Estimating standing stocks of the typical conifer stands in Northeast China based on airborne lidar data.

To promote the application of lidar technology in estimating standing stocks of the typical conifer stands in Northeast China, i.e., spruce-fir forest, larch forest, Korean pine forest, Pinus sylvestris var. mongolica forest, we combined the point cloud data obtained by airborne lidar with the data of 800 ground plots and established models of standing stocks for the four conifer stands by stepwise regression and partial least square. Partial least squares method was better than stepwise regression method (R2=0.05-0.15, RRMSE=2.6%-4.2%). Among the three types of feature variables involved in modeling, height variable (selected for 26 times) is more important than others (selected for 12 times and 11 times, respectively). With respect to the accuracy of models established based on the means of the partial least square, they worked best for Korean pine forest (R2=0.79, RMSE=60.92, RRMSE=22.9%) and larch forest (R2=0.76, RMSE=28.39, RRMSE=25.8%), followed by spruce-fir forest (R2=0.81, RMSE=46.96, RRMSE=27.7%) and P. sylvestris var. mongolica forest (R2=0.50, RMSE=55.49, RRMSE=30.4%). This study provi-ded an effective way to estimate standing stocks of four typical conifer stands in Northeast China.

[Surgical treatment for bronchioloalveolar carcinoma with ipsilateral intrapulmonary metastatic nodules].

OBJECTIVE: The staging and treatment of bronchioloalveolar carcinoma (BAC) with pulmonary metastasis are still controversial. This study aimed at evaluating the current staging of BAC with ipsilateral intrapulmonary metastatic nodules and the therapeutic effectiveness of surgical resection. METHODS: The clinicopathological data of 729 completely and surgically resected patients with non-small cell lung cancer (NSCLC) from December 1999 to December 2006 were retrospectively reviewed. Prognostic factors affecting the overall survival were analyzed by the Kaplan-Meier method and compared by the log rank test. RESULTS: Among 67 NSCLC patients with ipsilateral intrapulmonary metastatic nodules, 54 had multiple nodules in the lobe with primary lesion (T4, PM1) and 13 had additional nodules in the other ipsilateral lobes (M1, PM2). This series consisted of 40 males and 27 females, with a median age of 60.0 years. Of those, 28 had the lesions containing pure or some bronchioloalveolar carcinoma component, while the other 39 had a NSCLC lesions containing non-bronchioloalveolar carcinoma components. The median overall survival time of this series was 24.0 months. Prognostic study demonstrated that bronchioloalveolar carcinoma histology and mediastinal lymph node metastasis had significant adverse impact on the overall survival. The median survival time of the patients with bronchioloalveolar carcinoma was 58.0 months versus 27.0 months in patients with other subtypes of NSCLC (P < 0.01). The median survival times were 39.0 months for the patients with N0 or N1 versus 14.0 months for patients with N2, with a significant difference between the two groups (P < 0.01). There was no significant difference in the survival time between the patients with PM1 (36 months) and those with PM2 (24 months) (P > 0.05). CONCLUSION: Surgical resection is effective for NSCLC patients with ipsilateral intra-pulmonary metastasis, especially for those with bronchioloalveolar carcinoma components. Our results suggest that the current TNM classification system may be inappropriate for the NSCLC patients with ipsilateral intrapulmonary metastatic nodules, and may need a modification.

[Surgical treatment of ipsilateral multi-focal non-small cell lung cancer].

OBJECTIVES: The staging and treatment of multi-focal non-small cell lung cancer (NSCLC) are controversial. This study evaluated the effectiveness of surgical treatment for the ipsilateral multi-focal NSCLC. METHODS: Sixty-eight patients with multi-focal NSCLC underwent complete resection from December 1999 to December 2006. This series included 44 males and 24 females, with a mean age of 60.3 years old (range from 33 to 81 years old). Fifty-four patients had multiple nodules in primary lobe (T4) and 13 patients had additional nodules in non-primary lobe (M1), and a patient was proved to have synchronous primary NSCLC lesions. Surgical treatments included lobectomy in 53 cases, bilobectomy in 4 cases, pneumonectomy in 2 cases, and lobectomy combined with wedge resection in 9 cases. RESULTS: The median overall survival time of this series was 30 months. Prognostic study demonstrated that mediastinal lymph node metastasis and bronchioloalveolar carcinoma histology had significant impact on overall survival. The median survival times were 39 months for patients with N0 and N1, and 14 months for patients with N2, respectively, and there was significant difference between the groups (P < 0.01). The difference in survival was significant between patients with bronchioloalveolar carcinoma components and other NSCLC histologic types (P < 0.01), and the median survival times were 46 months and 20 months, respectively. CONCLUSION: Surgery could provide choice for multi-focal NSCLC patients (T4 and M1), especially for patients with bronchioloalveolar carcinoma components and without mediastinal lymph node metastasis.

Experience in using three different minimally invasive approaches in cardiac operations.

BACKGROUND: In order to reach a clear understanding of minimally invasive approaches in cardiac operations, the authors review clinical experience in using three such approaches: inferior partial median sternotomy, right anterolateral minor thoracotomy, and the right parasternal approach. MATERIAL/METHODS: Sternotomy and the three different minimally invasive approaches were applied in and 2431 and 323 patients respectively. The approaches were selected according to the circumstances of the individual case. Both external and internal cardiac structures were observed during the operations. The length of the incision, the postoperative drainage, operative time, and cardiopulmonary bypass time were investigated. The postoperative complications occurring after minimally invasive approaches were observed. RESULTS: In inferior partial median sternotomy, all structures except for the ascending aorta could be exposed well. In right anterolateral minor thoracotomy, only the structures on the right side of the heart could be exposed, but the mitral valve could also be exposed well. The exposure of the right parasternal approach was similar to that of right anterolateral minor thoracotomy. There were statistically significant differences between sternotomy and the minimally invasive approaches in terms of incision length and postoperative drainage, but no difference in operative time and cardiopulmonary bypass time. The postoperative complications of MIAs included air embolism (n = 3), chest pain (n = 9), chest wall malacia (n = 1), rib fracture (n = 2), and sternum fracture (n = 2). The total incidence of complications in minimally invasive approaches was 5.3%. CONCLUSIONS: The minimally invasive approaches can have satisfactory clinical results if the approaches are correctly chosen and performed.

[Evaluation of left parasternal approach for cardiac surgery].

OBJECTIVE: To provide a systemic evaluation of left parasternal approach (LPSA) for its clinical application. METHODS: LPSA was performed in 6 randomly-chosen formalin-preserved adult cadavers and the excisions were evaluated in external light of the external appearance, extent of traumatic injury and exposure of the structures in the thoracic cavity. RESULTS: LPSA left only short and less obvious skin incisions, thus causing minimal exterior appearance impairment. With a small operative field and only a few structures injured by this approach, LPSA had acceptable traumatic lesions and when the adequate intercostal level was chosen, the lateral structures on the left of the heart could be well exposed. CONCLUSION: LPSA is less invasive and involves acceptable external appearance impairment. Though satisfactory in exposing the structures on the left of the heart, LPSA can not properly expose the structures on the right side.