全文获取类型
收费全文 | 1723篇 |
免费 | 49篇 |
国内免费 | 75篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 111篇 |
妇产科学 | 20篇 |
基础医学 | 165篇 |
口腔科学 | 15篇 |
临床医学 | 182篇 |
内科学 | 432篇 |
皮肤病学 | 49篇 |
神经病学 | 77篇 |
特种医学 | 329篇 |
外科学 | 116篇 |
综合类 | 28篇 |
预防医学 | 63篇 |
眼科学 | 34篇 |
药学 | 109篇 |
中国医学 | 5篇 |
肿瘤学 | 110篇 |
出版年
2020年 | 12篇 |
2018年 | 16篇 |
2016年 | 11篇 |
2015年 | 20篇 |
2014年 | 27篇 |
2013年 | 35篇 |
2012年 | 40篇 |
2011年 | 52篇 |
2010年 | 47篇 |
2009年 | 67篇 |
2008年 | 38篇 |
2007年 | 71篇 |
2006年 | 38篇 |
2005年 | 48篇 |
2004年 | 27篇 |
2003年 | 33篇 |
2002年 | 27篇 |
2001年 | 32篇 |
2000年 | 50篇 |
1999年 | 26篇 |
1998年 | 90篇 |
1997年 | 79篇 |
1996年 | 71篇 |
1995年 | 56篇 |
1994年 | 48篇 |
1993年 | 51篇 |
1992年 | 34篇 |
1991年 | 34篇 |
1990年 | 34篇 |
1989年 | 50篇 |
1988年 | 59篇 |
1987年 | 43篇 |
1986年 | 37篇 |
1985年 | 39篇 |
1984年 | 30篇 |
1983年 | 30篇 |
1982年 | 22篇 |
1981年 | 17篇 |
1980年 | 23篇 |
1979年 | 20篇 |
1978年 | 16篇 |
1977年 | 29篇 |
1976年 | 16篇 |
1975年 | 22篇 |
1974年 | 22篇 |
1973年 | 23篇 |
1972年 | 25篇 |
1971年 | 15篇 |
1970年 | 13篇 |
1968年 | 11篇 |
排序方式: 共有1847条查询结果,搜索用时 15 毫秒
131.
Benson C White J De Bono J O'Donnell A Raynaud F Cruickshank C McGrath H Walton M Workman P Kaye S Cassidy J Gianella-Borradori A Judson I Twelves C 《British journal of cancer》2007,96(1):29-37
Seliciclib (CYC202; R-roscovitine) is the first selective, orally bioavailable inhibitor of cyclin-dependent kinases 1, 2, 7 and 9 to enter clinical trial. Preclinical studies showed antitumour activity in a broad range of human tumour xenografts. A phase I trial was performed with a 7-day b.i.d. p.o. schedule. Twenty-one patients (median age 62 years, range: 39-73 years) were treated with doses of 100, 200 and 800 b.i.d. Dose-limiting toxicities were seen at 800 mg b.i.d.; grade 3 fatigue, grade 3 skin rash, grade 3 hyponatraemia and grade 4 hypokalaemia. Other toxicities included reversible raised creatinine (grade 2), reversible grade 3 abnormal liver function and grade 2 emesis. An 800 mg portion was investigated further in 12 patients, three of whom had MAG3 renograms. One patient with a rapid increase in creatinine on day 3 had a reversible fall in renal perfusion, with full recovery by day 14, and no changes suggestive of renal tubular damage. Further dose escalation was precluded by hypokalaemia. Seliciclib reached peak plasma concentrations between 1 and 4 h and elimination half-life was 2-5 h. Inhibition of retinoblastoma protein phosphorylation was not demonstrated in peripheral blood mononuclear cells. No objective tumour responses were noted, but disease stabilisation was recorded in eight patients; this lasted for a total of six courses (18 weeks) in a patient with ovarian cancer. 相似文献
132.
Pharmacologic characterization of a potent inhibitor of class I phosphatidylinositide 3-kinases 总被引:11,自引:0,他引:11
Raynaud FI Eccles S Clarke PA Hayes A Nutley B Alix S Henley A Di-Stefano F Ahmad Z Guillard S Bjerke LM Kelland L Valenti M Patterson L Gowan S de Haven Brandon A Hayakawa M Kaizawa H Koizumi T Ohishi T Patel S Saghir N Parker P Waterfield M Workman P 《Cancer research》2007,67(12):5840-5850
Extensive evidence implicates activation of the lipid phosphatidylinositide 3-kinase (PI3K) pathway in the genesis and progression of various human cancers. PI3K inhibitors thus have considerable potential as molecular cancer therapeutics. Here, we detail the pharmacologic properties of a prototype of a new series of inhibitors of class I PI3K. PI103 is a potent inhibitor with low IC50 values against recombinant PI3K isoforms p110alpha (2 nmol/L), p110beta (3 nmol/L), p110delta (3 nmol/L), and p110gamma (15 nmol/L). PI103 also inhibited TORC1 by 83.9% at 0.5 micromol/L and exhibited an IC50 of 14 nmol/L against DNA-PK. A high degree of selectivity for the PI3K family was shown by the lack of activity of PI103 in a panel of 70 protein kinases. PI103 potently inhibited proliferation and invasion of a wide variety of human cancer cells in vitro and showed biomarker modulation consistent with inhibition of PI3K signaling. PI103 was extensively metabolized, but distributed rapidly to tissues and tumors. This resulted in tumor growth delay in eight different human cancer xenograft models with various PI3K pathway abnormalities. Decreased phosphorylation of AKT was observed in U87MG gliomas, consistent with drug levels achieved. We also showed inhibition of invasion in orthotopic breast and ovarian cancer xenograft models and obtained evidence that PI103 has antiangiogenic potential. Despite its rapid in vivo metabolism, PI103 is a valuable tool compound for exploring the biological function of class I PI3K and importantly represents a lead for further optimization of this novel class of targeted molecular cancer therapeutic. 相似文献
133.
AB Rossi JJ Leyden AS Pappert A Ramaswamy A Nkengne R Ramaswamy M Nighland 《Journal of the European Academy of Dermatology and Venereology》2011,25(4):398-402
Background Post‐inflammatory hyperpigmentation (PIH) is a common occurrence in patients with acne vulgaris, particularly in those with skin of colour. Aims A previous study has demonstrated the benefit of tretinoin (retinoic acid) in the treatment of PIH; however, there is currently no standard protocol to evaluate change in PIH following treatment. Based on these findings, we performed a pilot, exploratory, blinded, intraindividual‐controlled methodology study that consisted of a photographic assessment protocol with facial mapping. Materials and methods The study was based on a secondary analysis of a phase 4, community‐based trial of 544 acne patients who were treated with tretinoin gel microsphere 0.04% or 0.1%. Only patients with Fitzpatrick types III–V (skin of colour) were included in the study; subjects with Fitzpatrick skin type VI were excluded because the photographic assessment did not allow for proper evaluation. Results Despite the small number of subjects evaluated (n = 25), the results revealed consistent assessment of improvement in PIH between two independent graders (weighted κ = 0.84). Conclusion Further study with a larger population is recommended to validate the accuracy of this method. 相似文献
134.
A Levy Bencheton JM Berenger P Del Giudice P Delaunay F Pages JJ Morand 《Journal of the European Academy of Dermatology and Venereology》2011,25(5):599-602
Background Bedbugs (Cimex lectularius) have been feeding on sleeping human beings since prehistory. In Europe, bed bugs were common and endemic until World War II when improved body and home hygiene, and widespread use of insecticides led to almost complete eradication. Current evidence indicates that bedbugs are making a comeback in Europe, USA, Canada and Australia. In our practice in Southern France, we observed several cases within a period of only 1 year. Objectives Based on this experience, we conducted an epidemiological study to evaluate the status of bedbugs in France. Methods During summer 2009, we mailed a short questionnaire to all hospital professors in the CEDEF (Collège des Enseignants de Dermatologie de France) asking four questions: number of suspected diagnosis of bedbugs in the year 2009, and number of certain positive diagnosis, difficulties in treatment, use of a pest control professional for treatment, and finally personal opinion on actual incidence of bedbugs, compared with past years. Results Of the 84 questionnaires sent, there were only 26 responses despite two reminders. The responses were predominantly southern France, probably as a result of intensive immigration and increased travel and trade. Difficulties encountered during diagnosis and treatment are also mentioned. Utilizing the services of entomological experts and pest control professionals is essential. Conclusions France has the same experience regarding the resurgence of bedbugs as several European countries, USA, Canada and Australia, especially the southern regions. This emerging health problem has to be known by dermatologists. A national programme has been launched in France to assess actual incidence and study C. lectularius‐ related diseases. 相似文献
135.
L. Le Saché‐de Peufeilhoux E. Raynaud A. Bouchardeau S. Fraitag C. Bodemer 《Journal of the European Academy of Dermatology and Venereology》2014,28(3):370-373
Background Hailey‐Hailey disease (HHD) or familial benign chronic pemphigus is a rare autosomal dominant inherited skin disorder, characterized by flaccid vesicles and erosions on the intertriginous areas. Current treatments are not particularly effective. We report 6 cases dramatically improving with doxycycline. Case reports 6 patients, aged from 33 to 77 years old, presented with a variable 4 to 40 year history of severe treatment‐resistant HHD. All 6 patients were then treated successfully with doxycycline 100 mg per day for at least 3 months. Discussion An improvement was observed in all 6 patients from 1 week to 3 months after the beginning of treatment. Relapses were observed after various periods. Maintenance half‐dose therapy seemed to be beneficial in patients experiencing recurrence. Only one patient developed gastro‐intestinal intolerance. No other side effects were reported. Currently, 2 patients have improved and present a decreased number of exacerbations, 2 others are in complete remission after more than 5 years of follow‐up. Treatment efficiency is difficult to evaluate in HHD as it is a rare condition. No controlled studies have been published. Local treatments may improve inflammation but do not treat the underlying cause, targeted systemic therapies exist but there is little evidence supporting their use, physical treatments are cumbersome. Besides their antibiotic potential, tetracycline antibiotics also have anti‐inflammatory properties and anticollagenase activity via inhibition of matrix metalloproteinases. Conclusions Doxycycline appears to be an interesting therapeutic option in Hailey‐Hailey disease. 相似文献
136.
137.
Anne-Laure Adra Marie-Gabrielle Vigue Fabienne Dalla Vale Lydia Ichay Pierre Raynaud Aude Mariani Denis Morin 《Pediatric nephrology (Berlin, Germany)》2010,25(9):1765-1769
Mycoplasma pneumoniae-associated nephritis has been reported in children with various pathological findings. It nevertheless remains an uncommon
disease and, within this clinical context, endo-and extracapillary glomerulonephritis in a child has never been described.
We report here a case of a 3-year-old girl diagnosed with severe crescentic glomerulonephritis associated with M. pneumoniae infection who presented with nephrotic syndrome and impaired renal function. The serum C3 complement level was initially
low but returned to normal after 1 month. Two courses of three methylprednisolone pulses were administered in association
with plasmapheresis and, secondarily, mycophenolate mophetil. This treatment regimen led to disease remission and a favorable
renal outcome at the 6-month follow-up. However, the treatment guidelines in this situation remain debatable. 相似文献
138.
Crist WM; Shuster JJ; Falletta J; Pullen DJ; Berard CW; Vietti TJ; Alvarado CS; Roper MA; Prasthofer E; Grossi CE 《Blood》1988,72(6):1891-1897
The immunophenotypes of lymphoblasts from children with newly diagnosed T-cell acute lymphoid leukemia (T-ALL, n = 101) or T-cell non-Hodgkin lymphoma (T-NHL, n = 31) were analyzed to correlate stage of thymocyte differentiation with clinical features and outcome. The 67 boys and 34 girls with T-ALL were 1 month to 18 years old (median, 8 years) with leukocyte counts ranging from 2 to 810 x 10(9)/L (median, 55 x 10(9)/L). Eighteen of these patients were black, and 70 had a mediastinal mass. Twenty-six boys and five girls with a median age of 9 years (range, 1 to 20 years) had T-NHL. Seven of these patients were black, and 24 had a mediastinal mass. The distributions of thymocyte developmental stages (early [CD7+], intermediate [CD1+ and/or CD4+ and/or CD8+], and mature [CD3+]) in cases of T-ALL and T-NHL were significantly different: 34%, 43%, and 23% v 6%, 62%, and 32% (P = .02). A comparison of the patients' clinical features according to the maturational stage of thymocytes failed to disclose significant differences in the majority of characteristics studied. However, patients with mature-stage T-NHL, with or without the addition of subjects with mature-stage T-ALL, were less likely to have a mediastinal mass (P = .02 for both comparisons). Those with intermediate-stage T-cell malignancy (T-ALL and T-NHL combined) were the subgroup most likely to have a mediastinal mass (P = .01). Response to remission induction therapy was significantly worse in the T-ALL subgroup with an early-stage phenotype: a failure rate of 21% v 0% and 6% for the two more differentiated phenotypic subgroups (P = .007). Event-free survival was not affected by thymocyte maturational stage in cases of either T-ALL or T-NHL. Despite evidence of clinical heterogeneity among the maturational stages of T-cell malignancies in children, these developmental subdivisions do not appear to be critical determinants of outcome once remission is achieved. We conclude that such phenotypes need not be included in the stratification plans for clinical trials using common induction treatment. 相似文献
139.
Adenylate cyclase and guanylate cyclase activity in normal and leukemic human lymphocytes 总被引:1,自引:0,他引:1
Adenylate cyclase (AC) and guanylate cyclase (GC) activities were studied in normal B-enriched and T-enriched lymphocytes, in lymphocytes of children with acute lymphocytic leukemia (ALL), and in lymphocytes of adults with chronic lymphocytic leukemia (CLL). AC activity was greater in normal B than T lymphocytes (215 pmole/min/mg protein versus 80 pmole in the membrane-enriched fraction) and i both increased greatly after stimulation with isoproterenol and more so with prostaglandins E and F2 alpha. In leukemic lymphocytes, AC showed depressed activity (20 pmole in ALL cells and 55 pmole in CLL cells) and was less sensitive to hormonal stimulation: this loss of sensitivity occurred to a greater extent in ALL than in CLL lymphocytes. GC activity was greater in normal T than B cells (in membrane-enriched fraction: 10.2 pmole versus 5.3 pmole). It increased little with isoproterenol and prostaglandins stimulation, and much more with sodium azide and dehydroascorbic acid stimulation. GC activity was increased in both types of leukemic lymphocytes (23 pmole for ALL cells and 18 pmole for CLL cells) and was insensitive to stimulation. Possible derangement of cyclase and cyclic nucleotide regulation in leukemic cells is suggested. 相似文献
140.
MB Vincent JJ Freitas de Carvalho the Brazilian Headache Care Cooperative Group 《Cephalalgia : an international journal of headache》1999,19(5):520-524
Headaches are common disorders usually examined by nonneurologists. In order to assess how primary headache patients (IHS groups 1, 2, and 3) are generally managed by nonspecialists, 414 patients were asked about their previous headache care. Correct diagnosis had previously been made in only 44.9%, 6.7%, and 26.7% of the migraine, tension-type headache, and cluster headache patients, respectively. The patients underwent 501 investigative procedures motivated by the headache, averaging 1.21 examinations per patient, mostly EEGs. Preventive treatment was largely overlooked irrespective of the headache type. It is concluded that scientific improvements in headache care may be ineffective unless educational programs improve headache knowledge in general. 相似文献