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101.
The search for better surgical repair of nerve injuries should be aimed at uncovering alternatives that not only are efficient, but also enhance nerve growth. The purpose of this study was to compare functional nerve responses following repair with either a traditional microsuture technique or Quixil human fibrin sealant. Thirty female Lewis rats received transection of the right sciatic nerve. Nerve repair was achieved with either epineurial microsuture (n = 15) or Quixil fibrin glue (n = 15). Functional results were assessed at 2, 6, and 12 weeks postoperatively with walking-track analysis. Electrophysiologic nerve recordings were also performed 12 weeks postoperatively. Rats receiving Quixil nerve repair returned to baseline performance on the walking-track analysis significantly faster than those with microsuture repairs (6 and 12 weeks postoperatively; p < 0.0001). Recovery of nerve conduction velocities and wave amplitudes was also significantly better in the nerves repaired with Quixil than in those repaired with microsuture (p's < 0.0001). Quixil human fibrin sealant is a good alternative to traditional microsuture nerve repair techniques.  相似文献   
102.

Aims

To assess the effects of a Pilates exercise program compared to conventional pelvic floor muscle training (PFMT) protocol on pelvic floor muscle strength (PFMS) in patients with post‐prostatectomy urinary incontinence.

Methods

Patients were randomized into three treatment groups (G1: Pilates, G2: electrical stimulation combined with PFMT, and G3: control group). Duration of therapy was 10 weeks. Baseline assessment included the 24 h pad‐test and the ICI‐Q questionnaire. PFMS was measured using a manometric perineometry device at baseline and 4 months after radical prostatectomy (RP). The level of significance was P < 0.05.

Results

One hundred twenty three patients were randomized and 104 patients completed the study protocol (G1: n = 34; G2: n = 35; G3: n = 35). Post‐treatment assessment showed statistically significant improvements in maximum strength in G2, increased endurance in G1 and G2, and increment of muscle power in all three groups (P < 0.05). However, there were no significant differences in the mean changes of maximum strength, endurance, and muscle power between groups after treatment (P > 0.05). G1 and G2 achieved a higher number of fully continent patients than G3 (P < 0.05). At the end of treatment, 59% of patients in G1, 54% in G2, and 26% in G3 were continent (no pads/day).

Conclusions

Improvements in PFMS parameters were distinct among active treatment groups versus controls, but did not predict recovery of urinary continence at final assessment. The Pilates method promoted similar outcomes in the proportion of fully continent patients when compared to conventional PFMT 4 months after RP.  相似文献   
103.
104.

Purpose

To compare the diagnostic accuracy of iodine quantification and standard enhancement measurements in distinguishing enhancing from nonenhancing renal masses.

Materials and methods

The Institutional Review Board approved this retrospective study conducted from data found in institutional patient databases and archives. Seventy-two renal masses were characterised as enhancing or nonenhancing using standard enhancement measurements (in HU) and iodine quantification (in mg/ml). Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of standard enhancement measurements and iodine quantification were calculated from χ 2 tests of contingency with histopathology or imaging follow-up as the reference standard. Difference in accuracy was assessed by means of McNemar analysis.

Results

Sensitivity, specificity, PPV, NPV and diagnostic accuracy for standard enhancement measurements and iodine quantification were 77.7 %, 100 %, 100 %, 81.8 %, 89 % and 100 %, 94.4 %, 94.7, 100 % and 97 %, respectively. The McNemar analysis showed that the accuracy of iodine quantification was significantly better (P?<?0.001) than that of standard enhancement measurements.

Conclusion

Compared with standard enhancement measurements, whole-tumour iodine quantification is more accurate in distinguishing enhancing from nonenhancing renal masses.

Key Points

? Enhancement of renal lesions is important when differentiating benign from malignant tumours. ? Dual-energy CT offers measurement of iodine uptake rather than mere enhancement values. ? Whole-tumour iodine quantification seems more accurate than standard CT enhancement measurements.  相似文献   
105.
The early endosomes constitute a major sorting platform in eukaryotic cells. They receive material through fusion with endocytotic vesicles or with trafficking vesicles from the Golgi complex and later sort it into budding vesicles. While endosomal fusion is well understood, sorting is less characterized; the 2 processes are generally thought to be effected by different, unrelated machineries. We developed here a cell-free assay for sorting/budding from early endosomes, by taking advantage of their ability to segregate different cargoes (such as transferrin, cholera toxin subunit B, and low-density lipoprotein, LDL) into different carrier vesicles. Cargo separation required both carrier vesicle formation and active maturation of the endosomes. Sorting and budding were insensitive to reagents perturbing clathrin coats, coatomer protein complex-I (COPI) coats, dynamin, and actin, but were inhibited by anti-retromer subunit antibodies. In addition, the process required Rab-GTPases, phosphatidylinositol-3-phosphate, and, surprisingly, the docking factor early endosomal autoantigen 1 (EEA1). Sorting also required the function of the N-ethylmaleimide-sensitive factor (NSF), a well-known fusion cofactor, while it did not depend on preceding fusion of endosomes. We conclude that fusion, docking, and sorting/budding are interconnected at the molecular level.  相似文献   
106.
Optical coherence tomography is a novel imaging technique providing high-resolution bidimensional images of tissue microstructures. Several studies have been published on the use of this technique in different fields of medicine, particularly ophthalmology. There are very few studies in the field of otolaryngology. This paper presents various applications of optical coherence tomography in the different sub-specialties of otolaryngology, as well as the benefits of this technique over traditional diagnostic methods.  相似文献   
107.

Introduction  

Resuscitation goals for septic shock remain controversial. Despite the normalization of systemic hemodynamic variables, tissue hypoperfusion can still persist. Indeed, lactate or oxygen venous saturation may be difficult to interpret. Our hypothesis was that a gastric intramucosal pH-guided resuscitation protocol might improve the outcome of septic shock compared with a standard approach aimed at normalizing systemic parameters such as cardiac index (CI).  相似文献   
108.
The phase I biotransformation of combretastatin A-4 (CA-4) 1, a potent tubulin polymerization inhibitor with antivascular and antitumoral properties, was studied using rat and human liver subcellular fractions. The metabolites were separated by high-performance liquid chromatography and detected with simultaneous UV and electrospray ionization (ESI) mass spectrometry. The assignment of metabolite structures was based on ESI-tandem mass spectrometry experiments, and it was confirmed by comparison with reference samples obtained by synthesis. O-Demethylation and aromatic hydroxylation are the two major phase I biotransformation pathways, the latter being regioselective for phenyl ring B of 1. Indeed, incubation with rat and human microsomal fractions led to the formation of a number of metabolites, eight of which were identified. The regioselectivity of microsomal oxidation was also demonstrated by the lack of metabolites arising from stilbenic double bond epoxidation. Alongside the oxidative metabolism, Z-E isomerization during in vitro study was also observed, contributing to the complexity of the metabolite pattern. Moreover, when 1 was incubated with a cytosolic fraction, metabolites were not observed. Aromatic hydroxylation at the C-6' of phenyl ring B and isomerization led to the formation of M1 and M2 metabolites, which were further oxidized to the corresponding para-quinone (M7 and M8) species whose role in pharmacodynamic activity is unknown. Metabolites M4 and M5, arising from O-demethylation of phenyl ring B, did not form the ortho-quinones. O-Demethylation of phenyl ring A formed the metabolite M3 with a complete isomerization of the stilbenic double bond.  相似文献   
109.
Studying B16-F10 cells we could identify β-1 integrins as laminin, fibronectin and collagen receptors. Gradient ionic strength elution analysis of affinity chromatography showed differential interactions between laminin-binding β-1 integrins (two β-1 polypeptides of 105 and 120 kDa) and fibronectin and collagen-binding β-1 integrins (elution of one major β-1 polypeptide of 120 kDa) and their respective ligands. To evaluate this diversity we submitted B16-F10 extracts to IEF and SDS-PAGE and found that one β-1 integrin formed acidic and larger isoforms, while another formed basic and smaller isoforms. To study this difference we also submitted material eluted from WGA-Sepharose columns to IEF but now only the acidic β-1 isoform was found. Extracts of B16-F10 treated with neuraminidase showed only the basic β-1 isoform, suggesting that terminal sialic acid residues may be responsible for this acidic pattern, an interpretation supported by the fact that MAA (Maackia ammurensis agglutinin) reacts only with the acidic isoform. Differential glycosylation of β-1 integrin isoforms in B16-F10 was also demonstrated since the smaller lamininbinding β-1 integrin isoform reacted only with GNA (Galanthus nivalis agglutinin), whereas the mature larger form reacted with DSA (Datura stramonium agglutinin) and MAA; thus this heterogeneity of β-1 chains is essentially due to variable glycosylation. Autoradiography and immunoblotting analysis of material separated by 2-dimensional electrophoresis show that only the processed forms of β-1 integrins are expressed at the cell surface. © 1995 Wiley Liss, Inc.  相似文献   
110.
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