全文获取类型
收费全文 | 403篇 |
免费 | 34篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 2篇 |
基础医学 | 57篇 |
口腔科学 | 33篇 |
临床医学 | 43篇 |
内科学 | 75篇 |
皮肤病学 | 1篇 |
神经病学 | 87篇 |
特种医学 | 17篇 |
外科学 | 36篇 |
综合类 | 2篇 |
预防医学 | 30篇 |
眼科学 | 19篇 |
药学 | 23篇 |
中国医学 | 1篇 |
肿瘤学 | 10篇 |
出版年
2018年 | 3篇 |
2017年 | 5篇 |
2016年 | 8篇 |
2015年 | 10篇 |
2014年 | 12篇 |
2013年 | 16篇 |
2012年 | 20篇 |
2011年 | 19篇 |
2010年 | 7篇 |
2009年 | 7篇 |
2008年 | 15篇 |
2007年 | 17篇 |
2006年 | 14篇 |
2005年 | 8篇 |
2004年 | 16篇 |
2003年 | 15篇 |
2002年 | 16篇 |
2001年 | 14篇 |
2000年 | 9篇 |
1999年 | 8篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1995年 | 3篇 |
1993年 | 3篇 |
1992年 | 14篇 |
1991年 | 5篇 |
1990年 | 6篇 |
1989年 | 5篇 |
1988年 | 5篇 |
1987年 | 7篇 |
1986年 | 10篇 |
1985年 | 4篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1981年 | 5篇 |
1979年 | 3篇 |
1978年 | 4篇 |
1977年 | 6篇 |
1972年 | 3篇 |
1971年 | 5篇 |
1970年 | 3篇 |
1969年 | 6篇 |
1968年 | 3篇 |
1967年 | 10篇 |
1966年 | 17篇 |
1965年 | 10篇 |
1962年 | 3篇 |
1961年 | 4篇 |
1959年 | 4篇 |
1924年 | 3篇 |
排序方式: 共有437条查询结果,搜索用时 640 毫秒
1.
Elevated expression in situ of selectin and immunoglobulin superfamily type adhesion molecules in retroocular connective tissues from patients with Graves' ophthalmopathy. 总被引:11,自引:1,他引:11
下载免费PDF全文
![点击此处可从《Clinical and experimental immunology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Activation of certain adhesion molecules within vascular endothelium and the surrounding extravascular space is a critical event in the recruitment and targeting of an inflammatory response or autoimmune attack to a particular tissue site. We have recently demonstrated that the adhesion of lymphocytes to cultured retroocular fibroblasts obtained from patients with Graves' ophthalmopathy (GO) is mediated predominantly by the interaction of lymphocyte function-associated antigen-1 (LFA-1), expressed on lymphocytes, with intercellular adhesion molecule-1 (ICAM-1), expressed by these cells following exposure to interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha), IL-1 alpha or purified thyroid-stimulating immunoglobulins. We now report the expression and localization in situ of several adhesion molecules, ICAM-1, endothelial leucocyte adhesion molecule-1 (ELAM-1), vascular cell adhesion molecule-1 (VCAM-1), and LFA-3 in retroocular tissues derived from patients with severe GO (n = 4) and normal individuals (n = 3). Serial cryostat sections of tissue specimens were processed for immunoperoxidase staining using various MoAbs against ICAM-1, ELAM-1, VCAM-1 and LFA-3. In addition, consecutive sections were stained with MoAbs against LFA-1, CD45RO (UCHL-1)DR-human leucocyte antigen (HLA-DR), CD11b/CD18 (Mac-1), and CD11c/CD18 (p150,95). In GO-retroocular tissues, strong immunoreactivity for ICAM-1 and LFA-3 was detected in blood vessels (> 90%), in perimysial fibroblasts surrounding extraocular muscle fibres, and in connective tissue distinct from extraocular muscle. No ICAM-1 or LFA-3 immunoreactivity was present in extraocular muscle cells themselves. ICAM-1 and LFA-3 immunoreactivity in normal tissues was minimal or absent both in connective and muscle tissues. Vascular endothelium was strongly positive for ELAM-1 and VCAM-1 in GO-retroocular tissues, while VCAM-1 immunoreactivity was minimal (< 5% of blood vessels) and ELAM-1 immunoreactivity was generally absent in normal retroocular tissue. LFA-1-expressing, activated mononuclear cells and memory T lymphocytes (CD3+/CD45RO+) were only detected in GO-retrocular tissues, and were mainly localized around blood vessels and in areas of ICAM-1-expressing connective and perimysial tissue. HLA-DR expression was restricted to GO-tissue specimens, with strong immunoreactivity detected in blood vessels, macrophages and connective tissue and perimysial fibroblasts. No HLA-DR was detectable in extraocular muscle cells. In conclusion, infiltration of the orbit in GO by mononuclear cells, and their targeting within the orbit, may depend upon the coordinate expression of certain adhesion and MHC molecules.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
2.
Protective effect of Hypericum perforatum Linn (St. John's wort) against hydrogen peroxide-induced apoptosis on human neuroblastoma cells 总被引:3,自引:0,他引:3
Jang MH Lee TH Shin MC Bahn GH Kim JW Shin DH Kim EH Kim CJ 《Neuroscience letters》2002,329(2):177-180
The medicinal plant Hypericum perforatum Linn, commonly known as St. John's wort, has been used as an antidepressant. To investigate whether St. John's wort possesses a protective effect against hydrogen peroxide (H(2)O(2))-induced cytotoxicity in neuronal cells, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, 4,6-diamidino-2-phenylindole staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay, flow cytometry analysis, DNA fragmentation assay, and caspase-3 enzyme assay were performed on SK-N-MC human neuroblastoma cells. Cells treated with H(2)O(2) exhibited several apoptotic features, while those pre-treated with St. John's wort prior to H(2)O(2) exposure showed a decreased occurrence of apoptotic features. In addition, pre-treatment with St. John's wort inhibited H(2)O(2)-induced increase in caspase-3 enzyme activity. These results suggest that St. John's wort may exert a protective effect against H(2)O(2)-induced apoptosis in human neuroblastoma cells. 相似文献
3.
R K Brown D K Bahn B L Walters J J Karazim A A Reidinger K Y Shei A W Morgan D B Hurd H Gontina G A Kling 《Clinical nuclear medicine》1990,15(1):11-15
Forty patients with acute onset renal colic were studied using technetium-99m DTPA renal scintigraphy. Thirty-two were found to have varying degrees of obstruction. In the obstructed group the level was determined by the scan alone in 24 of 32 cases (75%). When the analysis included an abdominal radiograph, the level of obstruction was ascertained in 29 of 32 cases (91%). A delayed nephrogram, as evidenced by an "empty renal pelvis sign" at 5 minutes, was observed in all but one of the cases of obstruction (97%). Delayed clearance of activity from the pyelocalyceal system or ureter was also seen in 97%. In all cases of obstruction either one or both of these signs were observed. However, delayed clearance was found to be a nonspecific finding and was noted in 25% of nonobstructed cases. The finding of the "empty renal pelvis sign" at 5 minutes was found to be specific and was not seen in the nonobstructed group. The authors conclude that radionuclide renal scanning is an effective method for evaluating selected patients with suspected renal colic. 相似文献
4.
Rainov Nikolai G. Dobberstein Karl-Ulrich Bahn Hannes Holzhausen Hans-Jürgen Lautenschläger Christine Heidecke Volkmar Burkert Winfried 《Journal of neuro-oncology》1997,35(1):13-28
Despite the use of multimodal therapy, higher-grade glioma is stilluniformly fatal in the adult population. There is a considerable differencebetween the length of survival in each given patient, even within the sametumor type and malignancy grade group, suggesting that there are factorsthat might differentially influence outcome. To identify such factors, 107patients with anaplastic or malignant glioma were retrospectivelyinvestigated. Clinical parameters and paraclinical data on the p53, mdm2,and EGFR genes at the DNA or protein level were evaluated by univariateanalysis and Cox proportional hazards regression modeling. Kaplan-Meiersurvival estimation demonstrated that immunohistochemical positivity formdm2 protein in patients with anaplastic astrocytoma or with glioblastomamultiforme was associated with a shorter survival time (p = 0.02).P53 gene mutations and immunopositivity for the epidermal growth factorreceptor (EGFR) protein were not significantly related to poor prognosis.The Cox proportional hazards model revealed immunohistochemical positivityfor p53, mdm2, or for both of them, the presence of postoperativeirradiation, and the extent of surgical resection of tumor to be variablessignificantly associated with prolonged survival. EGFR overexpression, ageover 60 years, and Karnofsky performance score below 40 points did notsignificantly shorten survival time. In conclusion, the present studyidentified immunohistochemically detected mdm2-protein overexpression as astatistically significant negative prognostic parameter in patients bearinganaplastic or malignant glioma. Association analysis of variables revealed apossible correlation between mdm2 and p53, which is also consistent with thebiological interaction mode of both proteins in vivo. 相似文献
5.
H. von Piekartz E. Stotz A. Both G. Bahn S. Armijo‐Olivo N. Ballenberger 《Journal of oral rehabilitation》2017,44(12):964-973
The primary objective of this study was to determine the structural and known‐group validity as well as the inter‐rater reliability of a test battery to evaluate the motor control of the craniofacial region. Seventy volunteers without TMD and 25 subjects with TMD (Axes I) per the DC/TMD were asked to execute a test battery consisting of eight tests. The tests were video‐taped in the same sequence in a standardised manner. Two experienced physical therapists participated in this study as blinded assessors. We used exploratory factor analysis to identify the underlying component structure of the eight tests. Internal consistency (Cronbach's α), inter‐rater reliability (intra‐class correlation coefficient) and construct validity (ie, hypothesis testing‐known‐group validity) (receiver operating curves) were also explored for the test battery. The structural validity showed the presence of one factor underlying the construct of the test battery. The internal consistency was excellent (0.90) as well as the inter‐rater reliability. All values of reliability were close to 0.9 or above indicating very high inter‐rater reliability. The area under the curve (AUC) was 0.93 for rater 1 and 0.94 for rater two, respectively, indicating excellent discrimination between subjects with TMD and healthy controls. The results of the present study support the psychometric properties of test battery to measure motor control of the craniofacial region when evaluated through videotaping. This test battery could be used to differentiate between healthy subjects and subjects with musculoskeletal impairments in the cervical and oro‐facial regions. In addition, this test battery could be used to assess the effectiveness of management strategies in the craniofacial region. 相似文献
6.
Jingti Deng Jonathan R. Lamb Astrid P. Mckeown Sam Miller Pierandrea Muglia Paul C. Guest Sabine Bahn Enrico H. Domenici Hassan Rahmoune 《Journal of affective disorders》2013
Background
Changes in circulatory aminopeptidases [dipeptidyl-peptidase-IV (DPP-IV), Prolyl-oligopeptidase (POP) and Leucine aminopeptidase (LAP)] activities have been found to be associated with psychiatric illnesses and inflammatory diseases.Methods
The discriminatory indices of aminopeptidases activities were assessed by enzymatic assays in plasma samples from 240 unipolar depression (UD) patients and 264 matched controls. In addition the relationship between soluble and cellular DPP-IV activity was determined in plasma and blood cells from healthy subjects.Results
Greater than 95% of the plasma DPP-IV activity could be blocked by inhibitors, demonstrating the specificity of the assay. Also, DPP-IV protein and activity levels were strongly correlated. In contrast, only 50% of the membrane-bound activity in blood cells was inhibited, which suggested that other similar peptidases may be present in these cells. UD patients had decreased plasma levels of DPP-IV and POP activities compared to healthy controls with a concomitant increase in LAP activity. Finally, testing of the LAP/DPP-IV ratio resulted in good discrimination of UD patients from controls with an area under the curve—receiver operating characteristic of 0.70.Limitations
Further biological validation studies using different cohorts are warranted.Conclusions
The finding that plasma DPP-IV activity was decreased and LAP activity was increased in UD patients suggests the potential value for testing the levels of these enzymes for improved classification of patients. In addition, the changes in these enzymes, suggests that the proteolytic maturation of their proneuropeptide and prohormone subtrates may also be affected in UD, resulting in altered production of the associated bioactive peptides. 相似文献7.
Hemostatic plug (HP) formation was investigated in the ear bleeding time incision in normal and von Willebrand pigs. HP volume was calculated by integrating the areas of serial sections. In normal pigs (n = 11), platelets immediately formed a layer on the surface of the cut channel. Platelet aggregates formed at the ends of transected vessels and gradually enlarged. Finally, all transected vessels were occluded by HP and bleeding stopped. In contrast, large HPs were formed in the incision in von Willebrand's disease (vWD) pigs (n = 4); these HPs did not cover the ends of the transected vessels, which continued to bleed, allowing the formation of large hemostatically ineffective platelet aggregates in the incision. Canals traversed these HPs, and bleeding from the open vessels may have continued through them. After infusion of cryoprecipitate into a vWD pig, the bleeding time shortened, and the morphological findings of the HPs were similar to those of normal pigs. In normal pigs (n = 3) infused with an anti- Willebrand factor monoclonal antibody, which prolonged the bleeding time, a large HP formed in the incision, similar to that observed in the vWD pig. The volume of the normal and vWD HPs increased with time. These in vivo findings suggest that Willebrand factor is involved in the localization of the HP to the damaged vessel and may also play a role in platelet-platelet interaction. A computerized morphometric technique was used for measuring the volume of the hemostatic plugs and the distance of sequential points on the perimeter of the HP from the center of selected bleeding vessels. 相似文献
8.
Bahn D 《Nurse education today》2007,27(7):723-730
The aim of this exploratory study was to gain information on the current orientation of registered nurses towards continuing education and lifelong learning. The population (N=162) consists of 2nd and 1st Level nurses who have or are currently taking part in continuing education. Qualitative empirical data were obtained through semi structured one to one interviews. The research questions sought information related to some of the reasons and motives for the participants' taking part in various categories of learning. Also explored was what factors might influence these participants' learning activities and the views and perceptions of their learning experiences. For many of these nurses, the initial motive for taking part in continuing education was the perception that they were being left behind by the higher educational level of nurses entering the profession. Contrary to some anecdotal views, the participants generally felt that higher education (HE) contributed to enhanced client care, reporting additional personal and professional satisfaction. Alleged poor support from managers for continuing education and the lack of parity, often within the same organisation regarding the selection criteria to take part in a variety of learning activities, was a source of dissatisfaction for some of these participants. Their determination to learn, however, remained strong. 相似文献
9.
Emanuel Schwarz Nico J. M. van Beveren Jordan Ramsey F. Markus Leweke Matthias Rothermundt Bernhard Bogerts Johann Steiner Paul C. Guest Sabine Bahn 《Schizophrenia bulletin》2014,40(4):787-795
Schizophrenia is a heterogeneous disorder normally diagnosed using the Diagnostic and Statistical Manual of Mental Disorders criteria. However, these criteria do not necessarily reflect differences in underlying molecular abnormalities of the disorder. Here, we have used multiplexed immunoassay analyses to measure immune molecules, growth factors, and hormones important to schizophrenia in acutely ill antipsychotic-naive patients (n = 180) and matched controls (n = 398). We found that using the resulting molecular profiles, we were capable of separating schizophrenia patients into 2 significantly distinct subgroups with predominant molecular abnormalities in either immune molecules or growth factors and hormones. These molecular profiles were tested using an independent cohort, and this showed the same separation into 2 subgroups. This suggests that distinct abnormalities occur in specific molecular pathways in schizophrenia patients. This may be of relevance for intervention studies that specifically target particular molecular mechanisms and could be a first step to further define the complex schizophrenia syndrome based on molecular profiles.Key words: schizophrenia, subtypes, diagnosis, molecular profiling, immune factors, growth factors 相似文献
10.
Directing gene expression to cerebellar granule cells using γ-aminobutyric acid type A receptor α6 subunit transgenes
下载免费PDF全文
![点击此处可从《Proceedings of the National Academy of Sciences of the United States of America》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Sabine Bahn Alison Jones William Wisden 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(17):9417-9421
Expression of the γ-aminobutyric acid type A receptor α6 subunit gene is restricted to differentiated granule cells of the cerebellum and cochlear nucleus. The mechanisms underlying this limited expression are unknown. Here we have characterized the expression of a series of α6-based transgenes in adult mouse brain. A DNA fragment containing a 1-kb portion upstream of the start site(s), together with exons 1–8, can direct high-level cerebellar granule cell-specific reporter gene expression. Thus powerful granule cell-specific determinants reside within the 5′ half of the α6 subunit gene body. This intron-containing transgene appears to lack the cochlear nucleus regulatory elements. It therefore provides a cassette to deliver gene products solely to adult cerebellar granule cells. 相似文献