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BACKGROUND: Measurement of muscle mass is useful for evaluating protein nutritional status. Various methods for estimating muscle mass in haemodialysis patients have recently been developed. METHODS: The validity of the estimate of creatinine production calculated with the creatinine kinetic model (CKM) was examined in 46 haemodialysis patients by comparing it with the actual creatinine production, this being determined from the sum of creatinine appearing in the dialysate and the estimated metabolic degradation. The correlation of various other muscle mass indices with creatinine production was also investigated in these patients. RESULTS: The estimate of creatinine production using CKM was significantly correlated with creatinine production calculated from the spent dialysate plus an estimate for the extra-renal creatinine degradation (r=0.90, P<0.001). A Bland-Altman analysis revealed that the mean prediction error for the estimate of creatinine production by CKM was +0.10 g/day and the limits of agreement were +0.34 to -0.14 g/day. The cross-sectional area of the thigh muscle measured by computed tomography (CT) was also significantly correlated with creatinine production (r=-0.86, P<0.01). In contrast, the correlations of 3-methylhistidine production measured in the spent dialysate, the mid-upper arm muscle circumference and the skeletal muscle mass estimated by an anthropometric prediction model with creatinine production were lower (r<0.82). CONCLUSION: Creatinine production calculated using CKM and CT measurement of thigh muscle area are valid methods for estimating muscle mass during routine clinical examinations of haemodialysis patients.  相似文献   
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In order to investigate whether intravenous bolus injection of isosorbide dinitrate (ISDN) is a safe and efficient therapy in aged patients with congestive heart failure, we studied acute hemodynamic effects in 11 patients. Peak effects on preload were observed after 5 to 10 minutes of bolus injection and unloading effects continued effectively for 60 minutes. At peak effect, pulmonary systolic pressure decreased from 50.2 +/- 2.6 to 36.2 +/- 2.6 mmHg (-28.5%, p less than 0.01) and pulmonary end diastolic pressure decreased from 25.0 +/- 2.2 to 18.5 +/- 2.1 mmHg (-26.0%, p less than 0.01). Mean pulmonary artery wedge pressure decreased from 23.4 +/- 2.2 to 16.0 +/- 2.1 mmHg (-31.6%, p less than 0.01). Mean right atrial pressure decreased from 10.5 +/- 1.8 to 7.4 +/- 2.0 mmHg (-29.5%, p less than 0.01). Blood pressure, heart rate, cardiac index, systemic and pulmonary vascular resistance showed no significant changes. Thus, intravenous bolus injection of ISDN showed a potent vasodilator effects on preload, and may be a safe and useful treatment for aged patients with acute congestive heart failure.  相似文献   
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Uterus didelphys with unilateral imperforate vagina is rare. Interestingly, in all reported cases in which the urinary tract was investigated renal agenesis was found on the side of the obstructed hemivagina. We report 2 cases of this unusual and interesting condition, and review the embryogenesis of müllerian duct abnormalities associated with renal agenesis, as well as the clinical findings, diagnosis and management. We stress the importance of prompt and accurate diagnosis, and treatment as a means to avoid unnecessary surgical procedures.  相似文献   
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Immunization with an inactivated whole-virus vaccine is highly effective in preventing lentivirus infection. The viral protein(s) essential to the induction of protective responses, however, have not been identified. To define the role of virion components in the induction of protective immunity, we evaluated the efficacy of glycoprotein-enriched and glycoprotein-depleted simian immunodeficiency virus (SIV) subunit vaccines prepared by lentil-lectin affinity chromatography of gradient-purified virions using the immunization and challenge regimen previously found successful with an inactivated whole-virus vaccine. Infection was determined by successful recovery of virus, the induction of SIV-specific antibody responses, and infection of naive recipients by inoculation with lymph-node-derived lymphocytes from the vaccinates. Immunization with the glycoprotein-enriched preparation prevented infection in two out of four monkeys, whereas the glycoprotein-depleted vaccine failed to prevent infection in all four vaccinates tested. However, the glycoprotein-depleted vaccine appeared to moderate the progression of SIV-induced disease compared with non-immunized infected control monkeys inoculated with the same challenge dose. These data suggest that subunit vaccines containing sufficient quantities of viral glycoproteins can protect against SIV infection, whereas subunit vaccines composed predominantly of viral core proteins cannot. The development of effective vaccines against HIV infection should include studies on the optimum presentation of the viral envelope glycoproteins to produce long-term broadly protective immune responses.  相似文献   
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Three-dimensional fast asymmetric spin echo (3D FASE) cisternography provides high spatial resolution and excellent contrast as a water image acquisition technique. It is also useful for the evaluation of various anatomical regions. This study investigated the usefulness and limitations of virtual endoscopic images obtained by 3D FASE MR cisternography in the preoperative evaluation of patients with neurovascular compression. The study included 12 patients with neurovascular compression: 10 with hemifacial spasm and two with trigeminal neuralgia. The diagnosis was surgically confirmed in all patients. The virtual endoscopic images obtained were judged to be of acceptable quality for interpretation in all cases. The areas of compression identified in preoperative diagnosis with virtual endoscopic images showed good agreement with those observed from surgery, except in one case in which the common trunk of the anterior inferior cerebellar artery and posterior inferior cerebellar artery (AICA-PICA) bifurcated near the root exit zone of the facial nerve. The veins are displayed in some cases but not in others. The main advantage of generating virtual endoscopic images is that such images can be used for surgical simulation, allowing the neurosurgeon to perform surgical procedures with greater confidence.  相似文献   
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Thoracic outlet syndrome is a disorder caused by neurovascular compression of the brachial nerve plexus and the subclavian artery or vein by bones and muscles. We report the MR angiographic findings of a patient with thoracic outlet syndrome.  相似文献   
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We report a case of benign osteoblastoma arising in the temporal bone of a 28-year-old woman. Plain radiography showed a mass with an amorphous calcified matrix and a thin radiolucent marginal zone. CT and MR imaging were useful in delineating the extent of the tumor, and angiography showed its hypervascularity. Preoperative transarterial embolization was effective in reducing bleeding during surgery.  相似文献   
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The clinical features of congestive heart failure in the elderly were investigated in 104 patients (57 males, 47 females, mean age of 79.2). Patients were divided into two subgroups, the readmission group, 33 patients who were readmitted within 6 months after discharge, and the non-readmission group. Chief complaints were dyspnea, edema, chest pain, loss of appetite, chest compression, and palpitation. Heart failure was caused by infection, myocardial ischemia, arrhythmia, inappropriate drug usage including poor drug compliance, the use of beta-blockers, excessive intake of sodium, and anemia. Careful use of drug was essential especially in the readmission group. Major underlying heart disease were ischemic heart disease (39.4%), valvular disease (26.9%), hypertensive heart disease (9.6%), with cardiomyopathy, congenital heart disease seen in the minority. There was no statistically significant difference in underlying heart diseases between the two groups. Supraventricular arrhythmias such as atrial fibrillations, paroxysmal atrial fibrillations, paroxysmal supraventricular tachycardias, and premature atrial contractions were noted in 85.3% of the cases. Drugs for treatment were diuretics, digitalis, isosorbide dinitrate, calcium antagonists. ACE inhibitors and alpha-blockers were also used, showing that vasodilators were more extensively used than before. The major complications were hypertension (39.4%), renal dysfunction (27.9%), cerebrovascular disease (26.9%), diabetes mellitus (16.5%), arteriosclerosis obliterans (7.7%). Renal dysfunction, arteriosclerosis obliterans was seen significantly more frequently in the readmission group. The prognosis at one year after admission was significantly worse in the readmission group. In summary, the major underlying diseases were ischemic heart disease, valvular disease, and hypertensive heart disease. Ischemic heart disease was seen more frequently than in previous investigations at our hospital.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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