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21.
Accelerating cardiac cine 3D imaging using k-t BLAST. 总被引:1,自引:0,他引:1
Sebastian Kozerke Jeffrey Tsao Reza Razavi Peter Boesiger 《Magnetic resonance in medicine》2004,52(1):19-26
By exploiting spatiotemporal correlations in cardiac acquisitions using k-t BLAST, gated cine 3D acquisitions of the heart were accelerated by a net factor of 4.3, making single breathhold acquisitions possible. Sparse sampling of k-t space along a sheared grid pattern was implemented into a cine 3D SSFP sequence. The acquisition of low-resolution training data, which was required to resolve aliasing in the k-t BLAST method, was either interleaved into the sampling process or obtained in a separate prescan to allow for shorter breathhold durations in patients with heart disease. Volumetric datasets covering the heart with 20 slices at a spatial resolution of 2 x 2 x 5 mm3 were recorded with 20 cardiac phases in a total breathhold duration of 25-27 sec, or 18 sec if partial Fourier sampling was additionally employed. The feasibility of the method was demonstrated on healthy volunteers and on patients. The comparison of endocardial area derived from single slices of the 3D dataset with values extracted from separate single-slice acquisitions showed no significant differences. By shortening the acquisition substantially, k-t BLAST may greatly facilitate volumetric imaging of the heart for evaluation of regional wall motion and the assessment of ventricular volume and ejection fraction. 相似文献
22.
Othman Shibly Robert E. Schifferle Sebastian G. Ciancio Majd Tarakji Maryanne L. Mather 《Journal of clinical periodontology》1997,24(4):260-263
Abstract A single blind 30 day study compared the reduction of plaque and gingivitis for the Hapika® Powerbrush to the Interplak® ultra 10 tuft. A longitudinal parallel group design was utilized and screening evaluation was performed to determine patient eligibility prior to study enrollment. 66 subjects were entered into the study and assigned to 1 of 2 groups, each using one of the toothbrushes. At baseline, subjects received an oral soft tissue exam, a dental hard tissue exam, and were scored by the Lobene modification of the Löe and Silness gingival index (GI). Plaque was then disclosed and scored both pre and post brushing using the modified Turesky plaque/debris examination and an interproximal bleeding examination was performed post-brushing. On days 15 and 30, after an oral soft tissue and GI examination, plaque was graded by the Modified Turesky plaque/debris exam. Subjects then brushed and were graded by the Modified Turesky plaque/debris examination and an interproximal bleeding index examination. The results showed that both brushes provided a similar change in clinical indices. All produced a statistically significant reduction from baseline to day 30 for the gingival index (26.5-29.1%), the bleeding index (13.8-24.1%), and the plaque index (16.9-19.4%), A comparison of pre and post brushing scores for the plaque index at 30 showed that both brushes reduced plaque similarly with a statistically significant reduction (P<0.05) from their pre-brushing plaque index scores at all time periods. 相似文献
23.
Edward Golec Sebastian Nowak Roman Go?dzialski Micha? Godyń 《Chirurgia narzadów ruchu i ortopedia polska》2003,68(3):185-189
In this paper the authors evaluate the long-term results of treatment for articular calcaneus fractures with Westhues method. This evaluation is performed with regard to triple measurement of B?hler's angle value and to subjective criteria. The clinical material from years 1985-2002 consists of 47 patients aged between 24 and 56 years (mean age 32 years) with articular calcaneus fractures--namely, 41 male patients (87.2%) and 6 female patients (12.8%). The follow-up examination was performed in 24 patients (51% of all patients), namely, in 23 male patients (48.8%) and in one female patient (2.2%). Minimum follow-up time was 12 months and maximum was 9 years. Acquired results suggest that Westhues method restores normal B?hler's angle value only in tongue-type calcaneous fractures. 相似文献
24.
Venöse Thromboembolien (VTE) stellen eine häufige Morbiditäts- und Mortalitätsursache dar; die jährliche Inzidenz wird mit etwa 1 : 1 000 angegeben. Dabei sind verschiedene Risikogruppen zu unterscheiden, die sowohl durch endogene Faktoren (z. B. genetisch deteminierte Thrombophilie), viel häufiger aber durch exogene Faktoren (zugrundeliegende Erkankung) charakterisiert werden. Diese Heterogenität resultiert in Besonderheiten bei Prophylaxe und Therapie von VTE, auf die in dieser Darstellung eingegangen werden soll. 相似文献
25.
Is neurogenesis reparative after status epilepticus? 总被引:1,自引:0,他引:1
26.
René?G?ddeEmail author Stefanie?Brune Peter?Jagiello Eckhart?Sindern Michael?Haupts Sebastian?Schimrigk Norbert?Müller J?rg?T?Epplen 《Journal of negative results in biomedicine》2005,4(1):7
Apoptosis, the programmed death of cells, plays a distinct role in the etiopathogenesis of Multiple sclerosis (MS), a common
disease of the central nervous system with complex genetic background. Yet, it is not clear whether the impact of apoptosis
is due to altered apoptotic behaviour caused by variations of apoptosis-related genes. Instead, apoptosis in MS may also represent
a secondary response to cellular stress during acute inflammation in the central nervous system. Here, we screened 202 apoptosis-related
genes for association by genotyping 202 microsatellite markers in initially 160 MS patients and 160 controls, both divided
in 4 sets of pooled DNA samples, respectively. When applying Bonferroni correction, no significant differences in allele frequencies
were detected between MS patients and controls. Nevertheless, we chose 7 markers for retyping in individual DNA samples, thereby
eliminating 6 markers from the list of candidates. The remaining candidate, the ERBB3 gene microsatellite, was genotyped in additional 245 MS patients and controls. No association of the ERBB3 marker with the disease was detected in these additional cohorts. In consequence, we did not find further evidence for apoptosis-related
genes as predisposition factors in MS. 相似文献
27.
Glial cell expression of hepatocyte growth factor in vitreoretinal proliferative disease 总被引:5,自引:0,他引:5
Hollborn M Krausse C Iandiev I Yafai Y Tenckhoff S Bigl M Schnurrbusch UE Limb GA Reichenbach A Kohen L Wolf S Wiedemann P Bringmann A 《Laboratory investigation; a journal of technical methods and pathology》2004,84(8):963-972
The hepatocyte growth factor (HGF) has been crucially implicated in the development of proliferative retinal diseases; however, it is unclear whether retinal glial cells express or respond to HGF. Therefore, we examined the expression of HGF and of the receptor for HGF, c-Met, by immunohistochemical costaining with glial fibrillary acidic protein (GFAP) in epiretinal membranes of patients with proliferative vitreoretinopathy (PVR) and proliferative diabetic retinopathy (PDR), respectively. Furthermore, it was determined whether cells of the human retinal glial cell line, MIO-M1, secrete HGF protein, and whether HGF stimulates proliferation and chemotaxis, and secretion of the vascular endothelial growth factor (VEGF). Neuroretinas of patients with PVR express elevated mRNA level for HGF in comparison to control retinas. In epiretinal membranes of patients with PVR or PDR, immunoreactivity for HGF and for c-Met, respectively, partially colocalized with immunoreactivity for GFAP. Fetal bovine serum and basic fibroblast growth factor, but not heparin-binding epidermal or platelet-derived growth factors, evoked HGF secretion by cultured retinal glial cells. HGF displayed only a marginal effect on cell proliferation while it stimulated chemotaxis. HGF promoted the secretion of VEGF, via activation of the phosphatidylinositol-3 kinase. It is concluded that glial cells in epiretinal membranes express both HGF protein and c-Met receptors. The results suggest an autocrine/paracrine role of HGF in glial cell responses during proliferative vitreoretinal disorders as well as in retinal neovascularization, by stimulating of VEGF release. 相似文献
28.
29.
Class switch recombination (CSR), somatic hypermutation, and gene conversion are immunoglobulin diversification mechanisms that are strictly dependent on the activity of the activation-induced cytidine deaminase (AID). The precise role and substrate(s) of AID in these processes remain to be well defined. The closest homologue of AID is APOBEC-1, a bona fide mRNA-editing enzyme, which shares with AID the ability to deaminate cytidines within single-stranded DNA in vitro and in prokaryotic cells. To determine whether APOBEC-1 can therefore substitute for AID in activated B cells, we expressed human AID, a catalytic mutant thereof, and rat APOBEC-1 in AID-deficient murine B cells. Whereas AID rescued CSR, neither the inactive mutant nor APOBEC-1 could complement AID deficiency. This indicates that cytidine deaminase activity is necessary but not sufficient to initiate CSR, and suggests that AID is specifically targeted to its cognate substrate, the immunoglobulin genes or a distinct mRNA, by an as-yet-unknown mechanism. 相似文献
30.
How many lymph nodes are necessary to stage early and advanced adenocarcinoma of the sigmoid colon and upper rectum? 总被引:5,自引:0,他引:5
Leibl S Tsybrovskyy O Denk H 《Virchows Archiv : an international journal of pathology》2003,443(2):133-138
The lymph-node yields in specimens resected for colorectal adenocarcinoma show considerable variations, raising the question whether the minimum lymph-node number recommended by the UICC (International Union Against Cancer) for pN0 classification represents an appropriate quality standard for specimen work-up. The number of pericolic lymph nodes recovered from 568 archival surgical colorectal carcinoma specimens located in the sigmoid or upper rectum showed a highly statistically significant correlation with both the pT category and the presence of metastases (P<0.0005). The median lymph-node yield in standardized (i.e., resembling in size surgically removed cancer specimens) tumor-free specimens obtained during autopsies was 13 lymph nodes, compared with 20.5 when diverticula were present and more than 30 in specimens with chronic inflammation or from patients with systemic infections. In 48 pT2 and pT3 carcinoma specimens prospectively dissected in the same way, median numbers of 18 (pT2) and 23 (pT3) lymph nodes were detected (range between 8 and 39 nodes). The lymph-node numbers recommended in previous studies and by the UICC often seem to be too low to declare a specimen free of metastases. Although the great variation in lymph-node counts requires the recovery of all lymph nodes for pN0 classification, recommendations considering the pT status and additional factors like diverticula and inflammatory changes can be useful as a quality standard for specimen work up. 相似文献