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81.
82.
83.
A 4-year-old girl suffered intraventricular and subarachnoid hemorrhage during endoscopic third ventriculostomy. Cerebral angiography revealed a traumatic basilar aneurysm secondary to basilar artery injury. The aneurysm was treated with selective endovascular embolization using Guglielmi detachable coils. We review some therapeutic features of traumatic basilar aneurysms after endoscopic third ventriculostomy and describe the feasibility of endovascular selective therapy to manage these lesions successfully.  相似文献   
84.
Development of a computer assisted system aimed at RFA liver surgery   总被引:1,自引:0,他引:1  
Radio frequency ablation (RFA) is a minimally invasive treatment for either hepatocellular carcinoma or metastasis liver carcinoma. In order to resect large lesions, the surgeon has to perform multiple time-consuming destruction cycles and reposition the RFA needle for each of them. The critical step in handling a successful ablation and preventing local recurrence is the correct positioning of the needle. For small tumors, the surgeon places the middle of the active needle tip in the center of the tumor under intra-operative ultrasound guidance. When one application is not enough to cover the entire tumor, the surgeon needs to repeat the treatment after repositioning of the needle, but US guidance is obstructed by the opacity stemming from the first RFA application. In this case the surgeon can only rely on anatomical knowledge and the repositioning of the RFA needle becomes a subjective task limiting the treatment accuracy. We have developed a computer assisted surgery guidance application for this repositioning procedure. Our software application handles the complete process from preoperative image analysis to tool tracking in the operating room. Our framework is mostly used for this RFA procedure, but is also suitable for any other medical or surgery application.  相似文献   
85.
Background: During labor, ephedrine is widely used to prevent or to treat maternal arterial hypotension and restore uterine perfusion pressure to avoid intrapartum fetal asphyxia. However, the effects of ephedrine on uterine blood flow have not been studied during uterine contractions. The purpose of the study was to assess the effects of ephedrine on uterine artery velocities and resistance index using the Doppler technique during the active phase of labor.

Methods: Ten normotensive, healthy parturients with uncomplicated pregnancies at term received intravenous ephedrine during labor to increase mean arterial pressure up to a maximum of 20% above their baseline pressure. Peak systolic and end-diastolic Doppler flow velocities and resistance indices were measured in the uterine artery before and immediately after administration of bolus intravenous ephedrine and after ephedrine washout. Umbilical and fetal middle cerebral arterial resistance indices and fetal heart rate were also calculated.

Results: After ephedrine administration, mean arterial pressure increased by 17 +/- 4%. End-diastolic flow velocity in the uterine artery at peak amplitude of uterine contraction was restored to 74% of the value observed in the absence of contraction. The systolic velocity was totally restored, and the uterine resistance index was significantly decreased, compared with the values in the absence of contraction. Between uterine contractions, ephedrine induced similar but less marked effects. Fetal hemodynamic parameters were not altered by ephedrine administration.  相似文献   

86.
PURPOSE: Some studies imply that increasing the number of prostate biopsy cores may improve the cancer detection rate. We performed a prospective study to evaluate pain and morbidity after an extensive transrectal ultrasound guided 10-core biopsy protocol. MATERIALS AND METHODS: A total of 289 consecutive men with abnormal digital rectal examination findings and/or increased prostate specific antigen underwent extensive prostate biopsy involving 6 sextant and 4 peripheral biopsies. Each received an information leaflet a few days before the procedure. A single dose of fluoroquinolone and a rectal enema were administered before biopsy. In no case was the procedure performed using anesthesia. Immediately after biopsy patients were asked to complete a self-administered nonvalidated questionnaire evaluating the degree of pain and/or discomfort using a visual analog scale. In another questionnaire they listed the side effects noticed during month 1 after biopsy. RESULTS: Although 48% of the 275 men who completed the initial questionnaire reported anxiety before the procedure, 78.8% of them were completely reassured by the information brochure. Of the 275 patients 47.6% described the procedure as painful, including only slightly painful (analog visual scale 3 or less) in 67.9%, while 33.8% described it as uncomfortable but not painful and 18.6% thought that it was neither painful nor uncomfortable. Of the 115 patients who engaged in sexual intercourse during month 1 after the procedure 78.3% noticed hematospermia an average of 10.9 days in duration. Of the 164 men who completed questionnaire 2, 74.4% noticed hematuria an average of 2.7 days in duration, 3.7% noticed pyrexia and 1.2% noticed acute prostatitis. In the 59 patients (36%) who reported delayed perineal pain it was slight in 64.4%, moderate in 30.5% and severe in 5.1%. No patient required hospitalization. CONCLUSIONS: Although minor complications are common, the extensive 10-core prostate biopsy protocol is associated with few major complications. The occurrence and intensity of pain and discomfort are in the range reported after the standard 6-core biopsy protocol.  相似文献   
87.
BACKGROUND: The purpose of this retrospective study was to report the results, after a minimum of 18.5 years of follow-up, in a consecutive series of total hip arthroplasties performed with an alumina-on-alumina combination. METHODS: One hundred and eighteen consecutive total hip arthroplasties were performed in 106 patients between 1979 and 1980. The prostheses combined a 32-mm alumina head and an all-alumina socket. Both components were cemented in eighty-five hips, both components were implanted without cement in twenty-nine, and only the stem was cemented in four. The mean age of the patients at the time of the index arthroplasty was 62.2 years (range, thirty-two to eighty-nine years). RESULTS: At the 18.5 to 20.5-year follow-up evaluation, forty-five patients (fifty-one hips) were alive and had not had a revision, twenty-five patients (twenty-five hips) had undergone revision of one or both components, twenty-seven patients (thirty hips) had died, and nine patients (twelve hips) had been lost to follow-up. The mean Merle d'Aubigné hip score (and standard deviation) was 16.2 +/- 1.8 points at the latest follow-up evaluation. The rate of survival at twenty years, with revision for any reason as the end-point, was 85.6% for the cementless cups compared with 61.2% for the cemented cups and 84.9% for the cementless stems compared with 87.3% for the cemented stems. Wear of the prosthetic components was undetectable on plain radiographs. Periprosthetic cystic or scalloped lesions requiring the use of allograft bone during revision were present in three of the twenty-five revised hips. In addition, seven hips had moderate acetabular osteolysis treated with a 4-mm-larger cup. No fracture of the alumina socket or head was recorded. The mean acetabular wear rate in this series was <0.025 mm/yr. CONCLUSION: With the alumina-on-alumina total hip arthroplasty, minimal wear rates and limited osteolysis can be expected up to twenty years after the operation, provided that sound acetabular component fixation is obtained.  相似文献   
88.
We describe representations of the visual field in areas 18, 19 and 21 of the ferret using standard microelectrode mapping techniques. In all areas the azimuths are represented as islands of peripheral visual field surrounded by central visual field representation. The zero meridian was found at the 17/18 and 19/21 borders; at the 18/19 and anterior border of 21 the relative periphery of the visual field was found. In areas 18 and 19, elevations are represented in a smooth medio-lateral progression from lower to upper visual field. In several cases the elevations in area 21 evidenced a similar medio-lateral progression; however, in others the elevations exhibited a split representation of the horizontal meridian. Anatomically determined callosal connections coincided with the representation of azimuths near the zero meridian. Medio-lateral bands of callosal connectivity that straddle the 17/18 and 19/21 borders are connected by bridges of callosally projecting cells. Acallosal cortical islands corresponded to the peripheral visual field and were found straddling the 18/19 border and the anterior border of area 21. The results are discussed in relation to callosal connectivity and retinotopy in extrastriate visual cortex and to proposed homologies of carnivore and primate visual cortex.  相似文献   
89.

Objective

To report postnatal tracheal changes after in utero fetoscopic balloon tracheal occlusion in severe congenital diaphragmatic hernia (CDH).

Design

Case series.

Setting

Tertiary care center, CDH National Reference Center.

Patients

Seven consecutive newborn infants with severe CDH who underwent fetoscopic balloon tracheal occlusion.

Interventions

Flexible laryngotracheoscopy and histological aspect observed at necropsy in 2 nonsurvivors.

Results

All infants displayed elongation and relaxation of the posterior tracheal wall, intermittently obstructing the lumen during tidal breathing. Whereas the cartilage displayed adequate rigidity, the pars membranacea appeared both flaccid and loose. Tracheal widening (tracheomegaly) was seen in all cases. Histology (n = 2) pointed to structural modifications throughout the pars membranacea, that is, loss of epithelial folding and of longitudinal elastic network and focal muscular disruption. The cartilage displayed no visible or histologic changes. The above tracheal changes were not symptomatic, except for a barking cough during increased respiratory efforts.

Conclusions

Tracheal widening and intermittent collapse of the posterior wall of the trachea during tidal breathing was found in 7 consecutive newborns who underwent fetoscopic balloon tracheal occlusion, causing mild clinical symptoms. Endoscopic tracheal assessment might provide useful information in children with CDH, in particular, when they underwent in utero fetoscopic balloon tracheal occlusion.  相似文献   
90.
Papillary tumor of the pineal region (PTPR) is a recently described tumor entity thought to arise from the specialized ependyma of the subcommissural organ. Whereas histologic features of PTPR are well defined, data on the prognostic value of PTPR remain scarce. We therefore investigated clinicopathologic features, including data on progression-free survival and overall survival, in a retrospective series of 31 PTPR. The age of the 14 males and 17 females ranged from 5 to 66 years (median age, 29 years). Histologically, all tumors were characterized by an epithelial-like growth pattern in which the vessels were covered by layers of columnar or cuboidal tumor cells forming perivascular pseudorosettes. Most of the tumor cells showed strong expression of neuron-specific enolase, cytokeratins (particularly CK18), S-100 protein, and vimentin. Most PTPRs examined also expressed microtubule-associated protein-2. Expression of synaptophysin, epithelial membrane antigen, transthyretin, neural cell adhesion molecule, and nestin was encountered in some tumors. Gross total resection could be achieved in 21 of 31 cases; 15 patients received radiotherapy on resection of the primary tumor. Nevertheless, the majority of patients experienced recurrences; 5-year estimates for overall survival and progression-free survival were 73% and 27%, respectively. To conclude, the clinical course of PTPR is characterized by frequent local recurrence, and the value of radiotherapy on disease progression will need to be investigated in future prospective trials.  相似文献   
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