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排序方式: 共有1007条查询结果,搜索用时 15 毫秒
1.
The records of obese and nonobese victims of blunt trauma were compared to determine if obese individuals are predisposed to a specific injury pattern. Prospectively collected data on 6368 adults admitted to a level I trauma center over a 4-year period were analyzed. Twelve percent (743 patients) met Body Mass Index (weight/height2) criteria for obesity (greater than or equal to 30 kg/m2). The obese group was older (p less than 0.01) and had lower ISSs (p less than 0.05) and higher GCS scores (p less than 0.01). More obese patients were injured in vehicular crashes (62.7% vs. 54.1% [p less than 0.01]). The obese victims were more likely to have rib fractures, pulmonary contusions, pelvic fractures, and extremity fractures and less likely to have incurred head trauma and liver injuries (p less than 0.05). Obese people injured in vehicular crashes had a similar injury pattern with no difference in seating position, direction of impact, seat belt use, and ejection. 相似文献
2.
Perfluorochemicals as US contrast agents for tumor imaging and hepatosplenography: preliminary clinical results 总被引:3,自引:0,他引:3
Mattrey RF; Strich G; Shelton RE; Gosink BB; Leopold GR; Lee T; Forsythe J 《Radiology》1987,163(2):339-343
In animals, perfluorochemicals (PFCs) are effective ultrasound (US) contrast agents that produce hepatic, splenic, and tumor enhancement. The use of Fluosol-DA 20%, an emulsion of perfluorodecalin and perfluorotripropylamine, was studied in nine non-critically ill patients with cancer who had liver lesions. US studies without Fluosol were compared with studies obtained 24, 48, and 72 hours after Fluosol infusion. Vital signs and extensive laboratory analyses are performed before and after Fluosol infusion. Liver metastases from colonic, pancreatic, and gastric carcinoma exhibited rim or diffuse enhancement after a Fluosol dose of 1.6 g/kg or greater. Fluosol produced echogenic enhancement of the liver and spleen relative to kidney at a dose of 2.4 g/kg, allowing the detection of nonenhancing lesions. In addition, Fluosol at a dose of 1.6 g/kg or greater allowed detection of lesions not seen before contrast medium was administered in three of the seven patients studied. There was a mild increase in the level of serum glutamic oxaloacetic transaminase in two patients, one given 2.4 and the other 3.2 g/kg of Fluosol. Mild and transient allergic reactions without change in vital signs were experienced by two patients. 相似文献
3.
Classical and anaplastic seminoma: difference in survival 总被引:1,自引:0,他引:1
Classical and anaplastic seminoma are traditionally treated with radiation therapy and are said to have the same prognosis. A retrospective study was undertaken of 90 seminoma patients treated with radiation therapy between 1961 and 1985. The classical group consisted of 71 patients of whom 50 had stage I and 21 had stage II disease. The anaplastic group consisted of 19 patients of whom ten had stage I and nine had stage II disease. The median follow-up time was 64 months for the entire group. The 10-year relapse-free survival rate for the classical group was 94% and for the anaplastic group was 70% (P less than .05). For patients with classical stage I disease, the relapse-free actuarial survival rate was 98%; for patients with anaplastic stage I disease, it was 64% (P less than .02). For the classical stage II disease group, the relapse-free actuarial survival rate was 84% and for the anaplastic stage II disease group, 75% (P less than .70). Four patients in the classical group (6%) had relapses; of these, one patient had local recurrence of tumor, and three had distant metastases. In the anaplastic group, four patients (21%) had relapses; two patients had local recurrence of tumor, and two had distant metastases. Therefore the data suggest a difference in survival and relapse rates between classical and anaplastic seminoma. 相似文献
4.
Sandrine Cappellesso Jean-Fran?ois Valentin Bruno Giraudeau Marie-Denise Boulanger Azmi Al-Najjar Mathias Büchler Jean-Michel Halimi Hubert Nivet Pierre Bardos Yvon Lebranchu Hervé Watier 《Nephrology, dialysis, transplantation》2004,19(2):439-443
BACKGROUND: Genetic factors other than HLA have been reported to be associated with the outcome of organ transplantations. Because binding of FasL to its receptor Fas could play an important role in tubulitis and in the death of graft tubular epithelial cells during kidney allograft rejection, a gene polymorphism recently identified in position -671 in the promoter of the TNFRSF6 gene coding for Fas was investigated in donors. METHODS: A case-control study was performed within a cohort of non-hyperimmunized adult patients who had received cadaveric kidney transplants based on the occurrence or absence of acute cellular rejection in the first 6 months after renal transplantation. Each recipient from the acute rejection group (n = 35) was matched for age (+/- 5 years) and number of HLA-DR mismatches with two recipients within the non-acute rejection group (n = 70). RESULTS: The TNFRSF6-GG genotype was more frequent in donors in the group without rejection episodes. In contrast, patients who received a kidney from a TNFRSF6-A carrier were more likely to experience acute rejection episodes (relative risk nearly 2.1). CONCLUSION: This study suggests that donor TNFRSF6 polymorphism directly or indirectly influences acute kidney rejection episodes. 相似文献
5.
6.
Summary— Experiments were designed to determine whether or not indapamide, an antihypertensive agent with vasodilator properties, inhibits endothelium-dependent contractions. Rings of aortae with and without endothelium from spontaneously hypertensive rats (SHR) were suspended in conventional organ chambers for the measurement of isometric force. Acetylcholine and adenosine diphosphate-β-S in the presence of a nitric oxide synthase inhibitor, caused endothelium-dependent contractions, which were inhibited by indapamide. The compound (10−4 M) also slightly reduced the contractions of rings without endothelium evoked by U-46,619, which activates thromboxane-endoperoxide receptors. These results demonstrate that indapamide inhibits endothelium-dependent contractions in the SHR aorta, and suggest that the inhibition is due, at least in part, to the action of the drug on the hypertensive vascular smooth muscle. 相似文献
7.
Structure of an autoimmune T cell receptor complexed with class II peptide-MHC: insights into MHC bias and antigen specificity 总被引:1,自引:0,他引:1
Maynard J Petersson K Wilson DH Adams EJ Blondelle SE Boulanger MJ Wilson DB Garcia KC 《Immunity》2005,22(1):81-92
T cell receptor crossreactivity with different peptide ligands and biased recognition of MHC are coupled features of antigen recognition that are necessary for the T cell's diverse functional repertoire. In the crystal structure between an autoreactive, EAE T cell clone 172.10 and myelin basic protein (1-11) presented by class II MHC I-Au, recognition of the MHC is dominated by the Vbeta domain of the TCR, which interacts with the MHC alpha chain in a manner suggestive of a germline-encoded TCR/MHC "anchor point." Strikingly, there are few specific contacts between the TCR CDR3 loops and the MBP peptide. We also find that over 1,000,000 different peptides derived from combinatorial libraries can activate 172.10, yet the TCR strongly prefers the native MBP contact residues. We suggest that while TCR scanning of pMHC may be degenerate due to the TCR germline bias for MHC, recognition of structurally distinct agonist peptides is not indicative of TCR promiscuity, but rather highly specific alternative solutions to TCR engagement. 相似文献
8.
Elastin point mutations cause an obstructive vascular disease, supravalvular aortic stenosis 总被引:7,自引:2,他引:7
Li DY; Toland AE; Boak BB; Atkinson DL; Ensing GJ; Morris CA; Keating MT 《Human molecular genetics》1997,6(7):1021-1028
Supravalvular aortic stenosis (SVAS) is an inherited obstructive vascular
disease that affects the aorta, carotid, coronary and pulmonary arteries.
Previous molecular genetic data have led to the hypothesis that SVAS
results from mutations in the elastin gene, ELN. In these studies, the
disease phenotype was linked to gross DNA rearrangements (35 and 85 kb
deletions and a translocation) in three SVAS families. However, gross
rearrangements of ELN have not been identified in most cases of autosomal
dominant SVAS. To define the spectrum of ELN mutations responsible for this
disorder, we refined the genomic structure of human ELN and used this
information in mutational analyses. ELN point mutations co-segregate with
the disease in four familial cases and are associated with SVAS in three
sporadic cases. Two of the mutations are nonsense, one is a single base
pair deletion and four are splice site mutations. In one sporadic case, the
mutation arose de novo. These data demonstrate that point mutations of ELN
cause autosomal dominant SVAS.
相似文献
9.
Robert Maggisano MD Avery Nathens MD Natalia A. Alexandrova MD Claudio Cina MD Bernard Boulanger MD Robert McKenzie MD Allan W. Harrison MD 《Annals of vascular surgery》1995,9(1):44-52
Although the traditional therapy for blunt traumatic rupture of the thoracic aorta (TRA) is immediate operative repair, there may be a selective role for delayed repair, particularly in patients with head trauma, respiratory failure, or cardiac dysfunction. The present study examines the hypothesis that TRA can be managed by selective delayed operative repair. Clinical data were collected from 59 consecutive patients with TRA at a regional trauma unit. All TRAs were at the aortic isthmus. Patients were retrospectively classified into three groups: group I (n=12) included patients who either arrived in extremis or rapidly became unstable during triage; group II (n=3) included patients who had no contraindications to early repair and underwent repair at the time of diagnosis; and group III (n=44) consisted of patients who because of concomitant injuries or sepsis required initial admission and management in the intensive care unit until their clinical status had improved sufficiently to allow for deliberate delayed operative repair of the TRA. The delay ranged from 1 day to 7 months. Eight patients have yet to undergo repair and remain well at follow-up from 1 to 4 years. Overall survival rates in groups I, II, and III were 17%, 100%, and 82%, respectively. The surgery-related mortality rate in group III was 10% (three patients). Only two (4.5%) patients in group III died as a result of a ruptured aorta within 72 hours of admission. In conclusion, contrary to surgical doctrine, TRA may not require immediate operative repair in all cases, but may instead be managed selectively depending on the patient's clinical status. 相似文献
10.