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991.
van Den Boom R Lesnik Oberstein SA van Duinen SG Bornebroek M Ferrari MD Haan J van Buchem MA 《Radiology》2002,224(3):791-796
PURPOSE: To assess the prevalence and distribution of subcortical lacunar lesions (SLLs) in patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), to determine whether SLLs are an abnormal finding by studying their prevalence in healthy subjects, and to assess whether SLLs occur in other conditions associated with small vessel disease and white matter areas of high signal intensity (WMH). MATERIALS AND METHODS: The presence of SLLs, their location, and their relation to other abnormalities were assessed on magnetic resonance (MR) images (T1-weighted, T2-weighted, and fluid-attenuated inversion-recovery) obtained in 34 CADASIL patients and 20 healthy family members. Three additional control groups of healthy volunteers, elderly patients with vascular risk factors, and patients with another hereditary small vessel disease were also screened for the presence and location of SLLs. Sensitivity and specificity of the presence of SLLs for the diagnosis of CADASIL were assessed. RESULTS: SLLs were found in 20 (59%) of CADASIL patients. Incidence of SLLs increased with age (20%, <30 years; 50%, 30-50 years; 80%, >50 years). SLLs invariably occurred in the anterior temporal lobes and in areas where diffuse WMH expanded into arcuate fibers. From the anterior temporal lobe, the lesions could extend dorsally into the temporal lobes and rostrally into the frontal lobes. Lesions were not found in the parietal and occipital lobes. None of the control subjects had SLLs. Specificity and sensitivity of SLLs for CADASIL were 100% and 59%, respectively. CONCLUSION: SLLs are an abnormal finding at MR imaging that frequently occur in CADASIL patients. 相似文献
992.
Yang P Yokomizo A Tazelaar HD Marks RS Lesnick TG Miller DL Sloan JA Edell ES Meyer RL Jett J Liu W 《Lung cancer (Amsterdam, Netherlands)》2002,35(3):221-229
PURPOSE: Survival of lung cancer patients has been dismal. Glutathione enzymes are directly involved in the metabolism of platinum compounds, a group of important chemotherapeutic drugs in cancer treatment. We tested the hypothesis that genes encoding glutathione enzymes may predict lung cancer short-term survival. METHODS: We studied DNA polymorphisms of 250 primary lung cancer patients at four glutathione-related loci: GSTP1, GSTM1, GSTT1 and gamma-GCS that encode glutathione-S-transferase-pi, glutathione-S-transferase-mu, glutathione-S-transferase-theta, and gamma-glutamylcysteine synthetase, respectively. Pearson's chi(2)-square tests, Kaplan-Meier survival curves, log rank tests, and Cox regression models were applied in the analysis. RESULTS: There were 150 (60%) men and 100 (40%) women in this study. Seventeen percent of the patients had never smoked cigarettes, and 61% had stopped smoking at least 6 months prior to their lung cancer diagnosis. Among never smokers, those with null (N) or low (L) genotype experienced a better 1-year-survival rate than those with a positive (P) or high (H) genotype. Patients with P or H at two loci (PP or PH) were compared with patients with N or L at one or both loci (other). Among never smokers, 1-year-survival rates were 60-78% for patients with PP or PH genotypes compared with 89-100% for other types. The survival advantage was greater among advanced-stage patients who were NL or NN than low-stage patients. Similar results were not observed among smokers. CONCLUSIONS: Glutathione-related genes may determine lung cancer survival. Our results, if confirmed, would suggest new directions to enhance cancer treatment, and provide easily measurable markers for clinicians to plan patient-specific therapy. 相似文献
993.
994.
Previous reports have presented validation studies of magnetic resonance (MR) image synthesis in which multiple spin-echo (MSE) source data were used to generate spin-echo images for various echo times and repetition times (TRs). A new method-"pulse sequence extrapolation" -synthesizes images for pulse sequences different from that of the acquisition. MSE data acquired in a time equivalent to a TR of 2,000 msec can be used to generate inversion-recovery (IR) images for arbitrarily chosen TI inversion times. Other combinations of pulse sequences were also studied, and synthetic images were compared visually and quantitatively to directly acquired images with corresponding parameters. Synthetic IR signals of the brain parenchyma consistently matched directly acquired signals to within 6%, with respect to the full magnetization signal. The noise level of synthetic signals was generally no more than twice that of direct acquisition signals, as predicted. This method can achieve selective fat suppression and enhancement in IR imaging. 相似文献
995.
A Oberstein G Zocholl W Schmied 《R?ntgen-Bl?tter; Zeitschrift für R?ntgen-Technik und medizinisch-wissenschaftliche Photographie》1990,43(12):536-538
Patients suffering from "coral reef arteriosclerosis" are presented, the lesions being visualised via CT and angiography. This disease is characterised by an almost complete occlusion of the median ventricular aorta due to extreme, irregularly structured calcareous masses in the vascular lumen. The review of the literature points to the possible aetiology and pathogenesis of this disease pattern. 相似文献
996.
RB Johanson SA Spencer P Rolfe P Jones DS Malla 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(11):859-863
A prospective observational study of post-delivery care and neonatal body temperature, carried out at Kathmandu Maternity Hospital, was followed by a randomized controlled intervention study using three simple methods for maintaining body temperature. There were 500 infants in the initial observation study and 300 in the intervention study. In the observation study, 85% (420/495) of infants had temperatures < 36 degrees C at 2 h and nearly 50% (198/405) had temperatures < 36 degrees C at 24 h (14% were < 35 degrees C). Most of the infants who were cold at 24 h had initially become cold at the time of delivery (only seven infants had been both well dried and wrapped). In the intervention study, all infants were dried and wrapped before random assignment to one of the three methods: the "kangaroo" method, the traditional "oil massage" or a "plastic swaddler". All three were found to be equally effective. Overall, 38% (114/298) of the infants had temperatures < 36 degrees C at 2 h and 18% (41/231) at 24 h (when none was < 35 degrees C). 相似文献
997.
998.
999.
Effects of tumor necrosis factor and lymphotoxin on peripheral lymphoid tissue development 总被引:1,自引:0,他引:1
Ettinger R; Mebius R; Browning JL; Michie SA; van Tuijl S; Kraal G; van Ewijk W; McDevitt HO 《International immunology》1998,10(6):727-741
Previously, we have reported that neutralization of surface lymphotoxin
(LT-alphabeta) in mice which expressed an LT-beta receptor-Fc fusion
protein, driven by the cytomegalovirus promoter, resulted in an array of
anatomic abnormalities. We now report that mice which express a tumor
necrosis factor (TNF) receptor p60-Fc fusion protein (which neutralizes TNF
and soluble LT-alpha3 activity) develop unique lymphoid abnormalities. Our
data demonstrate that some aspects of peripheral lymphoid organ development
require both surface LT-alphabeta and TNF interacting with their specific
receptors. However, these related cytokines are also capable of signaling
distinct developmental events. Splenic MAdCAM-1 expression, follicular
dendritic cell localization and normal Peyer's patch development all
require both surface LT-alphabeta and TNF activity. Marginal zone formation
and splenic B cell localization primarily require surface
LT-alphabeta-LT-beta receptor interactions. Primary follicle formation was
dependent upon TNF receptor(s) engagement. Interestingly spleen, lymph
nodes and Peyer's patches from TNF receptor p60-Fc-expressing mice all
develop different abnormalities, suggesting distinct pathways of
development in these lymphoid organs. Thymus development appears to be
independent of these signaling pathways. These results demonstrate that TNF
and LT are crucial for normal peripheral, but not central lymphoid organ
development.
相似文献
1000.
A high frequency African coding polymorphism in the N-terminal domain of ICAM-1 predisposing to cerebral malaria in Kenya 总被引:15,自引:2,他引:15
Fernandez-Reyes D; Craig AG; Kyes SA; Peshu N; Snow RW; Berendt AR; Marsh K; Newbold CI 《Human molecular genetics》1997,6(8):1357-1360
The malarial parasite Plasmodium falciparum has acted as a potent selective
force on the human genome. The particular virulence of this organism is
thought to be due to the adherence of parasitised red blood cells to small
vessel endothelium through several receptors, including CD36,
thrombospondin and intercellular adhesion molecule 1 (ICAM-1, CD54), and
parasite isolates differ in their ability to bind to each.
Immunohistochemical studies have implicated ICAM-1 as of potential
importance in the pathogenesis of cerebral malaria, leading us to reason
that if any single receptor were involved in the development of cerebral
malaria, then in view of the high mortality of that complication, natural
selection should have produced variants with reduced binding capacity. We
therefore sequenced the N-terminal domain of ICAM-1 from a number of
Africans and discovered a single mutation present at high frequency.
Genotypes at this locus from samples from a case-control study indicated an
association of the polymorphism with the severity of clinical malaria such
that individuals homozygous for the mutation have increased susceptibility
to cerebral malaria with a relative risk of two. These counterintuitive
results have implications for the mechanism of malaria pathogenesis,
resistance to other infectious agents and transplantation immunology.
相似文献