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1.
The participation of gonadotropins in ovarian carcinogenesis is well known and is supported by studies with inhibition of pituitary gonadotropin secretion, which results in a diminished risk of cancer. However, there are few data on localization and expression of Follicle Stimulating Hormone and Luteinising Hormone Receptors (FSHR and LHR) in ovaries of healthy postmenopausal women, and their correlation with FSH and LH concentration in blood serum is unknown. The aim of our study was to analyze gonadotropin concentration in blood serum and the expression of FSHR and LHR in ovaries of 207 postmenopausal women. Patients included in the study were divided into three groups depending on the number of years since menopause. We analyzed the concentration of FSH and LH in blood serum and the expression of FSHR and LHR in ovaries. Ovaries of postmenopausal women showed numerous morphological changes in the cortex and medulla when compared to the structure of ovaries of women at reproductive age. In all groups of patients clefts in the surface epithelium and epithelial inclusion cysts were found. The concentration of FSH and LH in the blood serum of women studied increased significantly with time from menopause. Significant differences between analyzed menopausal groups were found. The highest FSH and LH concentration in blood serum were found in women with the longest period of time from menopause. Quantitatively similar expression of FSHR and LHR was found in ovarian surface epithelial cells, in epithelial inclusion cysts and in the connective tissue cells of ovarian stroma. The intensity of the immunohistochemical reaction decreased with time from menopause and with age.  相似文献   

2.
Background:Polycystic ovary syndrome (PCOS) is the most common cause of ovarian dysfunction associated with infertility, Oligomenorrhea or amenorrhea, hirsutism, acne, and obesity. A large body of evidence unraveled, three major groups of genes play critical roles in underlying PCOS molecular mechanism. The aim of this study is to investigate critical exonic variant of FSHR, CYP11, and INSR and determine the functionality of these mutations in Iranian patients with PCOS.Methods:In this case-control study, 130 patients with PCOS who referred to the Vali-e-Asr Hospital with infertility were included. DNA extracted from three ml of peripheral blood of the participants for DNA extraction. The PCR was conducted for each gene and the PCR product was genotyped by sequencing. Results:The data showed that there were two polymorphisms in INSR genes which did not change the protein sequences; these alterations can also be considered as a single nucleotide polymorphism (SNP). Moreover, any exonic variant has not been detected in CYP11B1. Whereas, two missense mutation have been detected in FSHR gene including p.Ala307Thr and p.Asn680Ser. It has been shown that the polymorphisms of the FSHR gene affect the hormone response in the ovaries. Our data demonstrated that the FSHR mutations frequencies were higher in the patients with PCOS rather than control people significantly.Conclusion:These data showed that the polymorphisms of FSHR were significantly associated with PCOS in Iranian infertile women. Further studies with larger sample sizes are needed to be performed for explore the strength of the association.Key Words: CYP11, FSHR, Infertile, INSR, PCOS, Polymorphisms  相似文献   

3.
4.
Polycystic ovary syndrome (PCOS) is a common condition in women associated with menstrual irregularity and anovulation. While obesity worsens and weight loss or exercise improves reproduction function in PCOS, the mechanism for this is unclear. The aim of this study was to examine the effect of exercise on ovarian hormones [anti-Müllerian hormone (AMH)] and menstrual and ovulatory function in women with and without PCOS. Overweight women with (n=7) and without (n=8) PCOS of comparable age, weight and BMI undertook a 12-week intensified endurance exercise training program (1?h 3 times/week) with no structured energy restriction. Primary outcomes were AMH, ovulation (weekly urinary pregnanediol) and menstrual regularity. Secondary outcomes were insulin resistance (euglycemic hyperinsulinemic clamp) and body composition (computed tomography and dual X-ray absorptiometry). Exercise decreased BMI, total and android fat mass and improved insulin sensitivity for all women. AMH was significantly higher in women with PCOS compared to controls before (p<0.001) and after exercise (p=0.001). There was a significant interaction between AMH changes with exercise and PCOS status (p=0.007) such that women without PCOS had no change in AMH (+1.4±5.2?pmol/l, p=0.48) while women with PCOS had a decrease in AMH (-?13.2±11.7?pmol/l, p=0.025). Exercise is associated with improvements in ovarian hormones in women with abnormal ovarian function. This suggests that mechanisms associated with ovarian dysfunction can be improved by exercise in PCOS.  相似文献   

5.
In ovarian granulosa cells, follicle-stimulating hormone (FSH) regulates the proliferation and differentiation events required for follicular growth and oocyte maturation. FSH actions are mediated exclusively through the FSH receptor (FSHR). In cattle, the FSHR gene expression pattern during folliculogenesis and the implications of this receptor in reproductive disorders have been extensively studied. However, the limited availability of specific antibodies against bovine FSHR has restricted FSHR protein analysis. In the present study, we developed an anti-FSHR polyclonal serum by using a 14-kDa peptide conjugated to maltose binding protein. The antiserum obtained was characterized by western blot of protein extracts from bovine follicles, BGC-1 cells and primary cultures of granulosa cells stimulated with testosterone. Also, the blocking effect of serum on estradiol secretion and cell viability after gonadotropin stimulus was characterized in a functional in vitro assay. A 76-kDa protein, consistent with the predicted molecular size of full-length FSHR, was detected in ovarian tissue. Besides, two immunoreactive bands of 60-kDa and 30-kDa (only in cultured cells) were detected. These bands would be related to some of the isoforms of the receptor. Therefore, immunohistochemical assays allowed detecting FSHR in the cytoplasm of granulosa cells and an increase in its expression as follicles progressed from primordial to large preantral follicles. These results suggest that the anti-FSHR serum here developed has good reactivity and specificity against the native FSHR. Therefore, this antiserum may serve as a valuable tool for future studies of the biological function of FSHR in physiological conditions as well as of the molecular mechanism and functional involvement of FSHR in reproductive disorders.  相似文献   

6.
Recent studies suggest that bone marrow stem cells (BMSCs) are promising grafts to treat a variety of diseases, including reproductive dysfunction. Primary ovarian failure is characterized by amenorrhea and infertility in a normal karyotype female, with an elevated serum level of follicle-stimulating hormone (FSH) and a decrease level of estrogen caused by a mutation in FSH receptor (FSHR) gene. Currently, there is no effective treatment for this condition. The phenotype of FSHR (-/-) mouse, FORKO (follitropin receptor knockout), is a suitable model to study ovarian failure in humans. Female FORKO mice have elevated FSH, decreased estrogen levels, are sterile because of the absence of folliculogenesis, and display thin uteri and small nonfunctional ovaries. In this study, we determined the effects of BMSC transplantation on reproductive physiology in this animal model. Twenty four hours post BMSC transplantation, treated animals showed detectable estroidogeneic changes in daily vaginal smear. Significant increase in total body weight and reproductive organs was observed in treated animals. Hemotoxylin and eosin (H&E) evaluation of the ovaries demonstrated significant increase in both the maturation and the total number of the follicles in treated animals. The FSH dropped to 40-50% and estrogen increased 4-5.5 times in the serum of treated animals compared to controls. The FSHR mRNA was detected in the ovaries of treated animals. Our results show that intravenously injected BMSCs were able to reach the ovaries of FORKO mice, differentiate and express FHSR gene, make FSHR responsive to FSH, resume estrogen hormone production, and restore folliculogenesis.  相似文献   

7.
Premature ovarian failure occurs in almost 1% of women under age 40. Molecular alterations of the FSH receptor (FSHR) have recently been described. A first homozygous mutation of the FSHR was identified in Finland. More recently, we described two new mutations of the FSHR in a woman presenting a partial FSH-resistance syndrome (patient 1). We now report new molecular alterations of the FSHR in another woman (patient 2) who presented at the age of 19 with primary amenorrhea contrasting with normal pubertal development. She had high plasma FSH, and numerous ovarian follicles up to 3 mm in size were evidenced by ultrasonography. Histological and immunohistochemical examination of ovarian biopsies revealed the presence of a normal follicular development up to the antral stage and disruption at further stages. DNA sequencing showed two heterozygous mutations: Asp224Val in the extracellular domain and Leu601Val in the third extracellular loop of FSHR. Cells transfected with expression vectors encoding the wild type or the mutated Leu601Val receptors bound hormone with similar affinity, whereas binding was barely detectable with the Asp224Val mutant. Confocal microscopy showed the latter to have an impaired targeting to the cell membrane. This was confirmed by its accumulation as a mannose-rich precursor. Adenylate cyclase stimulation by FSH of the Leu601Val mutant receptor showed a 12+/-3% residual activity, whereas in patient 1 a 24+/-4% residual activity was detected for the Arg573Cys mutant receptor. These results are in keeping with the fact that estradiol and inhibin B levels were higher in patient 1 and that stimulation with recombinant FSH did not increase follicular size, estradiol, or inhibin B levels in patient 2 in contrast to what was observed for patient 1. Thus, differences in the residual activity of mutated FSHR led to differences in the clinical, biological, and histological phenotypes of the patient.  相似文献   

8.
Follicle-stimulating hormone-follicle-stimulating hormone receptor (FSH-FSHR) interaction is one of the most thoroughly studied signaling pathways primarily because of being implicated in sexual reproduction in mammals by way of maintaining gonadal function and sexual fertility. Despite material advances in understanding the role of point mutations, their mechanistic basis in FSH-FSHR signaling is still confined to mystically altered behavior of sTYS335 (sulfated tyrosine) yet lacking a substantial theory. To understand the structural basis of receptor modulation, we choose two behaviorally contradicting mutations, namely S128Y (activating) and D224Y (inactivating), found in FSH receptor responsible for ovarian hyperstimulation syndrome and ovarian dysgenesis, respectively. Using short-term molecular dynamics simulations, the atomic scale investigations reveal that the binding pattern of sTYS with FSH and movement of the thumb region of FSHR show distinct contrasting patterns in the two mutants, which supposedly could be a critical factor for differential FSHR behavior in activating and inactivating mutations.  相似文献   

9.
Regulation of FSH receptor promoter activation in the osteoclast   总被引:1,自引:0,他引:1  
We have shown recently that FSH stimulates osteoclast formation and function by a direct action on a G(i)-coupled FSH receptor (FSHR). Here, we report properties of the mouse FSH receptor promoter in the context of its activation in RAW-C3 osteoclast precursor macrophages. Basal promoter activity was low, but was significantly stimulated by receptor activator for NF-kappaB-ligand (RANK-L), a critical osteoclastogenic and pro-resorptive cytokine. In contrast, FSH dampened FSHR promoter activation, while estrogen had no effect. We surmise that the FSHR expression is regulated distinctly in the osteoclast, and differently from other cells, such as the ovarian follicular and Leydig cells.  相似文献   

10.
FSHR、LHR基因突变与多态对女性生殖的影响   总被引:3,自引:0,他引:3  
卵泡刺激素(FSH)与黄体生成素(LH)促进性腺的发育和成熟、调节人类配子的产生,在生殖方面起着关键的作用。两受体(FSHR与LHR)的突变会导致生殖能力的改变,出现一系列临床症状,引起组织学,分子水平等多方面的变化,同时FSHR的多态性与卵巢反应性、女性的月经周期等许多方面相关。本文从多方面阐述FSHR与LHR对女性生殖的影响。  相似文献   

11.
Although gonadotropins have been reported to downregulate FSH-receptor (FSHR) mRNA levels in the ovaries of female rats, the effect of the gonadotropin surge, particularly FSH, on hamster follicular FSHR mRNA levels warrants further examination. The objectives of the present study were to clone and determine the complete FSHR cDNA sequence of the hamster and to delineate the effects of endogenous and exogenous FSH on the steady-state levels of ovarian FSHR mRNA. Complete FSHR cDNA was derived from hamster ovarian total RNA by the strategy of 3'- and 5'-rapid amplification of cDNA ends. Ovaries were obtained before and after the endogenous gonadotropin surge or exogenous FSH administration, and the steady-state levels of FSHR mRNA were assessed by Northern blot hybridization. Cloned FSHR cDNA consists of a reading frame corresponding to exons 1-10 of the human FSHR gene and the 5'- and 3'-untranslated regions. The nucleic acid and amino acid sequences of the reading frame were at least 87% and 92% identical, respectively, to that of human, rat, and mouse FSHR. Furthermore, the amino acid sequence contained seven transmembrane domains characteristic of the FSHR. The steady-state levels of FSHR mRNA increased from estrus (Day 1) to reach a peak on proestrus (Day 4) noon; however, significant attenuation was noted following the gonadotropin surge, which was blocked by phenobarbital. Exogenous FSH also downregulated, both dose- and time-dependently, ovarian FSHR mRNA levels. These data indicate that the nucleic acid sequence of hamster FSHR has been identified and that FSH modulates FSHR mRNA levels in the hamster ovary.  相似文献   

12.
Changes in steroidogenic function and associated gene expression were characterized in dominant ovarian follicles (DF) of cattle where follicles were induced to become atretic by systemic administration of estradiol benzoate (EB). In experiment 1, follicular fluid (FF) steroid concentrations in the DF were measured at 12-hourly time points for 48 h in heifers treated with 1 mg EB i.m./500 kg body weight (EB; n=20) as compared with untreated controls (C; n=19). Treatment with EB promoted a transient reduction in circulating FSH, a rapid (12 h) and sustained reduction in FF estradiol, a rapid (12 h) but transient reduction in FF progesterone and a delayed (36 h) increase in FF testosterone concentrations. In experiment 2, whole follicular wall tissue was collected from DF of mature non-lactating cows allocated to a 0 h control group (0 HC: n=7), a 24h control group (24 HC; n=7) or an EB-treated group where tissue was collected 24 h after administration of 1 mg EB i.m./500 kg body weight (EB; n=8). As for experiment 1, EB promoted a transient reduction in circulating FSH, a pronounced reduction in FF estradiol and a smaller but significant reduction in FF progesterone concentrations. Semi-quantitative RT-PCR on follicular wall tissue revealed that the loss in estrogen activity at 24 h after EB was associated with two-fold reduction in aromatase mRNA, with an apparent acceleration in loss of 17alpha-hydroxylase mRNA. Expression of genes for gonadotropin receptors (LHR and FSHR) and a cell-death signalling pathway (Fas antigen and Fas ligand) were unchanged during the initial 24h of EB-induced atresia. These results suggest that EB initiates atresia in dominant ovarian follicles through a rapid suppression of follicular estradiol synthesis, an effect associated with down-regulation of the aromatase gene. A transient suppression in circulating FSH following administration of EB appears to have initiated these events, and it is suggested that subsequent processes involved in atresia follow this loss in estrogenic function.  相似文献   

13.
FSH mediates its testicular actions via a specific Sertoli cell G protein-coupled receptor. We created a novel transgenic model to investigate a mutant human FSH receptor (FSHR(+)) containing a single amino acid substitution (Asp567Gly) equivalent to activating mutations in related glycoprotein hormone receptors. To examine the ligand-independent gonadal actions of FSHR(+), the rat androgen-binding protein gene promoter was used to direct FSHR(+) transgene expression to Sertoli cells of gonadotropin-deficient hypogonadal (hpg) mice. Both normal and hpg mouse testes expressed FSHR(+) mRNA. Testis weights of transgenic FSHR(+) hpg mice were increased approximately 2-fold relative to hpg controls (P < 0.02) and contained mature Sertoli cells and postmeiotic germ cells absent in controls, revealing FSHR(+)-initiated autonomous FSH-like testicular activity. Isolated transgenic Sertoli cells had significantly higher basal ( approximately 2-fold) and FSH-stimulated ( approximately 50%) cAMP levels compared with controls, demonstrating constitutive signaling and cell-surface expression of FSHR(+), respectively. Transgenic FSHR(+) also elevated testosterone production in hpg testes, in the absence of circulating LH (or FSH), and it was not expressed functionally on steroidogenic cells, suggesting a paracrine effect mediated by Sertoli cells. The FSHR(+) response was additive with a maximal testosterone dose on hpg testicular development, demonstrating FSHR(+) activity independent of androgen-specific actions. The FSHR(+) response was male specific as ovarian expression of FSHR(+) had no effect on hpg ovary size. These findings reveal transgenic FSHR(+) stimulated a constitutive FSH-like Sertoli cell response in gonadotropin-deficient testes, and pathways that induced LH-independent testicular steroidogenesis. This novel transgenic paradigm provides a unique approach to investigate the in vivo actions of mutated activating gonadotropin receptors.  相似文献   

14.
《Reproductive biology》2022,22(1):100580
The present study aims to examine the role of kisspeptin (KP), FSH, and its receptor (FSHR), and their interrelationships in the control of basic human ovarian granulosa cells functions. We investigated: (1) the ability of granulosa cells to produce KP and FSHR, (2) the role of KP in the control of ovarian functions, and (3) the ability of KP to affect FSHR and to modify the FSH action on ovarian functions. The effects of KP alone (0, 10 and 100 ng/mL); or of KP (10 and 100 ng/mL) in combination with FSH (10 ng/mL) on cultured human granulosa cells were assessed. Viability, markers of proliferation (PCNA and cyclin B1) and apoptosis (bax and caspase 3), as well as accumulation of KP, FSHR, and steroid hormones, IGF-I, oxytocin (OT), and prostaglandin E2 (PGE2) release were analyzed by the Trypan blue exclusion test, quantitative immunocytochemistry, and ELISA. KP given at a low dose (10 ng/mL) stimulated viability, proliferation, inhibited apoptosis, promoted the release of progesterone (P4), estradiol (E2), IGF-I, OT, and PGE2, the accumulation of FSHR, but not testosterone (T) release. KP given at a high dose (100 ng/mL) had the opposite, inhibitory effect. FSH stimulated cell viability, proliferation and inhibited apoptosis, promoted P4, T, E2, IGF-I, and OT, but not PGE2 release. Furthermore, KP at a low dose promoted the stimulatory effect of FSH on viability, proliferation, P4, E2, and OT release, promoted its inhibitory action on apoptosis, but did not modify its action on T, IGF-I, and PGE2 output. KP at a high dose prevented and inverted FSH action. These results suggest an intra-ovarian production and a functional interrelationship between KP and FSH/FSHR in direct regulation of basic ovarian cell functions (viability, proliferation, apoptosis, and hormones release). The capability of KP to stimulate FSHR, the ability of FSH to promote ovarian functions, as well as the similarity of KP (10 ng/mL) and FSH action on granulosa cells’ viability, proliferation, apoptosis, steroid hormones, IGF-I, OT, and PGE2 release, suggest that FSH influence these cells could be mediated by KP. Moreover, the capability of KP (100 ng/mL) to decrease FSHR accumulation, basal and FSH-induced ovarian parameters, suggest that KP can suppress some ovarian granulosa cell functions via down-regulation of FSHR. These observations propose the existence of the FSH-KP axis up-regulating human ovarian cell functions.  相似文献   

15.
Zhang Z  Gong F  Lu GX 《Peptides》2012,34(2):343-348
The aim of the study was to evaluate the plasma level of calcitonin gene-related peptide (CGRP) in patients with polycystic ovary syndrome (PCOS) and its relationship to hormonal and metabolic parameters. We also observed the effect of CGRP on testosterone (T) and estradiol (E(2)) release in cultured human granulosa cells. PCOS subjects (n=215) and matched healthy control women (n=103) at age of 22-38 years were enrolled in this study. We analyzed plasma CGRP concentrations, relationship of plasma CGRP with insulin resistance (IR), body mass index (BMI), luteinizing hormone/follicle-stimulating hormone (LH/FSH) ratio and T. The T and E(2) release levels of cultured human granulosa cells treated by CGRP were also measured. The results showed that plasma CGRP concentrations were significantly higher in women with PCOS than those of control subjects. In women with PCOS, there was a strong positive correlation between the plasma CGRP level with HOMA-IR, AUC-insulin, AUC-glucose, the ratio of LH/FSH and plasma T concentration. Human granulosa cells expressed CGRP receptor. Exogenous CGRP caused an elevation of T and E(2) released from the human granulosa cells. These findings suggest that CGRP may participate in the pathophysiological process of PCOS.  相似文献   

16.

Background

Follicular stimulating hormone (FSH) is a glycoprotein and widely used for the treatment of infertility; FSH action is mediated by FSH receptor (FSHR), SNPs of which determine the ovarian response. Two polymorphisms of the FSHR gene were identified, which caused a change of threonine (T) to alanine (A) at position 307 and asparagine (N) to serine(S) at position 680. Both polymorphic sites give rise to three discrete variants of the FSHR: TT, TA, and AA for position 307; NN, NS, and SS for position 680.

Methodology/Principal Findings

450 Chinese women were recruited in an assisted reproductive technology program from October 2011 to March 2012. FSHR polymorphisms at the positions 307 and 680 were examined by PCR-RFLP. Serum FSH and estradiol level, FSH amount, ovarian response and pregnancy rate were recorded during treatment. The basal FSH levels were higher in AA [7.38 ± 2.07 vs 6.34 ± 1.75, 6.63 ± 1.94, P<0.05, 95% CI (6.75, 8.01)] and SS [7.51 ± 2.01 vs 6.31 ± 1.75, 6.66 ± 1.96, P<0.05, 95% CI (6.88, 8.15)] compared to other genotypes respectively; the days for ovulation induction was slightly longer in AA and SS. Women with AA and SS have higher rates of poor response compared to carriers of other genotypes (P<0.05). Furthermore, there is a nearly complete linkage between these two polymorphisms in Chinese women (D’=0.95, r2=0.84).

Conclusions/Significance

In Chinese women receiving ART, the subjects with AA and SS genotypes have higher basal FSH levels, and these genotypes are associated with an increased risk of poor response. Our data suggested that the personalized FSH therapy may be applied according to patient’s genetic background in clinical settings. The linkage suggested that the polymorphisms of Thr307Ala and Asn680Ser may be used as TAG-SNP markers for analysis of potential genotyping in ART.  相似文献   

17.
The objective of this study was to explore age-related differences in the reproductive and metabolic manifestations of polycystic ovarian syndrome (PCOS). Using a prospective cross-sectional design, we compared metabolic and reproductive findings in women attending a multidisciplinary clinic for PCOS, stratified across the following age groups: 18-25 (n = 71), 26-35 (n = 129), and 36-45 (n = 29). The study included primarily overweight and obese women, with a mean BMI of 31.1 in the entire study group. Older women had a decreased prevalence of biochemical hyperandrogenemia (p-trend: 0.0005). Of women meeting diagnostic criteria for PCOS, older women (n = 15) had larger median waist circumference and higher median diastolic blood pressure, total cholesterol, LDL cholesterol and fasting glucose compared to younger women (p-trend: 0.03, 0.01, 0.01, 0.01 and 0.06, respectively). The odds of metabolic syndrome for women ages 36-45 are increased four-fold relative to the younger groups (OR: 4.01; 95% CI: 1.04-15.4; p = 0.04). We conclude that there are significant age-related differences in both the clinical presentation and metabolic manifestations of PCOS.  相似文献   

18.
Estrogens act through binding to estrogen receptor α (ERα) and β (ERβ). Studies in knockout mice have shown that the absence of ERα leads to the polycystic ovary syndrome (PCOS) phenotype. Furthermore, the expression of ERβ gene is lower in follicles derived from women with PCOS compared with healthy women. The aim of this study was to investigate the importance of ERα and ERβ gene polymorphisms in PCOS. A cohort of 180 women with PCOS and 140 healthy controls were recruited, and the PvuII and XbaI polymorphisms of ERα, as well as, the AluI and RsaI polymorphisms of ERβ were genotyped. No difference was found in the distribution of these polymorphisms between patients and healthy controls. However, in PCOS women, carriers of TC and TT genotypes of PvuII polymorphism had lower fasting glucose to insulin ratio compared with carriers of CC genotype (p = 0.029). In addition, the presence of AA genotype of XbaI polymorphism was associated with lower levels of follicle-stimulating hormone (FSH) compared with the presence of AG and GG genotypes (p = 0.03). The association of ERα polymorphisms with insulin resistance indices and FSH levels emphasizes the importance of ERα as a genetic modifier of the PCOS phenotype.  相似文献   

19.
In an attempt to evaluate whether high basal day-3 luteinizing hormone/follicle-stimulating hormone (LH/FSH) ratio affects IVF cycle outcome in polycystic ovary syndrome (PCOS) patients undergoing ovarian stimulation with either GnRH-agonist (n = 47) or antagonist (n = 104), we studied 151 IVF cycles: 119 in patients with basal LH/FSH <2 and 32 in patients with LH/FSH ≥ 2. The PCOS with high LH/FSH ratio achieved a non-significantly higher pregnancy rate using the GnRH-agonist (50% vs 17.9%, p = 0.2; respectively), as compared to the GnRH-antagonist protocols, probably due to the ability of the long GnRH-agonist protocol to induce a prolong and sustained reduction of the high basal LH milieu and avert its detrimental effect on oocyte quality and implantation potential.  相似文献   

20.
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