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31.

Plastic pollution control has been on top of the political agenda in China. In January 2020, China announced a phased ban on the production and usage of various types of single-use plastics as a solution to environmental pollution problems. However, the outbreak of COVID-19 seems to be a new obstacle to the ban on single-use plastic products. To basically satisfied the daily necessities and contain the spread of SARS-CoV-2 under the background of the regular epidemic prevention and control in China, online ordering, contactless delivery and wearing mask have become an important and feasible way of daily life. However, the unrestrained use of disposable plastic bags, lunch boxes and masks within the nationwide quarantine leads to hundreds of millions of plastics wastes every day. The potential environmental pollution caused by the use of disposable plastic products during the pandemic should arouse social concern. The Chinese government should manage environmental protection in parallel with anti-pandemic endeavors as the situation of the pandemic evolves.

  相似文献   
32.
Numerous techniques for the internal fixation of the cervical spine have been developed in recent years. The indications for surgery must be strictly defined before the optimal type of implant can be selected on the basis of the advantages and potential risks. Wiring techniques are still commonly used for posterior stabilization. Anterior fusion can be accomplished without internal fixation in most cases. The halo vest is still widely used for the conservative management of cervical fractures and for postoperative external immobilization. Posteriorly, traditional wiring methods are still used, as well as newer techniques, such as C1-C2 screw fixation, occipitocervical plate fixation, and lateral-mass lower cervical plating. Anteriorly, meticulous Smith-Robinson surgical approach and grafting techniques are essential. Further studies are needed to define the exact indications for various new techniques, such as anterior odontoid screw fixation and anterior plating. The surgeon must choose an appropriate device on the basis of the mechanism of injury, the pathoanatomy of the lesion, and familiarity with the device, keeping in mind the goals of internal fixation-stabilization, reduction and maintenance of alignment, early rehabilitation, and perhaps enhancement of fusion and avoidance of the need to use an external halo vest.  相似文献   
33.
低温预防周围神经缺血再灌注损伤的形态学研究   总被引:1,自引:1,他引:0  
罗晓中  安洪 《重庆医学》1999,28(3):175-176
采用暂时阻断家兔髂总动脉起始处的血流的实验模型,观察用降温方法预防坐有神经的缺血再灌注损伤(缺血4小时,再灌注5小时)的形态学变化,结果显示:神经的缺血再灌注损伤在低温下较常温下明显轻微,提示降温可预防周围神经缺血再灌注损伤。  相似文献   
34.
显性遗传性运动感觉性神经病Ⅱ型一个家系分析   总被引:1,自引:0,他引:1  
目的本文报道一个在老年期发病的遗传性运动感觉性周围神经病Ⅱ型家族。方法对家族成员进行临床和电生理检查,其中1例病人进行腓肠神经活检。结果家族成员在老年期出现四肢无力和感觉减退。老年病人和无症状年轻病人的电生理检查均发现周围神经的诱发电位波幅显著下降。腓肠神经活检证实轴索性周围神经病。结论检查结果符合显性遗传性运动感觉性周围神经病Ⅱ型的诊断,电生理检查可以发现家族中的亚临床病人。  相似文献   
35.
目的:探讨白内障超乳化摘除,睫状体平坦部下班体切割及人工晶体囊袋内植入联合手术的疗效及安全性。方法:对玻璃体视网膜病普合并白内障18例(18眼)施行该联合手术。其中糖尿病性视网膜病变,玻璃体出血伴白内障10例;视网膜分枝静脉阻塞,玻璃体出血伴白内障4例;视网膜静脉周围炎,玻璃体出血伴白内障3例及特发性视网膜1例,术后随访2~13个月(平均9月)。结果:术后视力均有不同程度提高。12眼(67%)术后  相似文献   
36.
Osteoporosis is a common finding in Turner's syndrome. To test the hypothesis that calcitonin deficiency may contribute to bone mineral loss in Turner's syndrome, we studied basal and calcium-stimulated (2 mg/kg body weight in 5 min) levels of total calcitonin, extractable calcitonin and katacalcin in 15 girls with Turner's syndrome and osteoporosis. Fifteen age-matched healthy girls were studied as controls. Both basal calcitonin (total and extractable) and katacalcin values were not significantly different in patients with Turner's syndrome in comparison with those of the controls. The calcium stimulation test showed a similar "C" cell secretory reserve in both groups. The calculation of delta CT/delta iCa of total and extractable calcitonin and delta KC/delta iCa, which accounts for individual variations in serum ionized calcium increases, did not show any significant difference between girls with Turner's syndrome and controls. We conclude that calcitonin deficiency is not a causative factor of osteoporosis in girls with Turner's syndrome and that in this syndrome long-life estrogen deficiency does not impair "C" cell secretory activity.  相似文献   
37.
The contribution of the medial and lateral collateral ligaments (MCL, LCL) and muscle forces to the kinematics and stability of the capitellocondylar total elbow arthroplasty was investigated in six fresh cadaveric elbows. The three-dimensional orientation of the ulna relative to the humerus was monitored with the use of an electromagnetic tracking device in neutral, valgus, and varus stress positions with (1) the ligaments intact, (2) LCL insufficiency obtained by osteotomizing the lateral epicondyle, (3) partial MCL insufficiency obtained by sectioning either the anterior or posterior bundle of the MCL, and (4) complete MCL insufficiency. Simulated muscle forces were applied as follows: (1) no load, (2) 1 kg each to the biceps and the brachialis and 2 kg to the triceps, and (3) 2 kg to the biceps and the brachialis and 4 kg to the triceps. The laxity was defined as the difference in valgus/varus orientation of the ulna in the valgus and varus stress positions. The laxity at 40°, 75°, and 110° elbow flexion was analyzed. The greatest laxity occurred with LCL insufficiency (40.7° ± 11.6°, average at three flexion angles) followed by that with MCL insufficiency (15.7° ± 9.9°), both of which were significantly larger than laxity with the intact ligaments (5.6° ± 2.5°). The laxity with the anterior bundle sectioned (12.0° ± 8.1°) was significantly greater than with the posterior bundle sectioned (3.3° ± 3.6°); thus the contribution of anterior bundle to stability was four times that of posterior bundle. Stabilizing effect of muscle loading was small in elbows with intact ligaments, whereas it was large with LCL or MCL insufficiency. Based on these data, we can see that the integrity of both the MCL and LCL is essential to maintain stability of this total elbow, the anterior bundle is a more important stabilizer than the posterior bundle, and the collateral ligaments seem to be the primary stabilizer and the musculature seems to be the secondary stabilizer. Careful implantation technique to preserve the collateral ligaments is required to obtain postoperative stability of this arthroplasty. Otherwise, routine exposure of the MCL and repair or reinforcement of the MCL, if deficient, may need to be considered during surgery.  相似文献   
38.
Antitumor effects of bortezomib (PS-341) on primary effusion lymphomas.   总被引:16,自引:0,他引:16  
J An  Y Sun  M Fisher  M B Rettig 《Leukemia》2004,18(10):1699-1704
Primary effusion lymphomas (PELs) are a rare type of non-Hodgkin's lymphoma that are resistant to cytotoxic chemotherapy. PELs manifest constitutive activation of nuclear factor kappa B (NF-kappaB), and inhibition of NF-kappaB induces apoptosis of PELs and sensitizes to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced death. Bortezomib (PS-341), a peptidyl boronic acid inhibitor of the proteasome, is a potent agent against a wide range of hematologic malignancies and has been shown to inhibit NF-kappaB. Thus, we examined the cytotoxic effects of bortezomib alone and in combination with various drugs. Bortezomib potently inhibited NF-kappaB in PEL cells in a dose-dependent manner. In addition, bortezomib inhibited growth and induced apoptosis of PEL cell lines (IC(50) values of 3.4-5.0 nM). Results of drug interactions between bortezomib and chemotherapy (doxorubicin and Taxol) were schedule-dependent: synergistic interactions were generally observed when PEL cells were pretreated with bortezomib prior to chemotherapy, whereas additive or even antagonistic interactions occurred with chemotherapy pretreatment or simultaneous treatment with bortezomib and chemotherapy. Most schedules of bortezomib and dexamethasone were synergistic, although pretreatment with dexamethasone resulted in additive interactions. Effects of combinations of bortezomib and TRAIL were generally additive. Thus, bortezomib represents a promising potential therapy for the treatment of PEL.  相似文献   
39.
目的:探索宁夏枸杞采收、制于规律,指导宁夏枸杞采收制干SOP的制定。方法:总结归纳宁夏枸杞采收制干现状,分析采收时间和间隔期以及制干方法对宁夏枸杞品质质量和产量的相关影响。结果与结论:正确掌握采收的最佳时机和适宜的制干方法是影响宁夏枸杞品质质量和产量的关键因素,科学合理制定宁夏枸杞采收制干SOP。  相似文献   
40.
Three cases of intravenous leiomyomatosis (IVL) of the uterus, a rare benign smooth-muscle tumor, are described. A preoperative diagnosis of IVL was not made in any of the patients, all of which presented with a pelvic mass with the presumptive diagnosis of leiomyoma. Surgical exploration confirmed the presence of uterine mass and two of the three cases showed extra-uterine extension into the ovarian or uterine veins. Histological examination demonstrated a fascicular pattern of bland spindle-shaped smooth-muscle cells, which extended to veins inside the myometrium or to extrauterine veins. This was confirmed by immunohistochemical stain for desmin and factor VIII. Despite their histological benignity, these lesions have a tendency to metastasize and are closely related to the conditions called “benign metastasizing leiomyoma” and “intracaval mass and cardiac extension”. The primary treatment of IVL is hysterectomy and excision of any extrauterine tumor, when technically feasible. Anti-estrogenic therapy has been suggested as potentially useful in controlling of unresectable tumor. According to the literature, the follow-up must be long and periodic postoperative ultrasonic or magnetic nuclear resonance imaging studies may be useful in detecting growth of residual intravascular tumor.  相似文献   
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