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1.
深低温冷冻保存家兔性腺器官的研究   总被引:6,自引:0,他引:6  
自1992年7月开始行深低温(-196℃)冷冻保存兔性腺研究。冷冻睾丸36个,15天后解冻,完好率91.7%,其中20个行器官移植,睾丸接通血管均即时建立血循环。4只兔的冷冻睾丸自体移植后,每次采精740.6±1890.4万个。2只兔的冷冻睾丸异体移植后,每次采精63.4±37.7万个。冷冻兔卵巢14个,15天后解冻,完好率92.9%,其中8个行器官移植,卵巢接通血管均即时建立血循环,术后雌二醇水平为2.72~127.3pmol/L。冷冻睾丸及卵巢移植一段时间后病理切片证实睾丸及卵巢组织存活。  相似文献   
2.
Summary The expression of theNeuralCell AdhesionMolecule, NCAM, in mouse gonads and ducts was studied from fetal life to maturity. The methods used were immunocytochemical staining and Western blotting. The immunocytochemical studies showed that the only structures that remain NCAM-positive throughout life were the mesonephric-derived rete ovarii and rete testis. Also in the fetal gonads some somatic cell lining the groups of differentiating germ cells were stained. In the immature as well as in the mature ovary the granulosa cells and oocytes of growing and large follicles — but not of small follicles — were stained. A particularly strong staining of the cytoplasm of the oocyte, healthy as well as atretic, was seen. All cells of the testis remained negative except for weakly stained residual bodies and late spermatids. At all ages the male ducts showed only weak staining, whereas in the female Müllerian duct the epithelium became strongly positive at puberty. The stroma of the Müllerian duct was positive during a transitory period around day 16 of fetal life in both sexes. One-dimensional gel immunoblotting of total protein from gonads, rete and ducts from immature and mature mice showed that only the two largest isoforms of NCAM (NCAM-A and NCAM-B) were present. The gonads and the rete of both sexes and the adult uterus expressed only NCAM-B, whereas NCAM-A was also detected in the adult epididymis. The present findings suggest that NCAM may be involved in the normal development and formation of both the gonads and ducts. In particular, NCAM may play a part in sustaining the integrity of the rete testis, thus ensuring the pathway for spermatozoa from the testis to the epididymis. Furthermore this cell adhesion molecule may also be important for follicular growth and differentiation.  相似文献   
3.
Inhibin B, a gonadal peptide regulating follicle stimulating hormone (FSH) secretion in adults, has been found during gestation in amniotic fluid, but at birth only in term cord blood of male babies. Since no data are available on the evolution of serum inhibin B during the 1st week of life, we studied changes in inhibin B using a specific and sensitive immunoassay in male and female neonates during the 1st week of life in relation to FSH and to evaluate the possible effect of perinatal factors on inhibin B production. Inhibin B was measured by a specific monoclonal enzyme-linked immunosorbent assay. Inhibin B was detectable in cord blood of all eight longitudinally studied male newborns, correlated negatively with the ponderal index and increased significantly on day 5 (from 54.2 ± 18.5 to 100.4 ± 34.8 ng/l, P < 0.005). Cord blood inhibin B was detected in only 1 out of 13 screened female neonates. In 48 at term-born females in whom inhibin B was measured on the 5th day of life, only 20 cases had a detectable level (between 8 and 68.6 ng/l). Inhibin B concentrations in cord blood and on day 5 were independent of duration of pregnancy, type of delivery, Apgar score and FSH concentration. Conclusion A sexual difference in serum inhibin B is already present at the end of gestation and changes in inhibin B during the 1st week of life are independent of follicle stimulating hormone changes and perinatal factors in both sexes. Our data suggest that neonatal inhibin B could be used to study whether the newborn has functional testes, i.e. in babies with ambiguous genitalia and/or bilateral cryptorchidism. Received: 30 September 1999 and in revised form 23 December 1999 and 20 January 2000 /Accepted: 20 January 2000  相似文献   
4.
Short-term effects of pyrethroids on human health are better and well identified, whereas long-term risk’s estimation remains difficult, especially those affecting the reproductive function. The present study, carried out in male rats, is a contribution to explore some effects underlying permethrin (PRMT) toxicity. The aim of the present work was to investigate the effect of different subcutaneous treatments with PRMT low doses on testes and epididymides histopathology, testosterone and oxidative stress in pubescent male rats. Groups of six animals were treated with a dermal daily dose of 0.013, 0.13, or 1.3 mg/kg b.w/day of PRMT in 70% ethanol for 30, 45, and 60 days, respectively.Macroscopic studies showed an influence of PRMT on the testes, the epididymides and body weight. The pyrethroid induces a testis disturbance traduced by a deregulation of spermatogenesis and an epididymis dysfunction by the appearance of strong deformations into the microstructure of the epididymides. A hormonal disruption was evidenced by the measurement of the plasma testosterone concentrations. The findings of the present investigation mentioned a significant increase (p≤0.05) in lipoperoxidation, after 45 or 60 days, when we measured the plasma malondialdehyde (MDA) concentrations.In conclusion the study shows that subcutaneous PRMT treatment causes an arrest of spermatogenesis, and a significant disharmony in testosterone concentration and MDA levels. These effects are related to dose, length of treatment and to the lipid peroxidation, which may be one of the molecular mechanisms involved in PRMT-induced gonads and epididymides toxicity.  相似文献   
5.
6.
Angiotensin-converting enzyme (ACE) regulates blood pressure and is an important target in the management of hypertension. Hypertension is a gender biased disease. Plasma ACE activity is significantly higher in male mice (309 U/l) than female mice (237 U/l) and is reduced significantly upon gonadectomy to 224 and 209 U/l, respectively. Although, the gonads influence plasma ACE activity in both male and female mice, the effect is more pronounced in male mice. Plasma ACE is derived from the cleavage of tissue ACE and lung has the highest concentration of tissue ACE. However, lung ACE activity is not gender dimorphic but increases significantly upon gonadectomy in both male and female. ACE mRNA level in the lung is not influenced by gender or gondaectomy. Therefore, the gonads affect plasma ACE activity by influencing cleavage of tissue ACE to plasma ACE and/or decrease stability of plasma ACE in gonadectomized mice is mediated.  相似文献   
7.
自由基清除剂预防环磷酰胺致大鼠性腺损伤的实验研究   总被引:1,自引:0,他引:1  
应用自由基清除剂维生素E、维生素C和别嘌呤醇预防环磷酰胺(CTX)所致大鼠性腺损伤。结果显示,两性预防组大鼠血和性腺组织中的丙二醛(MDA)及超氧化物歧化酶(SOD)分别明显低于和高于CTX组;电镜下,预防组大鼠睾丸精子细胞线粒体增多,空泡化明显轻于CTX组;睾丸、附睾头体重量及精子数、睾丸日产精子数和大鼠产仔数,预防组均明显高于CTX组,而胚胎吸收数则明显低于CTX组。表明维生素E、维生素C和别嘌呤醇等自由基清除剂对CTX所致的性腺损伤有一定的预防作用,在一定程度上能保护大鼠精子的发生和成熟,使其生殖功能维持在一定水平。  相似文献   
8.
The spatial organization of cells during tissue differentiation is a crucial process in the morphogenesis of vertebrates. This process involves the movement, separation, and connection of cells. It is essential to elucidate the molecular mechanisms involved in these processes for the understanding of animal morphogenesis. Cell-cell adhesion molecules, called cadherins, are involved in the selective adhesion of cells. In the case of birds, the expression of these molecules in various organ systems during embryonic development has been reported in Gallus gallus domesticus. In this work, we present the immunohistochemical analysis of the differential expression of E and N-cadherin binding molecules in Columba livia embryos at various stages of gonadal morphogenesis. The expression of E and N-cadherin in embryos corresponding to the stages 41, 43 and in neonates of 2, 5, 7 and 75 post-hatching days were assessed by immunohistochemistry. Results revealed the expression of N-cadherin in the plasma membrane and the perinuclear zone of germline cells in ovaries and testes. However, the expression of E-cadherin was noticed with similar immunoreactivity pattern, in Sertoli cells and in the cells of the follicular nests. The differential expression of follicular cells and Sertoli cells positive for E-cadherin and germline cell N-cadherin positive cells were evidenced in the present work at the cell-cell interaction level. Future studies will focus on determining the expression of E and N-cadherin molecules during the migration of the primordial germ cells and the colonization of the genital ridge.  相似文献   
9.
目的 观察口服雷公藤多苷(GTW)和(或)静脉应用环磷酰胺(CTX)对儿童性腺的远期影响.方法 回顾性收集1986年1月至2005年3月于首都儿科研究所附属儿童医院住院予GTW口服和(或)CTX静脉冲击治疗的原发性肾病综合征和过敏性紫癜肾炎患儿的资料,对停药后5年以上的患儿进行随访,内容包括开始用药时年龄,用药情况(累...  相似文献   
10.
Many hormones that are classified as neuropeptides are synthesized in vertebrate gonads in addition to the brain. Receptors for these hormones are also expressed in gonadal tissue; thus there is potential for a highly localized autocrine or paracrine effect of these hormones on a variety of gonadal functions. In the present study we focused on gonadotropin-inhibitory hormone (GnIH), a neuropeptide that was first discovered in the hypothalamus of birds. We present different lines of evidence for the synthesis of GnIH and its receptor in the avian reproductive system including gonads and accessory reproductive organs by studies on two orders of birds: Passeriformes and Galliformes. Binding sites for GnIH were initially identified via in vivo and in vitro receptor fluorography, and were localized in ovarian granulosa cells along with the interstitial layer and seminiferous tubules of the testis. Furthermore, species-specific primers produced clear PCR products of GnIH and GnIH receptor (GnIH-R) in songbird and quail gonadal and other reproductive tissues, such as oviduct, epididymis and vas deferens. Sequencing of the PCR products confirmed their identities. Immunocytochemistry detected GnIH peptide in ovarian thecal and granulosa cells, testicular interstitial cells and germ cells and pseudostratified columnar epithelial cells in the epididymis. In situ hybridization of GnIH-R mRNA in testes produced a strong reaction product which was localized to the germ cells and interstitium. In the epididymis, the product was also localized in the pseudostratified columnar epithelial cells. In sum, these results indicate that the avian reproductive system has the capability to synthesize and bind GnIH in several tissues. The distribution of GnIH and its receptor suggest a potential for autocrine/paracrine regulation of gonadal steroid production and germ cell differentiation and maturation.  相似文献   
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