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71.
Cushing's disease (CD), the chronic endogenous hypercortisolism derived from an ACTH-secreting pituitary adenoma, and multiple osteochondromatosis (MO), a congenital mesoderm dyschondroplasia, represent two distinct rare neoplastic diseases. Clinical appearance of MO usually occurs during the first-second decade of life. In fact, the growth of osteochondromas parallels the patient's growth, then becoming quiescent after the closure of the epiphyses and the achievement of final stature. Here we describe an uncommon case of a patient with a long-term history of childhood-onset CD, who surprisingly developed MO during the third decade of life, after the remission of CD. Indeed, a female patient had been followed for CD from the age of 12 to the age of 24 years, when CD definitively remitted. At the age of 26 the patient complained progressively worsening backache and pain at level of hips and feet. Standard radiography of skeleton showed multiple bone dysmorphisms at level of the four limbs, spine and pelvis consistent with multiple osteochondromas and exostoses. A diagnosis of MO was performed. Total body bone scintigraphy with 99mTc-MDP revealed an increased uptake of the radioligand, suggesting an increased metabolic turnover in correspondence of the majority of the osteochondromas. However, the negativity of the majority of the lesions at 99mTc-DMSA scintigraphy and the histological diagnosis of benign osteochondroma of the only positive lesion at 99mTc-DMSA evidenced that the high metabolic activity of the osteochondromas was not due to malignant transformation. However, the activity of the lesions was highly surprising considering that they usually become quiescent after the achievement of the final stature. In last analysis, the uncommon characteristics of MO and, particularly, its occurrence after stable remission of hypercortisolism, suggests a possible role of glucocorticoids in influencing the clinical course of the skeletal disease. The inhibitory effect of hypercortisolism on bone growth and maturation could explain the block in the proliferation of skeletal lesions during the developmental age, where CD was in the active phase, and the opposite effect of stimulation of the ostochondromas growth during stable normalization of cortisol secretion, after CD remission.  相似文献   
72.
The aim of the study was to assess the incidence of hospital and community acquired bacterial pneumonia in HIV-infected subjects prior to and after the introduction of highly active antiretroviral therapy (HAART). We studied 266 patients with bacterial pneumonia over two separate periods, 154 in the first period and 112 in the second period. A statistically significant difference in the incidence of bacterial pneumonia in the two study periods was observed ranging from 13.1 to 8.5 episodes per 100 persons. The incidence of community-acquired bacterial pneumonia decreased from 10.7 to 7.7 (P=0.01), while that of nosocomial episodes decreased from 2.4 to 0.8 episodes (P=0.003). Low levels of peripheral CD(4+) cells (<100/mm(3)) and intravenous drug abuse (IVDA) were significantly associated with the development of community-acquired bacterial pneumonia, while an increasing value of APACHE III score and prolonged hospitalisation increased the risk of nosocomial bacterial pneumonia in both study periods.  相似文献   
73.
Abdominal lymph node chains and route of lymph drainage of various organs (stomach, duodenum, liver, gallbladder, pancreas, small intestine, appendix, blind intestine, colon rectum) are analyzed according to their location. The role of conventional radiology and diagnostic imaging is evaluated in the study of abdominal lymphatic system with particular reference to lymphangiography and the new procedures of sonography, CT and MRI. Present methods used in inflammatory abdominal lymphadenopathy with special attention to tuberculous lymphadenitis, liver cirrhosis, neoplastic abdominal lymphadenopathy, colorectal and pancreatic cancer, are illustrated. Combined modality imaging is considered in gastric cancer based on the evolution of the classification of gastric lymph nodes. The role of sonography, endoscopic ultrasonography, spiral CT and MRI is assessed in gastric cancer N staging. A retrospective study is analyzed and perspectives for the application of a new CT protocol are proposed. PET potentialities in the study of abdominal lymph nodes are examined.  相似文献   
74.
Effect of Cholesterol Levels on Villous Histology in Colonic Adenomas   总被引:4,自引:0,他引:4  
To date no studies have examined the relationship between cholesterol levels and the occurrence of specific colonic polyp histologies. Villous histology has a greater predilection for subsequent malignancies than other histologies. Consequently, we examined the effect of cholesterol levels on the occurrence of villous adenomas. Just under one in 10 (9.5%, 15/158) patients had polyps with villous histologies. Cholesterol levels were positively and nonlinearly associated with a greater likelihood of villous histology, suggesting that a threshold exists for the effect of cholesterol level on the likelihood of having polyps with villous histology [odds ratios (OR) for combined two variable quadratic effect: cholesterol OR, 1.18; 95% confidence interval (CI), 1.02–1.37 and cholesterol squared OR, 1.004; 95% CI, 1.00–1.02]. Our data suggest that, in patients with polyps, higher cholesterol levels increase the likelihood of having polyps with villous histology, but that the effect of cholesterol level reaches a threshold.  相似文献   
75.
There have been only 58 angiographically documented reports of transmural myocardial infarction due to closed-chest trauma. None of these cases has been treated by percutaneous transluminal coronary angioplasty. We report the case of a 40-year-old man who developed an anterior-wall myocardial infarction secondary to blunt chest trauma suffered in an automobile accident. Angiographic study performed 2 months after the injury revealed an isolated total obstruction of the left anterior descending coronary artery. The patient was judged a good candidate for balloon angioplasty, but total reocclusion occurred within 24 hours of the procedure and a 2nd attempt did not restore patency. Surgical revascularization was performed a week later. A year after his injury, the patient remains asymptomatic and is back at work. Despite the failure of percutaneous transluminal coronary angioplasty in its 1st application to coronary artery repair after blunt chest trauma, we believe it to be the treatment of choice in young patients and in single-vessel disease.  相似文献   
76.
A trial of the efficacy of aspirin in the prevention of thrombotic occlusion of an "aortic loop" in rats was made simultaneously by two experimental surgeons. A relatively large dose of aspirin (80-100 mg/kg/day) was used, starting two days before operation. It appeared that aspirin was of limited benefit, reducing thrombotic occlusions by about 17% seven days after the insertion of the loop into the abdominal aorta. Although the average occlusion time was prolonged by about 17% in aspirin-treated animals, the separate trials gave no conclusive result. When the data from both operators were pooled, a statistically significant protection by aspirin was apparent (p = 0.02), by a two-tailed Student's t test. However, on using the powerful non-parametric randomization test, the occlusion times in control and aspirin-treated groups appeared not statistically different (p = 0.07). No significant difference was also found between control and treated groups when data were analyzed by X2 test. Independently of the statistical analysis, these data are quite similar to those obtained from aspirin trials in men surviving myocardial infarction. This finding points to the usefulness of the aorta loop as an animal model for arterial thrombosis.  相似文献   
77.
Six healthy male volunteers received aspirin (ASA) in a compressed (320 mg) and an enteric-coated (800 mg) formulation as single oral doses ten days apart. Ten plasma samples were obtained from each volunteer between 5 and 120 min after compressed ASA, and seven between 10 and 240 min after enteric-coated ASA. ASA was undetectable (less than 100 ng/ml) in plasma from three subjects receiving compressed ASA and two receiving the enteric-coated preparation. Plasma levels and kinetic parameters of salicylate were the same in subjects with undetectable and detectable ASA plasma levels. More than 98% inhibition of pre-drug serum TXB2 was noted in all samples collected one and four hours after either ASA preparation. TXB2 generation recovered on average by 3.5% at 24 hr with both preparations. Thus inhibition of platelet TXB2 generation occurred independently of the amount of ASA reaching the peripheral circulation. If this is due to inhibition of platelet function in the enterohepatic circulation followed by extensive first-pass deacetylation of ASA, vascular PGI2 synthesis could be spared. A better knowledge of the kinetic parameters of ASA for each of the formulations used in thrombosis prevention trials might help in solving the "aspirin dilemma".  相似文献   
78.
BACKGROUND: Unusual sites of metastasis to the parotid gland and face are reported in patients with colorectal cancer, but the localization to both sites at the same time has never been described so far. CASE REPORT: Here, we describe the case of a 76-year-old woman with a T3N1M0 G2 rectal adenocarcinoma, treated with preoperative chemoradiotherapy performed at suboptimal dosages due to unacceptable toxicity. At the end of the program, the re-staging demonstrated the presence of metastasis in both the left parotid gland and subcutaneously on the frontal region of her face while the primary locoregional tumour manifestation was radiologically down-staged (reduction in N staging from N1 to N0). The patient did not respond to any other treatment and died due to disease progression 15 months after the diagnosis. CONCLUSIONS: Metastatic tumours in the parotid gland are uncommon with a higher incidence of primary sites of the head and neck. Parotid involvement of rectal adenocarcinoma is also extremely rare, and concomitant involvement of both the parotid gland and the face was not previously described. In this case, we cannot rule out the hypothesis that the delay of surgical removal of the primary tumour and/or a specific action of concomitant chemoradiotherapy on the tumour cell phenotype could promote cancer cell spreading to unusual sites.  相似文献   
79.
The overall survival of patients with osteosarcoma of the extremity with localized disease has greatly improved in recent decades and today about half of them are long-term survivors (i.e. more than 10 years). Owing to the increased number of long-term survivors, late side effects of combined chemotherapy are more evident and have been better studied. Doxorubicin-induced cardiac toxicity is still an important and ominous side effect even if the percentage of affected patients is low. In this study, we report the incidence of clinically symptomatic cardiac toxicity induced by doxorubicin, in our series of 755 patients with localized osteosarcoma of the extremity, who had been treated from 1983 to 2000 with different protocols at our institution. Thirteen (1.7%) patients developed a clinically symptomatic cardiac toxicity (New York Heart Association class II-IV). Six of them died. Of the seven still alive, three needed a heart transplant. The case report of these 13 patients is described in detail. A higher incidence of cardiac toxicity was noted in women patients (eight women=2.5% and five men=1.1%). Cumulative dose and dose intensity (cumulative dose/week of treatment) are the most important risk factors in developing doxorubicin-related cardiomyopathy.  相似文献   
80.
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