全文获取类型
收费全文 | 12108篇 |
免费 | 885篇 |
国内免费 | 25篇 |
专业分类
耳鼻咽喉 | 174篇 |
儿科学 | 370篇 |
妇产科学 | 237篇 |
基础医学 | 1567篇 |
口腔科学 | 356篇 |
临床医学 | 1140篇 |
内科学 | 2484篇 |
皮肤病学 | 114篇 |
神经病学 | 1289篇 |
特种医学 | 526篇 |
外国民族医学 | 1篇 |
外科学 | 1712篇 |
综合类 | 170篇 |
一般理论 | 2篇 |
预防医学 | 1223篇 |
眼科学 | 225篇 |
药学 | 786篇 |
中国医学 | 3篇 |
肿瘤学 | 639篇 |
出版年
2022年 | 75篇 |
2021年 | 150篇 |
2020年 | 108篇 |
2019年 | 180篇 |
2018年 | 217篇 |
2017年 | 148篇 |
2016年 | 170篇 |
2015年 | 206篇 |
2014年 | 268篇 |
2013年 | 446篇 |
2012年 | 660篇 |
2011年 | 743篇 |
2010年 | 424篇 |
2009年 | 377篇 |
2008年 | 628篇 |
2007年 | 615篇 |
2006年 | 692篇 |
2005年 | 636篇 |
2004年 | 571篇 |
2003年 | 513篇 |
2002年 | 539篇 |
2001年 | 360篇 |
2000年 | 344篇 |
1999年 | 261篇 |
1998年 | 141篇 |
1997年 | 109篇 |
1996年 | 87篇 |
1995年 | 79篇 |
1994年 | 89篇 |
1993年 | 96篇 |
1992年 | 191篇 |
1991年 | 210篇 |
1990年 | 213篇 |
1989年 | 184篇 |
1988年 | 143篇 |
1987年 | 163篇 |
1986年 | 152篇 |
1985年 | 185篇 |
1984年 | 134篇 |
1983年 | 129篇 |
1982年 | 65篇 |
1981年 | 80篇 |
1980年 | 73篇 |
1979年 | 124篇 |
1978年 | 85篇 |
1977年 | 62篇 |
1975年 | 64篇 |
1974年 | 73篇 |
1973年 | 61篇 |
1972年 | 70篇 |
排序方式: 共有10000条查询结果,搜索用时 11 毫秒
71.
T lymphocytes and activated eosinophils in airway mucosa in fatal asthma and cystic fibrosis. 总被引:14,自引:0,他引:14
M Azzawi P W Johnston S Majumdar A B Kay P K Jeffery 《The American review of respiratory disease》1992,145(6):1477-1482
With the use of monoclonal antibodies (mAb) and immunohistology, the numbers of phenotypically distinct cells infiltrating lung tissue from 15 postmortem (PM) cases of fatal asthma were quantified and compared with 6 cases of cystic fibrosis (CF) (three postmortem, three transplant) and 10 nonasthmatic cases of sudden death matched for age and sex. Tissue eosinophilia was significantly greater (p less than 0.001) in the fatal asthma group than in the CF or sudden death controls. In asthma, approximately 40% of the eosinophilic infiltrate was EG2 positive (an indication of eosinophil activation and secretion of eosinophil cationic protein). The numbers of eosinophils and EG2 positive cells were significantly elevated in the subjects with acute severe asthma who had had a duration of terminal illness exceeding, as compared with less than, 24 h (p less than 0.05). When compared with the sudden death controls, there were increases in the numbers of Dako L C positive cells (i.e., CD45 positive "total leukocytes") in both fatal asthma and CF (p less than 0.01 and 0.05, respectively). The mean number of MT-1 positive (T) cells in the asthma and CF groups was approximately twice that of the control (p less than 0.05 and 0.01, respectively). The mean number of MB2 positive (B) cells was similar for both the asthma and sudden death control groups but was significantly increased in CF (p less than 0.05). The average T:B cell ratios were 6:1, 1:1, and 2:1 in the fatal asthma, CF, and control groups, respectively. The results support a role for the T lymphocyte in the pathogenesis of fatal asthma and CF.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
72.
73.
Heinz Schurawitzki M.D. Paul C. Hajek Josef Kramer Florian Grabenwöger Walter Klepetko Anton Moritz 《Cardiovascular and interventional radiology》1989,12(1):10-13
In a radiologic search for embolized leaflets of Edwards-Duromedics bileaflet valves in 2 patients, the embolized fragments were localized in the iliac vessels using computed tomography. Sonography was successful in one case and standard X-ray films of the abdomen were negative in both cases.In vitro investigations with Björk-Shiley and Edwards-Duromedics leaflets suggested that standard X-ray films of the abdomen and pelvis should be considered as the first investigational technique. If negative, computed tomography of the lower abdomen should be done. 相似文献
74.
J. L. Bruins A. A. B. Lycklama à Nijeholt J. A. M. Beekhuis-Brussee A. E. J. L. Kramer J. H. J. M. van Krieken 《World journal of urology》1989,7(1):22-26
Summary Patients in whom an abnormal rectal examination leads to the suspicion of prostatic carcinoma underwent both fine-needle aspiration biopsy for cytological evaluation and core biopsy for histological evaluation. The data from 826 paired observations, collected over a 7-year period are compared. The material available was inadequate for cytology in 94 cases (11.4%) and for histology in 18 cases (2.2%). Cytology results were classified as positive (Papanicolaou 4–5) or negative (1–3) for carcinoma, and histology results as indicative of malignancy or no proven malignancy. Initially the cytology results correlated with the histology results in 84.4%, with a sensitivity of 89.7% and a specificity of 81.5%. After revision of all discrepant slides these figures increased to 88.6%, 92.8% and 86.4%, respectively. Clinical or histological follow up of patients with discrepant results was conclusive in 36 patients, giving evidence of malignancy in 24 patients and of benign pathology in 12. In this discrepancy group, comparison of both cytological and histological results with these clinical data gave a sensitivity for cytology of 63% as against 37% for histology, and a specificity for cytology of 17%, as against 83% for histology. It is concluded that fine-needle aspiration biopsy cytology is a reliable, simple and sensitive technique that can be used to confirm a suspicion of prostatic carcinoma. 相似文献
75.
Summary In the present investigation, administration of a single i.p. dose of the anticancer drug merbarone [5-(N-phenylcarboxamido)-2-thiobarbituric acid] produced an acute and reversible decrease in renal function in female but not male Fischer 344 rats. The renal lesion in female rats was biochemically characterized as a decrease inp-aminohippuric acid accumulation by renal slices along with polyuria, glucosuria, proteinuria, and enzymuria. These functional changes were accompanied by histopathologic changes of focal tubular necrosis that was confined to the deep cortex and outer stripe of the outer medulla. The changes in these parameters were dose-dependent and were observed at doses as low as 0.2×MELD10 (12 mg/kg). This low merbarone dose increased urinary glucose and protein excretion by 26- and 9-fold, respectively, in the initial 16-h urine collection in female rats. This increase was accompanied by a 2- to 15-fold increase in the excretion ofN-acetyl--d-glucosaminidase (NAG), -glutamyl transpeptidase (-GTP), and lactate dehydrogenase (LDH) activities. No significant changes in renal function were observed in male rats apart from mild enzymuria after a high dose of merbarone (36 mg/kg). The drug did not increase urea nitrogen levels in male or female rats, reflecting the focal nature of this tubular lesion. Merbarone produced small elevations in serum transaminase activities [i. e., glutamic-oxalacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT)] at doses that produced marked alterations in renal function in female rats, suggesting only mild hepatotoxicity. The present study establishes the kidney as a possible dose-limiting target organ for merbarone toxicity. 相似文献
76.
C N Coleman L Noll A E Howes J R Harris J Zakar R A Kramer 《International journal of radiation oncology, biology, physics》1989,16(4):1085-1087
To exploit both the oxygen-mimetic and "pre-incubation" or continuous exposure effects of the 2-nitroimidazole radiosensitizers, we are conducting a Phase I trial of continuous infusion SR 2508 for patients receiving brachytherapy. Following the administration of a loading dose of 2 g/m2, SR 2508 is administered by continuous infusion for 48 hr. Twenty-one patients have completed treatment. The initial total dose was 8 g/m2 with patients currently receiving 15 g/m2. No toxicity has been observed. At the higher doses the steady-state plasma concentrations have been between 50 and 70 micrograms/ml. It is not yet known whether or not hypoxic sensitizers will be of benefit clinically, and if so, when during a course of treatment is the optimal time to use them. Given the lack of toxicity and plasma concentrations achievable with continuous infusion, future studies will be conducted using SR 2508 during both the external beam and brachytherapy aspects of treatment. 相似文献
77.
Preservation and redirection of HPV16E7-specific T cell receptors for immunotherapy of cervical cancer 总被引:6,自引:0,他引:6
Scholten KB Schreurs MW Ruizendaal JJ Kueter EW Kramer D Veenbergen S Meijer CJ Hooijberg E 《Clinical immunology (Orlando, Fla.)》2005,114(2):119-129
Human papilloma virus (HPV) type 16 infections of the genital tract are associated with the development of cervical cancer (CxCa) in women. HPV16-derived oncoproteins E6 and E7 are expressed constitutively in these lesions and might therefore be attractive candidates for T-cell-mediated adoptive immunotherapy. However, the low precursor frequency of HPV16E7-specific T cells in patients and healthy donors hampers routine isolation of these cells for adoptive transfer. To overcome this problem, we have isolated T cell receptor (TCR) genes from four different HPV16E7-specific healthy donor and patient-derived human cytotoxic T lymphocyte (CTL) clones. We examined whether genetic engineering of peripheral blood-derived CD8+ T cells in order to express HPV16E711-20-specific TCRs is feasible for adoptive transfer purposes. Reporter cells (Jurkat/MA) carrying a transgenic TCR were shown to bind relevant but not irrelevant tetramers. Moreover, these TCR-transgenic Jurkat/MA cells showed reactivity towards relevant target cells, indicating proper functional activity of the TCRs isolated from already available T cell clones. We next introduced an HPV16E711-20-specific TCR into blood-derived, CD8+ recipient T cells. Transgenic CTL clones stained positive for tetramers presenting the relevant HPV16E711-20 epitope and biological activity of the TCR in transduced CTL was confirmed by lytic activity and by interferon (IFN)-gamma secretion upon antigen-specific stimulation. Importantly, we show recognition of the endogenously processed and HLA-A2 presented HPV16E711-20 CTL epitope by A9-TCR-transgenic T cells. Collectively, our data indicate that HPV16E7 TCR gene transfer is feasible as an alternative strategy to generate human HPV16E7-specific T cells for the treatment of patients suffering from cervical cancer and other HPV16-induced malignancies. 相似文献
78.
Füst G Arason GJ Kramer J Szalai C Duba J Yang Y Chung EK Zhou B Blanchong CA Lokki ML Bödvarsson S Prohászka Z Karádi I Vatay A Kovács M Romics L Thorgeirsson G Yu CY 《International immunology》2004,16(10):1507-1514
The genetic basis for addiction to tobacco smoking--particularly that of the perception of olfactory stimuli that may be important in reinforcing smoking addiction--is largely unknown. A cluster of genes for olfactory receptors is in close proximity to the MHC region on chromosome 6. Polymorphisms of MHC class III genes (RCCX modules, TNFA promoter polymorphisms) were determined in 101 healthy subjects and 232 coronary artery disease (CAD) patients from Hungary with defined tobacco smoking habits. A highly significant association between ever smoking (past + current smokers) and a specific MHC haplotype was observed (odds ratios = 2.14-4.13; P-values = 0.012 to <0.001). This haplotype is characterized by the presence of C4A null alleles and a solitary short C4B gene linked to the TNF2 allele of the promoter for TNFA gene. This haplotype occurred more frequently in the ever smokers than in the never smokers [odds ratio: 4.97 (1.96-12.62); P = 0.001], and such associations were stronger in women (odds ratio = 13.6) than in men (odds ratio = 2.79). An independent study of complement C4 protein polymorphism and smoking habits in Icelandic subjects (n = 351) yielded similar and confirmative results. Considering the documented link between olfactory stimuli and smoking in females, and the presence of a cluster of odorant receptor genes close to the MHC class I region, our findings implicate a potential role of the MHC-linked olfactory receptor genes in the initiation of smoking. 相似文献
79.
John S Thompson Claire Pomeroy Richard J Kryscio Stephen A Brown Donna Reece Rita Kramer Dianna S Howard Gary VanZant Suzanne Humphries Gordon Phillips 《Biology of blood and marrow transplantation》2004,10(12):858-866
To reduce the toxicity of traditional conditioning regimens for allogeneic stem cell transplantation (allo-SCT), we used single-agent chemotherapy conditioning with either busulfan (total cumulative dose, 16 mg/kg) or melphalan (200 to 240 mg/m 2 ), followed by the anti-T cell-specific monoclonal antibody T10B9 (MEDI-500) daily for 3 days. T cell-replete SCT was performed from HLA-identical sibling donors. Acute graft-versus-host disease (aGVHD) prophylaxis consisted of 7 additional days of T10B9 and delayed onset of cyclosporine (ie, on day +4 or +5). Twenty-six high-risk hematologic malignancy patients were entered onto this study. All 24 patients who survived longer than 8 days engrafted, although 1 patient experienced late graft failure. Deaths occurred in 21 of 26 patients because of infection (n = 7), progression/recurrence of primary disease (n = 6), aGVHD (n = 4), regimen-related toxicity (n = 1), and other causes (n = 3). Five of these patients are enjoying disease-free survival with a median survival of 1193 days after allo-SCT. The conditioning regimen induced modulation of surface expression of CD3 (but not CD4 or CD8) and was associated with decreasing tumor necrosis factor-alpha (but not interleukin-6) serum levels. In conclusion, single-agent chemotherapy conditioning with T10B9 produced durable engraftment and long-term survival in some patients who would not have qualified for a traditional allo-SCT. 相似文献
80.
Yves de Roten Mlanie Fischer Martin Drapeau Vronique Beretta Ueli Kramer Nathalie Favre Jean‐Nicolas Despland 《Clinical psychology & psychotherapy》2004,11(5):324-331
Early therapeutic alliance is usually measured by the rating of a single session (between the third and the fifth sessions). However, there is a strong argument in favor of viewing early alliance as a developing process. This study examined the relationship between patient's rating of the helping alliance (HAq) at each session and therapy outcome. This comparison was repeated using patterns of alliance over the course of treatment. Patterns of therapeutic alliance development were detected by clustering ratings of a sample of N = 70 outpatients across four sessions of very brief psychotherapeutic intervention. Cluster analysis revealed two main patterns (shapes) of alliance development: (i) stable alliance, and (ii) linear growth pattern. These patterns are more predictive of symptom improvement and social adjustment than single ratings, whereas single ratings measuring the strength of alliance are more correlated with patient's satisfaction. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献