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991.
In normal rats callosal projections in striate cortex connect retinotopically corresponding, nonmirror-symmetric cortical loci, whereas in rats bilaterally enucleated at birth, callosal fibers connect topographically mismatched, mirror-symmetric loci. Moreover, retina input specifies the topography of callosal projections by postnatal day (P)6. To investigate whether retinal input guides development of callosal maps by promoting either the corrective pruning of exuberant axon branches or the specific ingrowth and elaboration of axon branches at topographically correct places, we studied the topography of emerging callosal connections at and immediately after P6. After restricted intracortical injections of anterogradely and retrogradely transported tracers we observed that the normal, nonmirror-symmetric callosal map, as well as the anomalous, mirror-symmetric map observed in neonatally enucleated animals, are present by P6-7, just as collateral branches of simple architecture emerge from their parental axons and grow into superficial cortical layers. Our results therefore do not support the idea that retinal input guides callosal map formation by primarily promoting the large-scale elimination of long, nontopographic branches and arbors. Instead, they suggest that retinal input specifies the sites on the parental axons from which interstitial branches will grow to invade middle and upper cortical layers, thereby ensuring that the location of invading interstitial branches is accurately related to the topographical location of the soma that gives rise to the parental axon. Moreover, our results from enucleated rats suggest that the cues that determine the mirror-symmetric callosal map exert only a weak control on the topography of fiber ingrowth.  相似文献   
992.

Background

In selected patients with rectal cancer, laparoscopic surgery is as safe as open surgery, with similar resection margins and completeness of resection. In addition, recovery is faster after laparoscopic surgery. We analyzed long-term outcomes in a group of patients with locally advanced rectal cancer (LARC) treated with preoperative therapy followed by laparoscopic surgery and intraoperative electron-beam radiotherapy (IOERT).

Methods and materials

From June 2005 to December 2010, 125 LARC patients were treated with 2 induction courses of FOLFOX-4 (oxaliplatin 85 mg/m2/d1, intravenous leucovorin at 200 mg/m2/d1–2, and an intravenous bolus of 5-fluorouracil 400 mg/m2/d1–2) and preoperative chemoradiation (4,500–5,040 cGy) followed by total mesorectal excision (laparoscopic, 35 %; open surgery, 65 %) and a presacral boost with IOERT.

Results

Patients in the laparoscopic surgery group lost less blood (median 200 vs 350 mL, p < 0.01) and had a shorter hospital stay (7 vs 11 days; p = 0.02) than those in the open surgery group. Laparoscopic procedures were shorter than open surgery procedures (270 vs 302 min; p = 0.67). Postoperative morbidity (32 vs 44 %; p = 0.65), RTOG grade ≥3 acute toxicity (25 vs 25 %; p = 0.97), and RTOG grade ≥3 chronic toxicity (7 vs 9 %; p = 0.48) were similar in the laparoscopy and open surgery groups. The median follow-up time for the entire cohort of patients was 59.5 months (range 7.8–90); no significant differences were observed between the groups in locoregional control (HR 0.91, p = 0.89), disease-free survival (HR 0.80, p = 0.65), and overall survival (HR 0.67, p = 0.52).

Conclusions

Postchemoradiation laparoscopically assisted IOERT is feasible, with an acceptable risk of postoperative complications, shorter hospital stay, and similar long-term outcomes when compared to the open surgery approach.  相似文献   
993.
994.
Abstract

Introduction: Along with increased life expectancy, the proportion of elderly patients with choledocholithiasis will increase and with this, the need for endoscopic cholangiopancreatography (ERCP). Current recommendations suggest laparoscopic cholecystectomy in all patients with choledocholithiasis to prevent biliary events. However, adherence to these recommendations is low, especially in older patients.

Methods: Retrospective study that included non-cholecystectomized patients aged >?=75 years who underwent ERCP for choledocholithiasis from 2013–2016 (n?=?131). A new biliary event was defined as the need for a new ERCP, cholecystitis, cholangitis or gallstone pancreatitis.

Aim: The aim of this study was to compare the outcomes of new biliary events and mortality in cholecystectomized vs non-cholecystectomized patients after ERCP.

Results: Cholecystectomy was performed in 22% of the patients (92% laparoscopic). The post-cholecystectomy complication rate was 13% and the mortality rate was 7%. During the follow-up period (669?±?487 days) a new biliary event occurred in 20% of patients - 10% new ERCP, 9% cholecystitis, 9% cholangitis and 2% pancreatitis. Cholecystectomized patients had fewer events (7% vs 24%, p?=?.048) and longer time to event (p?=?.016). There was no statistically significant difference in all-cause mortality (14% vs 27%, p?=?.13), mortality related to lithiasis (0% vs 9%, p?=?.11) or time to mortality from all causes (p?=?.07) and related to biliary events (p?=?.07).

Conclusions: In this group of elderly patients, cholecystectomy after ERCP prevented the occurrence of new biliary events but resulted in a non-statistically significant difference in mortality.  相似文献   
995.
996.
997.
OBJECTIVES: To provide an introduction to the legal concepts that are involved in negligence suits involving oncology nurses. DATA SOURCES: Medline, Lexis, Westlaw, legal literature and texts. CONCLUSIONS: To avoid liability and guard against negligence or malpractice suits, the oncology nurse must be aware of the legal responsibilities of each aspect of the nursing role. IMPLICATIONS FOR NURSING PRACTICE: Protecting yourself against medical malpractice begins by understanding terms and concepts that are essential in instituting legal action against the nurse and incorporating the appropriate risk reduction practices into daily practice.  相似文献   
998.
Ultrasonography is a powerful nonionizing imaging modality that has generally been underused by American Urologists in the past. Innovative investigators and clinicians, however, are realizing the great potential of ultrasonography and are applying it increasingly not only in the clinic but in the operating room. In this commentary we outline some of the current and future uses of intraoperative ultrasonography in urologic oncology.  相似文献   
999.

Background.

The need for preoperative chemoradiation or short-course radiation in all T3 rectal tumors is a controversial issue. A multicenter phase II trial was undertaken to evaluate the efficacy and safety of neoadjuvant capecitabine and oxaliplatin combined with bevacizumab in patients with intermediate-risk rectal adenocarcinoma.

Methods.

We recruited 46 patients with T3 rectal adenocarcinoma selected by magnetic resonance imaging (MRI) who were candidates for (R0) resection located in the middle third with clear mesorectal fascia and who were selected by pelvic MRI. Patients received four cycles of neoadjuvant capecitabine and oxaliplatin combined with bevacizumab (final cycle without bevacizumab) before total mesorectal excision (TME). In case of progression, preoperative chemoradiation was planned. The primary endpoint was overall response rate (ORR).

Results.

On an intent-to-treat analysis, the ORR was 78% (n = 36; 95% confidence interval [CI]: 63%–89%) and no progression was detected. Pathologic complete response was observed in nine patients (20%; 95% CI: 9–33), and T downstaging was observed in 48%. Forty-four patients proceeded to TME, and all had R0 resection. During preoperative therapy, two deaths occurred as a result of pulmonary embolism and diarrhea, respectively, and one patient died after surgery as a result of peritonitis secondary to an anastomotic leak (AL). A 13% rate of AL was higher than expected. The 24-month disease-free survival rate was 75% (95% CI: 60%–85%), and the 2-year local relapse rate was 2% (95% CI: 0%–11%).

Conclusion.

In this selected population, initial chemotherapy results in promising activity, but the observed toxicity does not support further investigation of this specific regimen. Nevertheless, these early results warrant further testing of this strategy in an enriched population and in randomized trials.  相似文献   
1000.

Objective

The purpose of this preliminary study was to determine feasibility of a clinical trial to measure the effects of manual therapy on sternocleidomastoid active trigger points (TrPs) in patients with cervicogenic headache (CeH).

Methods

Twenty patients, 7 males and 13 females (mean ± SD age, 39 ± 13 years), with a clinical diagnosis of CeH and active TrPs in the sternocleidomastoid muscle were randomly divided into 2 groups. One group received TrP therapy (manual pressure applied to taut bands and passive stretching), and the other group received simulated TrP therapy (after TrP localization no additional pressure was added, and inclusion of longitudinal stroking but no additional stretching). The primary outcome was headache intensity (numeric pain scale) based on the headaches experienced in the preceding week. Secondary outcomes included neck pain intensity, cervical range of motion (CROM), pressure pain thresholds (PPT) over the upper cervical spine joints and deep cervical flexors motor performance. Outcomes were captured at baseline and 1 week after the treatment.

Results

Patients receiving TrP therapy showed greater reduction in headache and neck pain intensity than those receiving the simulation (P < .001). Patients receiving the TrP therapy experienced greater improvements in motor performance of the deep cervical flexors, active CROM, and PPT (all, P < .001) than those receiving the simulation. Between-groups effect sizes were large (all, standardized mean difference, > 0.84).

Conclusion

This study provides preliminary evidence that a trial of this nature is feasible. The preliminary findings show that manual therapy targeted to active TrPs in the sternocleidomastoid muscle may be effective for reducing headache and neck pain intensity and increasing motor performance of the deep cervical flexors, PPT, and active CROM in individuals with CeH showing active TrPs in this muscle. Studies including greater sample sizes and examining long-term effects are needed.  相似文献   
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