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21.
John C. Norman Clifford C. Dacso George J. Reul Edward K. Massin Tomas Klima Barry D. Kahan John T. Reiser Denton A. Cooley 《Artificial organs》1978,2(4):413-420
The abdominal left ventricular assist device (ALVAD) is an order of magnitude more effective than conventional intra-aortic balloon pumping (IABP) in unloading and providing circulatory support to the failing left ventricle. This is a report of a unique case which demonstrates that in the absence of pulmonary vascular obstruction or constriction, the ALVAD can substitute for both left and right heart function. A 21-year-old patient with a congenital bicuspid aortic valve developed acute valvular endocarditis which rapidly progressed to congestive heart failure. An operation was undertaken, the mitral and aortic valves were excised and replaced by porcine heterografts, and a fistula from the right sinus of Valsalva to the right ventricle was closed. When coronary circulation was restored, irreversible ischemic contracture of the left ventricle, or "stone heart" syndrome, developed and emergency ALVAD or partial artificial heart implantation was effected. This device functioned as a total artificial heart for nearly six days, while a donor heart was sought. The patient then underwent removal of the ALVAD and cardiac and renal allografting. The transplanted heart functioned well, but the patient expired fifteen days later from gram-negative sepsis. 相似文献
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A small dose of isoprenaline or saline was administered intraperitoneally to rats 20 min before the administration of one of the amino acids l-dopa or l-tryptophan. Isoprenaline caused a marked increase in the brain concentration of the administered amino acid. Isoprenaline has previously been shown to cause a decrease in at least some of those plasma amino acids which compete with l-dopa and tryptophan for carrier-mediated transport into the brain. The effect of isoprenaline on the concentrations of dopa and tryptophan in the brain is suggested to be at least partly caused by a change in the relationship between endogeneous and administered amino acids. It is also possible that a direct effect of isoprenaline on the blood-brain barrier transport system contributes to the effect.The reported finding might be of clinical interest in view of the therapeutic importance of aromatic amino acids with a central site of action. 相似文献
24.
Tomas Norlander Sam-Hyun Kwon Gert Henriksson Karl Magnus Westrin Karin Sandstedt Pontus Stierna 《The Laryngoscope》1998,108(3):411-417
To investigate possible effects of corticosteroids on polyp formation and local bacterial colonization, pneumococcal sinusitis was experimentally induced in rabbits pretreated with betamethasone or saline. After 7 days, macroscopic polyps were counted post-mortem and on histologic slides after serial sectioning. Histologic sections were also examined with light microscopy. Macroscopic polyps were significantly fewer in animals given betamethasone, while there was no difference regarding the number of microscopic polyps. Ingrowth of pathogenic microorganisms was found in five of eight rabbits given placebo but in none of the animals treated with corticosteroids (P < 0.05). The reduced number of pathogenic strains in these animals may be explained by a better-preserved local host defense. The lower number of macroscopic polyps in the same animals could be because of a delayed mucosal repair and subsequent polyp formation. 相似文献
25.
Darcy KM Brady WE McBroom JW Bell JG Young RC McGuire WP Linnoila RI Hendricks D Bonome T Farley JH;Gynecologic Oncology Group 《Gynecologic oncology》2008,111(3):487-495
ObjectiveThe Gynecologic Oncology Group (GOG) performed a detailed analysis of p53 overexpression in previously-untreated women with invasive early or advanced stage epithelial ovarian cancer (EOC).MethodsWomen were eligible for the study if they provided a tumor block for translational research and participated in either GOG-157, a randomized phase III trial of three versus (vs.) six cycles of paclitaxel + carboplatin in high-risk, early stage EOC, or GOG-111, a randomized phase III trial of cyclophosphamide + cisplatin vs. paclitaxel + cisplatin in suboptimally-resected, advanced stage EOC. The N-terminal DO-7 p53 antibody was used to examine the expression of the major normal and mutant p53-isoforms. p53 overexpression was defined as ≥ 10% tumor cells exhibiting nuclear staining.Resultsp53 was overexpressed in 51% (73/143) and 66% (90/136) of cases in the GOG-157 and GOG-111 cohorts, respectively. In the GOG-157 cohort, p53 overexpression was not associated with any clinical characteristics or overall survival (OS) but was associated with worse progression-free survival (PFS) (logrank test: p = 0.013; unadjusted Cox modeling: p = 0.015). In the GOG-111 cohort, p53 overexpression was associated with GOG performance status (p = 0.018) and grade (p = 0.003), but not with age, stage, cell type or with tumor response and disease status after primary chemotherapy, PFS or OS. Adjusted Cox regression modeling demonstrated that p53 overexpression was not an independent prognostic factor for PFS or OS in either cohort.Conclusionsp53 overexpression assessed by DO-7 immunostaining is common in early and advanced stage EOC, but has limited prognostic value in women treated with surgical staging and platinum-based combination chemotherapy. 相似文献
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Originally applied to alpha oscillations in the 1970s, microstate (MS) analysis has since been used to decompose mainly broadband electroencephalogram (EEG) signals (e.g., 1–40 Hz). We hypothesised that MS decomposition within separate, narrow frequency bands could provide more fine‐grained information for capturing the spatio‐temporal complexity of multichannel EEG. In this study, using a large open‐access dataset (n = 203), we first filtered EEG recordings into four classical frequency bands (delta, theta, alpha and beta) and thereafter compared their individual MS segmentations using mutual information as well as traditional MS measures (e.g., mean duration and time coverage). Firstly, we confirmed that MS topographies were spatially equivalent across all frequencies, matching the canonical broadband maps (A, B, C, D and C′). Interestingly, however, we observed strong informational independence of MS temporal sequences between spectral bands, together with significant divergence in traditional MS measures. For example, relative to broadband, alpha/beta band dynamics displayed greater time coverage of maps A and B, while map D was more prevalent in delta/theta bands. Moreover, using a frequency‐specific MS taxonomy (e.g., ϴA and αC), we were able to predict the eyes‐open versus eyes‐closed behavioural state significantly better using alpha‐band MS features compared with broadband ones (80 vs. 73% accuracy). Overall, our findings demonstrate the value and validity of spectrally specific MS analyses, which may prove useful for identifying new neural mechanisms in fundamental research and/or for biomarker discovery in clinical populations. 相似文献
28.
Tomas V. Gonzalez Tiffany M. Sae-Kho Steven I. Robinson Tina J. Hieken Andrew L. Folpe Stephen M. Broski Amy C. Degnim Katrina N. Glazebrook 《Radiology Case Reports》2022,17(10):3624
Radiation-associated angiosarcoma of the breast (RAASB) is a rare and aggressive malignancy occurring after radiation therapy as part of breast cancer treatment. RAASB usually presents several years after prior radiation and typically involves the skin with or without involvement of the parenchyma. Most RAASB are detected as cutaneous changes on physical exam. Herein, we present a unique case of a clinically occult RAASB diagnosed as non-mass enhancement on annual surveillance breast MRI. 相似文献
29.
Immune checkpoint inhibitors (ICIs) have been associated with neurological immune related adverse events (irAE-N) and patients with ICI toxicity may present with neurological or ocular symptoms. Furthermore, patients on ICI may initially present to oncology or neurology. We report a case series of 3 patients treated with ICIs presenting with diplopia or ptosis, found to have concurrent myocarditis in addition to immune-related myopathy (irMyopathy) or myasthenia gravis (irMG). None of the patients described cardiac symptoms, underscoring the importance of screening for myocarditis in patients presenting with diplopia and/or other neuromuscular symptoms which may suggest either irMyopathy or irMG. 相似文献
30.
Dr. Tomas M. Heimann M.D. Adrian J. Greenstein M.D. Karen Bolnick R.N. Steven Yoelson B.A. Arthur H. Aufses Jr M.D. 《Diseases of the colon and rectum》1985,28(9):658-661
The records of all patients with familial polyposis coli and ulcerative colitis operated at The Mount Sinai Hospital were
reviewed to determine the proportion of patients with cancer at the time of colon resection. Sixty-nine patients with familial
polyposis coli undergoing operation between 1947 and 1983 were identified and 25 (36 percent) were found to have cancer. In
the group with ulcerative colitis, 548 patients had surgical treatment between 1957 and 1983 and 65 (12 percent) had colonic
cancer. There was a significant decrease in the proportion of patients with familial polyposis coli having cancer at the time
of colon resection from 50 percent before 1968 to 20 percent since 1978. This change in cancer incidence was found to correlate
with a decrease in the mean age at operation from 40 to 25 years. In the group with ulcerative colitis, the mean age at operation
has remained essentially unchanged at 36 years. The proportion of patients with ulcerative colitis having cancer at the time
of colon resection has remained constant throughout this study. Progression to carcinoma is still a significant concern in
both familial polyposis coli and ulcerative colitis. Although removal of the colon and rectum prevents cancer development,
patient selection and timing of the operation remain a difficult problem. 相似文献