The combination of lecturing and Problem-based Learning(PBL)teaching method is adopted in medical genetis. It is conducive to the development of self-directed learning skills, team skills,and problem-solving skills.

In monkey submandibular gland there were two types of capillary networks, which were apparently different in calibre and architecture, i. e. the capillary networks around the acini and the capillary networks around the striated ducts. They originate from their respective precapillary arterioles stemed from intralobular terminal arterioles. Between the two types of capillary networks they are connected by both capillaries and postcapillary venules. The latter were called portal vessels. The capillary networks around the striated duct have two types of draining vessels. First, they converged to form postcapillary venules, which continued to form intralobular veins. Second, they directly continued to form the capillary networks around the intralobular ducts. The capillary networks around the intralobular ducts directly supplied blood through precapillary arteioles around the duct besides they connected respectively with the capillary networks around the acini and striated ducts through capillaries. Furthermore, a ring-shaped constriction was observed distinctly at the intralobular terminal arteriole.

Objective:To intestigate the clinical efficacy between modified Overlap anastomosis and traditional auxiliary incision anastomosis in laparoscopic total gastrectomy.Methods:The retrospective cohort study was conducted. The clinicopathological data of 115 patients with gastric cancer who were admitted to the Second Affiliated Hospital of Fujian Medical University from January 2016 to December 2018 were collected. There were 62 males and 53 females, aged from 27 to 83 years, with a median age of 62 years. Of 115 patients, 51 patients undergoing totally laparoscopic total gastrectomy with modified Overlap anastomosis using linear stapler were divided into modified Overlap group and 64 patients undergoing laparoscopic assisted total gastrectomy with traditional auxiliary incision anastomosis using circular stapler were divided into traditional assisted group. Observation indicators: (1) surgical situations; (2) postoperative situations; (3) anastomotic complications; (4) follow-up. Follow-up using outpatient examination or telephone interview was conducted to detected tumor recurrence and survival of patients up to December 2019. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was analyzed using the t test. Count data were represented as absolute numbers or percentages, and comparison between groups was analyzed using the chi-square test or Fisher exact probability. Comparison of ranked data was analyzed using the rank sum test. Results:(1) Surgical situations: the operation time, time of esophagojejunostomy, volume of intraoperative blood loss, the number of lymph node dissected, length of proximal incisional margin and length of auxiliary incision of the modified Overlap group were (234.0±11.0)minutes, (29.4±2.1)minutes, (53±14)mL, 42±13, (2.0±0.3)cm and (5.1±0.4)cm, respectively. The above indicators of the traditional assisted group were (231.0±11.0)minutes, (29.2±2.2)minutes, (50±13)mL, 40±10, (2.2±0.4)cm and (8.2±0.4)cm, respectively. There was significant difference in the length of auxiliary incision between the two groups ( t=-43.098, P<0.05), and there was no significant difference in the operation time, time of esophagojejunostomy, volume of intraoperative blood loss, the number of lymph node dissected, length of proximal incisional margin between the two groups ( t=1.168, 0.460, 0.990, 1.127, -1.926, P>0.05). (2) Postoperative situations: cases with mild, moderate, severe pain (postoperative pain degree), time to first flatus, time to initial fluid diet intake, duration of postoperative hospital stay of the modified Overlap group were 40, 9, 2, (2.9±1.0)days, (4.8±2.2)days, (11.7±2.8)days, respectively. The above indicators of the traditional assisted group were 31, 27, 6, (3.9±1.4)days, (6.5±2.5)days, (13.0±3.1)days, respectively. There were significant differences in the above indicators between the two groups ( Z=-3.217, t= -4.344, -3.888, -2.261, P<0.05). (3) Anastomotic complications: cases with anastomotic leakage, cases with anastomotic bleeding, cases with anastomotic stenosis of the modified Overlap group were 1, 1, 0, respectively. The above indicators of the traditional assisted group were all 1. There was no significant difference in the above indicators between the two groups ( P>0.05). Cases with anastomotic leakage were cured after the treatment of enteral nutritional support through nasogastric catheterization, which were confirmed by gastroenterography. Cases with anastomotic bleeding were improved by active hemostatic therapy. Cases with anastomotic stenosis were improved after the symptomatic treatment of anti-inflammatory and anti-swelling. (4) Follow-up: 109 of the 115 patients were followed up. Forty-eight of 51 patients in the modified Overlap group were followed up for 15.0-45.0 months, with a median follow-up time of 33.5 months. Sixty-one of 64 patients in the traditional assisted group were followed up for 16.0-46.0 months, with a median follow-up time of 27.0 months. There was no tumor recurrence in the modified Overlap group. One patient in the traditional assisted group had tumor recurrence with liver metastasis and survived with tumor. There was no significant difference in tumor recurrence rate between the two groups ( P>0.05). There was no patient died during the follow-up. Conclusion:Compared with traditional auxiliary incision anastomosis, patients undergoing total laparoscopic total gastrectomy with modified Overlap anastomosis have small incision, good postoperative recovery.

Objective: To investigate the effect and mechanism of RNA binding protein Lin28 on the 5-fluorouracil (5-Fu) sensitivity of HepG2 cells. Methods: HepG2 cells were transfected with plasmid pcDNA3.1-Lin28 or si-Lin28 (small interfering RNA of Lin28). qPCR and Western blotting were used to detect the expression of Lin28 in HepG2 cells after transfection. Changes of cell proliferation in transfected cells after 5-Fu treatment was detected by CCK8 assay and the 50% inhibitory concentration (IC50) was calculated. Flow cytometry was used to detect apoptotic rate after 5-Fu treatment and the expression of apoptosis-related protein was assayed by Western blotting. The mRNA expressions of drug-resistant miRNAs (let-7a and let-7b), as well as cancer stem cell markers (Oct4, Nanog and Sox2) after transfection were detected by qPCR. Results: As compared to the HepG2/Vector cells, the mRNA and protein expressions of Lin28 were significantly up-regulated in HepG2/Lin28 cells (P<0.05 or P<0.01). Over-expression of Lin28 significantly suppressed the sensitivity of HepG2 cells to 5-Fu (IC50elevated obviously, P<0.05) and significantly increased cell proliferation while decreased apoptotic rate and expression of apoptotic-related protein caspase-3 (all P<0.01). As compared to si-control group, expression of Lin28 in HepG2/si-Lin28 cells was significantly down-regulated (P<0.01). Lin28 knockdown significantly reduced cell proliferation and IC50 of 5-Fu (all P<0.01) but increased apoptotic rate and expression of apoptosis-related protein (P<0.01). Compared with HepG2/Vector group, expressions of let-7a and let-7b, as well as cancer stem cell markers (Oct4, Nanog and Sox2) were significantly increased in HepG2/Lin28 cells (all P<0.01); while these molecules were significantly decreased in HepG2/si-Lin28 cells as comparing to si-control group (all P<0.01). Conclusion: Lin28 can modulate the chemosensitivity of HepG2 cells by regulating the expression of miRNAs and the formation of cancer stem cells. Targeting Lin28 might be a promising approach to improve the chemotherapy efficacy in HCC.