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991.
OBJECTIVE: To evaluate the safety of CO2 laser cordectomy in the treatment of glottic carcinoma as a day-case procedure. STUDY DESIGN: This was a retrospective study of a cohort of 73 patients with glottic carcinoma treated by laser cordectomy as a day-case procedure using a CO2 laser, between January 2000 and June 2004. RESULTS: There were no major complications and no patients required reintubation. More than 90 per cent of the patients were discharged on the day of the procedure. There were seven unplanned admissions to hospital but none of these appeared to be the direct result of the surgery, and the patients were discharged the next day. All the patients stated they would have further surgery in this manner if required. CONCLUSION: Laser cordectomy for glottic carcinoma can be safely performed as an out-patient procedure if patients are carefully selected according to specific criteria.  相似文献   
992.
INTRODUCTION: The sentinel lymph node is defined as the first relay of the lymphatic drainage of the tumor. Isotopic detection of the sentinel lymph node and absence of its metastatic invasion should theoretically be predictive of total drainage of the tumor. The goal of this study was to evaluate sentinel lymph node detectability by lymphoscintigraphy in N0 and/or N1 squamous-cell carcinoma of oral cavity and oropharynx and to determine its negative predictive value. MATERIAL AND METHOD: Lymphoscintigraphy was used for sentinel lymph node detection. The procedure required peritumoral injection of technicium-labeled colloids to enable anatomical and cutaneous location of the sentinel lymph node. A one-way Tyco-Mallinckrodt probe was used for intraoperative detection of the sentinel lymph node. This prospective study included 21 patients with N0 or N1 squamous-cell carcinoma of the oral cavity and the oropharynx. The surgical attitude based on T and N was not modified in this prospective study without direct individual benefit for the patient. Neck dissection was achieved without difficulty. RESULTS: The sentinel lymph node was identified in 20 out of 21 subjects. The sentinel lymph node was not identified in one patient with recurrence T2N0M0 squamous-cell carcinoma of the oropharynx radiated 3 years earlier. The percentage of false-negatives was 12.5% (1 false-negative out of 8 positive patients), giving a sensibility of the detection method of 87.5% (IC (95%)=[47.35-99.68]). This false-negative patient had a T3N0M0 squamous-cell carcinoma of the oropharynx with a sentinel lymph node removed in territory III. Neck dissection revealed 1 N + R- in the sub-mandibular territory associated with 27 N-R-. The probability of not finding a metastatic node at neck dissection when the sentinel lymph node is not metastatic (negative predictive value) was 92.3% (12/13) (IC (95)=[63.97-99.81]). The specificity of the method was 100%, as was the positive predictive value, because no sentinel node was diagnosed positive wrongly on frozen sections among patients without true histological node metastasis. DISCUSSION: For routine care of patients with squamous-cell carcinoma of the oral cavity and the oropharynx detection of the sentinel lymph node is proposed primarily for patients with T1T2N0 staging. Larger tumors can modify the architecture and flow within the lymphatic ducts, and consequently even the concept of a sentinel lymph node. Systematic neck dissection is required or T3T4, even when N0. Our series of T1T2N0 tumors is too small to enable statistically significant conclusions. A low level of false-negative in a larger series would be necessary to propose this technique instead of convention neck dissection for T1T2 tumors of the oral cavity and oropharynx.  相似文献   
993.
母婴Rh血型不合胎儿和新生儿溶血病(Rh-HDFN),是胎儿或新生儿同种被动免疫溶血性贫血最常见原因之一。Rh-HDFN导致的胎儿或新生儿病情危重,可引起胎儿严重贫血、水肿、心力衰竭、死胎,或导致新生儿核黄疸及死亡等,而幸存Rh-HDFN新生儿,则可能遗留智力发育不全、运动功能障碍等神经系统后遗症。临床对于Rh-HDFN的早期诊断、及时治疗与胎儿及新生儿预后的关系紧密相关。Rh-HDFN的产前预防,越来越受到产科临床的关注。笔者拟针对Rh-HDFN临床相关问题的最新研究进展进行阐述。  相似文献   
994.
The key role of the Langerhans cell (LC) in the immune response and particularly in allergic contact dermatitis is well documented. At first, we determined in the epidermis of the forearm by a non-sensitized adult volunteer, the variations in the density of LC (number/mm2), following the application of various chemicals: nickel sulphate 5 p. 100; erythromycin base 2 p. 100, 2,4-dinitro-1-chlorobenzene (DNCB) 0.02 p. 100 in white petrolatum. Measurements were made at 6, 24 and 48 hours. In a second stage, the volunteer was sensitized to DNCB and a similar study was performed after application of DNCB 0.02 p. 100 at 6 and 24 hours. Normal skin was used as control. The epidermis was obtained by using the suction blister method: LC were identified by the enzymatic ATPase technique and by the immunocytological OKT6 technique. Surfaces were determined by means of a computerized digital tablet. Results obtained with the ATPase technique cannot be interpreted. The density of LC determined by the OKT6 is not significantly modified when the various chemicals are applied on the skin of the non-sensitized volunteer. After sensitization to DNCB, the number of LC is significantly increased after 6 hours of application of DNCB 0.02 p. 100 but not after 24 hours. Further studies are needed to confirm these preliminary observations.  相似文献   
995.
 目的:观察SonoVue超声微泡靶向递送酸性成纤维细胞生长因子(aFGF)对糖尿病心肌病(DCM)大鼠左室舒缩功能的保护作用并初步探讨其机制。方法:24只健康雄性SD大鼠通过腹腔注射链脲佐菌素建立DCM模型,再随机平均分成DCM组与aFGF治疗组。另选择正常对照组12只。aFGF治疗组经尾静脉注射SonoVue-aFGF溶液并同时给予心肌定点超声辐照。干预后4周对所有大鼠行心导管检查,测定左室收缩末压力(LVESP)、左室舒张末压力(LVEDP)和左室内压最大上升/下降速率(LV±dp/dtmax)。处死大鼠取心肌组织,免疫组织化学染色检测心肌微血管密度(MVD),改良Masson胶原染色法测定心肌胶原容积分数(CVF),TUNEL法检测心肌组织凋亡指数(AI)。结果:干预后4周,aFGF治疗组大鼠LVESP和LV±dp/dtmax与DCM组比较明显增加(P<0.01),LVEDP较DCM组明显减低(P<0.01)。aFGF治疗组MVD测值与DCM组比较明显增加(P<0.01),而CVF及AI较DCM组明显减低(P<0.01)。结论: 超声微泡靶向递送aFGF可有效改善DCM大鼠的左心室功能,有望成为治疗DCM的新方法。  相似文献   
996.
1. The effects of prolonged light exposure, gamma-aminobutyric acid (GABA), and glycine on the horizontal cell (HC) light responses were studied in the superfused flat-mounted isolated retinas of the larval tiger salamander. 2. Under prolonged dark-adapted conditions, the time-to-peak of the HC light response was approximately 2-4 s, and after the termination of prolonged (6-8 min) light exposure, the time-to-peak became approximately 0.5-1 s. 3. This prolonged light-induced change in response rise time was not observed in either photoreceptors or bipolar cells, and thus the change in HC response rise time may occur postsynaptically in the HC membrane. 4. Application of 100 microM of GABA mimicked prolonged darkness and reversibly slowed down the HC response rise time, and application of 100 microM bicuculline mimicked prolonged light exposure and reversibly sped up the HC response rise time. 5. Glycine also slowed down the HC response rise course, but its effect was not observable until the concentration was raised to 1-3 mM. Strychnine did not exert any effect on HC responses when applied alone, but it could reverse the glycine actions. 6. The actions of glycine disappeared in the presence of bicuculline, indicating that the GABA and glycine pathways were probably not independent. Application of 5-10 mM glycine produced an increase of flow of preloaded 3H-GABA from the retina. 7. These results indicate that GABA may be the primary modulator that slows down the kinetics of the postsynaptic membrane proteins in the HCs. The extracellular concentration of GABA is probably high in prolonged darkness, and it is low after prolonged light exposure. Glycine, when applied at high dose, results in an increase of GABA release that slows down the HC response time course. 8. Prolonged darkness and light exposure appear to modulate the HC response in the time domain through GABA, and this change in HC response time course is probably responsible for shaping the bipolar cell responses and making the retinal signals more transient under light-adapted conditions.  相似文献   
997.
998.
Since cases first emerged in December 2019, COVID-19 (a type of coronavirus) has rapidly become pandemic. This fast-tracked paper (published quickly) from China on COVID-19 is written by dermatologists at the epicentre of the outbreak in Wuhan. Dermatology clinic staff may be at risk because protective equipment is not routinely available, and skin lesions might possibly transmit the virus indirectly. These authors suggest preventive measures based on experience in this and previous coronavirus outbreaks. Online consultation for non-urgent patients reduces the numbers of patients attending clinics. Nurse-led triage, to identify patients with possible COVID-19, at the entrances of hospital and skin clinics directs patients with a cough or fever to a specific COVID-19 area and a dermatologist is consulted if the fever might be related to skin disease. Clinic staff wear N95 masks and observe hand hygiene during consultations. Patients are admitted to a ward only if routine blood tests and chest CT scans exclude COVID-19. Triage will not detect patients who are showing no symptoms but who are developing the disease, so the hospital should provide an on-call expert team to discuss inpatients suspected or diagnosed with COVID-19 and refer them to radiology, respiratory or intensive care colleagues as required. Confirmed cases are managed following local policies. Skin disorders in COVID-19 inpatients can usually be managed remotely using photographs, email and teleconferencing. If necessary a multidisciplinary team (a team of medical staff from different specialties) can meet in the clean area of the isolation ward. If the dermatologist must see the patient, all records should be provided in advance to minimise exposure time. With these precautions, as of 20th February 2020 no infected patients were detected in the Wuhan Dermatology Department. This is a summary of the study: Emergency management for preventing and controlling nosocomial infection of 2019 novel coronavirus: implications for the dermatology department  相似文献   
999.
1000.
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