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71.

Background

C1 lateral mass screw was widely used for fixation of the upper cervical spine. However, massive bleeding from the C1–2 venous plexus is sometimes encountered. In this study, we proposed an alternate method for C1 lateral mass screw insertion, which involves insertion of the screws caudally from the C2 nerve root to reduce bleeding from C1–2 venous plexus.

Methods

Seven patients with atlantoaxial lesions were included in this study. The mean age at surgery was 65.9 (34–82) years. The mean follow-up period was 23.1 (12–38) months. All patients underwent atlantoaxial fusion with C1 lateral mass screws, which were inserted caudally from the C2 nerve root. All screws were inserted using O-arm based navigation system. Operative time, blood loss, C2 nerve root injury and perioperative complications were investigated. The accuracy of C1 screws and bone union were evaluated using postoperative computed tomography.

Results

A total of 13 C1 lateral mass screws were inserted using this method. The mean operative time was 224 (144–305) min. The mean blood loss was 209 (100–357) g. One perioperative complication was observed, which was recurrent laryngeal nerve palsy. There were no vertebral artery or spinal cord injuries. No case of massive bleeding from the C1–2 venous plexus was observed. One patient complained of postoperative occipital neuralgia, which disappeared in 2 weeks. No malposition of C1 lateral mass screws was observed on postoperative computed tomography. Bone union was observed in all patients.

Conclusion

The C1 lateral mass screw insertion caudally from the C2 nerve root may become an alternate method for insertion of C1 screws.  相似文献   
72.
Cardiac angiogenic gene therapy has emerged as a novel treatment approach for patients with intractable ischemic heart disease, aiming at facilitating neovascularization to augment blood flow in the ischemic myocardium by introducing genes encoding for angiogenic factors. While several clinical trials for cardiac angiogenic gene therapy are currently in progress, there remains a discrepancy between impressive preclinical results and their limited clinical findings. On the other hand, positron emission tomography (PET) reporter gene imaging has been developed to monitor expression of transgenes in vivo. PET reporter genes encode for proteins that retain complementary positron-emitting tracers (PET reporter probes), and theoretically any therapeutic gene can be linked and coexpressed with an appropriate PET reporter gene. Consequently, PET reporter gene imaging with a PET reporter probe affords external determination of the location, magnitude, and duration of expression of therapeutic genes noninvasively. Since PET imaging can be performed in various species ranging from mice to humans, in vivo cardiac PET reporter gene imaging could play a critical role in identifying the "missing link" as a powerful translational research tool. In this article, we discuss the role of PET reporter gene imaging in basic and clinical research on cardiac angiogenic gene therapy.  相似文献   
73.
To evaluate the diagnostic accuracy of computed tomography (CT)-based imaging methods for assessing renal vascular anatomy, imaging studies, including standard axial CT, three-dimensional volume-rendered CT (3DVR-CT), and a 3DVR-CT movie, were performed on 30 patients who underwent laparoscopic donor nephrectomy (10 right side, 20 left side) for predicting the location of the renal arteries and renal, adrenal, gonadal, and lumbar veins. These findings were compared with videos obtained during the operation. Two of 37 renal arteries observed intraoperatively were missed by standard axial CT and 3DVR-CT, whereas all arteries were identified by the 3DVR-CT movie. Two of 36 renal veins were missed by standard axial CT and 3DVR-CT, whereas 1 was missed by the 3DVR-CT movie. In 20 left renal hilar anatomical structures, 20 adrenal, 20 gonadal, and 22 lumbar veins were observed during the operation. Preoperatively, the standard axial CT, 3DVR-CT, and 3DVR-CT movie detected 11, 19, and 20 adrenal veins; 13, 14, and 19 gonadal veins; and 6, 11, and 15 lumbar veins, respectively. Overall, of 135 renal vascular structures, the standard axial CT, 3DVR-CT, and 3DVR-CT movie accurately detected 99 (73.3%), 113 (83.7%), and 126 (93.3%) vessels, respectively, which indicated that the 3DVR-CT movie demonstrated a significantly higher detection rate than other CT-based imaging methods (< 0.05). The 3DVR-CT movie accurately provides essential information about the renal vascular anatomy before laparoscopic donor nephrectomy.  相似文献   
74.
Objectives:   To evaluate a clinical pathway of discharge on postoperative day 3 for the tension-free vaginal mesh (TVM) procedure in patients with pelvic organ prolapse (POP).
Methods:   Between May 2006 and December 2007, 305 consecutive women with POP quantification stage 3 or 4 were planned to undergo the TVM procedure in a single general hospital. Excluding five patients with concomitant hysterectomy, a pathway (removal of the indwelling urethral catheter on the next morning, discharge on postoperative day 3) was applied to the remaining 300 patients. The perioperative complications and postoperative hospitalization were prospectively evaluated in this case series.
Results:   Perioperative complications were: bladder injury (11 cases, 3.7%), vaginal wall hematoma (two cases, 0.7%), rectal injury (one case, 0.3%) and temporary hydronephrosis (one case, 0.3%). None needed blood transfusion. The indwelling urethral catheters were removed on the next morning as in the pathway in 287 cases (95.6%), and none required clean intermittent catheterization at home. Postoperative hospitalization was within 3 days in 280 cases (93.3%). The six cases (2.0%) with longer hospitalization were due to complications (two cases of bladder injury, one of rectal injury, one of blood loss over 200 mL, one of temporary urinary retention, and one of hydronephrosis). Two patients were re-hospitalized within one month due to vaginal bleeding or gluteal pain.
Conclusions:   Patients generally accepted the pathway of discharge on postoperative day 3 in spite of the Japanese culture preferring a longer hospital stay.  相似文献   
75.

Background

CD133 is a transmembrane protein that is proposed to be a stem cell marker of colorectal cancer (CRC); however, the correlation between CD133 expression and survival of CRC patients with liver metastasis has not been fully examined.

Methods

CD133 expression was evaluated immunohistochemically, both in primary tumors and synchronous liver metastases of 88 consecutive CRC patients, as well as recurrent lesions in the remnant liver of 27 of these 88 patients. The relationship between CD133 expression and clinicopathological characteristics, recurrence-free survival, and overall survival (OS) was analyzed.

Results

CD133 expression in liver metastases (mCD133) was detected in 50 of 88 patients (56.8 %), and had significant correlation with CD133 expression in primary lesions (pCD133) (p < 0.001). CD133 expression in liver recurrent lesions (recCD133) also had a significant correlation with mCD133 (p < 0.001). mCD133+ patients had significantly longer disease-free survival (p = 0.043) and OS (p = 0.014) than mCD133? patients. In addition, mCD133+ patients had a significantly lower rate of extrahepatic recurrence (p < 0.001).

Conclusions

Patients without CD133 expression in liver metastasis had significantly shorter survival, perhaps because mCD133? patients had a significantly higher rate of extrahepatic recurrence.
  相似文献   
76.
The objective of this study was to evaluate in vivo kinematics of a high-flexion, posterior-stabilized fixed-bearing, total knee arthroplasty in weight-bearing deep knee-bending motion. A total of 20 knees implanted with the Scorpio Non-Restrictive Geometry knee system in 17 patients were assessed in this study. The Scorpio Non-Restrictive Geometry is a recent implant design with modifications made to accommodate a higher flexion range of motion and greater axial rotation, particularly during more functionally demanding activities. Patients were examined during a deep knee-bending motion using fluoroscopy, and femorotibial motion was determined using a 2-dimensional to 3-dimensional registration technique. The average flexion angle was 126.5° (110°-149°). The femoral component demonstrated a mean of 13.5° (5.2°-21°) external rotation. The external rotation increased up to maximum flexion. The pivot pattern was a medial pivot pattern similar to that reported in normal knee kinematics.  相似文献   
77.
We evaluated the neural substrates of cross-modal binding and divided attention during audio-visual speech integration using functional magnetic resonance imaging. The subjects (n = 17) were exposed to phonemically concordant or discordant auditory and visual speech stimuli. Three different matching tasks were performed: auditory-auditory (AA), visual-visual (VV) and auditory-visual (AV). Subjects were asked whether the prompted pair were congruent or not. We defined the neural substrates for the within-modal matching tasks by VV-AA and AA-VV. We defined the cross-modal area as the intersection of the loci defined by AV-AA and AV-VV. The auditory task activated the bilateral anterior superior temporal gyrus and superior temporal sulcus, the left planum temporale and left lingual gyrus. The visual task activated the bilateral middle and inferior frontal gyrus, right occipito-temporal junction, intraparietal sulcus and left cerebellum. The bilateral dorsal premotor cortex, posterior parietal cortex (including the bilateral superior parietal lobule and the left intraparietal sulcus) and right cerebellum showed more prominent activation during AV compared with AA and VV. Within these areas, the posterior parietal cortex showed more activation during concordant than discordant stimuli, and hence was related to cross-modal binding. Our results indicate a close relationship between cross-modal attentional control and cross-modal binding during speech reading.  相似文献   
78.
A home screening device, LT-200, can record data on both breathing conditions and body positions during sleep for up to 3 consecutive days in patients with obstructive sleep apnea (OSAS). We investigated the usefulness of the LT-200 device for follow-up of OSAS. Eighteen patients (age 51.0 +/- 10.8 years, mean +/- SD) were enrolled in this study. Standard polysomnography (PSG) was performed on all patients. The number of apnea/hypopnea episodes per hour (apnea/hypopnea index: AHI), the total time that nocturnal oxygen saturation was < 90% (oxygen desaturation time: ODT), and the minimum oxygen saturation during sleep (lowest Spo2) were calculated. We used the LT-200 and PSG to evaluate any improvement in the data obtained after auto-continuous positive airway pressure (auto-CPAP) therapy. AHI was also measured using the LT-200 in three sleep positions to evaluate the efficacy of the lateral position. AHI, ODT, and lowest Spo2 values did not differ significantly between the PSG and LT-200 recordings on the control and therapy nights. The LT-200 recordings showed that AHI, ODT, and lowest Spo2 tended to be better on the second night of auto-CPAP therapy than on the first. AHI was significantly lower in the right and left lateral sleep positions than that in the supine position. Our findings suggest that since the LT-200 device provides important information about the severity of OSAS, the efficacy of auto-CPAP therapy, and body position under unattended conditions in the home. It may prove to be a useful tool for following up patients.  相似文献   
79.
Expression of fibrogenic cytokines in desmoplastic malignant melanoma   总被引:4,自引:0,他引:4  
Desmoplastic malignant melanoma (DMM) consists of amelanotic spindle-shaped melanoma cells and is accompanied by desmoplasia with fibrous stromata. It has a strong tendency for local infiltrative growth and recurrence and a propensity for neurotropism. It is not yet known which cytokine is responsible for the desmoplasia in DMM. In the present study, we investigated the roles of several fibrogenic cytokines and cytokine receptors in DMM: basic fibroblast growth factor (bFGF), connective tissue growth factor (CTGF), transforming growth factor-β, platelet-derived growth factor (PDGF) and PDGF receptors. Immunostaining and in situ hybridization were conducted in four cases of DMM and four cases of amelanotic malignant melanoma (AMM) as negative controls for desmoplasia. PDGF-β receptor, bFGF and CTGF were intensely expressed in the DMM specimens in comparison with the AMM specimens. The reaction of PDGF-B ligand and CTGF to PDGF-β receptor, in addition to the expression of bFGF, may contribute to the desmoplasia in DMM.  相似文献   
80.
Endothelial dysfunction is a hallmark of vasculopathy associated with systemic sclerosis (SSc). Reactive hyperemia peripheral arterial tonometry is a rapid and non-invasive technique to assess peripheral microvascular endothelial function by measuring changes in digital pulse volume during reactive hyperemia. Low scores of the reactive hyperemia index (RHI) imply an impaired vasodilatory response and, accordingly, impaired endothelial and vascular health. To investigate the clinical significance of the RHI in SSc patients, RHI values were measured in 43 SSc patients and 10 healthy controls. In diffuse cutaneous SSc (dcSSc) patients, RHI values were significantly decreased compared with healthy controls, and inversely correlated with disease duration. In total SSc patients, there was a significant inverse correlation between RHI values and skin score, and interstitial lung disease was associated with the decrease in RHI values. Among vascular symptoms, the current and past history of digital ulcers was seen more frequently in patients with decreased RHI values than in those with normal RHI values. Although no SSc patients had pulmonary arterial hypertension, an inverse correlation was evident between RHI values and mean pulmonary arterial pressure measured by right heart catheterization. These results indicate that the decrease in RHI values is associated with skin fibrosis, interstitial lung disease, digital ulcers and pulmonary vascular involvement leading to pulmonary arterial hypertension, supporting the canonical idea that endothelial dysfunction is a critical event underlying the development of tissue fibrosis and vascular complications in SSc.  相似文献   
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