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991.
Giulia Cavaliere 《Bioethics》2020,34(7):727-734
In a recent article in this journal, Kathryn MacKay advances a defence of ectogenesis that is grounded in this technology’s potential to end—or at least mitigate the effects of—gender-based oppression. MacKay raises important issues concerning the socialization of women as ‘mothers’, and the harms that this socialization causes. She also considers ectogenesis as an ethically preferable alternative to gestational surrogacy and uterine transplantation, one that is less harmful to women and less subject to being co-opted to further oppressive ends. In this article, I challenge some of the assumptions that underlie MacKay’s case in favour of ectogenesis by questioning whether the relationship between women’s capacity to gestate and birth children and gender-based oppression is as strong as MacKay makes it out to be. I subsequently argue that—even if MacKay’s reading of this relationship is accurate—ectogenesis is not a desirable means to end gender-based oppression. It embodies a strategy that could be used to pursue liberating projects that follow what Iris Marion Young defines as ‘the ideal of assimilation’, but that must be resisted. I then concur with MacKay’s contention that ectogenesis is better than gestational surrogacy and uterine transplantation. My argument is that many of the problematic issues that MacKay herself sees as features of these practices will not disappear with ectogenesis. Finally, I conclude that MacKay’s narrow focus on women’s biology and ectogenesis as a solution to gender-based oppression results in the overlooking of broader systemic issues that contribute to the upholding of oppressive norms.  相似文献   
992.
In acute hepatic failure auxiliary liver transplantation is an interesting alternative approach. The aim is to provide a temporary support until the failing native liver has regenerated.1-3 The APOLT-method, the orthotopic implantation of auxiliary segments- averts most of the technical problems. However this method necessitates extensive resections of both the native liver and the graft.4 In 1998, Erhard developed the heterotopic auxiliary liver transplantation (HALT) utilizing portal vein arterialization (PVA) (Figure 1). This technique showed promising initial clinical results.5-6 We developed a HALT-technique with flow-regulated PVA in the rat to examine the influence of flow-regulated PVA on graft morphology and function (Figure 2).A liver graft reduced to 30 % of its original size, was heterotopically implanted in the right renal region of the recipient after explantation of the right kidney.  The infra-hepatic caval vein of the graft was anastomosed with the infrahepatic caval vein of the recipient. The arterialization of the donor’s portal vein was carried out via the recipient’s right renal artery with the stent technique. The blood-flow regulation of the arterialized portal vein was achieved with the use of a stent with an internal diameter of 0.3 mm. The celiac trunk of the graft was end-to-side anastomosed with the recipient’s aorta and the bile duct was implanted into the duodenum. A subtotal resection of the native liver was performed to induce acute hepatic failure. 7In this manner 112 transplantations were performed. The perioperative survival rate was 90% and the 6-week survival rate was 80%. Six weeks after operation, the native liver regenerated, showing an increase in weight from 2.3±0.8 g to 9.8±1 g. At this time, the graft’s weight decreased from 3.3±0.8 g to 2.3±0.8 g.We were able to obtain promising long-term results in terms of graft morphology and function. HALT with flow-regulated PVA reliably bridges acute hepatic failure until the native liver regenerates.  相似文献   
993.
Many neurodegenerative disorders such as Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS) and others often occur as a result of progressive loss of structure or function of neurons. Recently, many groups were able to generate neural cells, either differentiated from induced pluripotent stem cells (iPSCs) or converted from somatic cells. Advances in converted neural cells have opened a new era to ease applications for modeling diseases and screening drugs. In addition, the converted neural cells also hold the promise for cell replacement therapy (Kikuchi et al., 2011; Krencik et al., 2011; Kriks et al., 2011; Nori et al., 2011; Rhee et al., 2011; Schwartz et al., 2012). Here we will mainly discuss most recent progress on using converted functional neural cells to treat neurological diseases and highlight potential clinical challenges and future perspectives.  相似文献   
994.
目的探讨阿尔茨海默病(AD)模型鼠双侧海马区移植含多因子孵育的神经祖细胞(NPCs)后记忆认知功能改善情况及NPCs移植后迁移定位和分化能力。 方法取胎龄10?d的C57BL/6J孕鼠,分离得胎鼠NPCs,NPCs体外分化及鉴定,AD模型鼠分3组:NPCs+因子组、因子组及PBS组,对照组为同月龄C57BL/6J小鼠;Morris水迷宫及新物体识别实验检测AD模型鼠移植NPCs细胞前,及移植1至6个月后记忆行为变化情况;通过免疫荧光,免疫组化和Western-blot检测海马区移植的NPCs向神经元和胆碱能神经元分化及迁移能力。组间比较采用F检验。 结果Morris水迷宫实验中,NPCs+因子组找到平台前的逃避潜伏期时间(14.12±7.45)s要明显低于注射PBS的AD模型鼠组[(39.65±4.64)?s,F = 2.578,P = 0.0094],因子组时间(15.68±5.34)s同样低于PBS组[(39.65±4.64)s,F?= 1.324,P = 0.0016],24 h撤去平台后,NPCs+因子组逃避潜伏期时间(15.12±3.52)s仍低于PBS组[(37.17±2.18)?s,F = 2.598,P = 0.0003],因子组时间(16.62±3.23)s同样低于PBS组[(37.17±2.18)s,F = 2.186,P = 0.0004)];新物体识别实验中,各实验组对新物体探究时间占总探究时间百分比结果中,NPCs+因子组(68.46±2.4)%要高于PBS组[(54.47±4.79)%,F =3.983,P = 0.018],因子组(65.20±1.03)%同样高于PBS组[(54.47±4.79)%,F = 21.63,P = 0.042];实验结果表明,通过移植细胞与因子AD模型鼠的记忆认知功能在早期均得到改善,随着时间的增长,移植NPCs组的记忆改善情况持续时间更长久;Western blot结果显示AD模型鼠海马区胆碱能神经元与正常C57BL/6J鼠相比表达减少,移植NPCs后,AD模型鼠脑内胆碱能神经元增多;免疫荧光与免疫组化结果显示,移植的NPCs在AD模型鼠脑内移植区存活,并向胆碱能神经元分化。 结论AD模型鼠双侧海马区移植的含多因子孵育的NPCs,通过分化成功能性的胆碱能神经元来改善AD鼠的记忆认知功能。  相似文献   
995.
A reliable method is reported for the long-term preservation of ovaries and spermatozoa of the silkworm (Bombyx mori). Three studies are presented. In the first, ovaries were removed from larvae at either 3rd, 4th, or 5th instar, cryopreserved, and stored in liquid nitrogen. Thawed ovaries were transplanted to surgically castrated female larvae at the same or a different developmental stage. The highest percentage of recipient females producing eggs resulted into either 3rd or 4th instar larvae (respectively, 22.1 and 8.7%). Similarly, the highest levels of other measurements of successful cryopreservation and transplanted ovary, and number of eggs laid, occurred with the same combination of donor and recipient developmental stages. Other combinations of ovary/recipient developmental stages yielded lower results. In the second experiment, semen was collected from male moths, cryopreserved, and then thawed semen was diluted with trypsin solution and artificially inseminated into females obtained from the best conditions of first experiment. A small percentage of inseminated moths laid eggs (8-10.3%) compared to that of controls (100%). In addition, the fertility of eggs from experimental moths was lower than that of control females (respectively, 40.3-88% and 97.5%). In the third experiment, eggs were surgically removed from ovarian tubules of moth following transplantation of thawed ovaries and subjected to parthenogenetic activation and artificial hatching. As expected, all resulting moths were female and, following natural mating or artificial insemination with thawed semen, yielded normal offspring at high rates.  相似文献   
996.
Autologous hematopoietic stem cell transplantation (HSCT) has recently been performed as a novel strategy to treat patients with new-onset type 1 diabetes (T1D). However, the mechanism of autologous HSCT-induced remission of diabetes remains unknown. In order to help clarify the mechanism of remission-induction following autologous HSCT in patients with T1D, mice treated with multiple low doses of streptozotocin to induce diabetes were used as both donors (n = 20) and recipients (n = 20). Compared to streptozocin-treated mice not receiving transplantation, syngeneic bone marrow transplantation (syn-BMT) from a streptozocin-treated diabetic donor, if applied during new-onset T1D (day 10 after diabetes onset), can reverse hyperglycemia without relapse (P < 0.001), maintain normal blood insulin levels (P < 0.001), and preserve islet cell mass. Compared to diabetic mice not undergoing HSCT, syn-BMT, results in restoration of Tregs in spleens (P < 0.01), increased Foxp3 mRNA expression (P < 0.01) and increased Foxp3 protein expression (P < 0.05). This diabetic-remission-inducing effect occurred in mice receiving bone marrow from either streptozocin-treated diabetic or non-diabetic normal donors. We conclude that autologous HSCT remission of diabetes is more than transient immune suppression, and is capable of prolonged remission-induction via regeneration of CD4+CD25+FoxP3+ Tregs.  相似文献   
997.
Neural transplantation is an experimental treatment for Parkinson's disease. Widespread clinical application of the grafting technique is hampered by a relatively poor survival (around 10%) of implanted embryonic dopamine neurones. Earlier animal studies have indicated that a large proportion of the grafted cells die during graft tissue preparation and within the first few days after intracerebral implantation. The present study was designed to reveal the prevalence of cell death in rat intrastriatal grafts at 90 min, 1, 3, 6 and 42 days after implantation. We examined apoptotic cell death using semi-thin and paraffin sections stained with methylene blue and an antibody against activated caspase 3, respectively. We identified abundant apoptotic cell death up to 3 days after transplantation. In addition, we studied calpain activation using an antibody specific for calpain-cleaved fodrin. We report a peak in calpain activity 90 min after grafting. Surprisingly, we did not observe any significant difference in the number of dopaminergic neurones over time. The present results imply that grafted cells may be victims of either an early necrotic or a later apoptotic cell death and that there is substantial cell death as early as 90 min after implantation.  相似文献   
998.
In the fish germ cell transplantation system, only type A spermatogonia (ASGs) and oogonia are known to be incorporated into the recipient genital ridges, where they undergo gametogenesis. Therefore, high colonization efficiency can be achieved by enriching undifferentiated germ cells out of whole testicular cells. In this study, we used magnetic‐activated cell sorting (MACS) for enriching undifferentiated germ cells of rainbow trout using a monoclonal antibody that recognizes a specific antigen located on the germ cell membrane. We screened the antibodies to be used for MACS by performing immunohistochemistry on rainbow trout gonads. Two antibodies, nos. 172 and 189, showed strong signals for ASGs and oogonia. Next, we performed MACS with antibody no. 172 using gonadal cells isolated from vasagfp rainbow trout showing GFP in undifferentiated germ cells. We found that GFP‐positive cells are highly enriched in antibody no. 172‐positive fractions. Finally, to examine the transplantability of MACS‐enriched cells, we intraperitoneally transplanted sorted or unsorted cells into recipient larvae. We observed that transplantability of sorted cells, particularly ovarian cells, were significantly higher than that of unsorted cells. Therefore, MACS with antibody no. 172 could enrich ASGs and oogonia and become a powerful tool to improve transplantation efficiency in salmonids.  相似文献   
999.
目的分析重型肝炎肝移植受体术后真菌感染情况,进一步探讨其易感因素和防治措施。方法回顾性分析我院器官移植中心2003年3月至2006年2月间89例重型肝炎肝移植患者的临床资料并进行讨论。结果89例重型肝炎肝移植患者中21例出现术后真菌感染,感染率为23.6%,较其他病种肝移植更高,其中12例为白念珠菌(57.1%),6例为光滑念珠菌(28.6%),1例为近平滑念珠菌,1例为克柔念珠菌,1例为热带念珠菌。真菌感染多发生在术后1周内,感染部位以呼吸系统为主。结论重型肝炎肝移植患者术后真菌感染以念珠菌属的早期呼吸道感染为主。术前肝性脑病与术后发生真菌感染之间存在相关关系。而一般的白念珠菌感染不会显著地影响重型肝炎肝移植患者的预后。预防性使用抗真菌药物在重型肝炎肝移植术后真菌感染的治疗中具有重要意义。  相似文献   
1000.
Irreversible destruction of bronchi and alveoli can lead to multiple incurable lung diseases. Identifying lung stem/progenitor cells with regenerative capacity and utilizing them to reconstruct functional tissue is one of the biggest hopes to reverse the damage and cure such diseases. Here we showed that a rare population of SOX9+ basal cells (BCs) located at airway epithelium rugae can regenerate adult human lung. Human SOX9+ BCs can be readily isolated by bronchoscopic brushing and indefinitely expanded in feeder-free condition. Expanded human SOX9+ BCs can give rise to alveolar and bronchiolar epithelium after being transplanted into injured mouse lung, with air-blood exchange system reconstructed and recipient’s lung function improved. Manipulation of lung microenvironment with Pirfenidone to suppress TGF-β signaling could further boost the transplantation efficiency. Moreover, we conducted the first autologous SOX9+ BCs transplantation clinical trial in two bronchiectasis patients. Lung tissue repair and pulmonary function enhancement was observed in patients 3–12 months after cell transplantation. Altogether our current work indicated that functional adult human lung structure can be reconstituted by orthotopic transplantation of tissue-specific stem/progenitor cells, which could be translated into a mature regenerative therapeutic strategy in near future.  相似文献   
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