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We have demonstrated a compact and cost-effective ytterbium-doped all-fiber laser operating at 976â nm. By utilizing a commercially available ytterbium-doped fiber with a length of only 18â cm, we achieved a lasing power of 10.3â W, with a slope efficiency of 25.4%. To our knowledge, our work presents the shortest gain fiber ever documented in the literature capable of delivering tens-of-watt 976-nm lasing power. The design is compatible with conventional fiber components, simplifying the monolithic assembly process. Notably, the incorporation of such a short gain fiber obviated the need for additional measures to suppress the strong 1.03-µm emission.
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Background: Anastomotic leakage is one of the most serious complications that can occur after laparoscopic-assistedsphincter-preserving surgery for middle- and low-grade rectal cancer. Objectives: To explore the cause, prevention, and treatment of anastomotic leakage after sphincter-preserving surgery for middle- and low-grade rectal cancer under laparoscopy. Methods: The clinical data from patients with mid- and low-grade rectal cancer who underwent laparoscopic-assistedanus-preserving surgery in the anorectal surgery department of our hospital have been analyzed. Patients with a definite diagnosis, indications for laparoscopic surgery, and sphincter-preserving surgery were included in the analysis, and patients with a protective loop ileostomy and laparotomy were excluded. Results: Among the 126 patients with middle- and low-grade rectal cancer undergoing sphincter-preserving surgery under laparoscopy. There were 75 male patients and 51 female patients, ranging in age from 37 to 89 years old, with an average age of 60.2 ± 6.7. The distance from the lower edge of the rectal tumor to the anal edge was ≤10 cm. 6 developed anastomotic leakage after the operation (leakage rate of 4.7%). Moreover, turbid purulent fluid was drained from the abdominal drainage tube in three patients on the third and fourth days after the operation, and the abdominal drainage tube drained serous drainage in three more patients on the fifth and sixth days, with signs of peritonitis appearing locally. All patients received continuous flushing and negative pressure drainage with a self-made double cannula and symptomatic treatment, and all were cured and discharged. Conclusion: Many factors can cause anastomotic leakage after this operation, and adequate perioperative preparation, meticulous operation during surgery, and careful postoperative management are key factors in preventing it.
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Laparoscopia , Neoplasias Retais , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anastomose Cirúrgica/efeitos adversos , Fístula Anastomótica/etiologia , Fístula Anastomótica/prevenção & controle , Fístula Anastomótica/cirurgia , Laparoscopia/efeitos adversos , Neoplasias Retais/cirurgia , Neoplasias Retais/complicações , Estudos Retrospectivos , Tratamentos com Preservação do ÓrgãoRESUMO
We theoretically explore the mechanism in a thulium Q-switched ytterbium-doped all-fiber fiber laser using a set of rate equations to model the correlations between the photons and the five energy levels of thulium involved in the Q switching mechanism. We demonstrate that by coupling with a gain-switched resonator, the Q-switched laser is stabilized up to the maximum pulsing rate that is limited by the lifetime of level 3H5. To the best of our knowledge, this is the first study that revealed that level 3H5 plays an essential role in reinitialization, achieving sequential pulses, and limiting the maximum repetition rate.
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D2 lymph node dissection is widely used in laparoscopic radical gastrectomy for gastric cancer, and its efficacy and safety are known for patients with obesity. Currently, D2+ lymph node dissection is also applied to certain patients with gastric cancer of later stages. Due to the high difficulty of D2+ surgery, it is more challenging to perform on patients with obesity. There is currently limited research on the efficacy and safety of D2+ surgery in obese patients with gastric cancer. The present study aimed to retrospectively analyze the clinical data of patients undergoing laparoscopic radical gastrectomy for gastric cancer admitted to a single gastroenterology department. Patients with a body mass index ≥25 kg/m2 were included in the study. A total of 149 patients were selected as the research subjects and divided into two groups. The observation group comprised 74 patients who underwent D2+ lymph node dissection, while the control group comprised 75 patients who underwent standard D2 lymph node dissection. The surgical performance, postoperative recovery and postoperative complications of the two groups were compared. The results showed that the rates of conversion to open surgery in the D2+ and D2 groups were 5.4% (4/74) and 2.7% (2/75), respectively, and were not significantly different. The duration of surgery in the D2+ group (282.55±23.02 min) was significantly longer than that in the D2 group (271.45±20.05 min). The mean number of lymph node dissections in the D2+ group was 28.57±7.19, which was significantly higher than that in the D2 group (25.29±6.41). No statistically significant differences in intraoperative blood loss, time to first flatus, postoperative hospitalization days, total hospitalization expenses or postoperative complications was detected between the two groups. There were no deaths in either group within the 30-day perioperative period. In addition, there was no significant difference in the 3-year overall survival rate between the two groups, while the 5-year overall survival rate of the D2+ group was significantly higher than that of the D2 group. For obese patients with gastric cancer, D2+ surgery may increase the duration of surgery and slightly increase intraoperative blood loss compared with standard D2 radical surgery, but does not increase the incidence of postoperative complications. Moreover, D2+ surgery increases the number of lymph node dissections and improves the 5-year survival rate of patients. Therefore, it may be concluded that laparoscopic D2+ lymph node dissection is safe and feasible for obese patients with gastric cancer.
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OBJECTIVE: To conduct a systematic review to compare the early efficacies of minimally invasive surgery (MIS) versus conventional approaches in TKA (total knee arthroplasty). METHODS: Randomized controlled trials (RCTs) and clinical controlled trials (CCTs) were retrieved from the databases of MEDLINE (1996.6 - 2010.12), EMBASE (1996.6 - 2010.12), PubMed (1996 - 2010.12) and Cochrane Library (Issue 2, 2012). Journal of Orthopedics (from establishment to December 2010) and Orthopedic Journal of China (from establishment to December 2010) were manually searched. Both RCTs and CCTs were included. The data were extracted by two reviewers with designed extraction form RevMan 4.2.8 software for data analysis. The criteria were as follows: (1) operative duration and reduced blood loss; (2) VAS (visual analog scale) score; (3) faster recovery of ROM (range of movement); (4) quadriceps muscle strength; (5) component positioning malalignment; (6) tibiofemoral angle; (7) rate of complications. RESULTS: A total of 18 RCTs were included. Compared with the standard TKA procedure, the MIS group had a longer operative duration (WMD (weighted mean difference) 14.16, 95%CI (confidence interval) (12.61, 15.71)); reduced blood loss (WMD 8.31, 95%CI (6.16, 10.46)); lower VAS score at Days 3-5 post-operation (WMD 4.99, 95%CI (4.19, 5.78)); better Mean Knee Society scores at Week 6 post-operation (WMD 4.99, 95%CI (4.19, 5.78)), improvement in ROM occurred more rapidly at Month 3 post-TKA (WMD 14.59, 95%CI (8.39, 20.80)). Although the differences were not statistically significant, tibiofemoral angle was more precise in the standard group and the rate of component malalignment occurred more frequently in the MIS group (WMD 0.20, 95%CI (-0.12, 0.52)) (RR 1.57, 95%CI (0.88, 2.83)). CONCLUSION: MIS leads to a faster recovery than conventional surgery with a shorter operative duration, a reduced blood loss, a lower VAS score and a faster recovery of ROM and quadriceps muscle strength. However, the rates of component malalignment and complications occur more frequently in the MIS group. Potential benefits in long-term survival rate and functional improvement require further investigations.
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Artroplastia do Joelho/métodos , Procedimentos Cirúrgicos Minimamente Invasivos , Humanos , Prótese do Joelho , Resultado do TratamentoRESUMO
OBJECTIVE: To evaluate the effectiveness of anterior versus posterior surgical treatments of thoracolumbar fractures. METHODS: Randomized controlled trials (RCTs) and clinical controlled trials (CCTs) were identified from MEDLINE (1966 - 2006.7), EMBASE (1966 - 2006.7), PubMed (1996 - 2006.7), Cochrane Library (Issue 2, 2006).We hand-searched Chinese Journal of Orthopedics (from establishment to May 2006) and Orthopaedic Journal of China (from establishment to May 2006). RCTs and CCTs were included. Data were extracted by two reviewers with designed extraction form. RevMan 4.2.8 software was used for data analysis. RESULTS: Two RCTs and four prospective clinical trials were included. The combined results showed that compare with posterior surgical management, anterior approach in the treatment of thoracolumbar fractures proved the less incidence of complications; better neurologic recovery and corrected kyphosis angle; more complete and reliable decompression of the canal. However, there was not difference between the two groups in the general status outcomes. CONCLUSIONS: To compare with posterior fixation system, anterior surgical managements in the thoracolumbar spinal trauma might be the optimal choices because the lower rates of complications and loss of corrected kyphosis angle; better neurologic recovery, also. Besides, due to the lack of Evidence-based guidelines for the treatment of thoracolumbar spinal injuries, the results which indicated above need further study.
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Fixação Interna de Fraturas/métodos , Vértebras Lombares/lesões , Fraturas da Coluna Vertebral/cirurgia , Vértebras Torácicas/lesões , Adulto , Feminino , Humanos , Masculino , Resultado do TratamentoRESUMO
AIM: To investigate the correlation between reversal effect of cepharanthine hydrochloride (CH) on multidrug resistance (MDR) in drug-resistant cell line EAC/ADR and the nuclear transcription factor-KB (NF-KB). METHODS: Cytotoxicity was determined by the tetrazolium (MTT) assay in vitro. An EAC/ADR cell homograft model was established to investigate the effect of CH on reversing MDR in vivo. The constitutive activity and activation of NF-KB by drugs were measured by Dot-Enzyme-linked Immune Sorbent Assay (Dot-ELISA). RESULTS: CH was shown to potentiate the cytotoxicity of ADR, a 13- fold reversal effect of resistance was achieved in vitro. In mice bearing EAC/ADR cell homografts, CH was found to prolong the survival time of animals bearing tumor. Increase in life span over control was 75. 37%. In addition, the constitutive activity of NF-KB and activation of NF-KB by chemotherapy were lowered by CH. CONCLUSION: The findings suggest that CH is able to reverse drug resistance and its mechanism may be related to suppressing the constitutive activity and activation of NF-KB by drugs.
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Alcaloides/farmacologia , Carcinoma de Ehrlich/metabolismo , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Alcaloides/isolamento & purificação , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Benzilisoquinolinas , Carcinoma de Ehrlich/tratamento farmacológico , Carcinoma de Ehrlich/patologia , Linhagem Celular Tumoral , Feminino , Masculino , Camundongos , NF-kappa B/metabolismo , Transplante de Neoplasias , Raízes de Plantas/química , Plantas Medicinais/química , Distribuição Aleatória , Stephania/químicaRESUMO
OBJECTIVE: To study the expression of miRNA 320a in the brain tissue of epileptic rats and analyze its effect on the expression of aquaporin 4 (AQP4). METHODS: All rats were performed with the intraperitoneal injection of lithium chloride (3 mmol/kg) and then the intraperitoneal injection of pilocarpine (30 mg/kg) 24 h later (injected twice) to prepare the epileptic model of Wistar rats. Rats in the control group were injected with the equal volume of normal saline. According to the Racine scale, rats with over stage 3 of epilepsy were chosen and the brain tissue was separated quickly and then stored at -80 °C. The immunohistochemistry was used to detect the expression of aquaporin in the brain tissue of epileptic model and the Real-time PCR was employed to determine the difference in the expression of miRNA 320a and AQP4 in the brain tissue of rats between the epileptic model group and control group. Five 5-day neonatal Wistar rats were chosen to collect the cerebral cortex and their primary astrocytes were separated and cultured. They were transfected with miRNA mimic and imitated to the endogenous miRNA 320a to up-regulate the expression of miRNA 320a. RESULTS: In the model group, the expression of AQP4 was significantly higher than the control group (P < 0.01). However, the expression of miRNA 320a in the model group was lower than control group (P < 0.05), which was negatively correlated to AQP4. In the primary astrocytes, the transfection of miRNA 320a mimic could significantly reduce the expression of AQP4, while its inhibitor could up-regulate the expression of AQP4, which indicated that miRNA 320a could reduce the expression of AQP4. CONCLUSIONS: In the primary astrocytes of rats, the miRNA 320a could inhibit the expression of AQP4 and after adding the inhibitor of miRNA 320a, the expression of AQP4 was up-regulated.
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BACKGROUND AND OBJECTIVES: Laparoscopic-assisted distal gastrectomy has been applied to the treatment of gastric cancer. However, there have been few reports on the laparoscopic-assisted total gastrectomy for advanced gastric cancer, mainly because of the difficulty of the procedure. METHODS: Here, we report a series of cases where the hand-assisted laparoscopic total gastrectomies with regional lymph node dissection were performed successfully. RESULTS: The average operative time was 245 minutes. The mean blood loss was 110 mL. The number of dissected lymph nodes per patient was beyond 15 nodes satisfying a reliable evaluation of nodal status. All resection specimens had no residual tumor at the proximal or distal resection margins. The mean oral feeding was 3.6 days. The mean postoperative length of stay was 8.7 days. CONCLUSIONS: The hand-assisted laparoscopic D2 total gastrectomy for advanced gastric cancer is both technically feasible and safe.