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101.
Parkinson's disease (PD) is caused by dopamine (DA) depletion consequent to cell degeneration in the substantia nigra pars compacta (SNc) and the ventral tegmental area (VTA). Although computational analyses of PD have focused on DA depletion in DA-recipient parts of the basal ganglia, there is also extensive DAergic innervation of the frontal and parietal cortex as well as the spinal cord. To understand PD bradykinesia, a comprehensive network model is needed to study how patterns of DA depletion at key cellular sites in the basal ganglia, cortex and spinal cord contribute to disordered neuronal and spinal cord activity and other PD symptoms. We extend a basal ganglia-cortico-spinal circuit for control of voluntary arm movements by incorporating DAergic innervation of cells in the cortical and spinal components of the circuit. The resultant model simulates successfully several of the main reported effects of DA depletion on neuronal, electromyographic (EMG), and movement parameters of PD bradykinesia.  相似文献   
102.
An unusual case of lipid embolization to brain and kidney after lymphography in a patient with non-Hodgkin lymphoma of the upper anterior mediastinum is reported. Contrast material-enhanced echocardiography demonstrated a right-to-left shunt to the left atrium without evidence of a patent foramen ovale. Echo contrast particles were transiently present within the tumor surrounding the great vessels.  相似文献   
103.
Despite advances in surgical technique, rotator cuff repairs are plagued by a high rate of failure. This failure rate is in part due to poor tendon‐to‐bone healing; rather than regeneration of a fibrocartilaginous attachment, the repair is filled with disorganized fibrovascular (scar) tissue. Transforming growth factor beta 3 (TGF‐β3) has been implicated in fetal development and scarless fetal healing and, thus, exogenous addition of TGF‐β3 may enhance tendon‐to‐bone healing. We hypothesized that: TGF‐β3 could be released in a controlled manner using a heparin/fibrin‐based delivery system (HBDS); and delivery of TGF‐β3 at the healing tendon‐to‐bone insertion would lead to improvements in biomechanical properties compared to untreated controls. After demonstrating that the release kinetics of TGF‐β3 could be controlled using a HBDS in vitro, matrices were incorporated at the repaired supraspinatus tendon‐to‐bone insertions of rats. Animals were sacrificed at 14–56 days. Repaired insertions were assessed using histology (for inflammation, vascularity, and cell proliferation) and biomechanics (for structural and mechanical properties). TGF‐β3 treatment in vivo accelerated the healing process, with increases in inflammation, cellularity, vascularity, and cell proliferation at the early timepoints. Moreover, sustained delivery of TGF‐β3 to the healing tendon‐to‐bone insertion led to significant improvements in structural properties at 28 days and in material properties at 56 days compared to controls. We concluded that TGF‐β3 delivered at a sustained rate using a HBDS enhanced tendon‐to‐bone healing in a rat model. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1099–1105, 2011  相似文献   
104.
The aim of the study is to determine whether dermal scarification is equally effective for treating acute renal colic compared to diclofenac sodium intramuscular therapy. A prospective, randomized controlled study was conducted with methodologic rigor based on CONSORT criteria. A total of 291 patients, aged ≥18 years, suffering from acute renal colic were included in this trial and randomly assigned in two groups. Patients in the first group (A) received endodermal injection (dermal scarification) of 1 ml normal saline at the area of intensity of pain. The second group (B) received 75 mg diclofenac sodium by intramuscular injection. The success of each method defined the primary end point. Pain intensity before and after treatment was assessed using a visual analog scale. The time onset and the duration of analgesia were also recorded. There was no significant difference between the two groups regarding hematuria (p = 0.158), stone identification at KUB (p = 0.751) and mean pain intensity (p = 0.609) before treatment initiation. The method was successful in 75.5 % of patients in group A and 74.3 % of patients in group B (p = 0.812). Mean pain reduction was comparable, 5.65 ± 3.05 in group A and 5.34 ± 2.99 in group B (p = 0.379), with dermal scarification eliciting its effect considerably faster, whereas the duration of analgesia was longer in the diclofenac group (p < 0.05). In conclusion, dermal scarification could constitute an alternative method for treating renal colic as it is equally effective compared to the standard treatment of diclofenac sodium.  相似文献   
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107.

Introduction and hypothesis

The causal association between pelvic organ prolapse (POP) and overactive bladder (OAB) symptoms is supported by several theories. The aim of this study is to assess any changes in OAB symptoms among women with POP and OAB after successful pessary placement.

Methods

During the study period, all women with symptomatic POP stage II or greater and OAB symptoms were offered the solution of either a ring or a Gellhorn pessary. All patients were asked to complete a 3-day micturition/incontinence diary. Objective evaluation endpoints at baseline and at 6 weeks included: change in the mean number of micturitions/24 h, change in the mean volume voided per micturition/24 h, and change in the number of urinary incontinence episodes. Subjective evaluation of the urgency, frequency, and nocturia symptoms was carried out using the score change of the questions 3, 5, and 2 of the International Consultation on Incontinence Questionnaire for Evaluating Female Lower Urinary Tract Symptoms (ICIQ-FLUTS) respectively.

Results

Seventy-four women were included in the study. A statistically significant decrease (?28.3%; p < 0.001) of the mean number of micturitions/24 h with a significant increase (37%; p < 0.001) in the mean voided volume per micturition/24 h was observed. The total urine volume/24 h remained unchanged. The number of urinary incontinence episodes was significantly increased 6 weeks after pessary placement (p < 0.001). De novo stress urinary incontinence (SUI) was reported by 16.7% of the initially stress continent women.

Conclusions

Women with coexisting POP and OAB symptoms may experience a significant improvement in micturition frequency and in urgency and frequency symptoms after successful pessary fitting.
  相似文献   
108.
The effect of intramuscular administration of high (30 mg/kg body weight for 3 days) or very high (300 mg/kg body weight for 3 days) doses of a-tocopherol to Wistar rats subjected to total severe warm hepatic ischemia and reperfusion was investigated. After a 60-minute period of total hepatic ischemia and 120 minutes of reperfusion, animals were killed, and liver samples were taken for determination of malondialdehyde (MDA) and histological examinations. Blood samples were also taken for assay of serum a-tocopherol, alanine transaminase (ALT), aspartate transaminase (AST), and lactic dehydrogenase (LDH). Additional animals were followed for a 7-day survival rate determination. Results showed that ischemia and reperfusion decreased the survival rate to 10%, whereas the levels of AST, ALT, and LDH in serum were increased compared with levels in animals that were sham operated. The MDA concentrations in liver were also increased, from 1.142 to 1.567 nmoles/g, whereas the levels of a-tocopherol in serum were decreased from 10.20 to 1.80 mmol/L. Pretreatment with a-tocopherol increased the viability to 50% and 70%, for the high and very high doses, respectively, and decreased the levels of AST, ALT, and LDH in serum. It also decreased the MDA concentrations in liver to 0.975 and 0.774 nmoles/g for the high and very high doses of a-tocopherol, respectively, whereas it increased the level of a-tocopherol in serum to 11.25 and 13.02 mmol/L for the high and very high doses, respectively. Histological examinations showed protection of the liver parenchyma in the animals treated with a-tocopherol.  相似文献   
109.
PURPOSE: To evaluate the efficacy and safety of topical mitomycin C (MMC) for conjunctival-corneal intraepithelial neoplasia (CCIN). METHODS: One patient with primary CCIN received seven applications for 3 minutes of mitomycin C 0.02%, for 2 weeks, on alternative days. The size of the CCIN before and after the treatment and ophthalmic mitomycin C related complications were evaluated. RESULTS: The lesion started to regress during the second month after the last application of mitomycin C, and by the third month it disappeared completely. The patient remains disease free after 36 months follow up. The complications of mitomycin C included a mild tearing and a slight conjunctival hyperemia that resolved 7 days after the end of the therapy. CONCLUSION: Multiple applications of mitomycin C could be an effective treatment for selected cases of CCIN.  相似文献   
110.
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