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991.
目的探讨细胞色素P450药物代谢酶(CYP)2C19基因分型与氯吡格雷治疗的急性缺血性脑卒中患者再发脑卒中的关系。方法选取2018年5月—2018年12月常州市第一人民医院收治接受氯吡格雷治疗的159例急性缺血性脑卒中患者,检测患者入院后空腹外周血中CYP2C19*2,CYP2C19*3基因分型。对患者进行随访,随访截至2020年2月,观察再发脑卒中的情况,并分析CYP2C19*2,CYP2C19*3基因分型与再发脑卒中关系。结果随访时间14~22个月,平均随访时间为(18.2±1.5)个月,共7例患者失访,共20例(13.2%)患者复发缺血性脑卒中。再发脑卒中患者中CYP2C19*2 GG型及CYP2C19*3 GG型均低于无复发患者(P<0.05),CYP2C19*2 GA型,CYP2C19*2 AA型CYP2C19*3 GA型,CYP2C19*3AA型均高于无复发患者(P<0.05)。Kaplan-Meier法并Log-rank检验结果显示,CYP2C19*2 GG型无复发时间长于AA型,差异有统计学意义(Log-rank=6.759,P=0.034)。CYP2C19*3GG型无复发时间长于AA型,差异有统计学意义(Log-rank x2=8.660,P=0.013)。多因素Cox分析结果显示,糖尿病、氯吡格雷抵抗,CYP2C19*2及CYP2C19*3基因型是再发脑卒中影响因素(P<0.05)。结论在接受氯吡格雷治疗急性缺血性脑卒中患者中,CYP2C19*2及CYP2C19*3突变型再发脑卒中的风险明显增高。  相似文献   
992.
The objective of the study was to establish eliciting threshold concentrations of diazolidinyl urea (Germall II)– derived formaldehyde in formaldehyde and/or in diazolidinyl urea – sensitive patients, using a leave‐on face cream formulation in a repeated open application test (ROAT) applied to different anatomical regions.
150 patients with known formaldehyde allergy were reviewed for inclusion in the study. 108 patients were contacted and in 65 patients the formaldehyde sensitisation was reconfirmed by a patch test. Four groups of 10 formaldehyde allergic subjects were exposed to 0.05%, 0.15%, 0.3% and 0.6% diazolidinyl urea, corresponding to approximately 50, 100, 200 and 400 ppm free formaldehyde, respectively.
Additional 10 individuals allergic to the formaldehyde donor – diazolidinyl urea itself – were exposed to 0.15% diazolidinylurea, corresponding to approximately 100 ppm free formaldehyde and 10 healthy non‐allergic individuals were exposed to 0.6% of diazolidinylurea (approximately 400 ppm free formaldehyde).
A ROAT was performed in a scheduled sequence: upper arm, neck and face.
Contact allergy reactions were elicited in 39 out of 58 formaldehyde‐sensitive and in 5 out of 7 diazolidinyl urea‐sensitive individuals.
Elicitation responses were dose‐ and anatomical region – dependent.
No reactions were observed at the lowest dose, suggesting that an elicitation threshold was attained in the study.  相似文献   
993.
The patch test results of patients tested at least twice at our clinic during a period of 11 years were analyzed with regard to reproducibility of the positive patch test reactions found in the first patch testing session.
A retrospective analysis of 257 patients who have been tested with the TRUE Test at least twice between 1991 and 2002 and had a minimum of one positive reaction in the first testing session was done. Test reactions were read routinely after 3 and 5–7 days.
In the first testing session a total of 299 positive reactions were found. Of these allergens, 151 (51%) stayed positive in the second test, 31 (10%) produced a doubtful reaction, 67 (22%) a negative response, and 50 (17%) were not retested because of strong positive reactions in the first test. Of the individual allergens, positive reactions from thiuram‐mix, kathon CG and colophony were the most reproducible.
If it is assumed that allergens which were not retested because of strong positive reactions would have shown positive reactions in a retest, a total of 68% of positive reactions were reproduced. A multitude of factors, such as: avoidance of relevant allergens between tests, diminished sensitivity, retesting within a period of more or less active dermatitis, different observers, methodological error, and prior false‐positive responses, influence the reproducibility of patch tests. The results will be put in perspective.  相似文献   
994.
The dissemination of IgA-dependent immunity between mucosal sites has important implications for mucosal immunoprotection and vaccine development. Epithelial cells in diverse gastrointestinal and nonintestinal mucosal tissues express the chemokine MEC/CCL28. Here we demonstrate that CCR10, a receptor for MEC, is selectively expressed by IgA Ab-secreting cells (large s/cIgA(+)CD38(hi)CD19(int/-)CD20(-)), including circulating IgA(+) plasmablasts and almost all IgA(+) plasma cells in the salivary gland, small intestine, large intestine, appendix, and tonsils. Few T cells in any mucosal tissue examined express CCR10. Moreover, tonsil IgA plasmablasts migrate to MEC, consistent with the selectivity of CCR10 expression. In contrast, CCR9, whose ligand TECK/CCL25 is predominantly restricted to the small intestine and thymus, is expressed by a fraction of IgA Ab-secreting cells and almost all T cells in the small intestine, but by only a small percentage of plasma cells and plasmablasts in other sites. These results point to a unifying role for CCR10 and its mucosal epithelial ligand MEC in the migration of circulating IgA plasmablasts and, together with other tissue-specific homing mechanisms, provides a mechanistic basis for the specific dissemination of IgA Ab-secreting cells after local immunization.  相似文献   
995.
Circulating precursors of mucosal immunoglobulin A plasma cells and T-cell immunoblasts migrate selectively into mucosal sites from the blood, but the mechanisms controlling this selective trafficking have not been determined. One possibility is that the site-specific extravasation of circulating effector cell populations is determined by organ-specific endothelial cell recognition mechanisms. Here we have assessed the ability of isolated mouse gut intraepithelial lymphocytes to recognize and bind to mucosal versus nonmucosal lymphoid organ high endothelial venules, vessels that support high levels of lymphocyte traffic in vivo. In an in vitro assay of lymphocyte interaction with high endothelial venules in frozen sections, intraepithelial leukocytes bind well to high endothelial venules in Peyer's patches but, unlike most circulating B and T lymphocytes, are unable to interact with peripheral lymph node high endothelial venules. Furthermore, we show by in situ immunohistology and in cell suspension immunofluorescence studies that intraepithelial leukocytes fail to stain with a monoclonal antibody, MEL-14, against putative lymphocyte receptors for lymph node high endothelial venules. Thus, they lack a cell surface glycoprotein required for homing to peripheral nodes. The demonstration of organ-specific recognition of endothelial cells by a normal mucosal effector lymphocyte population suggests that selective interactions with endothelium may play an important role in controlling the distribution of effector cells in vivo. The utilization of organ-specific endothelial cell recognition mechanisms by circulating precursors of mucosal effector cells could explain both the unification of immune responses in diverse mucosal sites and the physiologic segregation of mucosal from nonmucosal immune mechanisms.  相似文献   
996.
Using monoclonal antibodies to spirochetal antigenes and lymphoid cell surface markers, we examined the synovial lesions of 12 patients with Lyme disease, and compared them with rheumatoid synovium and tonsillar lymphoid tissue. The synovial lesions of Lyme disease patients and rheumatoid arthritis patients were similar and often consisted of the elements found in normal organized lymphoid tissue. In both diseases, T cells, predominantly of the helper/inducer subset, were distributed diffusely in subsynovial lining areas, often with nodular aggregates of tightly intermixed T and B cells. IgD-bearing B cells were scattered within the aggregates, and a few follicular dendritic cells and activated germinal center B cells were sometimes present. Outside the aggregates, many plasma cells, high endothelial venules, scattered macrophages, and a few dendritic macrophages were found. HLA-DR and DQ expression was intense throughout the lesions. In 6 of the 12 patients with Lyme arthritis, but in none of those with rheumatoid arthritis, a few spirochetes and globular antigen deposits were seen in and around blood vessels in areas of lymphocytic infiltration. Thus, in Lyme arthritis, a small number of spirochetes are probably the antigenic stimulus for chronic synovial inflammation.  相似文献   
997.

Background

Despite the use of validated prehospital stroke scales, stroke mimics are frequent among patients transported by Emergency Medical Services to the Emergency Department. We aimed to describe the frequency and characteristics of neurological and non-neurological mimics transported to a comprehensive stroke center for acute stroke evaluation.

Methods

This was a retrospective analysis of a database consisting of all consecutive patients with suspected stroke transported to the Emergency Department of a comprehensive stroke center during an 18-month period. Hospital charts and neuroimaging were utilized to adjudicate the final diagnosis (acute stroke, stroke mimic, and specific underlying diagnoses).

Results

Nine hundred fifty patients were transported with suspected stroke, among whom 405 (42.6%) were stroke mimics (age 66.9 ± 17.1 years; 54% male). Neurological mimics were diagnosed in 223 (55.1%) patients and mimics were non-neurological in 182. The most common neurological diagnoses were seizures (19.7%), migraines (18.8%), and peripheral neuropathies (11.2%). Cardiovascular (14.6%) and psychiatric (11.9%) diagnoses were common non-neurological mimics. Patients with neurological mimics were younger (64.1 ± 17.3 years versus 70.5 ± 16.1 years, P < .001) and had less vascular risk factors than non-neurological mimics. The proportion of non-neurological mimics remained high (38%) despite the use of a prehospital stroke identification scale.

Conclusions

Stroke mimics are common among patients transported by Emergency Medical Services to a comprehensive stroke center for suspected stroke, with a considerable proportion being non-neurological in origin. Studies refining triage and transport of suspected acute stroke may be warranted to minimize the number of mimics transported by to a comprehensive stroke center for acute stroke evaluation.  相似文献   
998.
目的 探讨人脑胶质瘤血脑屏障(BBB)内皮细胞间紧密连接的变化及其可能的分子机制. 方法 将南方医科大学珠江医院神经外科自2008年至2009年切除的胶质瘤和正常脑组织标本分为3组:正常脑组织组(n=6)、低级别胶质瘤组(n=11)与高级别胶质瘤组(n=10),采用透射电镜观察标本BBB紧密连接的超微结构特征,应用免疫荧光双标染色和RT-PCR分别检测标本紧密连接蛋白Claudin-5和Claudin-5 mRNA的表达. 结果 电镜结果 显示正常脑组织微血管相邻内皮细胞间可见连续条带状的紧密连接.细胞间未见裂隙.低级别胶质瘤中多数微血管内皮细胞间可见连续的紧密连接,未见明显窗口形成.高级别胶质瘤中微血管内皮细胞间紧密连接破坏严重,内皮细胞间可见明显裂隙;免疫荧光双标染色结果 显示正常脑组织中微血管内皮细胞上有大量Claudin-5表达.低级别胶质瘤中微血管内皮细胞上Claudin-5表达略为下降,而高级别胶质瘤中微血管内皮细胞上无明显Clandin-5表达;RT-PCR结果 显示高级别胶质瘤Claudin-5 mRNA表达低于正常组脑组织和低级别胶质瘤,差异有统计学意义(P<0.05). 结论 在脑胶质瘤发生发展过程中.胶质瘤细胞可以导致BBB内皮细胞间紧密连接蛋白Claudin-5的表达下降及BBB紧密连接结构的破坏,而紧密连接蛋白Claudin-5这一分子元件的表达下降可能是紧密连接结构受到破坏的重要分子机制.  相似文献   
999.
目的 通过对注射用奥拉西坦与注射用吡拉西坦比较的临床研究,评价注射用奥拉西坦治疗颅脑损伤引起的神经功能缺失的临床疗效及安全性. 方法 本研究为随机、双盲、阳性药平行对照、多中心临床试验,收集自2006年9月至2009年1月珠江医院等5家医院收治的239例颅脑损伤和颅脑手术后患者,按照随机数字表法分为试验组(采用注射用奥拉西坦治疗,120例)和对照组(采用注射用吡拉西坦治疗,119例).比较2组治疗前后美国国立卫生研究院卒中量表(NIHSS)评分、GCS评分、肢体肌力分级、简易智能状态检查量表(MMSE)评分,观察2组的不良反应并进行心电图和实验室检查以了解其安全性. 结果 试验组和对照组NIHSS、GCS评分和肢体肌力分级治疗后较治疗前均有明显改善,差异有统计学意义(P<0.05),但改善的程度二者差异无统计学意义(P>0.05),且2组均无药物严重不良事件发生. 结论 注射用奥拉西坦与注射用吡拉西坦一样,在治疗颅脑损伤引起的神经功能缺失中疗效显著,安全性好.
Abstract:
Objective To evaluate the efficacy and safety of oxiracetam in the treatment of neurological deficits resulting from brain injury through the comparison of oxiracetam for injection and piracetam for injection in clinical trials. Methods A multiple-center, randomized, double-blind,parallel study was performed on 239 patients; these patients were divided into experimental group (oxiracetam for injection, n=120) and control group (piracetam, n=119). National institutes of health stroke scale (NIHSS), Glasgow coma scale (GCS), myodynamia grading, mini-metal state examination (MMSE) were employed to evaluate the therapeutic effects; electrocardiogram and laboratory examination were performed, and the side effects were also observed. Results The scores of NIHSS,GCS and myodynamia grading after treatment in the 2 groups were all significantly higher than those before treatment (P<0.05); however, no significant differences on these scores were noted between the experimental group and control group (P>0.05). No serious adverse events were noted in both groups.Conclusion Oxiracetam, the same as piracetam, is safe and effective in the treatment of neurological deficits secondary to brain injury.  相似文献   
1000.
目的 研究新型光敏剂ZnPcS4-BSA对光动力杀伤人神经胶质瘤细胞U251效应的影响,并对机制进行初步探讨. 方法 紫外光谱法观察U251细胞对ZnPcS4-BSA的摄取规律,确定最佳孵育时间;CCK-8法测定不同浓度ZnPcS4-BSA、不同剂量激光辐射对U251的细胞毒性和ZnPcS4-BSA介导光动力疗法(PDT)的最佳浓度和最佳激光剂量;应用20 μmol/L ZnPcS4-BSA作用U251细胞4h后给予100 J/cm2的激光辐射,以同样条件培养而未作PDT治疗的细胞作为对照,流式细胞术、RT-PCR分别检测细胞凋亡率和VEGF基因表达的变化. 结果 紫外光谱法扫描发现ZnPcS4-BSA作用4h后U251细胞摄取ZnPcS4-BSA的量达到峰值.不同浓度ZnPcS4-BSA处理后细胞生存率的差异无统计学意义(P>0.05).400J/cm2激光辐射后细胞生存率低于0、25、50、100、200J/cm2激光辐射组,差异有统计学意义(P<0.05).30 μmol/L ZnPcS4-BSA作用U251细胞4h后给予25、50、100、200 J/cm2激光照射,随着激光剂量的增加,细胞存活率降低,差异有统计学意义(P<0.05).20、40、60、80、100 μmol/L ZnPcS4-BSA作用U251细胞4h后,给予200J/cm2激光辐射,随着ZnPcS4-BSA浓度的增加,细胞的抑制率增加,差异有统计学意义(P<0.05).与对照组比较,经20μmol/L ZnPcS4-BSA作用,100 J/cm2的激光辐射后U251细胞凋亡率、VEGF基因的表达升高,差异均有统计学意义(P<0.05). 结论 新型光敏剂ZnPcS4-BSA具有良好的增强光动力效能,其介导的PDT能诱导细胞凋亡,其机制可能与VEGF基因有关.  相似文献   
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