全文获取类型
收费全文 | 23172篇 |
免费 | 1470篇 |
国内免费 | 105篇 |
专业分类
耳鼻咽喉 | 181篇 |
儿科学 | 619篇 |
妇产科学 | 627篇 |
基础医学 | 3601篇 |
口腔科学 | 816篇 |
临床医学 | 2057篇 |
内科学 | 5035篇 |
皮肤病学 | 511篇 |
神经病学 | 2760篇 |
特种医学 | 611篇 |
外科学 | 2087篇 |
综合类 | 60篇 |
一般理论 | 8篇 |
预防医学 | 1587篇 |
眼科学 | 397篇 |
药学 | 1799篇 |
中国医学 | 83篇 |
肿瘤学 | 1908篇 |
出版年
2024年 | 30篇 |
2023年 | 240篇 |
2022年 | 489篇 |
2021年 | 792篇 |
2020年 | 481篇 |
2019年 | 670篇 |
2018年 | 780篇 |
2017年 | 643篇 |
2016年 | 731篇 |
2015年 | 856篇 |
2014年 | 986篇 |
2013年 | 1279篇 |
2012年 | 2019篇 |
2011年 | 2140篇 |
2010年 | 1063篇 |
2009年 | 1011篇 |
2008年 | 1583篇 |
2007年 | 1517篇 |
2006年 | 1403篇 |
2005年 | 1330篇 |
2004年 | 1173篇 |
2003年 | 1080篇 |
2002年 | 955篇 |
2001年 | 148篇 |
2000年 | 117篇 |
1999年 | 149篇 |
1998年 | 143篇 |
1997年 | 138篇 |
1996年 | 91篇 |
1995年 | 77篇 |
1994年 | 67篇 |
1993年 | 48篇 |
1992年 | 51篇 |
1991年 | 56篇 |
1990年 | 46篇 |
1989年 | 40篇 |
1988年 | 36篇 |
1987年 | 41篇 |
1986年 | 30篇 |
1985年 | 25篇 |
1984年 | 32篇 |
1983年 | 25篇 |
1982年 | 21篇 |
1981年 | 22篇 |
1980年 | 12篇 |
1979年 | 14篇 |
1978年 | 10篇 |
1977年 | 6篇 |
1975年 | 6篇 |
1973年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Caterina Proto Daniela Romualdi Rosa Maria Cento Rosario S Spada Giuseppina Di Mento Raffaele Ferri Antonio Lanzone 《Gynecological endocrinology》2006,22(4):213-218
BACKGROUND: In the central nervous system, several neuropeptides are believed to be involved in the pathophysiology of Alzheimer's disease (AD). Indeed, previous studies have documented that glucagon-like peptide 1 (GLP-1) possesses neurotropic properties and can reduce amyloid-beta peptide levels in the brain in vivo. Moreover, the concentrations of neuropeptide Y (NPY) seem to be altered in the cerebrospinal fluid of patients with AD and in subjects with major depression. Finally, among the modifications induced by aging, a dysregulation of the ghrelin-growth hormone (GH) system has been reported. METHODS: We investigated the plasma concentrations of these neuropeptides in 14 subjects with AD. Data obtained from these patients were compared with data from an age- and weight-matched healthy group. RESULTS: No significant differences were found between the two groups in relation to plasma levels of GLP-1, NPY, ghrelin and GH. Peripheral NPY concentrations were positively correlated with ghrelin levels in both groups, and with plasma GLP-1 concentration only in controls. CONCLUSION: On the basis of our results, peripheral levels of these neuropeptides seem not to serve as biochemical markers of AD. 相似文献
3.
4.
Cristina Benatti Silvia Alboni Giacomo Capone Daniela Corsini Federica Caggia Nicoletta Brunello Fabio Tascedda Joan M.C. Blom 《International journal of developmental neuroscience》2009,27(7):661-668
Protracted or recurrent pain and inflammation in the early neonatal period may cause long-lasting changes in central neural function. However, more research is necessary to better characterize the long-term behavioral sequelae of such exposure in the neonatal period. Objectives: (1) to study whether timing of postnatal exposure to persistent inflammation alters responsiveness to thermal pain in the adult animal; (2) to assess whether animals experiencing early postnatal chronic inflammation display altered anxiety related behavior; (3) to study the importance of genetic background. Newborn mice (outbred strain, CD1 and F1 hybrid strain, B6C3F1) received an injection of Complete Freund's Adjuvant (CFA) or saline on either postnatal day 1 or 14 (PND1; PND14) into the left hind paw. Pain to radiant heat and anxiety were examined in 12-week-old adult animals. Adult baseline PWL was significantly decreased in CD1 mice exposed to CFA on PND 1 and 14 as compared to their saline treated counterparts. B6C3F1 mice exposed to CFA on PND14 showed markedly reduced baseline PWL compared to the PND14 saline group. Persistent inflammation experienced by B6C3F1 mice on PND1 failed to affect baseline adult thermal responsiveness. Adult mice, CD1 and B6C3F1, displayed low anxiety traits only if they had been exposed to persistent inflammation on PND1 and not on PND14. Our research suggests a role for genetic background in modulating long-term behavioral consequences of neonatal persistent inflammation: the data support the hypothesis that pain experienced very early in life differentially affects adult behavioral and emotional responsiveness in outbred (CD1) and hybrid mice (B6C3F1). 相似文献
5.
6.
P B Schneider U Denk M Breitenbach K Richter P Schmid-Grendelmeier S Nobbe M Himly A Mari C Ebner B Simon-Nobbe 《Clinical and experimental allergy》2006,36(12):1513-1524
BACKGROUND: Alternaria alternata is one of the most important allergenic fungi worldwide. Mannitol dehydrogenase (MtDH) has previously been shown to be a major allergen of Cladosporium herbarum and cross-reactivity has been demonstrated for several fungal allergens. OBJECTIVE: The present study's objective was to clone the MtDH from an A. alternata cDNA library, express and purify the recombinant non-fusion protein and test its IgE-binding properties. Methods A cDNA library prepared from A. alternata hyphae and spores was screened for mannitol dehydrogenase by DNA hybridization with the radioactively labelled C. herbarum homologue as a probe. The resulting clone was sequenced and heterologously expressed in Escherichia coli as a recombinant non-fusion protein, which was purified to homogeneity and analysed for its IgE-binding capacity. RESULTS: The coding sequence of the full-length cDNA clone comprises 798 bp encoding a protein with a molecular mass of 28.6 kDa and a predicted pI of 5.88. Protein sequence analysis revealed an identity of 75% and a homology of 86% between the MtDHs of A. alternata and C. herbarum. The functional mannitol dehydrogenase was expressed in the E. coli strain BL21(DE3) transformed with the vector pMW172 and purified to homogeneity. The enzyme catalyses the NADPH-dependent conversion of d-fructose to d-mannitol. In IgE-ELISA and immunoblots, MtDH is recognized by 41% of A. alternata-allergic patients. In vivo immunoreactivity of the recombinant MtDH was verified by skin prick testing. Finally, inhibition-ELISA experiments confirmed cross-reactivity between the MtDHs of A. alternata and C. herbarum. CONCLUSION: Mannitol dehydrogenase (Alt a 8) represents an important new allergen of the ascomycete A. alternata that might be suitable for improving diagnostic and therapeutic procedures. 相似文献
7.
D Mari? J Velji? J Ranin B D Jankovi? 《The International journal of neuroscience》1991,59(1-3):135-142
There is a large body of evidence for the role of thymosin peptides in immunogenesis and immunity. In this paper we report on the influence of prothymosin alpha 1 (ProT-alpha 1), a hormone-like peptide derived from the calf thymus, on humoral and cellular immune reactions in the rat. Young adults received intraperitoneal injections of ProT-alpha 1 in the periods before and after immunization with cellular and soluble antigens. ProT-alpha-treatment produced a dose-dependent increase of both humoral and cell-mediated immune responses. The thymus weight increased but not that of spleen. Treatment of nonimmunized rats with this polypeptide significantly elevated the number of CD4+ and decreased the number of CD8+ cells in the peripheral blood. The results suggest a potent immunostimulatory activity of ProT-alpha 1 and imply direct action of this polypeptide on T lymphocytes. 相似文献
8.
Kazuoki Hizawa Mari Nakamori Issei Egashira Tsukane Nakahara Takayuki Matsumoto Mitsuo Iida 《Nihon Shokakibyo Gakkai zasshi》2007,104(12):1733-1737
We describe a case of 41-year-old Japanese man with Crohn's ileocolitis and cytomegalovirus infection, confirmed by histology of ileal ulcers. Although his colonoscopic and radiological features resembled those of intestinal tuberculosis, granulomas of typical Crohn's disease were evident on histology of biopsy specimens taken from the duodenum and colon. The lesions remain unchanged even after 1.5 years by oral administration of salazosulphapyridine 3g daily. 相似文献
9.
Michael Dietrich Christoph Meier Daniela Zeller Patrick Grueninger Roger Berbig Andreas Platz 《European journal of trauma and emergency surgery》2007,33(5):512-519
Abstract
Background: Primary shoulder hemiarthroplasty is an established treatment modality for complex fractures of the proximal humerus. Long-term
functional outcome is often disappointing. However, little is known about social implications particularly in the elderly.
Methods: A single-institution case series of consecutive geriatric patients (age > 70 years) treated with shoulder hemiarthroplasty
for complex fractures of the proximal humerus between 1994 and 1997 was analysed. Postoperative morbidity, long-term function,
radiological outcome and social implications were evaluated.
Results: Seventy-seven patients fulfilled the study criteria. Median age at the time of operation was 80 years (range 70–93 years).
Systemic and local postoperative complications were observed in 8% including 2 patients (3%) with revision surgery. Postoperative
mortality was 1%. Forty-eight patients (62%) were available for follow-up (median 49 months, range 25–80 months), 22 (29%)
died from causes unrelated to hemiarthroplasty before follow-up and 7 patients (9%) did not attend follow-up examination.
Median Constant-Murley score was 41 points (range 17–77 points). Long-term results concerning pain were satisfying. The Oxford
shoulder score ranged from 14 to 40 (median 30). Forty-one patients (85%) still lived in their original environment and managed
their daily life independently despite poor shoulder function. Four patients (8%) lived in a retirement home and 3 (6%) in
a nursery home. Eighty percent of our patients were still able to use public transportation, do the daily shopping and wash
their whole body by themselves.
Conclusion: Most patients managed their daily life independently despite poor shoulder function. 相似文献
10.
Angelo M. Carella Sandro Nati Paolo Carlier Daniela Pierluigi Domenico Giordano Angela Congiu Gino Santini Daniele Scarpati Salvina Barra Renzo Corvo Vito Vitale Maria R. Raffo Raffaella Cerri Marco Risso Mauro Spriano Renato Vimercati Ester Pungolino Andrea Bacigalupo Eugenio Damasio 《Leukemia & lymphoma》1991,5(1):43-47
Forty consecutive adult patients under the age of 50 with acute non-lymphoblastic leukemia (ANLL) in first complete remission, underwent autologous bone marrow transplantation (ABMT) between March 1984 and April 1990. The conditioning regimen employed included cyclophosphamide and total body irradiation, followed by the administration of unpurged ABMT. The median time from diagnosis to transplant was 7 months (3-15 months), and the median time from complete remission to ABMT was 4 months (range 3-9 months). Twenty-two (51%) patients remain in complete remission 6-81 months (median 24 months) after ABMT.
The causes of death were, recurrent leukemia (11 patients), parenchymal toxicities such as acute respiratory distress syndrome and veno-occlusive disease (3 patients), hemorrhage (2 patients) and infection (2 patients). Eleven patients relapsed after 3-12 months (median 5 months). This study has produced survival data comparable to those of other institutions employing TBI for either allo or autotransplants. 相似文献
The causes of death were, recurrent leukemia (11 patients), parenchymal toxicities such as acute respiratory distress syndrome and veno-occlusive disease (3 patients), hemorrhage (2 patients) and infection (2 patients). Eleven patients relapsed after 3-12 months (median 5 months). This study has produced survival data comparable to those of other institutions employing TBI for either allo or autotransplants. 相似文献