全文获取类型
收费全文 | 546篇 |
免费 | 46篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 19篇 |
妇产科学 | 8篇 |
基础医学 | 58篇 |
口腔科学 | 13篇 |
临床医学 | 44篇 |
内科学 | 123篇 |
皮肤病学 | 22篇 |
神经病学 | 29篇 |
特种医学 | 57篇 |
外科学 | 57篇 |
综合类 | 12篇 |
预防医学 | 39篇 |
眼科学 | 10篇 |
药学 | 40篇 |
肿瘤学 | 62篇 |
出版年
2023年 | 3篇 |
2022年 | 4篇 |
2021年 | 9篇 |
2020年 | 2篇 |
2019年 | 3篇 |
2018年 | 9篇 |
2017年 | 5篇 |
2016年 | 13篇 |
2015年 | 7篇 |
2014年 | 21篇 |
2013年 | 26篇 |
2012年 | 27篇 |
2011年 | 25篇 |
2010年 | 16篇 |
2009年 | 37篇 |
2008年 | 31篇 |
2007年 | 31篇 |
2006年 | 21篇 |
2005年 | 18篇 |
2004年 | 22篇 |
2003年 | 22篇 |
2002年 | 28篇 |
2001年 | 21篇 |
2000年 | 17篇 |
1999年 | 8篇 |
1998年 | 17篇 |
1997年 | 19篇 |
1996年 | 17篇 |
1995年 | 13篇 |
1994年 | 11篇 |
1993年 | 8篇 |
1992年 | 12篇 |
1991年 | 6篇 |
1990年 | 5篇 |
1989年 | 7篇 |
1988年 | 9篇 |
1987年 | 6篇 |
1986年 | 7篇 |
1985年 | 8篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1981年 | 3篇 |
1980年 | 4篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1973年 | 2篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有597条查询结果,搜索用时 15 毫秒
61.
Erratum to: World J Surg DOI 10.1007/s00268-007-9236-7 The original version of this article, published online on September 25, 2007 and in print in the November 2007 issue (vol
31/no 11, pp 2138–2143), did not include the full list of authors’ names. The correct list of authors and their affiliations
are shown below.
The article is reprinted in its entirety.
Abstract
Background Previous studies have failed to identify predictors of early readmission after major intestinal operations. The objectives
of this study were to determine readmission rates, outcomes, and predictors of readmission for patients undergoing laparoscopic
colon and rectal operations.
Methods Patients readmitted (PR) to the hospital within 30 days of discharge after laparoscopic colon and rectal operations were identified
from a prospectively maintained database. The PR group was compared with patients that were not readmitted (NR). Outcomes
and variables related to readmission were evaluated.
Results There were 820 consecutive elective laparoscopic colon and rectal operations performed over a 5-year period, with adequate
follow-up data for 787 cases. Seventy-nine (10%) patients were readmitted. There was no difference in the age, sex, surgeon,
or type of operation between the PR and NR groups. The most common causes for readmission were bowel obstruction (19%), ileus
(18%), intra-abdominal abscess (14%), and anastomotic leak (9%). Overall mean (median) length of stay (LOS) for the index
admission was 3.7 ± 4.3 (3.0) days. Patients in the PR group had a trend toward a longer index admission LOS than the NR group
(5.4 ± 8.8 [3.0] versus 3.5 ± 3.3 [3.0], p = 0.068). Univariate analysis demonstrated that patients with inflammatory bowel disease, pulmonary comorbidities, and steroid
use were more likely to be readmitted. Multivariate analysis confirmed that inflammatory bowel disease and pulmonary comorbidity
are independent risk factors for readmission.
Conclusions Early readmission after laparoscopic colon and rectal operations is not associated with early discharge. Identification of
specific patient characteristics indicating risk for early readmission may allow for selective changes in perioperative care
or discharge criteria to avoid unexpected readmission.
The online version of the original article can be found under doi:. 相似文献
62.
Germano Silvia Borsetti Marco Gangemi Ezio Nicola Clemente Alessandra Rivarossa Filippo Cavalieri Enrico Patanè Luca Merlino Giorgio 《Oral and maxillofacial surgery》2023,27(2):283-288
Oral and Maxillofacial Surgery - The radial forearm free flap (RFFF) remains a workhorse in microsurgical reconstruction. Its failure is primarily due to problems with venous drainage; for this... 相似文献
63.
Vitamin D intake is inversely associated with rheumatoid arthritis: results from the Iowa Women's Health Study 总被引:5,自引:0,他引:5
Merlino LA Curtis J Mikuls TR Cerhan JR Criswell LA Saag KG;Iowa Women's Health Study 《Arthritis and rheumatism》2004,50(1):72-77
OBJECTIVE: Vitamin D is a potent regulator of calcium homeostasis and may have immunomodulatory effects. The influence of vitamin D on human autoimmune disease has not been well defined. The purpose of this study was to evaluate the association of dietary and supplemental vitamin D intake with rheumatoid arthritis (RA) incidence. METHODS: We analyzed data from a prospective cohort study of 29,368 women of ages 55-69 years without a history of RA at study baseline in 1986. Diet was ascertained using a self-administered, 127-item validated food frequency questionnaire that included supplemental vitamin D use. Risk ratios (RRs) and 95% confidence intervals (95% CIs) were estimated using Cox proportional hazards regression, adjusting for potential confounders. RESULTS: Through 11 years of followup, 152 cases of RA were validated against medical records. Greater intake (highest versus lowest tertile) of vitamin D was inversely associated with risk of RA (RR 0.67, 95% CI 0.44-1.00, P for trend = 0.05). Inverse associations were apparent for both dietary (RR 0.72, 95% CI 0.46-1.14, P for trend = 0.16) and supplemental (RR 0.66, 95% CI 0.43-1.00, P for trend = 0.03) vitamin D. No individual food item high in vitamin D content and/or calcium was strongly associated with RA risk, but a composite measure of milk products was suggestive of an inverse association with risk of RA (RR 0.66, 95% CI 0.42-1.01, P for trend = 0.06). CONCLUSION: Greater intake of vitamin D may be associated with a lower risk of RA in older women, although this finding is hypothesis generating. 相似文献
64.
MH Sun G Mechtersheimer P Moellera CH Herfarth MV Knebel Doeberitz HK Scharkert T Lehnert J Gebert 《World journal of gastroenterology : WJG》2000,6(3)
AIM To study the clonality of the esophageal carcinosarcoma by using molecular approaches.METHODS Two esophageal carcinosarcomas were included in the study. Tumor area from dysplasticlesion, squamout cell carcinoma, basaloid cell carcinoma and spindle cell elements were microdissectedseparately. Each element was analyzed with 14 microsatellite markers and direct sequenced for p53 gene andras gene mutation.RESULTS Both tumors displayed a typical histologic feature of carcinosarcoma. Both cases showed thedivergent differentiation by immunohistochemistry study. In case 1 the identical LOH at p53 and hMLH1 lociwas detected. The heterogenous LOH was detected only in carcinosarcoma at RB1 and BRCA1 loci, whilethe LOH at ACTC locus was seen only in sarcoma. The same mutation of the splice site of exon 6-intron 6displayed in the two tumor elements. In case 2, a coordinate LOH at RB locus was demonstrated in threetypes of tumor elements: sqamous carcinoma, basaloid carcinoma and spindle cell element. A heterogenousLOH was seen only in spindle cells at TAP1 locus. No mutation in exon 5-8 of p53 gene has been found incase 2. No mutation of K-ras gene was found.CONCLUSION Although the different differentiation, the two elements of esophageal carcinosarcoma mayhave a single clonality. The p53 gene mutation occurred before the two differentiation directions switched.The distinct molecular genotype can be determined through molecular biological analysis. The microsatelliteprofiling can serve as an approach to find out which genetic alteration occurs before or after thedifferentiation is determines. 相似文献
65.
John H. Hunts Nobuyoshi Shimizu Tadashi Yamamoto Kumao Toyoshima Glenn T. Merlino Young-hua Xu Ira Pastan 《Somatic Cell and Molecular Genetics》1985,11(5):477-484
The epidermal growth factor (EGF) receptor, along with several oncogene protein products, possesses tyrosine-specific protein kinase activity. Furthermore, the EGF receptor has structural similarity to the putitive v-erb-B transforming protein. Because of these closely shared characteristics, it is important to elucidate the possible involvement of the EGF receptor in malignant transformation. The epidermal carcinoma cell line A431 exhibits an abnormally high number of EGF receptors, which is associated with the presence of translocation chromosome M4. Recently, A431 cells have been shown to contain amplified sequences for the EGF receptor gene(s) and also to produce a variant mRNA which diverges from the normal EGF receptor mRNA at the 3 end. Here we report, using the human EGF receptor cDNA probe pE7, that the chromosome M4 has a six-to sevenfold amplification of the EGF receptor gene. Furthermore, the presence of M4 in somatic cell hybrids correlates with the production of the variant 2.9-kb mRNA. This aberrant mRNA is apparently generated by an intrachromosomal rearrangement which was detected using as a probe a fragment of the pE15cDNA encoding the variant mRNA. 相似文献
66.
67.
68.
Acquired immunodeficiency syndrome-associated non-Hodgkin's lymphomas and other malignancies in patients with hemophilia 总被引:3,自引:0,他引:3
Ragni MV; Belle SH; Jaffe RA; Duerstein SL; Bass DC; McMillan CW; Lovrien EW; Aledort LM; Kisker CT; Stabler SP 《Blood》1993,81(7):1889-1897
Non-Hodgkin's lymphoma (NHL) is the most common human immunodeficiency virus (HIV)-associated malignancy in hemophiliacs. We studied the incidence and clinicopathologic features of NHL in 3,041 hemophiliacs followed at 18 US Hemophilia Centers between 1978 and 1989. Of the 1,295 (56.6%) who were HIV(+), 253 (19.5%) developed acquired immunodeficiency syndrome (AIDS), of whom 14 (5.5%) developed NHL. Three NHL occurred in HIV(-) hemophiliacs, for a 36.5-fold greater risk in HIV(+) than HIV(-) hemophiliacs (P < .001). The NHL incidence rate was 29-fold greater than in the US population by Surveillance, Epidemiology, and End Results (SEER) estimates (P < .001). Between 0 and 4 lymphomas have been observed per year between 1978 and 1989. At presentation 13 (92.9%) of the HIV(+) NHL were extranodal. Ten were stage IV, 1 stage II, and 3 stage IE. Ten (71.4%) were high-grade, 3 (21.4%) intermediate-grade, and 1 (7.1%) was a low-grade B-cell lymphoma. Epstein-Barr virus (EBV) DNA was detected in 36% by in situ hybridization, including one central nervous system (CNS) lymphoma. The mean CD4 cell count at NHL diagnosis was 64/mm3, the mean latency from initial HIV infection was estimated to be 59 months, and the median survival was 7 months. The incidence of basal cell carcinoma in HIV(+) hemophiliacs was 18.3-fold greater than in HIV(-) hemophiliacs (P < .001) and 11.4-fold greater than in the US population (P < .001). In conclusion, incidence rates of NHL and basal cell carcinoma in HIV(+) hemophiliacs are significantly increased over rates in HIV(-) hemophiliacs and over rates in the US population. Clinicopathologic presentation of NHL in HIV(+) hemophiliacs is similar to that in HIV(+) homosexual men. 相似文献
69.
Hematologic and immunomodulatory effects of an interleukin-1 receptor antagonist coinfusion during low-dose endotoxemia in healthy humans 总被引:3,自引:0,他引:3
Granowitz EV; Porat R; Mier JW; Orencole SF; Callahan MV; Cannon JG; Lynch EA; Ye K; Poutsiaka DD; Vannier E 《Blood》1993,82(10):2985-2990
Endotoxin is a component of gram-negative bacteria that causes hematologic and immunologic changes through its induction of cytokines. Interleukin-1 receptor antagonist (IL-1Ra) is a naturally occurring inhibitor of IL-1 that competes with IL-1 for occupancy of cell-surface receptors but possesses no agonist activity. We investigated the ability of human recombinant IL-1Ra to block the effects of low-dose endotoxin. Fourteen healthy male volunteers between 18 and 30 years old were injected intravenously with 3 ng/kg Escherichia coli endotoxin. Concurrent with the injections, nine volunteers received a 3-hour continuous intravenous infusion of IL-1Ra. The other five subjects were given a 3-hour infusion of saline. Volunteers injected with endotoxin experienced a threefold increase in circulating neutrophils over baseline. This neutrophilia was significantly reduced by 48% in subjects administered endotoxin plus IL-1Ra (P = .0253). Ex vivo mitogen-induced peripheral blood mononuclear cell proliferation decreased by greater than 60% at 3 and 6 hours after endotoxin injection (P = .0053). This endotoxin-induced reduction in mitogen response was reversed in subjects coinjected with IL-1Ra (P = .0253). Endotoxin-induced symptoms, fever, and tachycardia were unaffected by IL-1Ra. IL-1 appears to be an important mediator in endotoxemia because some of its hematologic and immunomodulatory effects can be blocked by IL-1Ra. 相似文献
70.