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81.
Magnetic resonance imaging in acoustic neurinoma. Comparison with CT   总被引:2,自引:0,他引:2  
MRI and CT were performed in 16 patients with 17 acoustic neurinomas. MRI was superior to CT in the detection of small acoustic neurinomas, in the demonstration of intracanalicular extension and in the differentiation with cerebellopontine angle meningiomas. Overall advantages of MRI over CT included better tissue contrast, absence of bone artifacts and easy multiplanar imaging.  相似文献   
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Previous in vitro experiments demonstrated the reduced microhardness of calcium oxalate monohydrate (COM) calculi, relative to dry values, when saturated with an alkaline solution (pH = 9.5). Nineteen patients with a COM calculus in the distal ureter which had been resistant to prior extracorporeal shock wave lithotripsy in situ, were treated when the stone was surrounded by alkaline urine. The urine of 14 patients was alkalinized orally by administration of acetazolamine and citrate solution; in 5 other patients direct percutaneous irrigation of sodium bicarbonate via a nephrostomy tube was carried out. The urinary pH just before lithotripsy was greater than or equal to 9 in 17/19 patients. 4,000 shock waves, averaging 18.1 kV generated by the Siemens Lithostar, were delivered onto the calculus. No significant increase of comminution rate was apparent at radiographic control immediately after the treatment and only in half of the cases was evacuation obtained within 3 months.  相似文献   
85.
The feasibility of imaging the adrenal glands during routine upper abdominal examinations was studied for 100 consecutive patients, 47 males and 53 females. The mean patient age was 46 years and the mean weight 63 kg. The suprarenal areas were scanned in a slightly oblique frontal plane through the intercostal spaces with the patient recumbent. The right adrenal gland was detected in 92 per cent of the patients, with a mean examination time of less than one minute. Visualization of the left adrenal gland was more difficult and was successful in only 71 per cent, even where additional views in the right lateral decubitus or erect position were added. The mean examination time on the left was 2 1/2 minutes. Complete visualization of the adrenal gland is impossible in one single plane because of the complex shape of the organ, which necessitates multiple contiguous scan planes. In 13 per cent of the visualized adrenals, cortex and medulla could be differentiated.  相似文献   
86.
A patient presented with large intrahepatic tumoral masses 36 yr after the initial detection of multiple liver metastases during a gastrectomy. The operation had been performed to remove four ulcerated polypoid gastric lesions. Reexamination of the previous liver and gastric biopsy specimens revealed a gastric leiomyoblastoma with metastases to the liver. The smooth muscle origin of this tumor was confirmed by positive staining for desmin intermediate filaments. This very long survival is extremely unusual in cases of metastatic gastric leiomyoblastoma.  相似文献   
87.
BACKGROUND & AIMS: Infliximab therapy is an effective approach to treating Crohn's disease. Development of antinuclear antibodies has been described in patients treated, but the size of the problem and the relationship with autoimmunity have not been investigated. We investigated the occurrence of antinuclear antibodies in 125 consecutive Crohn's disease patients and studied the relationship with symptoms of autoimmunity. METHODS: Autoantibodies and clinical data were investigated before and 1, 2, and 3 months after infliximab infusion. If antinuclear antibodies were > or =1:80, further study of double-stranded DNA, single-stranded DNA, histones, and ENA was performed. RESULTS: Cumulative antinuclear antibody incidence at 24 months was 71 of 125 (56.8%). Almost half of these patients developed antinuclear antibodies after the first infusion, and >75% became antinuclear antibody positive after fewer than 3 infusions. So far, only 15 of 71 patients have become seronegative, after a median of 12 months. Of 43 antinuclear antibody-positive patients who were further subtyped, 14 of 43 (32.6%) had double-stranded DNA, 17 (39.5%) had single-stranded DNA, 9 (20.9%) had antihistone, and 0% were ENA positive. Two patients (both antihistone and double-stranded DNA positive) developed drug-induced lupus without major organ damage, and 1 developed autoimmune hemolytic anemia. Antinuclear antibodies were associated with the female sex (odds ratio, 3.166; 95% confidence interval, 1.167-8.585; P = 0.024) and with papulosquamous or butterfly rash (odds ratio, 10.016; 95% confidence interval, 1.708-58.725; P = 0.011). CONCLUSIONS: The cumulative incidence of antinuclear antibodies was 56.8% after 24 months in this cohort of infliximab-treated Crohn's disease patients. Antinuclear antibodies persisted up to 1 year after the last infusion, and only a few patients became seronegative. Two patients developed drug-induced lupus erythematosus. Antinuclear antibodies were associated with the female sex and skin manifestations.  相似文献   
88.
The genetic basis combined with the sporadic occurrence of amyotrophic lateral sclerosis (ALS) suggests a role of de novo mutations in disease pathogenesis. Previous studies provided some evidence for this hypothesis; however, results were conflicting: no genes with recurrent occurring de novo mutations were identified and different pathways were postulated. In this study, we analyzed whole‐exome data from 82 new patient‐parents trios and combined it with the datasets of all previously published ALS trios (173 trios in total). The per patient de novo rate was not higher than expected based on the general population (= 0.40). We showed that these mutations are not part of the previously postulated pathways, and gene–gene interaction analysis found no enrichment of interacting genes in this group (P = 0.57). Also, we were able to show that the de novo mutations in ALS patients are located in genes already prone for de novo mutations (< 1 × 10‐15). Although the individual effect of rare de novo mutations in specific genes could not be assessed, our results indicate that, in contrast to previous hypothesis, de novo mutations in general do not impose a major burden on ALS risk.  相似文献   
89.
Aminosalicylates (5-ASA, sulfasalazine and mesalazine) play a central role in the treatment of ulcerative colitis (UC). For acute treatment of mild to moderate flares and in maintenance treatment, their efficacy has been established. Since ulcerative colitis is limited to the distal colon in two thirds of the patients, topical therapy also plays an important role. In mild/moderate active disease 5-ASA 4 g/d is as effective as oral corticosteroids. Ulcerative proctitis is treated with 2 x 500 mg or 1 x 1 g suppositories and proctosigmoiditis with 1 to 4 g enemas. Oral 5-ASA is also safe in maintenance treatment and is generally well tolerated. The risk of colorectal tumours is increased in patients with longstanding ulcerative colitis and epidemiological evidence indicates that chronic 5-ASA treatment reduces this risk. However, at present there is insufficient evidence to maintain patients on life-long 5-ASA maintenance treatment for this indication.  相似文献   
90.
Prominent dural enhancement was noted in 10 (16%) of 61 superficial malignant intracranial tumors studied with contrast-enhanced MR imaging during a 2-year period. Included were six glioblastomas, three parenchymal metastases, and one case of dural metastasis. Seven patients had surgery. In four, there was extensive leptomeningeal invasion in the center of the lesion. In two of these lesions there was firm attachment of the center of the tumor to the dura, but without dural invasion despite extensive external carotid artery supply to the tumor in one case. In two cases the overlying dura was normal, and there was no leptomeningeal tumoral invasion. In the case of dural metastasis, huge nodular lesions were present along the inner aspect of the dura. In none of the cases did prominent dural enhancement adjacent to the tumor correspond with tumoral invasion or extension to the dura. Prominent dural enhancement on contrast-enhanced MR images appears to be much less frequent in malignant tumor than in meningioma, where it is seen in up to 60% of the cases. We believe this finding is more likely to represent reactive changes of the dura than tumoral invasion.  相似文献   
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