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1.
Fragestellung: Die Karzinomassoziierte Retinopathie (CAR) stellt ein seltenes paraneoplastisches Syndrom dar, das bislang am h?ufigsten bei kleinzelligen Bronchialkarzinomen beschrieben wurde. Wir berichten über 3 Patientinnen mit CAR in Gegenwart eines Mammakarzinoms bzw. eines Karzinoids der Cervix uteri. Patienten und Methode: Es wurden biomikroskopische, perimetrische, angiographische und elektrophysiologische Befunde erhoben. Au?erdem erfolgte eine Testung der Immunreaktivit?t der Seren an humaner Retina. Ergebnisse: Die Befunde umfa?ten ringf?rmige Gesichtsfelddefekte mit statokinetischer Dissoziation und eine pathologische St?bchen- und Zapfenantwort im ERG. Bei 1 Patientin wurde immunhistochemisch eine Reaktion im Bereich der Photorezeptorinnensegmente, der ?u?eren K?rnerschicht sowie der ?u?eren plexiformen Schicht bei fehlendem Nachweis von Antik?rpern gegen Recoverin gefunden. Diskussion: Neben dem kleinzelligen Bronchialkarzinom k?nnen auch andere Prim?rtumoren mit einer CAR vergesellschaftet sein. Der Nachweis von retinalen Autoantik?rpern unterstützt die Annahme einer tumorinduzierten Immunantwort aufgrund der Expression identischer Epitope durch die Tumorzellen. Dabei kommen offensichtlich verschiedene retinale Proteine als Autoantigene in Betracht.   相似文献   
2.
We have previously shown that the human thyroglobulin (hTg) 20-mer peptide p2340 (aa 2340-2359) contains an epitope recognized by Tg-reactive B cells in patients with Graves' disease. The presence of several Ek-binding motifs within p2340 prompted us to examine whether this peptide can stimulate a T-cell response and elicit experimental autoimmune thyroiditis (EAT) in AKR/J (H-2k) mice. The peptide was found to be immunogenic at the T-cell level since it induced specific proliferative responses as well as interleukin-2 and interferon-gamma secretion in secondary cultures of peptide-primed lymph node cells (LNC). The p2340-specific proliferation was blocked almost completely by an Ek-specific monoclonal antibody (mAb) but was unaffected by a control Ak-specific mAb. Peptide-primed LNC did not respond to intact hTg and conversely, LNC primed in vivo with hTg did not respond to p2340 in culture, suggesting that p2340 contains non-dominant T-cell epitope(s). Direct subcutanaeous challenge of AKR/J mice (n = 9) with p2340 in adjuvant, elicited mild to moderate EAT (infiltration index of 1-2) and strong p2340-specific immunoglobulin G responses in all mice tested. These data delineate a new thyroiditogenic sequence within the carboxyl terminal region of hTg.  相似文献   
3.
Summary Resistance to teniposide (VM-26) by VM-26 selected resistant L1210 cells in culture was attributed to alterations in the flux of VM-26 across the plasma membrane and to functions of homogeneously staining regions that appeared on one or more chromosomes. In the present study, electrophoresis of membrane-cytosol fractions of these resistant sublines demonstrated a protein band, Mr 22 kd, that was not evident in similar fractions of drugsensitive L1210 cells or three revertant sublines. The distribution of this protein among various cellular fractions could be altered by manipulation of the concentration of calcium ions. A representative subline, LIa5 M, was observed to have vesicles that reacted with Sudan black B stain, an indication of altered lipid metabolism. The LIa5 M subline was cross-resistant to etoposide, vincristine, doxorubicin, amsacrine, and actinomycin D. Concentrations of VM-26 that inhibited cell division to the same extent caused an accumulation of fewer cells in the G2 stage of cell division in LIa5 M cultures than in L1210 cultures. These observations indicate that the LIa5 M subline expressed multiple drug resistance, as well as changes in the expression of cytotoxicity to VM-26.This investigation was supported by Research Project Grant CA 35319, by Cancer Center Support (CORE) Grant CA 21765 from the National Cancer Institute, and by the American Lebanese Syrian Associated Charities.Recipient of research support from a training grant, American Cancer Society Grant IN-85-06, to the University of Tennessee Center for the Health Sciences  相似文献   
4.
Background: The prompt identification of patients with poor prognosis is essential in order to improve the treatment outcomes in prostate cancer (CaP); as a novel approach, several molecular markers, including integrins, have been discussed as prognostic biomarkers. Our aim was to comprehensively examine aberrant expression of integrins in correlation with clinicopathological features and prognosis in CaP by synthesizing all available evidence, in a systematic review and meta-analysis. Methods: A systematic review and meta-analysis was performed in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines. Scientific literature databases (Pubmed, Embase, and Scopus) were systematically searched until May 10, 2020. Random-effects (DerSimonian-Laird) models were used to estimate pooled odds ratios (ORs) for cross-sectional correlations with clinicopathological characteristics and relative risks for longitudinal associations with prognosis. Results: Fourteen studies were included with a total number of 3,194 CaP cases examined (13 cross-sectional and four longitudinal cohort study arms). Correlation of low expression of α6 (pooled OR = 0.10, 95% confidence interval [CI]: 0.04–0.28, P < 0.001) and β1 (pooled OR = 0.45; 95% CI: 0.21–1.00, P = 0.049) integrin with high Gleason score was noted. A borderline trend between reduced expression of α6 integrin and an advanced clinical stage of CaP (pooled OR = 0.48; 95% CI: 0.22-1.03, P = 0.06) was observed. No associations with biochemical recurrence and survival were documented. Conclusions: Evidence on the association of low expression of integrins α6 and β1 and more advanced CaP exist, whereas significant results on survival were not documented; further studies are warranted.  相似文献   
5.
Coronavirus disease 2019 (COVID-19) is associated with poor cardiovascular outcomes in patients with heart failure (HF) of all categories of ejection fraction (EF), but mainly in patients with HF with reduced EF. Moreover, cardiac transplant patients exhibit worse cardiovascular prognosis, high mortality, and more admissions to the intensive care unit. In general, COVID-19 seems to de-teriorate the clinical status of HF and favors the development of acute respiratory distress syndrome and multiorgan failure, especially in the presence of cardiovascular comorbidities such as diabetes mellitus, kidney dysfunction, and older age. COVID-19 may induce new-onset HF with complex mechanisms that involve myocardial injury. Indeed, myocardial injury comprises a large category of detrimental effects for the myocardium, such as myocardial infarction type 1 or type 2, Takotsubo cardiomyopathy, microvascular dysfunction and myocarditis, which are not easily distinguished by HF. The pathophysiologic mechanisms mainly involve direct myocardial damage by severe acute respiratory syndrome coronavirus 2, cytokine storm, hypercoagulation, inflammation, and endothelial dysfunction. The proper management of patients with COVID-19 involves careful patient evaluation and ongoing monitoring for complications such as HF.  相似文献   
6.
7.
In the current work, a novel complex concentrated aluminum alloy is designed and studied. In order to investigate the unknown region of the multicomponent phase diagrams, thermo-physical parameters and the CALPHAD method were used to understand the phase formation of the Al58Mg18Zn12Cu5Si7 at.% (Al47.4Mg13.3Zn23.8Cu9.6Si6wt.%) alloy with a low-density of 2.63 g/cm3. The CALPHAD methodology showed good agreement with both the investigated microstructure and the thermodynamic parameters. The designed alloy was manufactured using an induction furnace and pour mold casting process. This study avoids the use of expensive, dangerous or scarce alloying elements and focuses instead on the utilization of widely available relatively cheaper elements. The microstructural evolution as a function of the heat-treatment was studied by means of different microstructural characterization techniques. The hardness, compressive strength and electrical conductivity of the as-cast and heat-treated alloy at room temperature were studied and correlated with the previously characterized microstructure. The alloy is characterized by a multiphase microstructure with major α-Al matrix reinforced with various secondary phases. In terms of mechanical properties, the developed alloy exhibited a high hardness value of 249 Vickers and compressive strength of 588 MPa. The present work provides a valuable insight for researchers, who aim to design and produce industry-like Aluminum based complex concentrated alloys (CCAs).  相似文献   
8.
Rizos E  Liamis G  Elisaf M 《Nephron》2002,91(2):339-340
The syndrome of inappropriate ADH secretion (SIADH) is a common cause of hyponatremia. However, other metabolic abnormalities have infrequently been described in patients with the syndrome of inappropriate antidiuresis. Here, we describe a female patient with hyponatremia due to SIADH who presented with a cluster of metabolic abnormalities and specifically hypouricemia associated with uricosuria, hypokalemia caused by renal potassium wasting, hypomagnesemia with inappropriate magnesiuria, hypophosphatemia with renal phosphate wasting and inappropriate calciuria. These abnormalities could be partly due to the extracellular volume expansion and were corrected with the water restriction-induced increase in serum sodium levels.  相似文献   
9.
Total versus selective hepatic vascular exclusion in major liver resections   总被引:34,自引:0,他引:34  
BACKGROUND: Total hepatic vascular exclusion (THVE) and selective hepatic vascular exclusion (SHVE) are two effective techniques for bleeding control in major hepatic resections. Outcomes of the two procedures were compared. METHODS: Patients undergoing major liver resection were randomly allocated to the THVE and SHVE groups. Intraoperative hemodynamic changes and the postoperative course of the two groups were compared. RESULTS: During vascular clamping, the THVE group showed a significant elevation in pulmonary vascular resistance, systemic vascular resistance, intrapulmonary shunts, and a significant reduction in cardiac index, compared with the SHVE group (P <0.05). Patients undergoing THVE received more crystalloids and blood, showed more severe liver, renal and pancreatic dysfunction, and had a longer hospital stay than the SHVE group (P <0.05). CONCLUSIONS: Both techniques are equally effective in bleeding control in major liver resections. THVE is associated with cardiorespiratory and hemodynamic alterations and may be not tolerated by some patients. SHVE is well tolerated with fewer postoperative complications and shorter hospitalization time.  相似文献   
10.
Study Type – Therapy (case series) Level of Evidence 4 What’s known on the subject? and What does the study add? The use of robotic arms for instrument and camera manipulation has been proposed for more than a decade. The current study provides a direct comparison of robotic camera movement to the conventional human camera holding assistance in real operative room setting.

OBJECTIVE

? To assess, in a prospective randomized study, the efficiency of the FreeHand® (Prosurgics Ltd, Bracknell, UK) compared to manual camera control during the performance of endoscopic extraperitoneal radical prostatectomy (EERPE).

PATIENTS AND METHODS

? Three surgeons performed 50 EERPE for localized prostate cancer. In group A (n= 25), procedures were performed with manual control of the camera by the assistant, whereas group B (n= 25) patients were treated with the assistance of the FreeHand® robotic device. ? The EERPE procedure was divided into several steps. ? Total operation duration, time for each surgical step, number of camera movements, number of movement errors, number of times the lens was cleaned, blood loss and margin status were compared.

RESULTS

? No statistically significant difference was observed in terms of patient age, preoperative prostate‐specific antigen level, Gleason score, positive cores and prostate volume. ? The average operation duration required for the performance of each step did not differ significantly between the two groups. ? Significant differences in favour of the FreeHand® camera holder were observed in case of horizontal and zooming camera movement, camera cleaning and camera errors. ? Vertical camera movements were performed significantly faster by the human assistant compared to the robotic camera holder. ? The average total operation duration was similar for both groups. ? Positive surgical margins were detected in one patient in each group (4% of the patients).

CONCLUSIONS

? A comparison of the FreeHand® robotic camera holder with human camera control during EERPE showed a similar time requirement for the performance of each step of the procedure. ? The robotic system provided accurate and fast movements of the camera without compromising the outcome of the procedure.  相似文献   
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