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991.

Introduction

Laparoscopic Heller-Dor surgery is the current treatment of choice for patients with esophageal achalasia, but elderly patients are generally referred for less invasive treatments (pneumatic dilations or botulinum toxin injections).

Aim

To assess the effect of age on the surgical outcome of patients receiving laparoscopic Heller-Dor as primary treatment.

Methods

Demographic and clinical findings were prospectively collected on patients undergoing laparoscopic Heller-Dor from 1992 to 2012. Patients were classified in three age brackets: group A (≤45 years), group B (45–70), and group C (≥70). Treatment was defined as a failure if the postoperative symptom score was >10th percentile of the preoperative score (i.e., >8). We consecutively performed the Heller-Dor in 571 achalasia patients, 305 (53.4 %) in group A, 226 (39.6 %) in group B, and 40 (7 %) in group C.

Results

The mortality was nil; the conversion and morbidity rates were both 1.1 %. Group C patients had higher preoperative symptom scores (p?=?0.02), while the symptom duration was similar in all three groups. Mucosal tears occurred in 17 patients (3 %): 6 (2 %) in group A, 8 (3.5 %) in group B, and 3 (7.5 %) in group C (p?=?0.09). The postoperative hospital stay was slightly longer for group C (p?=?0.06).

Discussion

The treatment failure rate was quite similar: 31 failures in group A (10.1 %), 19 in group B (8.4 %), and 3 in group C (7.5 %; p?=?0.80). These failures were seen more in manometric pattern III (22.2 %, p?=?0.002). Laparoscopic Heller-Dor can be used as the first therapeutic approach to achalasia even in elderly patients with an acceptable surgical risk.  相似文献   
992.
993.
Synthetic ligament for anterior cruciate ligament (ACL) reconstruction has been widely used in the past. Long-term follow-up has demonstrated the unreliability of many of these devices in ACL surgery, and problems may arise for the surgeon approaching a patient with failed artificial ligament reconstruction. The aim of this study is to investigate whether revision surgery may improve clinical and radiographic outcomes in patients with failed synthetic ACL reconstruction. Fourteen patients who were treated in the past with ACL reconstruction with synthetic grafts underwent two-stage revision surgery. Follow-up averaged 4.2 years (range 2–6 years). Mean KOOS score was 75.8 (SD 10.2); IKDC score was B in two patients, C in nine and D in three. The improvement compared to preoperative status was not statistically significant (p > 0.05). Four patients were positive to Lachman and anterior drawer tests. Mean side-to-side anterior laxity averaged 4.3 mm (SD 1.2). Biopsy specimens documented the presence of foreign body granulomatous reaction, giant foreign body cells and polyethylene wear particles. The level of osteoarthritis worsened at follow-up compared to preoperative status (p < 0.05). ACL revision surgery with autografts in patients who underwent previous failed primary synthetic ligament reconstruction does not improve clinical outcomes and does not influence the natural history of knee osteoarthritis started from artificial ligament debris.  相似文献   
994.
The β-blockers carvedilol and metoprolol provide important therapeutic strategies for heart failure treatment. Therapy with metoprolol facilitates the control by phosphodiesterase PDE3, but not PDE4, of inotropic effects of catecholamines in human failing ventricle. However, it is not known whether carvedilol has the same effect. We investigated whether the PDE3-selective inhibitor cilostamide (0.3 μM) or PDE4-selective inhibitor rolipram (1 μM) modified the positive inotropic and lusitropic effects of catecholamines in ventricular myocardium of heart failure patients treated with carvedilol. Right ventricular trabeculae from explanted hearts of nine carvedilol-treated patients with terminal heart failure were paced to contract at 1 Hz. The effects of (-)-noradrenaline, mediated through β1-adrenoceptors (β2-adrenoceptors blocked with ICI118551), and (-)-adrenaline, mediated through β2-adrenoceptors (β1-adrenoceptors blocked with CGP20712A), were assessed in the absence and presence of the PDE inhibitors. The inotropic potency, estimated from –logEC50s, was unchanged for (-)-noradrenaline but decreased 16-fold for (-)-adrenaline in carvedilol-treated compared to non-β-blocker-treated patients, consistent with the previously reported β2-adrenoceptor-selectivity of carvedilol. Cilostamide caused 2- to 3-fold and 10- to 35-fold potentiations of the inotropic and lusitropic effects of (-)-noradrenaline and (-)-adrenaline, respectively, in trabeculae from carvedilol-treated patients. Rolipram did not affect the inotropic and lusitropic potencies of (-)-noradrenaline or (-)-adrenaline. Treatment of heart failure patients with carvedilol induces PDE3 to selectively control the positive inotropic and lusitropic effects mediated through ventricular β2-adrenoceptors compared to β1-adrenoceptors. The β2-adrenoceptor-selectivity of carvedilol may provide protection against β2-adrenoceptor-mediated ventricular overstimulation in PDE3 inhibitor-treated patients. PDE4 does not control β1- and β2-adrenoceptor-mediated inotropic and lusitropic effects in carvedilol-treated patients.  相似文献   
995.
996.
The beneficial effects of beetroot juice supplementation (BJS) have been tested during cycling, walking, and running. The purpose of the present study was to investigate whether BJS can also improve performance in swimmers. Fourteen moderately trained male master swimmers were recruited and underwent two incremental swimming tests randomly assigned in a pool during which workload, oxygen uptake (VO2), carbon dioxide production (VCO2), pulmonary ventilation (VE), and aerobic energy cost (AEC) of swimming were measured. One was a control swimming test (CSW) and the other a swimming test after six days of BJS (0.5l/day organic beetroot juice containing about 5.5 mmol of NO3). Results show that workload at anaerobic threshold was significantly increased by BJS as compared to the CSW test (6.3 ± 1 and 6.7 ± 1.1 kg during the CSW and the BJS test respectively). Moreover, AEC was significantly reduced during the BJS test (1.9 ± 0.5 during the SW test vs. 1.7 ± 0.3 kcal·kg−1·h−1 during the BJS test). The other variables lacked a statistically significant effect with BJS. The present investigation provides evidence that BJS positively affects performance of swimmers as it reduces the AEC and increases the workload at anaerobic threshold.  相似文献   
997.
998.
It is well known that fabrication processes inevitably lead to defects in the manufactured components. However, thanks to the new capabilities of the manufacturing procedures that have emerged during the last decades, the number of imperfections has diminished while numerical models can describe the ground truth designs. Even so, a variety of defects has not been studied yet, let alone the coupling among them. This paper aims to characterise the buckling response of Variable Stiffness Composite (VSC) plates subjected to spatially varying fibre volume content as well as fibre misalignments, yielding a multiscale sensitivity analysis. On the one hand, VSCs have been modelled by means of the Carrera Unified Formulation (CUF) and a layer-wise (LW) approach, with which independent stochastic fields can be assigned to each composite layer. On the other hand, microscale analysis has been performed by employing CUF-based Mechanics of Structure Genome (MSG), which was used to build surrogate models that relate the fibre volume fraction and the material elastic properties. Then, stochastic buckling analyses were carried out following a multiscale Monte Carlo analysis to characterise the buckling load distributions statistically. Eventually, it was demonstrated that this multiscale sensitivity approach can be accelerated by an adequate usage of sampling techniques and surrogate models such as Polynomial Chaos Expansion (PCE). Finally, it has been shown that sensitivity is greatly affected by nominal fibre orientation and the multiscale uncertainty features.  相似文献   
999.
1000.
Purpose

Pasireotide is an effective treatment for acromegaly and Cushing’s disease, although treatment-emergent hyperglycemia can occur. The objective of this study was to assess incretin-based therapy versus insulin for managing pasireotide-associated hyperglycemia uncontrolled by metformin/other permitted oral antidiabetic drugs.

Methods

Multicenter, randomized, open-label, Phase IV study comprising a core phase (≤?16-week pre-randomization period followed by 16-week randomized treatment period) and optional extension (ClinicalTrials.gov ID: NCT02060383). Adults with acromegaly (n?=?190) or Cushing’s disease (n?=?59) received long-acting (starting 40 mg IM/28 days) or subcutaneous pasireotide (starting 600 µg bid), respectively. Patients with increased fasting plasma glucose (≥?126 mg/dL on three consecutive days) during the 16-week pre-randomization period despite metformin/other oral antidiabetic drugs were randomized 1:1 to open-label incretin-based therapy (sitagliptin followed by liraglutide) or insulin for another 16 weeks. The primary objective was to evaluate the difference in mean change in HbA1c from randomization to end of core phase between incretin-based therapy and insulin treatment arms.

Results

Eighty-one (32.5%) patients were randomized to incretin-based therapy (n?=?38 received sitagliptin, n?=?28 subsequently switched to liraglutide; n?=?12 received insulin as rescue therapy) or insulin (n?=?43). Adjusted mean change in HbA1c between treatment arms was – 0.28% (95% CI – 0.63, 0.08) in favor of incretin-based therapy. The most common AE other than hyperglycemia was diarrhea (incretin-based therapy, 28.9%; insulin, 30.2%). Forty-six (18.5%) patients were managed on metformin (n?=?43)/other OAD (n?=?3), 103 (41.4%) patients did not require any oral antidiabetic drugs and 19 patients (7.6%) were receiving insulin at baseline and were not randomized.

Conclusion

Many patients receiving pasireotide do not develop hyperglycemia requiring oral antidiabetic drugs. Metformin is an effective initial treatment, followed by incretin-based therapy if needed.

ClinicalTrials.gov ID: NCT02060383.

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