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1.
Massimo Bonacchi Edvin Prifti Massimo Maiani Gabriele Giunti Marzia Leacche 《European journal of cardio-thoracic surgery》2005,28(1):120-126
OBJECTIVE: The aim of this study was to evaluate the feasibility, safety and outcome of skeletonized bilateral internal mammary arteries (BIMA) in patients with unstable angina (UA) undergoing non-elective myocardial revascularization. METHODS: Between January 1997 and December 2003, 758 patients, mean age 62+/-12 years, underwent non-elective coronary artery bypass grafting (CABG) for unstable angina. Two hundred and five (27%) were operated emergently and 503 (73%) urgently. BIMA were employed in 320 (42%) patients (Group B) and isolated left IMA and/or saphenous vein grafts in the remaining 438 (58%) patients (Group M). RESULTS: In-hospital mortality (B = 5.9% and M = 5.3%), and perioperative myocardial infarction (B = 2.2%; M = 1.96%) were similar between the two groups (P = ns). Actuarial survival at 1, 3 and 7 years was 98.7, 97.5 and 96.2% in B and 99, 94.3 and 88.4% in M (P < 0.05 at 7 years follow-up). At 7 years follow-up, the event-free cardiac survival (92 vs. 87%, P = 0.021), angina-free survival (98.6 vs. 94%, P = 0.039), reoperation-free cardiac survival (98 vs. 95%, P = 0.04) and infarct-free cardiac survival (98.7 vs. 96%, P = 0.05) were better in Group B. Multivariate analysis identified age > 65 years (P = 0.02), LVEF < 35% (P = 0.01), > 1 ischemic irreversible area (P = 0.03) as independent predictors for late deaths, while the use of the LIMA (P=0.006) and both mammary arteries (P=0.001) decreased the risk of late deaths. CONCLUSIONS: The use of BIMA in non-elective CABG for UA is safe and effective. Mid-term outcome, however, are superior with improved freedom from cardiac death, from coronary reintervention and from myocardial infarction. 相似文献
2.
Spermine and spermidine, ubiquitous polyamines present in bacteria and animal cells, are also involved in cell growth. Since they interact with the double helix, they can stabilize the DNA molecule. Recent evidence of the antimutagenic and anticarcinogenic capacity of spermine has focused attention on the mechanism(s) by which such agents can protect cells from induced damages. In the present paper we show the ability of spermine and spermidine to decrease the level of sister chromatid exchanges induced in Chinese hamster ovary cells cultivated in vitro, by treating them with Psoralen + UVA irradiation (able to induce mainly monoadducts and DNA cross-links). Two different mechanisms of polyamine action can be invoked to explain the preservative activity of this class of agents. 相似文献
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4.
P. Berloco R. Pretagostini L. Poli M. Caricato A. Speziale D. Cozzi L. Gallinaro D. Alfani R. Cortesini 《Transplant international》1994,7(S1):314-317
Abstract The use of unrelated living donors in kidney transplantation is still controversial but many transplant centres have accepted this procedure. The main argument against this approach is usually an ethical one. Because of this, at our institution we accept biologically unrelated donors only if they have an emotional closeness to the recipient. From January 1983 to October 1993, out of 654 kidney transplantations we performed at our institution, 364 kidney allografts were from living donors. Of these living donors, 245 were first-degree relatives of the recipient (LRD) while 119 were unrelated (LURD); 100 cases were spouses-wife to husband in 76 cases and husband to wife in 24 cases Statistical analysis of the results (chisquare) revealed actuarial patient and graft survival rates of 89.8% and 86.8% at 1 year, 82.9% and 72.3% at 5 years and 12.3% and 60.3% at 9 years, respectively. In our series, the result of living donor kidney transplantation in this group were similar to those obtained in the LRD group, while they were significantly better than those from cadaver donors (P = 0.003). In conclusion, cadaver organs given the shortage of kidney transplantation between spouses may be a good alternative and can be performed successfully, providing a "gift of life" for both the patient and the family. 相似文献
5.
Palumbo C Ferretti M Marotti G 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2004,278(1):474-480
The present ultrastructural investigation into osteocyte dendrogenesis represents a continuation of a previous study (Ferretti et al., Anat. Embryol., 2002; 206:21-29), in which we pointed out that, during intramembranous ossification, the well-known dynamic bone formation (DBF), performed by migrating osteoblast laminae, is preceded by static bone formation (SBF), in which cords of stationary osteoblasts transform into osteocytes in the same site where they differentiated. The research was carried out on the perichondral center of ossification surrounding the mid shaft level of various long bones of chick embryos and newborn rabbits. Transmission electron microscope observations showed that the formation of osteocyte dendrites is quite different in the two types of osteogenesis, mainly depending on whether or not osteoblast movement occurs. In DBF, osteoblasts transform into small ovoidal/ellipsoidal osteocytes and their dendrites form in an asynchronous and asymmetrical manner in concomitance with, and depending on, the advancing mineralizing surface and the receding osteogenic laminae. In SBF, stationary osteoblasts give rise to big globous osteocytes, located inside confluent lacunae, with short and symmetrical dendrites that can radiate simultaneously all around their cell body because they are completely surrounded by unmineralized matrix. Contacts and gap junctions were observed between all osteocytes (both SBF- and DBF-derived) and between osteocytes and osteoblasts. Finally, a continuous osteocyte network extends throughout the bone, regardless of its static or dynamic origin. This network has the characteristic of a functional syncytium, potentially capable of modulating, by wiring transmission, the cells of the osteogenic lineage covering the bone surfaces. 相似文献
6.
Both Human Immunodeficiency Virus Cellular DNA Sequencing and Plasma RNA Sequencing Are Useful for Detection of Drug Resistance Mutations in Blood Samples from Antiretroviral-Drug-Naive Patients 下载免费PDF全文
7.
Marchetti G Cozzi B Tavanti M Russo V Pellegrini S Fabiani O 《Journal of chemical neuroanatomy》2000,20(2):129-139
The present study reports the distribution of Neuropeptide Y (NPY)-immunoreactive neurons and fibers in the forebrain of the adult carp Cyprinus carpio L. Serial Nissl-stained sections were used for cytoarchitecture and identification of anatomical structures. Immunostaining of NPY-containing neurons and fibers was used as neurochemical marker and tool for comparison with other species, including the goldfish.The general outline of the cytoarchitecture of the carp forebrain is similar to that of other Cypriniformes. However, using NPY immunohistochemistry, we found several specific differences with the goldfish, especially in the diencephalon. In the hypothalamus of the carp NPY-immunoreactive (NPYir) neurons were identified in the n. dorsolateralis thalami, and in the n. ventralis lateralis thalami. In the same location, we observed the n. anterior hypothalami and the n. preglomerulosus pars lateralis, described in the goldfish, as parts of n. prerotundus. However, in the carp we were not able to identify a n. preglomerulosus pars medialis, a n. preglomerulosus pars medialis commissuralis and a n. glomerulosus. We describe a n. rotundus, in which we did not find substructures typical of the goldfish.Further differences with the goldfish, trout and salmon were also noted. 相似文献
8.
Clinical,immunological, and molecular analysis in a large cohort of patients with X-linked agammaglobulinemia: an Italian multicenter study 总被引:5,自引:0,他引:5
Plebani A Soresina A Rondelli R Amato GM Azzari C Cardinale F Cazzola G Consolini R De Mattia D Dell'Erba G Duse M Fiorini M Martino S Martire B Masi M Monafo V Moschese V Notarangelo LD Orlandi P Panei P Pession A Pietrogrande MC Pignata C Quinti I Ragno V Rossi P Sciotto A Stabile A;Italian Pediatric Group for XLA-AIEOP 《Clinical immunology (Orlando, Fla.)》2002,104(3):221-230
A questionnaire-based retrospective clinical and immunological survey was conducted in 73 males with a definite diagnosis of X-linked agammaglobulinemia based on BTK sequence analysis. Forty-four were sporadic and 29 familial cases. At December 2000, the patients' ages ranged from 2 to 33 years; mean age at diagnosis and mean duration of follow-up were 3.5 and 10 years respectively. After the mid-1980s all but 2 were on intravenous immunoglobulin (IVIG) substitution therapy, with residual IgG >500 mg/dl in 94% of the patients at the time of enrollment. Respiratory infections were the most frequent manifestation both prior to diagnosis and over follow-up. Chronic lung disease (CLD) was present in 24 patients, in 15 already at diagnosis and in 9 more by 2000. The cumulative risk to present at diagnosis with CLD increased from 0.17 to 0.40 and 0.78 when the diagnosis was made at the ages of 5, 10, and 15 years respectively. For the 9 patients who developed CLD during follow-up, the duration of follow-up, rather than age at diagnosis; previous administration of intramuscular immunoglobulin; and residual IgG levels had a significant effect on the development of CLD. Chronic sinusitis was present in 35 patients (48%), in 15 already at diagnosis and in 20 by 2000. Sistemic infections such as sepsis and meningitis/meningoencephalitis decreased over follow-up, probably due to optimal protection provided by high circulating IgG levels reached with IVIG. 相似文献
9.
Peyvandi F Tagliabue L Menegatti M Karimi M Komáromi I Katona E Muszbek L Mannucci PM 《Human mutation》2004,23(1):98
Factor XIII (FXIII) deficiency is a very rare severe autosomal bleeding disorder with a frequency of 1:2,000,000 in the general population and only a few patients have been genetically characterized so far. We report a phenotype-genotype characterization of 10 unrelated Iranian patients. Two FXIII (transglutaminase) activity assays showed no FXIII activity, except a conserved residual activity in patients receiving prophylactic substitution treatment. FXIII antigen concentrations measured by two immunoassays were comparable. Genotype characterization identified four novel mutations (2 missense and 2 small deletions) and two previously reported missense mutations in the FXIII A subunit gene (F13A). Molecular modeling was carried out to reveal the structural consequences of the missense mutations, that caused the replacement of an arginine residue involved in the formation of structurally important extensive hydrogen-bonded network. The replacements [c.320G>A (p.Arg77His) in the beta-sandwich, c.868C>T (p.Arg260Cys), c.869G>A (p.Arg260His) and c.1236G>T (p.Arg382Ser) in the core domain] resulted in the loss or impairment of such H-bonded network. Energy decomposition analysis demonstrated that this situation leads to the instability and perhaps to the incorrect folding of the A subunit, that would explain the development of severe FXIII deficiency. 相似文献
10.
Hepatic arterial perfusion scintigraphy with Tc-99m-MAA. Use of a totally implanted drug delivery system 总被引:2,自引:0,他引:2
H A Ziessman J H Thrall P J Yang S C Walker E A Cozzi J E Niederhuber J W Gyves W D Ensminger M C Tuscan 《Radiology》1984,152(1):167-172
Tc-99m-MAA hepatic arterial perfusion scintigraphy ( HAPS ) using a totally implanted drug delivery system was employed for hepatic arterial chemotherapy in 147 patients (335 studies). Complete perfusion of the involved liver was seen in 88% of patients initially [more so in those with normal hepatic vascular anatomy (93%) than those with vascular variants (79%)] and remained good on follow-up. In 67 consecutive patients (95 studies), arteriovenous shunting to the lung ranged from 0.4 to 32% (mean, 6.2% +/- 4.1 S.D.). Uptake at the tip of the catheter was increased in 20% of patients, but good perfusion was usually maintained. A significant decrease in hepatic and/or extrahepatic perfusion associated with a "hot spot" at the tip of the catheter indicated hepatic arterial thrombosis. Extrahepatic perfusion was seen in 14% of cases, usually in the distribution of the stomach, small bowel, and spleen. Significant symptoms of drug toxicity were seen in 70% of patients with extrahepatic perfusion, compared to 19% of those without it. 相似文献