ObjectivesTo evaluate the learning curve for percutaneous endoscopic transforaminal discectomy（PETD）at L4/5 level and L5/S1 level respectively， and to evaluate the differences of learning curve for PETD between the two levels. MethodsTwo batches of the first 51 cases who were each treated with PETD for L4/5 or for L5/S1 disc herniation respectively in the department between December 2019 and November 2020 were reviewed. The operation time， radiation exposure time， VAS score， preoperative ODI score， and the postoperative follow-up were reviewed. Each level was divided into three groups： for the earliest stage， Patients #1~17 were assigned to Group A； for the middle stage， Patients #18~34 were assigned to Group B； and for the latest stage， Patients #35~51 were assigned to Group C. ResultsAll patients were observed postoperatively for 8.4 months ［range： 6 months-12 months， M （P₂₅~P₇₅） = 8.0（7.0~9.3）months］. Significant differences were observed in the mean operation time for L4/5 level both between Group A and Group B （P=0.006） and between Group A and Group C （P=0.000）， while for the average operation time for L5/S1 level there was significant difference between Group A and Group C （P=0.000）， but not between Group A and Group B （P=0.344）. Compared with the operation time at L4/5 level， the operation time at L5/S1 was significantly longer for each stage （Group A： P=0.080， Group B： P=0.000， Group C： P=0.016， Total： P=0.000）. The average X-ray exposure period at each Group A L4/5 level was shortened successively， and there were significant differences between Group A and Group B （P=0.000）， also between Group A and Group C （P=0.000）. However， the mean radiation time of the three stages in L5/S1 level improved less rapidly than that in L4/5 level， in which significant difference was not observed between Group A and Group B （P=0.995）， but was between Group A and Group C （P=0.000）. The radiation exposure time at L5/S1 was significantly longer than L4/5 level for each stage （Group A： P=0.000， Group B： P=0.000， Group C： P=0.000， Total： P=0.000）. In the improvement of VAS score among 3 stages for L4/5 level， no significant differences were observed neither between Group A and Group B （P=0.967） nor between Group A and Group C （P=0.927）. Higher improvement in the ODI score was observed in L4/5 level both between Group A and Group B （P=0.036） and between Group A and Group C （P=0.011）. There was no significant difference in the improvement of VAS score for L5/S1 level neither between Group A and Group B （P=0.397） nor between Group A and Group C （P=0.960）； neither was there any significant difference in the improvement of ODI score both between Group A and Group B （P=0.207） and between Group A and Group C （P=0.109）. ConclusionsThe learning curve in the L4/5 level is steeper than that in the L5/S1 level. Suitable patient selection is of much importance for shortening the learning curve for PETD.

OBJECTIVE: To retrospectively analyze non-invasive prenatal screening (NIPS) data from two centers. METHODS: The NIPS results of 10 840 samples were analyzed, including 21/18/13 trisomies (T21/T18/T13), sex chromosome and other autosomal aneuploidies, and copy number variants (CNVs). The maternal age, gestational week, body mass index and concentration of free fetal DNA (cffDNA) were also analyzed. RESULTS: The average gestational age of the 10 840 pregnant women was (32.34±5.04) year old, and the average gestational week for NIPS was (17.60±3.55) week. The overall false positive rate for T21/T18/T13 was 0.11%, sensitivity was 100%, specificity was 99.89%, and positive predictive value was 81.5%. The positive predictive values for sex chromosome and other autosomal aneuploidies and CNVs were 56.67%, 11.76% and 83.33%, respectively. The incidence of T21/T18 in the elder women (35 years or elder) was 2.12 times(P<0.01) and 1.81 times (P> 0.05) that of young women. cffDNA was in proportion to gestational week (r = 0.207) and in inverse proportion to body mass index (r = -0.177). It has increased slowly before 15 weeks of gestation and thereafter at a rate of 0.5% per week after the 16th week. CONCLUSION The performance of NIPS in this study is by large close to the reported in the literature, and the results can provide a reference for further study.

ObjectiveTo study the constituents migrating to blood of Qingyan formula by serum pharmacochemistry， and investigate the binding energy between these constituents and estrogen receptor （ER）， so as to confirm the pharmacodynamic material basis of Qingyan formula in rats. MethodUltra-high performance liquid chromatography-quadrupole electrostatic field-orbital trap high resolution mass spectrometry （UPLC-Q-Orbitrap-MS） was used to determine the constituents migrating to blood of Qingyan formula in rats by comparing the fingerprint differences of 70% ethanol extract of Qingyan formula， 70% ethanol extract of each single drug in this formula， blank serum and serum after administration of 70% ethanol extract of Qingyan formula， according to the retention time， relative molecular weight and the primary and secondary ion fragments provided by MS. Mobile phase was 0.1% formic acid aqueous solution （A）-acetonitrile（B） for gradient elution （0-5 min， 2%-20%B； 5-10 min； 20%-50%B； 10-15 min， 50%-80%B； 15-25 min， 80%-95%B； 25-26 min， 95%-2%B； 26-30 min， 2%B）， the flow rate was 0.3 mL·min^-1 and the injection volume was 5 μL， electrospray ionization was used with detection range of m/z 150-2 000， positive and negative ion scanning modes. Molecular docking technology was used to characterize the binding energy of constituents migrating to blood with ERα and ERβ， and to confirm the material basis of this formula. ResultAfter oral administration of Qingyan formula， 30 components were detected in serum， of which 9 were prototype components and 21 were metabolites. Nine prototype components were identified as monotropein， asperuloside， verbascoside， β-ecdysone， allantoin， deacetyl asperuloside acid， echinacoside， betaine and caffeic acid， 21 metabolites mainly included organic acids， amino acids， cholines and so on. The binding energies of the above 9 prototype components with ERα were -6.7， -8.9， -6.0， -5.7， -5.3， -4.9， -7.3， -3.3， -6.3 kcal·mol^-1 （1 kcal≈4 184 J）， and the binding energies of them with ERβ were -6.6， -7.2， -7.7， 8.0， -7.4， -5.5， -6.9， -3.6， -6.4 kcal·mol^-1， respectively. ConclusionThese nine prototype components into blood are the active ingredients of Qingyan formula that play estrogen-like role in the body， which can provide experimental basis for the formulation of quality standards and subsequent research and development of Qingyan formula.

ObjectiveTo observe the effect of Cuscutae Semen total flavonoids combined with Tripterygium wilfordii polyglycoside tablets （TWPT） on ovarian germline stem cells of female physiological mice through neurogenic locus notch homolog （Notch） signaling pathway. MethodSixty female Kunming mice （5 weeks old） were randomly divided into normal group， Tripterygium wilfordii polyglycoside tablets low-， high-dose groups （13.65 mg·kg^-1·d^-1 and 27.3 mg·kg^-1·d^-1， 1 and 2 times clinical equivalent dose）， Cuscutae Semen total flavonoids low- and high-dose groups （150 mg·kg^-1·d^-1 and 300 mg·kg^-1·d^-1）， and combination group （13.65 mg·kg^-1·d^-1 TWPT and 150 mg·kg^-1·d^-1 Cuscutae Semen total flavonoids）， with 10 in each group. After 3 weeks of continuous administration， the uterus/brain and ovarian/brain indexes were calculated， and the pathological changes of ovarian tissue were observed under light microscope. The content of estradiol in serum was determined by enzyme linked immunosorbent assay （ELISA）. Immunofluorescence assay was performed to observe the expressions of germline stem cell markers in ovarian epithelium， including mouse vasa homologue （Mvh）， octamer-binding transcription factor 4 （Oct4）， tyrosine-protein kinase receptor （c-kit）， Nanog， Notch signaling pathway molecules， neurogenic locus notch homolog protein 1 （Notch1）， hes family BHLH transcription factor 1（Hes1）， and jagged canonical Notch ligand 1 （JAG1）. ResultCompared with the normal group， low and high doses of TWPT had no significant effect on the uterus/brain and ovary/brain indexes and the uterus and ovary morphologies of mice， while only the number of atretic follicles was increased （P<0.01）. The expressions of ovarian germline stem cell markers and Notch signaling pathway molecules had a decreasing trend in TWPT low-dose group， while the expressions of Mvh， c-kit， and Nanog were down-regulated （P<0.05， P<0.01） and the expressions of Notch1 and Hes1 were also reduced （P<0.01） in TWPT high-dose group. However， the above indexes were increased in Cuscutae Semen total flavonoids low-dose group （P<0.05， P<0.01）. Compared with the low does of TWPT group， the combination group had a decrease in the increased number of atretic follicles （P<0.01）， an improvement in the down-regulated expressions of Mvh and Nanog （P<0.01）， and an increase in the expressions of Notch1 and Hes1 （P<0.05， P<0.01）. ConclusionOvarian germline stem cells are the source target of the reproductive toxicity of TWPT. Cuscutae Semen total flavonoids participate in the regulation of the germline stem cell pathways to alleviate the reproductive toxicity caused by TWPT， and its mechanism of action may be related to the Notch signaling pathway.