全文获取类型
收费全文 | 26132篇 |
免费 | 1770篇 |
国内免费 | 82篇 |
专业分类
耳鼻咽喉 | 222篇 |
儿科学 | 640篇 |
妇产科学 | 446篇 |
基础医学 | 3840篇 |
口腔科学 | 340篇 |
临床医学 | 2437篇 |
内科学 | 6338篇 |
皮肤病学 | 672篇 |
神经病学 | 2214篇 |
特种医学 | 791篇 |
外国民族医学 | 3篇 |
外科学 | 3787篇 |
综合类 | 270篇 |
一般理论 | 28篇 |
预防医学 | 1949篇 |
眼科学 | 489篇 |
药学 | 1613篇 |
1篇 | |
中国医学 | 56篇 |
肿瘤学 | 1848篇 |
出版年
2022年 | 134篇 |
2021年 | 335篇 |
2020年 | 226篇 |
2019年 | 361篇 |
2018年 | 422篇 |
2017年 | 288篇 |
2016年 | 354篇 |
2015年 | 414篇 |
2014年 | 625篇 |
2013年 | 947篇 |
2012年 | 1400篇 |
2011年 | 1559篇 |
2010年 | 939篇 |
2009年 | 954篇 |
2008年 | 1490篇 |
2007年 | 1653篇 |
2006年 | 1646篇 |
2005年 | 1743篇 |
2004年 | 1598篇 |
2003年 | 1527篇 |
2002年 | 1513篇 |
2001年 | 398篇 |
2000年 | 331篇 |
1999年 | 388篇 |
1998年 | 376篇 |
1997年 | 335篇 |
1996年 | 291篇 |
1995年 | 276篇 |
1994年 | 254篇 |
1993年 | 230篇 |
1992年 | 307篇 |
1991年 | 294篇 |
1990年 | 264篇 |
1989年 | 247篇 |
1988年 | 215篇 |
1987年 | 211篇 |
1986年 | 227篇 |
1985年 | 217篇 |
1984年 | 209篇 |
1983年 | 200篇 |
1982年 | 223篇 |
1981年 | 230篇 |
1980年 | 183篇 |
1979年 | 138篇 |
1978年 | 134篇 |
1977年 | 138篇 |
1976年 | 113篇 |
1975年 | 111篇 |
1974年 | 102篇 |
1973年 | 95篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
M C L'Huillier D Steschenko D Olive J L Bernard C Raybaud P Schaffer 《Revue d'épidémiologie et de santé publique》1988,36(4-5):301-308
Following the well-known European CCRs of Manchester and Turin, 2 regional CCRs have been recently created in France: in Nancy (1983) and Marseille (1984); both are population based CCRs, covering respectively 535,200 and 809,200 children (0-14 yrs). All malignant neoplasms are included, as well as brain tumours (whatever grading) and borderline malignancies. Data are collected from medical and administrative sources. Registration is active and every source is recontacted annually. The registries contact all physicians who might include children among their patients (private and hospital practice), and laboratories of pathology-cytology. The University Hospital Centers and Anti-Cancer Centers in adjacent regions, and in Paris are contacted. Death certificates for children dying of a malignant neoplasm are also sent to the registry. Data collected are as follows: name, age, sex, address, date and method of diagnosis, histological type, anatomical site, stage, treatment and sources of information. We added the data of a general cancer registry, created in Strasbourg in 1975 and covering 205,900 children. reliability of the methodology is attested by the similarity of the results obtained in other European, US and Australian CCRs. In conclusion, this type of registry is needed to organize multicentric epidemiological studies about the role of etiological factors, the survival, and the long term sequelae. 相似文献
32.
Alicia E. Ronco M. Cecilia Sobrero Gustavo D. Bulus Rossini Pablo R. Alzuet Bernard J. Dutka 《Environmental toxicology》1995,10(1):35-39
Toxicity testing of sediment samples from the Rio Santiago and its main tributaries was performed using a battery of tests that included the ECHA dipstick biocide monitor, the MetPad test, the lettuce seed germination and the root elongation test, the nematode test, spot plate test, and the SOS Chromotest. Assessment was carried out on organic extracts, pore water, and direct sediment. Results of bioassays showed toxicity sources from tributaries and canals flowing into the river and areas being degraded by insults from industrial spills. © by John Wiley & Sons, Inc. 相似文献
33.
High-Temperature Short-Time Heat Inactivation of HIV and Other Viruses in Human Blood Plasma 总被引:4,自引:0,他引:4
Stanley E. Charm Steven Landau Bolanle Williams Bernard Horowitz Alfred M. Prince and Donna Pascual 《Vox sanguinis》1992,62(1):12-20
An ultra-short-time heating system was used to process blood plasma spiked with various viruses (HIV, vesicular stomatitis virus, encephalomyocarditis virus). Virus reduction and recovery of plasma proteins were measured at various temperatures from 65 to 85 degrees C. Processing at 77 degrees C and 0.006 s resulted in a high level of virus kill, including greater than or equal to 4.4 log10 HIV, while maintaining protein structure and activity essentially intact. 相似文献
34.
Adrenocortical carcinoma in surgically treated patients: a retrospective study on 156 cases by the French Association of Endocrine Surgery. 总被引:4,自引:0,他引:4
BACKGROUND. Because of the rarity of adrenocortical carcinoma, survival rates and prognosis for patients who have undergone operation are not well known. The purpose of the French Association of Endocrine Surgery was to evaluate these factors in all patients treated during a 12-year period by its members. METHODS. One hundred fifty-six patients (95 women, 61 men) with a mean age of 47 years were included. Functional symptoms were found in 52% of patients, and hormonal studies revealed secreting tumors in 62% of cases. Ninety-four percent of the patients underwent resection of the adrenal tumor, and 20% of them had extensive resection because of invasive cancers. Complete resection was achieved in 127 patients (81%) and incomplete resection in 29 patients. Mean tumor weight was 714 gm (range, 12 to 4750 gm), and the mean diameter was 12 cm (range, 3 to 30 cm). The results of the tumor staging were stage I, eight patients (5%); stage II (local disease), 75 patients (48%); stage III (locoregional disease), 39 patients (25%); and stage IV (metastases), 34 patients (22%). RESULTS. The 5-year actuarial survival rates were 34% overall, 42% in curative group, 53% in local cancer group, 24% in regional disease group, and 27% in the reoperated group. One-year actuarial survival rate of the palliative group was 9% (median survival, 6 months). Multivariate analysis showed that better prognosis occurred in patients younger than 35 years of age (p = 0.01) and in patients with androgen-secreting tumors, precursor-secreting tumors, or nonsecreting tumors (p = 0.003). Mitotane improved the survival rate only in patients with metastases who received it after operation (vs non-mitotane-treated patients [p < 0.05]). CONCLUSIONS. In this study age, extent of disease, aspect of the surgical resection, and type of hormonal secretion influenced survival. 相似文献
35.
P J Bernard P M Som M L Urken W Lawson H F Biller 《Otolaryngology--head and neck surgery》1988,99(5):489-493
Although acute thyroiditis often has a distinctive clinical presentation, this relatively uncommon entity can occasionally be confused with other inflammatory processes. In general, the earlier the diagnosis of acute thyroiditis is established, the lower is the frequency and severity of its attendant complications. Computed tomography (CT) is an extremely useful modality in establishing the diagnosis early because it can evaluate iodine content of the thyroid gland and provides more accurate mapping than ultrasound and nuclear medicine techniques. Three patients with acute thyroiditis--two with suppuration--are presented and the CT findings and clinical aspects of this disease are reviewed. 相似文献
36.
37.
Manoussos M. Konstadoulakis MD Michael Vezeridis MD Emi Hatziyianni MD Constantine P. Karakousis MD PhD Bernard Cole PhD Kirby I. Bland MD Harold J. Wanebo MD 《Annals of surgical oncology》1998,5(3):253-260
Background: Oncogenes and other molecular tumor markers that predict tumor aggressiveness may allow individualization and optimization of surgical therapy of intermediate-thickness malignant melanoma. We examined the expression of selected markers, including the HLA-DR antigen, the heat shock protein-70 (HSP-70), and the c-myc oncogene in primary melanoma and regional nodes and related these findings to metastatic potential and survival.
Methods: Forty patients with primary melanoma (1.5–4.0 mm) were studied, all of whom had prophylactic lymph node dissection and were followed for 18 months to 7 years. The primary tissue and nodes were examined using immunohistochemical techniques for the presence of HLA-DR antigen and HSP-70 protein and the expression of the c-myc oncogene.
Results: Of 40 patients, there were 23 with lesions 1 to 2.9 mm thick and 17 with lesions 3 to 4 mm thick. Nodal metastases were present in 25 of the 40 patients who had elective node dissection. HLA-DR antibody stained the primary tumor in 10 patients (25%), but there was no correlation with survival in this group. HLA-DR antibody stained the stroma and cellular infiltrates surrounding the primary tumor in 28 of 40 patients; in this group there was a correlation of HLA-DR staining of the peritumoral stroma with improved survival overall. HLA-DR staining of the peritumoral stroma also influenced survival when patients were stratified by tumor thickness groups 1 to 2.9 mm and 3 to 4 mm and presence of nodal metastases. HSP-70 was demonstrated in the primary tumor in 25% of patients, who were also shown to have significantly improved survival when compared with those whose primary tumor did not stain with HSP-70. C-myc was expressed in the primary tumor in 25%, but showed no correlation with survival. None of these proteins correlated with or predicted the presence of nodal metastases.
Conclusion: We conclude that the use of specific molecular-oncogene markers in intermediate-thickness primary melanoma may identify patients at high risk for conventional treatment failure and reduced survival who may profit from more aggressive surgery, adjuvant therapy, or both.Presented at the 48th Annual Cancer Symposium of The Society of Surgical Oncology, Boston, Massachusetts, March 23–26, 1995. 相似文献
38.
39.
Vectorization of morpholino oligomers by the (R-Ahx-R)4 peptide allows efficient splicing correction in the absence of endosomolytic agents. 总被引:1,自引:0,他引:1
Sa?d Abes Hong M Moulton Philippe Clair Paul Prevot Derek S Youngblood Rebecca P Wu Patrick L Iversen Bernard Lebleu 《Journal of controlled release》2006,116(3):304-313
The efficient and non-toxic nuclear delivery of steric-block oligonucleotides (ON) is a prerequisite for therapeutic strategies involving splice correction or exon skipping. Cationic cell penetrating peptides (CPPs) have given rise to much interest for the intracellular delivery of biomolecules, but their efficiency in promoting cytoplasmic or nuclear delivery of oligonucleotides has been hampered by endocytic sequestration and subsequent degradation of most internalized material in endocytic compartments. In the present study, we compared the splice correction activity of three different CPPs conjugated to PMO(705), a steric-block ON targeted against the mutated splicing site of human beta-globin pre-mRNA in the HeLa pLuc705 splice correction model. In contrast to Tat48-60 (Tat) and oligoarginine (R(9)F(2)) PMO(705) conjugates, the 6-aminohexanoic-spaced oligoarginine (R-Ahx-R)(4)-PMO(705) conjugate was able to promote an efficient splice correction in the absence of endosomolytic agents. Our mechanistic investigations about its uptake mechanisms lead to the conclusion that these three vectors are internalized using the same endocytic route involving proteoglycans, but that the (R-Ahx-R)(4)-PMO(705) conjugate has the unique ability to escape from lysosomial fate and to access to the nuclear compartment. This vector, which has displays an extremely low cytotoxicity, the ability to function without chloroquine adjunction and in the presence of serum proteins. It thus offers a promising lead for the development of vectors able to enhance the delivery of therapeutic steric-block ON in clinically relevant models. 相似文献
40.
Takeshi Sakata Yongmei Wang Bernard P Halloran Hashem Z Elalieh Jay Cao Daniel D Bikle 《Journal of bone and mineral research》2004,19(3):436-446
We showed that unloading markedly diminished the effects of IGF-I to activate its signaling pathways, and the disintegrin echistatin showed a similar block in osteoprogenitor cells. Furthermore, unloading decreased alphaVbeta3 integrin expression. These results show that skeletal unloading induces resistance to IGF-I by inhibiting activation of the IGF-I signaling pathways at least in part through downregulation of integrin signaling. INTRODUCTION: We have previously reported that skeletal unloading induces resistance to insulin-like growth factor-I (IGF-I) with respect to bone formation. However, the underlying mechanism remains unclear. The aim of this study was to clarify how skeletal unloading induces resistance to the effects of IGF-I administration in vivo and in vitro with respect to bone formation. MATERIALS AND METHODS: We first determined the response of bone to IGF-I administration in vivo during skeletal unloading. We then evaluated the response of osteoprogenitor cells isolated from unloaded bones to IGF-I treatment in vitro with respect to activation of the IGF-I signaling pathways. Finally we examined the potential role of integrins in mediating the responsiveness of osteoprogenitor cells to IGF-I. RESULTS: IGF-I administration in vivo significantly increased proliferation of osteoblasts. Unloading markedly decreased proliferation and blocked the ability of IGF-I to increase proliferation. On a cellular level, IGF-I treatment in vitro stimulated the activation of its receptor, Ras, ERK1/2 (p44/42 MAPK), and Akt in cultured osteoprogenitor cells from normally loaded bones, but these effects were markedly diminished in cells from unloaded bones. These results were not caused by altered phosphatase activity or changes in receptor binding to IGF-I. Inhibition of the Ras/MAPK pathway was more impacted by unloading than that of Akt. The disintegrin echistatin (an antagonist of the alphaVbeta3 integrin) blocked the ability of IGF-I to stimulate its receptor phosphorylation and osteoblast proliferation, similar to that seen in cells from unloaded bone. Furthermore, unloading significantly decreased the mRNA levels both of alphaV and beta3 integrin subunits in osteoprogenitor cells. CONCLUSION: These results indicate that skeletal unloading induces resistance to IGF-I by inhibiting the activation of IGF-I signaling pathways, at least in part, through downregulation of integrin signaling, resulting in decreased proliferation of osteoblasts and their precursors. 相似文献