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1.
调节性CD4+T细胞在大鼠自发肝移植耐受中的作用   总被引:2,自引:2,他引:0  
目的 探讨在肝移植的自发耐受模型中,调节性CD4^+T细胞的免疫抑制作用机制。方法 利用近交系大鼠从Lewis(LEW)到Wistar Furth(WF)的肝移植组合,对移植后不同时期的宿主注射抗CD4的单克隆抗体(Anti-CD4mAb),然后抽血检测丙氨酸氨基转氨酶(ALT)的动态变化;并结合细胞毒性T淋巴细胞(CTL)试验了解宿主脾细胞中T细胞亚群的动态改变。结果 对肝移植自然生存的宿主注射Afiti—CD4mAb后,术后第21天、42天均能够诱导出肝损害(排斥反应),但第56天、100天以上的则未能诱导出来,且该损害能被抗CD8单克隆抗体阻断。另外CTL试验显示宿主的脾细胞中,初始型CTL前体细胞在移植56d后未能检测出来。结论 在自发性肝耐受模型中。宿主术后早期存在由CD4^+T细胞介导的下调原始效应性T细胞的作用机制。  相似文献   
2.
A rat model of monitoring liver allograft rejection   总被引:5,自引:0,他引:5  
Rat models are often used to study liver allograft rejection. We have established a model for rat liver allograft rejection, monitored by fine needle aspiration biopsy (FNAB), in the strain combination PVG-to-BN with a mean survival time of 37 ± 20 days. In this model, we observed acute rejection with an intense peak of lymphoid blasts and lymphocyte-dominated inflammation in the FNAB [9.1 ± 3.0 corrected increment units (CIU)], and an eventual increase in macrophages (up to 4.2 ± 4.4 CIU), together with fibrosis and parenchymal necrosis in the graft. Markers of immune activation, such as an increase in IL-2-receptor (from 1 % ± 2 % to 21 % ± 13 %) and class II (from 20 % ± 9 % to 43 % ± 13 %) expressing lymphoid cells and induction of ICAM-1 in the graft, were consistent with the overall cellular response. The FNAB correlated well with parallel graft histology. In this rat model, the atraumatic monitoring makes a close follow-up possible without having to sacrifice the experimental animals. This saves work, animals, and costs in the study of liver rejection. Received: 2 July 1996 Accepted: 28 October 1996  相似文献   
3.
试用中华眼镜蛇蛇毒消耗补体,观察其对豚鼠到SD大鼠异种心脏移植超急性排斥反应的影响。一次性给予小剂量CCV腹腔注射后可明显降低大鼠血清补体溶血活性,4-24小时后渐降至给药前1/2以下水平。CCV可明显延长异种移植心脏4 存活时间达2.5-36小时,对照组仅为25分钟;CCV与脾切除,前列腺素E1联用可进一步延长移植心的存活时间,最长1例达40小时。  相似文献   
4.
This report of the North American Pediatric Transplant Cooperative Study summarizes data contributed by 57 participating centers on 754 children with 761 transplants from 1 January 1989 to 16 February 1989. Data collection was initiated in October 1987 and follow-up of all patients is ongoing. Transplant frequency increased with age; 24% of the patients were less than 5 years, with 7% being under 2 years. Common frequent diagnoses were: aplastic/dysplastic kidneys (18%), obstructive uropathy (16%), and focal segmental glomerulosclerosis (12%). Preemptive transplant, i.e., transplantation without prior maintenance dialysis, was performed in 21% of the patients. Dialytic modalities pretransplant were peritoneal dialysis in 42% and hemodialysis in 25%. Bilateral nephrectomy was reported in 29%. Live-donor sources accounted for 42% of the transplants. Among cadaveric donors, 41% of the donors were under 11 years old. During the first post-transplant month, maintenance therapy was used similarly for live-donor and cadaver source transplants, with prednisone, cyclosporine, and azathioprine used in 93%, 83%, and 81%, respectively. Triple therapy with prednisone, cyclosporine, and azathioprine was used in 78%, 75%, and 75% of functioning cadaver source transplants at 6 months, 12 months, and 18 months as opposed to 60%, 63%, and 54% for live-donor procedures, with single-drug therapy being uncommon. Rehospitalization during months 1–5 occurred in 62% of the patients, with treatment of rejection and infection being the main causes. Additionally, 9% were hospitalized for hypertension. During months 6–12 and 12–17, 30% and 28% of the patients with functioning grafts were rehospitalized. Times to first rejection differed significantly for cadaver and live-donor transplants. The median time to the first rejection was 36 days for cadaver transplants and 156 days for live-donor transplants. Overall, 57% of treated rejections were completely reversible although the complete reversal rate decreased to 37% for four or more rejections. One hundred and fifty-two graft failures had occurred at the time of writing, with a 1-year graft survival estimate of 0.88 for live-donor and 0.71 for cadaver source transplants. In addition to donor source, recipient age is a significant prognostic factor for graft survival. Among cadaver donors, decreasing donor age is associated with a decreasing probability of graft survival. Thirty-five deaths have occurred; 16 attributed to infection and 19 to other causes. The current 1-year survival estimate is 0.94. There have been 9 malignancies.A list of all participating centers and the names of the investigators is printed on pages 552–553  相似文献   
5.
Abstract BT563, a murine anti-IL-2R MoAb, was found to be more potent than anti-Tac in inhibiting proliferation in the mixed lymphocyte reaction. Results obtained with 33 B3.1 in these experiments were similar to those with BT563. The anti-IL-2R MoAb 2A3 was shown to be a suitable agent for monitoring the effect of BT563 on peripheral blood. IL-2R-positive cells were not detected in peripheral blood samples from 1 h after the first dose until 8 days after the last dose. Plasma trough levels were measured in patients receiving 5 or 10 mg daily. The administration of BT563 to allograft recipients did not lead to clinically significant side effects.  相似文献   
6.
N-乙酰半胱氨酸对鼠肝超急性排斥反应的抑制作用   总被引:1,自引:1,他引:0  
目的:应用大鼠肝脏灌注模型研究N—乙酰半胱氨酸(NAC)对异种移植超急性排斥反应的抑制作用。方法:SD大鼠24只分为4组,每组6只,分为鼠血灌注组、人血灌注组、N—乙酰半胱氨酸(NAC)治疗鼠血灌注组、N—乙酰半胱氨酸(NAC)治疗人血灌注组。全麻下分离出胆总管、门静脉、肝上下腔静脉并插管,缺血30min后,原位灌注鼠肝2h,灌注过程按每30min收集胆汁,并监测灌注压力和动脉血气,在不同时间取血样检测脂质超氧化(MDA)、氮自由基(NO)、肝功能(Alt、Ast)。结果:异种灌注组,MDA、NO、的升高及Alt、Ast均明显高于对照组,胆汁流量明显减少;NAC的治疗抑制了异种灌注组MDA、NO的升高,Alt、Ast水平也明显低于对照组,胆汁流量明显增加,保护了肝脏功能。结论:自由基可能参与了异种移植的超急性排斥反应,NAC的治疗可部分抑制HAR,并保护大鼠异种移植的肝脏功能。  相似文献   
7.
Acute rejection, occurring with a reported frequency of 50–70%, is still a dominating problem after liver transplantation. Medication with ursodeoxycholic acid (UDCA) has beneficial effects in different cholestatic conditions and has also been shown to reduce HLA class I antigen expression on hepatocytes in patients with PBC. Since August 1989 we have consecutively treated all patients with primary graft function with UDCA (n = 41). Patients transplanted in the first half of 1989 served as a control group (n = 8). All patients in this study were given sequential quadruple drug immunosuppression. The treatment group were given oral UDCA 10 mg/kg per day. During the first postoperative month, 17% of the UDCA-treated patients had an episode of acute rejection compared with 75% of the control patients (P < 0.01). Liver biochemistry tests 1 month postoperatively were significantly better in patients treated with UDCA. The results suggest that adjuvant treatment with UDCA reduces acute liver graft rejection.  相似文献   
8.
Sprague-Dawley rats were ovariectomized and received bilateral sham, electrolytic or kainic acid lesions of the septum. Kainic acid lesions are purported to destroy cell bodies while not appreciably damaging fibers of passage or afferent terminals. Following priming with estradiol benzoate (EB), animals received three consecutive tests of lordosis and rejection behavior. Animals also received six tests of reactivity; one prior to each EB priming regimen and one following each lordosis and rejection test. Reactivity measures included resistance to capture and magnitude and quantity of startle responses. Electrolytic and kainic acid lesions were equivalent in facilitating lordosis. Although both lesions also increased rejection frequency, kainic acid effects were transient and markedly smaller by 60–80%. Reactivity data generally demonstrated significantly higher scores for kainic acid and electrolytic lesions groups and apparently time-dependent decreases in these scores. The results suggest that rejection behavior is not necessarily correlated with either lordosis or hyperreactivity.  相似文献   
9.
《Human immunology》2022,83(3):219-224
To date, traditional pre-transplant risk factors have failed to provide accurate risk stratification in transplantation. As a result, the practice of precision medicine remains elusive, resulting in a one-size-fits-all therapeutic approach for most patients. However, recent advancements in the understanding of HLA molecules at the molecular level have revitalized interest in HLA mismatch assessment. This review discusses HLA molecular mismatch as a potential prognostic and predictive biomarker available at the time of transplantation and answers some of the common questions and critiques of this approach. We highlight the retrospective data that supports single molecule risk categorization and explore the next steps required to evaluate its potential in clinical practice.  相似文献   
10.
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