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51.

Purpose

To investigate radiographic criteria for scapholunate instability (SLI) in the setting of distal radius fracture (DRF) confirmed by arthroscopy.

Methods

Eighty-eight wrists with DRF treated by open reduction and internal fixation and assessed for SLI arthroscopically were evaluated. The scapholunate distance (SLD) was measured by preoperative posteroanterior wrist radiography and computed tomography (CT). SLD on radiographs was measured as the distance between the scaphoid cortex and the lunate cortex at the center of the scapholunate joint. SLDs were measured at the volar end (A1), center (A2), and dorsal end (A3) of the scapholunate joint on the central CT axial slice; and at the proximal end (C1), center (C2), and distal end (C3) of the scapholunate joint on the central CT coronal slice. Wrists were divided into three groups by arthroscopic assessments: stable (normal, Geissler grade 1 or 2), G3 (Geissler grade 3), and G4 (Geissler grade 4). SLD measurements on radiographs and CTs (A1–C3) were compared among the three groups. Receiver-operating characteristic (ROC) curve analyses were performed to evaluate the abilities of SLD measurements on radiographs and CTs to identify SLI in wrists with DRF. Interobserver and intraobserver reliabilities of SLD measurements on radiographs and CTs were analyzed by intraclass correlation coefficients (ICCs).

Results

SLDs of C3 differed significantly among the G3 and G4 groups, and among the stable and G4 groups. The area under the curve on ROC curve analysis was 0.855 for the SLD of C3, which was larger than that for SLD on radiographs. For C3, the intraobserver ICC was 0.832 and interobserver ICC was 0.73.

Conclusions

SLD at the distal end of the scapholunate joint on the central coronal CT slice was the most appropriate measurement for discrimination of Geissler grade 4 SLI in wrists with DRF.

Level of evidence

Level 2  相似文献   
52.
Heparin-induced thrombocytopenia (HIT) type II is characterized by a decrease in platelet count and thrombosis following heparin administration. We anesthetized a 67-year-old woman with suspected HIT type II undergoing carotid endarterectomy (CEA). Preoperatively, the patient had received anticoagulation therapy with heparin for cerebral infarction due to thrombosis and she developed thrombocytopenia with deterioration of cerebral infarction. Platelet level recovered by discontinuation of heparin and platelet infusion. During the surgical procedure, a substitution for heparin as an anticoagulant was necessary and we used argatroban, a direct thrombin inhibitor, with monitoring activated coagulation time (ACT). The ACT values were maintained above 200 sec during endoarterectomy and the operation was successfully carried out. We believe that argatroban is one of the choices for anticoagulants in a patient with HIT type II.  相似文献   
53.
Summary Male and female F344 rats were continuously administered N-methyl-N-nitrosourea (MNU) in their drinking water at concentrations of 200 or 100 ppm, and both sexes of ACI/N rats were given MNU at a concentration of 200 ppm. By the 42nd week of the experiment, high incidences of brain/spinal cord tumors were observed in both strains of rats. Histologically, many of them were astrocytomas or anaplastic astrocytomas. In addition, malignant neurinomas were also detected in the spinal nerve roots and trigeminal nerves, although their incidences were rather low. There was no difference in the type and incidence of these neurogenic tumors between the two strains of rats. Tumors of the tongue and esophagus were mainly observed in the high-dose group of F344 rats and those of the glandular stomach were observed in the low-dose group of F344 rats. In ACI/N rats, tumors of the heart and renal pelvis were detected. The organ-specific carcinogenicity of MNU in these two strains of rats was compared with that of MNU in Donryu rats. It was demonstrated that organ specificity of MNU given orally was influenced not only by the strain of rats but also by the dose level.Part of this work was presented at the 43rd Annual Meeting of the Japanese Cancer Association in Fukuoka, October 1984. This work was supported by grants-in-aid for cancer research from the Ministry of Education, Science and Culture  相似文献   
54.
For islet transplantation, maintaining organ viability after pancreas procurement is critically important for optimal graft function and survival. We recently reported that islet yield was significantly higher in the modified ET-Kyoto (MK) solution, which includes a trypsin inhibitor (ulinastatin), compared with the UW solution, and that the advantages of MK solution are trypsin inhibition and less collagenase inhibition. In this study, we compared ulinastatin with other trypsin inhibitors, gabexate mesilate, and nafamostat mesilate, in preservation solution for islet isolation. Ulinastatin was easily dissolved in ET-Kyoto solution, while ET-Kyoto with gabexate mesilate and nafamostat mesilate became cloudy immediately after addition. Although there were no significant differences in islet yield among the three groups, viability was significantly higher for the MK group than for the GK group or the NK group. The stimulation index was significantly higher for the MK group than for the GK group. In summary, there are no other trypsin inhibitors that are more effective than ulinastatin. Based on these data, we now use ET-Kyoto solution with ulinastatin for clinical islet transplantation.  相似文献   
55.
BACKGROUND: Renal urinary concentration is associated with enhanced expression of rBSC1, a rat sodium cotransporter, in the thick ascending limb of Henle. Increased expression of rBSC1 was reported recently in nephrogenic diabetes insipidus induced by lithium chloride (Li nephropathy). However, the pathophysiological implication of altered rBSC1 expression has not yet been investigated. METHODS: Li nephropathy was induced in rats by an oral administration of 40 mmol lithium/kg dry food. In rats with reduced urinary osmolality to less than 300 mOsm/kg H2O, we examined the expression of rBSC1 mRNA and protein, plasma arginine vasopressin (AVP) and RNA expression of kidney-specific water channel, aquaporin-2 (AQP2), of collecting ducts. Rats with Li nephropathy were treated with furosemide (3 mg/kg body weight), which blocks the activity of rBSC1, and changes in urine concentration, plasma AVP, medullary accumulation of Li ions, and apical AQP2 expression were determined. RESULTS: Rats with Li nephropathy showed increased rBSC1 RNA and protein expression and reduced AQP2 RNA. In these rats, furosemide, which induces dilution of urine and polyuria in normal rats, resulted in a progressive and significant rise in urine osmolality from 167 +/- 11 (mean +/- SD) at baseline to 450 +/- 45 mOsm/kg H2O at three hours after administration, and significant oliguria. In the same rats, plasma AVP decreased significantly from 5.7 to 3.0 pg/mL. In addition, recovery of apical AQP2 expression was noted in a proportion of epithelial cells of the collecting ducts. Although Li+ in the renal medulla was slightly lower in rats with Li nephropathy treated with furosemide, statistical significance was not achieved. CONCLUSIONS: Our results suggest that dehydration or high plasma AVP results in an enhanced rBSC1 expression in Li nephropathy, and that rBSC1 expression is closely associated with the adverse effects of Li ions on collecting duct function.  相似文献   
56.
A 43-year-old male with a history of autosomal dominant polycystic kidney disease (ADPKD) was admitted to our center with severe abdominal pain and was diagnosed with acute pancreatitis. CT showed multiple cysts in the liver and both kidneys along with ADPKD and a cystic mass, 4 cm in diameter, in the pancreatic head. The main pancreatic duct was dilated to 1 cm in diameter. The patient was diagnosed with acute pancreatitis due to intraductal papillary mucinous tumor (IPMT), and pancreatoduodenectomy was performed. Histologic examination revealed a multiloculated cystic tumor filled with mucin in the head of the pancreas. Microscopically, the tumor was diagnosed as adenocarcinoma and was found to have invaded the main pancreatic duct. Although, in addition to our case, only seven cases with association between ADPKD and malignant neoplasms have been reported, five of these cases had neoplasms arising from the pancreas. Therefore, we suggest that some genetic interactions may exist between ADPKD and pancreatic carcinogenesis.  相似文献   
57.
58.
The standard technique using lymphoscintigraphy, blue dye and a gamma probe has established a reliable method for sentinel node biopsy for skin cancer. However, the detection rate of cervical sentinel lymph nodes (SLN) is generally lower than that of inguinal or axillary SLN because of the complexity of lymphatic drainage in the head and neck region and the “shine‐through” phenomenon. Recently, indocyanine green fluorescence imaging has been reported as a new method to detect SLN. We hypothesized that fluorescence navigation with indocyanine green in combination with the standard technique would improve the detection rate of cervical sentinel nodes. We performed cervical sentinel node biopsies using the standard technique in 20 basins of 18 patients (group A) and using fluorescence navigation in combination with the standard technique in 12 basins of 16 patients (group B). The mean number of sentinel nodes was two per basin (range, 1–4) in group A and three per basin (range, 1–5) in group B. The detection rate of sentinel nodes was 83% (29/35) in group A and 95% (36/38) in group B. The false‐negative rate was 6% (1/18 patients) in group A and 0% in group B. Fluorescence navigation with indocyanine green may improve the cervical sentinel node detection rate. However, greater collection of data regarding the usefulness of cervical sentinel node biopsy using indocyanine green is necessary.  相似文献   
59.
Leg ulcers are often complicated in patients with rheumatoid arthritis (RA), however, the etiology is multifactorial. We examined the cases of leg ulceration or gangrene in seven RA patients who were hospitalized over the past 3 years. One patient was diagnosed as having pyoderma gangrenosum. Although vasculitis was suspected in three patients, no histological evidence was obtained from the skin specimens. In these patients, angiography revealed the stenosis or occlusion of digital arteries. In the remaining three patients, leg ulcers were considered to be due to venous insufficiency. Treatment should be chosen depending on the causes of leg ulcers.  相似文献   
60.
PURPOSE: We reviewed the records of 10 patients who had impending central retinal vein occlusion in order judge whether anticoagulant treatment with warfarin potassium (Warfarin) was indicated. PATIENTS: 6 men and 4 women, ranging in age from 25 to 83 (average 55) years were studied. RESULTS: Of 6 eyes, retinal hemorrhage disappeared completely within 6 months. Four patients whose visual acuity was 0.1 or less at one month needed photocoagulation. Four other patients whose late venous circulation time at fluorescein angiography improved within 30 seconds had good visual prognosis, 3 eyes of 4 patients aged 65 or older were not successful in regaining their visual acuity. CONCLUSION: Warfarin was not effective for patients who had clearly lost their visual acuity and the elderly in this series. Late venous circulation time at fluorescein angiography was a useful index for this treatment.  相似文献   
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