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11.
Background: Glucocorticoids acting as anti-inflammatory or immunosuppressive drugs have been shown to exert most of their effects genomically. Recent findings suggest that non-genomic activity might be relatively more important in mediating the therapeutic effects of high-dose pulsed glucocorticoid. However, few non-genomic anti-inflammatory effects were reported, much less non-genomic mechanisms.Objective: This study was performed to investigate the nongenomic effects of glucocorticoids on human neutrophil degranulation.Methods: Purified human neutrophils were pretreated with 6 -methylprednisolone or hydrocortisone for 5 min, and then primed with N-formyl-methionyl-leucyl-phenylalanine (fMLP) (10–6 M) or phorbol myristate acetate (PMA) (50 ng/ml) in the presence of cytochalasin B. The release of two markers of neutrophil granules, lactoferrin and myeloperoxidase, was measured by ELISA and enzymology methods respectively.Results: Both 6 -methylprednisolone (10–5–10–4 M) and hydrocortisone (10–4 M) showed significant inhibitory effects on neutrophil degranulation within 5 min after fMLP administration. For PMA stimulated degranulation, 6 -methylprednisolone (10–4 M) showed significant inhibitory effects (p < 0.01), while hydrocortisone (10–4 M) only showed an inhibitory tendency (P > 0.05). Neither RU486 (10–5 M) nor cycloheximide (10–4 M) could alter the inhibitory effects of glucocorticoids.Conclusion: Our results demonstrate that megadoses of glucocorticoids exert rapid inhibitory effects on human neutrophil degranulation at the cellular level via a new mechanism that is independent of corticosteroid type II receptor occupation or protein synthesis. We infer that these effects may be very important when glucocorticoids act as anti-inflammatory drugs during pulse therapy.Received 20 May 2004; returned for revision 21 July 2004; accepted by M.J. Parnham 23 September 2004L. Liu and Y. X. Wang contributed equally to this work.  相似文献   
12.
目的 进行严重急性呼吸综合征 (SARS)的临床研究。方法 对 2 0 0 4年 4月 2 2日在地坛医院收治的 7例确诊SARS患者进行回顾性分析。结果  7例确诊SARS患者 ,男性 2例、女性 5例 ,年龄 2 0~ 4 9岁 ,平均年龄为 (35 3± 11 3)岁。临床症状主要表现为发热、咳嗽、不同程度的呼吸困难、全身不适、恶心、呕吐等 ,肺部可闻及湿音 ,可伴有肺外损伤。临床治疗中采用综合治疗原则 ,包括氧疗 ;小剂量、短期应用甲泼尼龙 ,剂量为每天 1~ 2mg kg;及时应用呼吸机 ;必要的心理干预及支持治疗等 ,患者均好转。结论 合理应用糖皮质激素 ,及时使用呼吸机是SARS治疗的关键。  相似文献   
13.
Ageing has been associated with increased cortisol levels and absolute counts of T lymphocytes with memory phenotype. Although the mechanisms underlying these changes are still unknown, it has been speculated that this could be related to a dysfunction in FAS/CD95 expression in naive or memory cells. In this study, we investigated the role of psychoneuroendocrine variables in regulating CD95 expression on lymphocyte subsets. Forty-six elderly subjects (65-91 years) and 33 young adults (20-40 years) were recruited accordingly the SENIEUR protocol. The psychological status was measured by structured clinical interviews, salivary cortisol was assessed along the day (9, 12 and 22h) and peripheral blood lymphocytes were immunophenotyped. The elderly were more stressed, depressed and anxious than the young subjects. Cortisol levels were increased in the elderly, indicating an activation of the hypothalamic-pituitary-adrenal (HPA) axis. We observed reduced counts of CD45RA+CD95+ cells in the elderly compared to young adults. The elderly subjects also showed a reduced expression of CD3 and CD62L in contrast to increased CD95 expression in CD45RA+ cells. The emotional state was positively correlated with the lymphocyte markers. Our data suggest the healthy ageing is associated with psychoneuroendocrine alterations that may be implicated in the regulation of CD95 expression on peripheral T cells.  相似文献   
14.
目的探讨儿童髓鞘少突胶质细胞糖蛋白(MOG)抗体相关炎性脱髓鞘疾病(IDD)患儿的临床表现、影像学特征、治疗方案及临床预后。 方法选择2014年6月1日至2020年9月30日,在中山大学孙逸仙纪念医院儿科确诊的7例MOG抗体相关IDD患儿为研究对象。其中,女性患儿为2例,男性为5例;平均年龄为8.3岁。回顾性分析该7例MOG抗体相关IDD患儿的临床特征、影像学检查结果、治疗方案及临床预后等。本研究遵循的程序符合2013年修订的《世界医学协会赫尔辛基宣言》要求。 结果①初诊时,这7例患儿分别被误诊为急性播散性脑脊髓炎(ADEM) (2例)、视神经炎(ON)(2例)、多发性硬化症(MS)(1例)、脑膜炎(1例)及自身免疫性脑炎(AE) (1例)。其中年龄较小患儿临床表现为ON症状,而年龄较大者为ADEM症状。②7例患儿中,2例脑脊液检查结果显示白细胞计数(WBC)增高、蛋白水平增高;而脑脊液MOG抗体呈阳性为6例,外周血抗CASPR-2抗体呈阳性为1例;6例患儿颅内压>200 mmH2O(1 mmH2O=0.098 1 kPa)。③7例患儿中,外周血WBC增高为2例,C反应蛋白(CRP)呈阳性为1例、红细胞沉降率(ESR)增高为1例。所有患儿外周血MOG抗体检测结果均呈阳性,而外周血抗CASPR-2抗体呈阳性为1例。④影像学检查结果显示,病变累及侧脑室周围为5例、基底节为3例,丘脑、脊髓和视神经各为2例,脑干和延髓各为1例,伴脑膜强化为1例;而且这7例患儿的病灶直径均>2 cm;年龄>5岁的3例患儿的病灶边界光滑、清晰。⑤治疗方案:1例患儿于急性期静脉输注甲泼尼龙10~30 mg/(kg·d)(每3天剂量递减1/2)+静脉注射免疫球蛋白(IVIG) 2 g/(kg·d)×1 d,6例静脉输注地塞米松[起始剂量为0.5 mg/(kg·d),序贯减量至泼尼松1 mg/(kg·d)口服维持治疗]+IVIG 0.4 g/(kg·d)× 5 d。治疗维持期内,对这7例患儿均进行泼尼松口服治疗,其中5例每个月静脉输注1剂IVIG,剂量为2 g/kg。对2例MOG抗体相关IDD复发患儿,均再次进行静脉输注甲泼尼龙+IVIG治疗,其中1例接受利妥昔单抗治疗的方案为375 mg/(m2·次)×1次/周×4周。治疗后,5例患儿获得完全恢复,2例部分恢复,平均年复发率(ARR)为0.40次/年。 结论MOG抗体相关IDD患儿的临床表现多样,早期易被临床误诊。MOG抗体可与AE相关抗体同时存在,影像学诊断可见多灶性病变。MOG抗体相关IDD虽为MOG抗体所介导,但是MOG抗原的免疫致病性,则与T、B淋巴细胞息息相关。MOG抗体对激素治疗敏感,即使在该病患儿多次复发的情况下,预后亦良好。  相似文献   
15.
The mechanisms underlying glucocorticoid-induced osteoporosis in humans are a defect in bone formation associated with increased bone resorption. The latter may be due to elevated parathyroid hormone (PTH) levels induced by the impairment of intestinal calcium absorption caused by corticosteroids. In this study we analysed the effects of corticosteroids in old ewes, a potential model for the study of human bone turnover. Two groups of seven 9-year-old female sheep were selected. The first group was injected intramuscularly with a daily dose of 30 mg methylprednisone (MP) during the first 2 months and 15 mg during the last month. After 2 and 3 months of treatment, blood samples were taken. At the end of the experiment the animals were slaughtered and the iliac crest kept for bone histomorphometry. Serum osteocalcin (sOC) rapidly and markedly decreased in the MP-treated group compared with controls (–77%;p<0.01). In contrast, at the end of the experiment serum calcium and PTH levels were similar in both groups. Histomorphometric analysis showed a significant reduction in the wall width of trabecular packets. Dynamic parameters reflecting bone formation at the tissue and cell levels were significantly lower in the MP-treated group than in controls, with a highly significant decrease in the mineralization rate (MAR: –63%,p<0.05) and double-labeled perimeter (dLPm/B.Pm: –92%p<0.05). The bone formation rate (BFR/B.Pm) also decreased by 84% and the adjusted apposition rate (Aj.AR) by 80%. The increase in the total formation period was mainly due to an increase in the inactive period. Significant correlations were found between sOC and MAR, dLPm/B.Pm and BFR/B.Pm (withr respectively 0.67, 0.76 and 0.51). In conclusion, the effects of corticosteroid on ewe bone remodeling are essentially characterized by a major bone formation defect without evidence of secondary hyperparathyroidism, although this cannot be totally excluded by our results. Ewes treated with glucocorticoids could represent a good model for evaluating the effects of drugs candidates for all bone conditions characterized by reduced bone formation resulting from osteoblastic depression.  相似文献   
16.
为探索应激和肾上腺切除在药物成瘾行为中的作用机制 , 将40只雄性Wista r大鼠随机分为肾上腺切除组、糖皮质激素Ⅰ组(肾上腺切除+氢化考的松20mg/kg)、糖皮质激素Ⅱ组(肾上腺切除+氢化考的松40mg/kg)及生理盐水对照组,每组各10只, 观察肾上腺切除及给予糖皮质激素对强迫游泳大鼠条件性位置偏爱形成的影响.结果: ①肾上腺切除组动物在药物搭配侧箱体中停留的时间与在对侧箱体中停留时间相比无明显差异(t=1.84 , P>0.05),而其它3组中均存在显著性差异(P<0.05或P<0.01);②与其它3 组相比,肾上腺切除组动物在药物搭配侧箱体中停留时间明显缩短,而其它3组之间则无明显差异.由此表明,切除肾上腺能够减弱强迫游泳对大鼠吗啡条件性位置偏爱的强化作用, 而给予外源性糖皮质激素能够逆转这种作用.  相似文献   
17.
目的 观察不同剂量的糖皮质扩素对重症支气管哮喘的疗效。方法 观察组16例采用小剂量激素(地塞米松20mg/d)治疗,对照组16例使用较大量激素(地塞米松40mg/d)治疗。基他治疗措施及方法基本桢。结果 两组病人症状均在1~2d缓解,动脉血PaO2恢复正常所需时间两组无差异(P〉0.05)。结论 对重症哮喘者早期应用小剂量激素、氩茶碱持续静脉点滴,可避免大剂量应用产生的副作用,可收到较好效果。  相似文献   
18.
肝素与糖皮质激素在急性肺损伤中的治疗对比   总被引:3,自引:0,他引:3  
曹慧玲  杨宁江 《吉林医学》2000,21(5):290-291
目的 :了解急性肺损伤 (AL I)常见治疗中肝素与糖皮质激素对炎细胞的影响。方法 :用油酸尾静脉注射制作小鼠AL I损伤模型 ,观察其周围血白细胞及肺组织病理改变。结果 :AL I时肺系数损伤组明显高于除肝素组的其他组 ,周围血中性粒细胞 /淋巴细胞 (N/L)比率在 AL I时明显增加 ;肝素组在损伤 6 h后可见 N/L 降低 ,糖皮质激素则使其增高。组织切片见激素治疗组中每高倍视野内的多形核细胞数 (PMN)、肺水肿程度明显低于肝素组与损伤组 ;肝素治疗组中虽然肺水肿程度与损伤组无差异 ,但微小血栓明显少于损伤组与激素组。结论 :激素通过抑制 PMN在肺内的聚集而减少肺损伤 ;肝素则通过调节凝血机制保护肺脏  相似文献   
19.
Summary To examine the influence of adrenal secretions on neuroleptic induced catalepsy, we studied the effect of adrenocorticoids, noradrenaline (NA) or adrenaline (AD) on haloperidol (HAL) induced catalepsy in adrenalectomised (ADX) and sham-adrenalectomised (sham-ADX) rats. HAL (1 mg/kg, i.p.) induced a greater degree of catalepsy in ADX rats as compared to sham-ADX rats. Corticosterone (CORT, 1–2 mg/kg, s.c.) or dexamethasone (1–2 mg/kg, s.c.) attenuated the HAL catalepsy in sham-ADX but not in ADX rats. Further, when the HAL (1 mg/kg) catalepsy score was maximal (at 120 min), the rats were subjected to cold stress (3 °C for 10 min) or treated with NA, AD (2 g/kg, i.v.) or CORT (2 mg/kg, s.c.). After cold stress procedure or CORT treatment, the catalepsy was significantly reduced in sham-ADX but not in ADX rats, whereas NA or AD infusion caused an immediate but short lasting significant decrease in HAL catalepsy in both sham-ADX and ADX rats. The anticataleptic effect of NA or glucocorticoids was blocked by an 1adrenoceptor blocker, prazosin.These findings suggest that peripheral noradrenergic and adrenergic mechanisms play an important role in the neuroleptic induced catalepsy. Such mechanisms may mediate the anticataleptic action of glucocorticoids.  相似文献   
20.
目的:探讨糖皮质激素治疗流行性乙型脑炎的疗效。方法:采用地塞米松针剂加入液体静脉滴注,并配合物理降温、镇静止痉、脱水、给氧、扩容、纠酸、防治感染,加强护理等常规综合治疗。结果:治愈69例(908%),好转3例(39%),死亡4例(53%)。结论:在常规综合治疗基础上应用激素治疗乙型脑炎疗效显著提高。  相似文献   
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