of these findings highlighted the importance of intra-operative quantification of rotatory knee laxity to identify correct indications for the surgery.Conclusions
This study provided important implications for the future possibility of defining a quantifying tool able to assess rotatory knee laxity during ACL reconstruction. This could allow detection of additional injuries to secondary restraints by easily performing rotatory knee laxity tests, which in turn could reduce post-surgical recurrence of knee instability. 相似文献55.
Carlos de Paula Eduardo Ana Cecilia Corrêa Aranha Alyne Simões Marina Stella Bello-Silva Karen Muller Ramalho Marcella Esteves-Oliveira Patrícia Moreira de Freitas Juliana Marotti Jan Tunér 《Lasers in medical science》2014,29(4):1517-1529
Recurrent herpes labialis is a worldwide life-long oral health problem that remains unsolved. It affects approximately one third of the world population and causes frequent pain and discomfort episodes, as well as social restriction due to its compromise of esthetic features. In addition, the available antiviral drugs have not been successful in completely eliminating the virus and its recurrence. Currently, different kinds of laser treatment and different protocols have been proposed for the management of recurrent herpes labialis. Therefore, the aim of the present article was to review the literature regarding the effects of laser irradiation on recurrent herpes labialis and to identify the indications and most successful clinical protocols. The literature was searched with the aim of identifying the effects on healing time, pain relief, duration of viral shedding, viral inactivation, and interval of recurrence. According to the literature, none of the laser treatment modalities is able to completely eliminate the virus and its recurrence. However, laser phototherapy appears to strongly decrease pain and the interval of recurrences without causing any side effects. Photodynamic therapy can be helpful in reducing viral titer in the vesicle phase, and high-power lasers may be useful to drain vesicles. The main advantages of the laser treatment appear to be the absence of side effects and drug interactions, which are especially helpful for older and immunocompromised patients. Although these results indicate a potential beneficial use for lasers in the management of recurrent herpes labialis, they are based on limited published clinical trials and case reports. The literature still lacks double-blind controlled clinical trials verifying these effects and such trials should be the focus of future research. 相似文献
56.
Aquiles Jara Cecilia Chacón Magdalena Ibaceta Andres Valdivieso Arnold J Felsenfeld 《Nephrology, dialysis, transplantation》2004,19(8):1986-1992
BACKGROUND: Both dietary phosphorus restriction and the ingestion of ammonium chloride (NH(4)Cl) given to rats on a high-phosphorus diet have been shown to preserve renal function in the azotaemic rat. Parathyroidectomy also has been reported to preserve renal function and, in addition, to prevent kidney hypertrophy in the remnant kidney model. Our goals were (i) to evaluate in azotaemic rats the effect of dietary phosphorus on renal function in a shorter time frame than previously studied and (ii) to determine whether NH(4)Cl administration (a) enhances the renoprotective effect of dietary phosphorus restriction and (b) improves renal function in the absence of parathyroid hormone (PTH). METHODS: High (H; 1.2%), normal (N; 0.6%) and low (L; <0.05%) phosphorus diets (PD) were given for 30 days to 5/6 nephrectomized rats. In each dietary group, one-half of the rats were given NH(4)Cl in the drinking water. The six groups were HPD + NH(4)Cl, HPD, NPD + NH(4)Cl, NPD, LPD + NH(4)Cl and LPD. The effect of NH(4)Cl administration was also evaluated in 5/6 nephrectomized, parathyroidectomized (PTX) rats on NPD. RESULTS: In each of the three dietary phosphorus groups, creatinine and urea clearances were greater (P<0.01) in rats receiving NH(4)Cl. Neither creatinine nor urea clearance was reduced by high dietary phosphorus. Urine calcium excretion was greatest in the LPD group and was increased (P < or = 0.001) in all three groups by NH(4)Cl ingestion. An inverse correlation was present between plasma calcium and phosphorus in the parathyroid intact (r = -0.79, P<0.001) and PTX groups (r = -0.46, P = 0.02). In PTX rats, NH(4)Cl ingestion increased (P < or = 0.01) creatinine and urea clearances and both an increasing plasma calcium concentration (r = 0.67, P<0.001) and urine calcium excretion (r = 0.73, P<0.001) increased urine phosphorus excretion. CONCLUSIONS: At 30 days of renal failure (i) NH(4)Cl ingestion increased creatinine and urea clearances, irrespective of dietary phosphorus; (ii) high urine calcium excretion, induced by dietary phosphorus restriction and NH(4)Cl ingestion, did not adversely affect renal function; (iii) high dietary phosphorus did not decrease renal function; (iv) the absence of PTH did not preserve renal function or prevent NH(4)Cl from improving renal function; and (v) both an increasing plasma calcium concentration and urine calcium excretion resulted in an increase in urine phosphorus excretion in PTX rats. 相似文献
57.
Cecilia Ceribelli Ennio Alberto Adami Simona Mattia Bruno Benini 《Surgical endoscopy》2012,26(12):3612-3615
Background
Bedside diagnostic laparoscopy has an important role of diagnosing acute abdomen in critically ill patients hospitalized in the intensive care unit (ICU). Delayed diagnosis of intraabdominal pathology increases the morbidity and mortality rates for these patients, whose clinical signs often are absent due to analgesic medication and sedation.Methods
In this retrospective study performed from January 2007 to December 2009, 62 consecutive ICU patients whose blood test results showed them to be hemodynamically unstable underwent bedside diagnostic laparoscopy. The inclusion criteria specified clinically suspected acute cholecystitis, unknown sepsis, acidosis with a high level of lactate, elevated lab tests (white blood cell count, bilirubin, lactic dehydrogenase, creatine phosphokinase, gamma glutamyl transferase [??GT]), and acute anemia with suspected intraabdominal bleeding. The major contraindications to bedside diagnostic laparoscopy were coagulopathy, endocranic hypertension, and heart failure. Patients with a clear indication for an open surgical procedure were excluded from the study.Results
Of the 62 patients who underwent bedside diagnostic laparoscopy, 43 (69.3?%) had positive findings and 29 (46.7?%) had acute acalculous cholecystitis. The mean operation time was 38 min, and no procedure-related deaths occurred. The procedure was performed for postsurgery patients, especially after cardiac operations, and for trauma or septic patients. Respiratory and hemodynamic parameters were monitored before, during, and after the procedure.Conclusions
As a minimally invasive procedure, bedside diagnostic laparoscopy can be performed in the ICU for hemodynamically unstable patients. It is safe procedure with high diagnostic accuracy for acute intraabdominal conditions that avoids negative laparotomies for unstable patients. The bedside diagnostic laparoscopy procedure is not performed widely, and prospective studies are needed to better evaluate outcome and advantages for critically ill patients. 相似文献58.
59.
Raviv Y D'Ovidio F Pierre A Chaparro C Freeman M Keshavjee S Singer LG 《Clinical transplantation》2012,26(1):133-142
The main cause of late morbidity and mortality after lung transplantation is bronchiolitis obliterans syndrome (BOS). This study assesses the prevalence of gastroparesis among lung-transplant recipients and its association with BOS. The files of 139 patients who underwent nuclear gastric emptying studies before and/or three and 12 months after lung transplantation were reviewed, and the correlation of gastric emptying time (GET) at each time point with the occurrence of acute rejection or BOS (stage 0p or higher) was evaluated. Delayed gastric emptying (DGE; t(1/2) > 90 min) was documented in 50% of patients before transplantation - 74% at three months and 63% at 12 months. Median pre-transplant t(1/2) was 108 min in patients who acquired BOS and 77 min in BOS-free patients (p = 0.022). Among patients with pre-transplant DGE, 58% were BOS-free at 24 months post-operatively and 37% at 36 months; corresponding rates in patients with normal motility were 78% and 63% (p = 0.084). On multiple regression analysis adjusting for other measures of upper gastrointestinal dysfunction, GET before or three months after transplantation was significantly associated with BOS (OR 1.05 [95% CI 1.01-1.09] and OR 1.001 [1.001-1.005] per minute t(1/2)). Gastroparesis is common in lung-transplant recipients and associated with the development of BOS. 相似文献
60.
Radde R Duma C Goedert M Jucker M 《European journal of nuclear medicine and molecular imaging》2008,35(Z1):S70-S74
To study Alzheimer's disease (AD), a variety of mouse models has been generated through the overexpression of the amyloid precursor protein and/or the presenilins harboring one or several mutations found in familial AD. With aging, these mice develop several lesions similar to those of AD, including diffuse and neuritic amyloid deposits, cerebral amyloid angiopathy, dystrophic neurites and synapses, and amyloid-associated neuroinflammation. Other characteristics of AD, such as neurofibrillary tangles and nerve cell loss, are not satisfactorily reproduced in these models. Mouse models that recapitulate only specific aspects of AD pathogenesis are of great advantage when deciphering the complexity of the disease and can contribute substantially to diagnostic and therapeutic innovations. Incomplete mouse models have been key to the development of Abeta42-targeted therapies, as well as to the current understanding of the interrelationship between cerebral beta-amyloidosis and tau neurofibrillary lesions, and are currently being used to develop novel diagnostic agents for in vivo imaging. 相似文献