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91.
Ne?e Colak Ozbey Yersu Kapran Alp Bozbora Ye?im Erbil Cemil Tascioglu Sylvia L. Asa 《Endocrine pathology》2009,20(2):127-132
Ectopic secretion of growth hormone-releasing-hormone (GHRH) is a rare cause of acromegaly—representing less than 1% of patients.
A 25-year-old woman was admitted to the hospital with acromegaly and a 6 × 6 cm infrahepatic mass. Sellar magnetic resonance
imaging indicated diffuse pituitary enlargement consistent with hyperplasia. The infrahepatic mass was resected, and the histopathological
diagnosis was a well-differentiated invasive neuroendocrine carcinoma of the duodenum with metastases to local lymph nodes.
The tumor cells contained cytoplasmic immunoreactivity for GHRH. Because increased IGF-1 concentrations persisted after the
operation, the patient was treated with octreotide long-acting repeatable (LAR) injections of 20 mg/month. Growth hormone
and IGF-1 levels normalized. After 6 years of surveillance, a left paraaortic mass was detected by uptake of indium111 octreotide. Surgical exploration revealed metastatic neuroendocrine carcinoma in a 2.5-cm lymph node. Postoperatively, the
IGF-1 concentration was mildly elevated. Octreotide LAR therapy is being continued at 10 mg/month. This case suggests that
octreotide treatment may have a beneficial effect on disease course and can be maintained for as long as 7 years in a patient
with acromegaly due to a GHRH-secreting neuroendocrine carcinoma. 相似文献
92.
Bartonek A Eriksson M Gutierrez-Farewik EM 《Developmental medicine and child neurology》2007,49(8):615-620
A consecutive series of 17 children (six males, 11 females; mean age 11y 11mo [SD 4y 5mo]; range 3y 11mo-17y 4mo) with plantarflexor weakness was assessed to compare gait differences between a carbon fibre spring orthosis (CFSO) and participants' regular orthoses. Twelve children had myelomeningocele, four children had arthrogryposis, and one child had neuropathy with peripheral muscle pareses. All participants underwent clinical examination and 3D gait analysis. Parents answered a questionnaire to assess subjective perceptions of the orthoses. Results from 3D gait analysis provided evidence that CFSOs enhance gait function in most participants by improving ankle plantarflexion moment (p<0.001), ankle positive work (p<0.001), and stride length (p<0.001). The CFSO did not suit all participants, which emphasizes the importance of analyzing each patient's needs. 相似文献
93.
Keita AV Stertman L Sun YQ Larhed A Sjöholm I Söderholm JD 《Journal of neuroimmunology》2007,183(1-2):33-42
Uptake of antigens and bacteria over the follicle-associated epithelium (FAE) is increased after chronic psychological stress. We investigated whether stress affects the immune response to particle-conjugated antigens taken up via the FAE. Rats were submitted to two 10-day periods of water avoidance stress and orally immunized during these periods. Stressed immunized rats displayed altered cell populations and a Th1-skewed immune response within the lymphoid follicles, together with enhanced delayed-type hypersensitivity. We conclude that chronic stress affects the cell-mediated immune response after oral immunization, which may have implications for the understanding of allergic and autoimmune diseases and development of oral vaccines. 相似文献
94.
The use of alcohol and medications among Swedish widows was analyzed in relation to various background variables. In Total, 1053 widows (640 widows younger than 65 years and 413 widows older than 65 years) answered the questionnaire. Many reported increased fatigue and sleeping problems. Around one-third of the widows reported drinking alcohol for relief of grief and inadequate support. Association existed between grief and increased intake of sedatives and sleeping pills, and between grief and drinking for relief of grief, as well as increase in intake of sedatives. In widows older than 65 years, perception of bad health, negative outlook for the future, and insufficient support seemed to increase the risk of more sedatives and sleeping pills. Negative outlook for the future also tended to lead to a heightened risk for increased intake of alcohol. There seems to be remaining health problems a long time after bereavement, and counseling may be needed especially when drugs and alcohol are extensively used. 相似文献
95.
Developmental Changes in PON1 Enzyme Activity in Young Children and Effects of PON1 Polymorphisms 下载免费PDF全文
Karen Huen Kim Harley Jordan Brooks Alan Hubbard Asa Bradman Brenda Eskenazi Nina Holland 《Environmental health perspectives》2009,117(10):1632-1638
Background
Paraoxonase 1 (PON1) is an enzyme that detoxifies activated organophosphorus pesticides (OPs) and is also involved in oxidative stress pathways.Objectives
PON1 activity in newborns is lower than in adults, but the ontogeny of PON1 activity is poorly characterized in young children. We examined the effects of age and PON1 genotype on enzyme activity in a birth cohort of Mexican-American children.Methods
We determined three substrate-specific measures of PON1 activity in 1,143 plasma samples collected longitudinally from 458 children at five time points from birth through 7 years of age, and genotyped PON1 polymorphisms at positions 192 and –108 in these children.Results
Contrary to previous reports that PON1 activities plateau by 2 years of age, we observed an age-dependent increase in all three PON1 measures from birth through 7 years of age (p < 0.0001). The PON1192 genotype significantly modified the effect of age on paraoxonase (POase) activity (p < 0.0001) such that increases in enzyme activity with age were influenced by the number of R alleles in a dose-dependent manner. Children with the PON1-108CC192RR diplotype had significantly higher mean PON1 activities and also experienced steeper increases of POase activity over time compared with children with the PON1-108TT192QQ diplotype.Conclusions
Lower levels of the PON1 enzyme, which is involved in protection against OPs and oxidative stress, persist in young children past 2 years of age through at least 7 years of age. Future policies addressing pesticide exposure in children should take into account that the window of vulnerability to OPs in young children may last beyond infancy. 相似文献96.
Loss of membrane localization and aberrant nuclear E-cadherin expression correlates with invasion in pancreatic endocrine tumors 总被引:5,自引:0,他引:5
Decrease in E-cadherin is considered a molecular event in dysfunction of the cell-cell adhesion system, triggering invasion and metastasis in many malignancies, including those of endocrine origin. In addition, alterations in the cadherin-catenin system may also be involved in tumorigenesis. E-cadherin and beta-catenin, components of the Wnt signal transduction pathway, may serve as a common switch in central processes that regulate cellular differentiation and growth. The purpose of this study was to examine if abnormalities of the Wnt signaling pathway, specifically, E-cadherin and beta-catenin, occur in pancreatic endocrine tumors (PETs) and correlate these with clinicopathologic parameters. Tissue microarrays were constructed from 57 cases with 4 to 14 cores measuring 1.0 mm from each case. Size of tumor, presence or absences of necrosis, gross invasiveness/demarcation, lymphovascular invasion, and lymph node involvement and liver metastasis were recorded. The mitotic count, expressed per 50 high power fields (HPF) and MIB-1 index of the entire tumor were assessed. All the tissue microarray blocks were stained with commercially available antibodies to E-cadherin (cytoplasmic and extracellular domains), beta-catenin, APC, and GSK-3beta. Twenty-seven were male patients and 30 female, ranging in age from 23 to 80 years (mean, 51.7 y). Six patients had MEN1 syndrome and 1 von Hippel Lindau disease. The tumors ranged in size from 0.8 to 9.8 cm with a mean of 3.4 cm. Sixteen patients had lymph node spread and 7 had liver metastasis. The Ki-67 labeling index ranged from 1% to 30% and the mitotic counts from 0 to 27 per 50 HPF. Thirty of 57 cases (52.6%) cases showed abnormal beta-catenin expression. Thirteen of the 16 cases with lymph node metastasis and all 7 cases with liver spread showed abnormalities of beta-catenin immunostaining. Only 2 cases showed nuclear beta-catenin. The average size of tumors with beta-catenin abnormalities was 4.8 cm. Thirty-four of the 57 (59.6%) cases showed loss of normal membranous immunoreactivity for both antibodies E-cadherin, including nuclear localization in 18 cases with the antibody that recognizes the cytoplasmic domain. E-cadherin decrease and/or loss was identical to beta-catenin with the same 13 cases showing nodal involvement and all 7 cases with liver metastasis displaying aberrant E-cadherin staining. Seven of the 18 cases with nuclear E-cadherin had lymph node spread and 3 liver metastases. The mean size of the 34 cases with abnormal E-cadherin expression was 4.4 cm, compared to the series mean of 3.4 cm. Interestingly, cases with nuclear E-cadherin had a mean size of 5.2 cm. beta-catenin and E-cadherin abnormalities did not correlate with other clinicopathological parameters. All 57 cases showed cytoplasmic immunoreactivity for APC, and cytoplasmic and nuclear positivity for GSK-3beta. APC and GSK-3beta did not show any correlation with beta-catenin or E-cadherin staining.Abnormalities of beta-catenin and E-cadherin immunoexpression are seen in the majority of PETs. Nuclear beta-catenin is rare in PET but nuclear E-cadherin, a previously unrecognized staining pattern in PETs was seen 18 of 57 cases with the antibody detecting the cytoplasmic fragment of E-cadherin. Aberrant expression of both beta-catenin and E-cadherin correlated strongly with lymph node spread and liver metastases. 相似文献
97.
Cellular origin and environmental cues regulate stem cell fate determination. Neuroepithelial stem cells form the central nervous system (CNS), whereas neural crest stem cells generate the peripheral (PNS) and enteric nervous system (ENS). CNS neural stem/progenitor cell (NSPC) fate determination was investigated in combination with dissociated cultures or conditioned media from CNS, PNS, or ENS. Cells or media from ENS or PNS cultures efficiently promoted NSPC differentiation into neurons, glia, and smooth muscle cells with a similar morphology as the feeder culture. Together with CNS cells or its conditioned medium, NSPC differentiation was partly inhibited and cells remained immature. Here, we demonstrate that secreted factors from the environment can influence CNS progenitor cells to choose a PNS-like cell fate. 相似文献
98.
Rohrmann S Becker N Linseisen J Nieters A Rüdiger T Raaschou-Nielsen O Tjønneland A Johnsen HE Overvad K Kaaks R Bergmann MM Boeing H Benetou V Psaltopoulou T Trichopoulou A Masala G Mattiello A Krogh V Tumino R van Gils CH Peeters PH Bueno-de-Mesquita HB Ros MM Lund E Ardanaz E Chirlaque MD Jakszyn P Larrañaga N Losada A Martínez-García C Agren A Hallmans G Berglund G Manjer J Allen NE Key TJ Bingham S Khaw KT Slimani N Ferrari P Boffetta P Norat T Vineis P Riboli E 《Cancer causes & control : CCC》2007,18(5):537-549
Introduction Lymphomas are a heterogeneous group of malignant diseases of cells of the immune system. The best-established risk factors
are related to dys-regulation of immune function, and evidence suggests that factors such as dietary or lifestyle habits may
be involved in the etiology.
Material and methods In the European Prospective Investigation into Cancer and Nutrition (EPIC), 849 lymphoma cases were identified in a median
follow-up period of 6.4 years. Fruit and vegetable consumption was estimated from validated dietary questionnaires. Cox proportional
hazard models were used to examine the association between fruit and vegetable intake with the risk of lymphomas overall and
subentities.
Results There was no overall association between total fruit and vegetable consumption and risk of lymphoma [hazard ratio (HR) = 0.95,
95% confidence interval (CI) 0.78–1.15 comparing highest with lowest quartile]. However, the risk of diffuse large B-cell
lymphomas (DLBCL) tended to be lower in participants with a high intake of total vegetables (HR = 0.49, 95% CI 0.23–1.02).
Conclusion In this large prospective study, an inverse associations between fruit and vegetable consumption and risk of lymphomas overall
could not be confirmed. Associations with lymphoma subentities such as DLBCL warrant further investigation.
The work described in this article was carried out with the financial support of: Europe Against Cancer Program of the European
Commission (SANCO); Deutsche Krebshilfe, Deutsches Krebsforschungszentrum, German Federal Ministry of Education and Research;
Danish Cancer Society; Health Research Fund (FIS) of the Spanish Ministry of Health, Spanish Regional Governments of Andalucia,
Asturia, Basque Country, Murcia and Navarra; the ISCIII Network RCESP (C03/09), Spain; Cancer Research UK; Medical Research
Council, United Kingdom; Stroke Association, United Kingdom; British Heart Foundation; Department of Health, United Kingdom;
Food Standards Agency, United Kingdom; Wellcome Trust, United Kingdom; Greek Ministry of Health; Greek Ministry of Education;
Italian Association for Research on Cancer (AIRC); Italian National Research Council, Fondazione-Istituto Banco Napoli, Italy;
Compagnia di San Paolo; Dutch Ministry of Public Health, Welfare and Sports; World Cancer Research Fund; Swedish Cancer Society;
Swedish Scientific Council; Regional Government of Sk?ne, Sweden; Norwegian Cancer Society; Research Council of Norway; French
League against Cancer (LNCC); National Institute for Health and Medical Research (INSERM), France; Mutuelle Générale de l’Education
Nationale (MGEN), France; 3M Co, France; Gustave Roussy Institute (IGR), France; and General Councils of France. 相似文献
99.
The dexamethasone suppression test and CSF-5-HIAA in relation to suicidality and depression in suicide attempters. 总被引:2,自引:0,他引:2
This study tested suicidality in relation to cerebrospinal fluid (CSF) 5-hydroxyindoleacetic acid (5-HIAA) and the dexamethasone suppression test. Patients with nonsuppression of cortisol had the highest scores of the Suicide Assessment Scale (SUAS) and the Montgomery Asberg Depression Rating Scale (MADRS), respectively (P < 0.05; P < 0.01). The results persisted when analysed for covariance with CSF-5-HIAA. We have previously noted an elevated suicide risk in suicide attempters with high SUAS-scores, why a large part of nonsuppressors may be at high risk for future suicide. 相似文献
100.
Asplund A Sivertsson A Bäckvall H Ahmadian A Lundeberg J Ponten F 《Experimental dermatology》2005,14(8):593-600
Human basal cell cancer (BCC) shows unique growth characteristics, including a virtual inability to metastasize, absence of a precursor stage and lack of tumour progression. The clonal nature of BCC has long been a subject for debate because of the tumour growth pattern. Despite a morphologically multifocal appearance, genetic analysis and three-dimensional reconstructions of tumours have favoured a unicellular origin. We have utilized the X-chromosome inactivation assay in order to examine clonality in 13 cases of BCC. Four parts of each individual tumour plus isolated samples of stroma were analysed following laser-assisted microdissection. In 12/13 tumours, the epithelial component of the tumour showed a monoclonal pattern suggesting a unicellular origin. Surprisingly, one tumour showed evidence of being composed of at least two non-related monoclonal clones. This finding was supported by the analysis of the ptch and p53 gene. Clonality analysis of tumour stroma showed both mono- and polyclonal patterns. A prerequisite for this assay is that the extent of skewing is determined and compensated for in each case. Owing to the mosaic pattern of normal human epidermis, accurate coefficients are difficult to obtain; we, therefore, performed all analyses both with and without considering skewing. This study concludes that BCC are monoclonal neoplastic growths of epithelial cells, embedded in a connective tissue stroma at least in part of polyclonal origin. The study results show that what appears to be one tumour may occasionally constitute two or more independent tumours intermingled or adjacent to each other, possibly reflecting a local predisposition to malignant transformation. 相似文献