Two successive severe cold waves invaded eastern China from the end of 2020 to early 2021,leading to an extensive,severe,and persistent drop in temperature.The paper investigates the features and formation mechanisms ...Two successive severe cold waves invaded eastern China from the end of 2020 to early 2021,leading to an extensive,severe,and persistent drop in temperature.The paper investigates the features and formation mechanisms of the two cold waves.The main results are as follows:(1)An anticlockwise turning of the transverse trough was observed in both cold waves.However,a broad ridge was maintained over the Ural area from mid-December 2020 till mid-January 2021.No breakdown or discontinuous westward shift of the blocking high was observed,which is different from typical cold waves in eastern Asia.(2)The maintenance and strengthening of northerly winds in front of the Ural high led to an increase in baroclinicity in-situ.In the downstream region,the gradient of the geopotential height contour in the south of the transverse trough rapidly increased and the advection of cold temperature consistently enhanced and advanced southwards.This in turn caused the intensification and southward expansion of the Siberian high.(3)Energy propagation of the quasi-stationary wave was a reason for the development and persistence of the Ural blocking.Prior to the occurrence of the two cold waves,the energy of the low-frequency stationary wave originating from near 0°E(or even to the west)propagated eastwards,which helped the Ural ridge intensify and maintain.Meanwhile,it also contributed to the development of the trough downstream of the ridge and resulted in the anticlockwise turning of the transverse trough,providing a favorable condition for the southward outbreak of cold air.展开更多
Bone metastases are rare in primary hepatocellular carcinoma （HCC）. Spinal cord compression （SCC） due to bone metastases occur commonly in patients with lung and breast carcinomas, and metastatic HCC is an unusual...Bone metastases are rare in primary hepatocellular carcinoma （HCC）. Spinal cord compression （SCC） due to bone metastases occur commonly in patients with lung and breast carcinomas, and metastatic HCC is an unusual cause of SCC. Spinal cord compression is an oncologic emergency and treatment delays can lead to irreversible consequences. Thus, the awareness that SCC could be a potential complication of bone metastases due to HCC is of significance in initiation of early treatment that can improve the quality of life and survival of the patients, if diagnosed earlier. This paper describes four cases of primary HCC with varied manifestations of SCC due to bone metastases. The first patient presented primarily with the symptoms of bone pains corresponding to the bone metastases sites rather than symptoms of associated hepatic pathology and eventually developed SCC. The second patient, diagnosed as having HCC, developed extradural SCC leading to paraplegia during the course of illness, for which he underwent emergency laminectomy with posterior fixation. The third patient developed SCC soon after the primary diagnosis and had to undergo emergency laminectomy. Post laminectomy he had good neurological recovery. The Fourth patient presented primarily with radicular pains rather than frank paraplegia as the first manifestation of SCC.展开更多
Objective To explore the feasibility and clinical results of circumferential decompression and three column reconstruction through single-stage posterior transpedicular approach for spinal tumor treatment. Methods Tot...Objective To explore the feasibility and clinical results of circumferential decompression and three column reconstruction through single-stage posterior transpedicular approach for spinal tumor treatment. Methods Totally, 24 patients with spinal tumor underwent tumor resection and spinal reconstruc tion through single-stage posterior transpedicular approach. Preoperatively, according to the Frankel classification, 12 patients were grade E, 9 grade D, and 3 grade C. Anterior column was reconstructed with non-expandable titanium cages. Posterior segmental instrumentation was used to maintain the stability of spine in all cases. Anterior and posterolateral fusion was performed with autograft and allogenic bone. The following data were followed up in these patients: deformity angle, local recurrence, neurological function, and spinal bony fusion. Results The average operating time and blood loss was 5.6 hours and 3 400 ml respectively. No intraoperative and postoperative complications were observed in this group. Postoperatively, 21 patients were Frankel grade E, 2 grade D, and 1 grade C. Four patients reported significant functional restoration and twenty patients reported complete resolution of pain. At follow-up (range, 6-42 months), implant failure or recurrent neurological symptoms was not found. Conclusions The tumor resection and spinal reconstruction through single-stage posterior transpedicular approach is a safe and effective technique for the treatment of spinal tumor. It can fully decompress the neurological structures, correct the kyphosis, and achieve early weight-bearing. This technique can improve life quality for the patients with spinal tumor.展开更多
Objective：To investigate a novel surgical method for multilevel cervical spondylotic myelopathy （CSM）. Methods： Totally 21 patients with multilevel CSM undergoing a novel surgical procedure from April 2001 to Janu...Objective：To investigate a novel surgical method for multilevel cervical spondylotic myelopathy （CSM）. Methods： Totally 21 patients with multilevel CSM undergoing a novel surgical procedure from April 2001 to January 2004 were analyzed retrospectively. All patients experienced anterior cervical decompression surgery in subsection, autograft fusion and internal fixation. Preoperative, immediate postoperative and follow-up image data, X-rays and semi-quantitative Japanese orthopaedics association （JOA） scores were used to evaluate the restoration of lordosis （Cobb＇s angle）, intervertebral heights, the stability of the cervical spine and the improvement of neurological impairment. Results： Preoperative symptoms were markedly alleviated or disappeared in most of the patients. According to the JOA scores, the ratio of improvement in neurological function was 72. 2%, including excellent in 9 cases （42.9%）, good in 7 cases （33.3%）, fair in 3 cases （14.3%） and poor in 2 cases （9.5%）. Immediate postoperative X-rays showed obvious improvements in lordosis and in the intervertebral height of the cervical spine （P〈0. 01）. There is no evidence of instrument failure during the mean follow-up period of 14. 2 months （9-24 months, P〉0. 01）. Conclusion：Anterior cervical decompression in subsection, autograft fusion and internal fixation is a rational effective method for the surgical treatment of multilevel CSM.展开更多
基金funded by a National Key Research and De-velopment Program Project[grant number 2018YFC1505601]National Natural Science Foundation of China[grant number 41975072]。
文摘Two successive severe cold waves invaded eastern China from the end of 2020 to early 2021,leading to an extensive,severe,and persistent drop in temperature.The paper investigates the features and formation mechanisms of the two cold waves.The main results are as follows:(1)An anticlockwise turning of the transverse trough was observed in both cold waves.However,a broad ridge was maintained over the Ural area from mid-December 2020 till mid-January 2021.No breakdown or discontinuous westward shift of the blocking high was observed,which is different from typical cold waves in eastern Asia.(2)The maintenance and strengthening of northerly winds in front of the Ural high led to an increase in baroclinicity in-situ.In the downstream region,the gradient of the geopotential height contour in the south of the transverse trough rapidly increased and the advection of cold temperature consistently enhanced and advanced southwards.This in turn caused the intensification and southward expansion of the Siberian high.(3)Energy propagation of the quasi-stationary wave was a reason for the development and persistence of the Ural blocking.Prior to the occurrence of the two cold waves,the energy of the low-frequency stationary wave originating from near 0°E(or even to the west)propagated eastwards,which helped the Ural ridge intensify and maintain.Meanwhile,it also contributed to the development of the trough downstream of the ridge and resulted in the anticlockwise turning of the transverse trough,providing a favorable condition for the southward outbreak of cold air.
文摘Bone metastases are rare in primary hepatocellular carcinoma （HCC）. Spinal cord compression （SCC） due to bone metastases occur commonly in patients with lung and breast carcinomas, and metastatic HCC is an unusual cause of SCC. Spinal cord compression is an oncologic emergency and treatment delays can lead to irreversible consequences. Thus, the awareness that SCC could be a potential complication of bone metastases due to HCC is of significance in initiation of early treatment that can improve the quality of life and survival of the patients, if diagnosed earlier. This paper describes four cases of primary HCC with varied manifestations of SCC due to bone metastases. The first patient presented primarily with the symptoms of bone pains corresponding to the bone metastases sites rather than symptoms of associated hepatic pathology and eventually developed SCC. The second patient, diagnosed as having HCC, developed extradural SCC leading to paraplegia during the course of illness, for which he underwent emergency laminectomy with posterior fixation. The third patient developed SCC soon after the primary diagnosis and had to undergo emergency laminectomy. Post laminectomy he had good neurological recovery. The Fourth patient presented primarily with radicular pains rather than frank paraplegia as the first manifestation of SCC.
文摘Objective To explore the feasibility and clinical results of circumferential decompression and three column reconstruction through single-stage posterior transpedicular approach for spinal tumor treatment. Methods Totally, 24 patients with spinal tumor underwent tumor resection and spinal reconstruc tion through single-stage posterior transpedicular approach. Preoperatively, according to the Frankel classification, 12 patients were grade E, 9 grade D, and 3 grade C. Anterior column was reconstructed with non-expandable titanium cages. Posterior segmental instrumentation was used to maintain the stability of spine in all cases. Anterior and posterolateral fusion was performed with autograft and allogenic bone. The following data were followed up in these patients: deformity angle, local recurrence, neurological function, and spinal bony fusion. Results The average operating time and blood loss was 5.6 hours and 3 400 ml respectively. No intraoperative and postoperative complications were observed in this group. Postoperatively, 21 patients were Frankel grade E, 2 grade D, and 1 grade C. Four patients reported significant functional restoration and twenty patients reported complete resolution of pain. At follow-up (range, 6-42 months), implant failure or recurrent neurological symptoms was not found. Conclusions The tumor resection and spinal reconstruction through single-stage posterior transpedicular approach is a safe and effective technique for the treatment of spinal tumor. It can fully decompress the neurological structures, correct the kyphosis, and achieve early weight-bearing. This technique can improve life quality for the patients with spinal tumor.
文摘Objective：To investigate a novel surgical method for multilevel cervical spondylotic myelopathy （CSM）. Methods： Totally 21 patients with multilevel CSM undergoing a novel surgical procedure from April 2001 to January 2004 were analyzed retrospectively. All patients experienced anterior cervical decompression surgery in subsection, autograft fusion and internal fixation. Preoperative, immediate postoperative and follow-up image data, X-rays and semi-quantitative Japanese orthopaedics association （JOA） scores were used to evaluate the restoration of lordosis （Cobb＇s angle）, intervertebral heights, the stability of the cervical spine and the improvement of neurological impairment. Results： Preoperative symptoms were markedly alleviated or disappeared in most of the patients. According to the JOA scores, the ratio of improvement in neurological function was 72. 2%, including excellent in 9 cases （42.9%）, good in 7 cases （33.3%）, fair in 3 cases （14.3%） and poor in 2 cases （9.5%）. Immediate postoperative X-rays showed obvious improvements in lordosis and in the intervertebral height of the cervical spine （P〈0. 01）. There is no evidence of instrument failure during the mean follow-up period of 14. 2 months （9-24 months, P〉0. 01）. Conclusion：Anterior cervical decompression in subsection, autograft fusion and internal fixation is a rational effective method for the surgical treatment of multilevel CSM.
