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991.
Indium-111-labeled monoclonal antimyosin Fab has been used to image myocardial infarction, myocarditis and cardiac transplant rejection with localization in myocytes that have suffered irreversible loss of cell membrane integrity. Technical factors potentially limiting clinical usefulness of 111In antimyosin include dosimetry (72 hr half-life of 111In), slow blood clearance of antibody proteins delaying optimal imaging to 24 to 48 hr postinjection and nontarget organ uptake. Therefore, two new antimyosin imaging agents experimentally shown to potentially improve dosimetry, shorten time from injection to imaging or decrease nonspecific cell binding were evaluated in a primate cardiac transplant model. The two agents evaluated were polylysine 111In-antimyosin (0.023 mg Fab modified with a 3.3 kd polymer of polylysine and labeled with 111In) and 99mTc-antimyosin (0.5 mg Fab' antimyosin labeled using the RP-1 ligand technique). A total of eight baboons were studied: three with heterotopic (cervical) xenographs, three with orthotopic allographs and two control animals. Each animal was injected first with 12-23 mCi of 99mTc-RP-1 antimyosin and 5-16 hr after completion of imaging, was injected with 0.72-1.88 mCi of 111In-polylysine antimyosin (PIs) and reimaged 12-48 hr later. The imaging results were compared to the histology of the animals. Biexponential curves were fit to the blood sample data and rate constants were determined and expressed as T1/2 values. There were no significant differences between the two agents in either the early fast components or the late slow components. On planar imaging, there was blood-pool activity at 10-12 hr postinjection of both agents, but by 16-24 hr postinjection, blood pool was negligible on the 111In-PIs scans. Both agents were concentrated in the rejected cardiac tissue. The slow blood-pool clearance combined with the 6 hr half-life of 99mTc-RP-1 AMA make this agent less promising for detection of diffuse myocardial uptake than 111In Fab modified with polylysine.  相似文献   
992.
Repetitive transcranial magnetic stimulation (rTMS) can produce long-lasting effects not only underneath the site of stimulation, but also at distant connected sites. This study aimed to assess how low frequency rTMS over the premotor area might affect abnormalities in spinal motor function in patients with generalised dystonia associated with the DYT1 gene mutation. We assessed reciprocal inhibition (RI) in a group of 8 manifesting carriers of the DYT1 gene (DYT1) and 10 healthy controls. All subjects then received 20 minutes of 1 Hz rTMS over the premotor area, and RI was assessed again. Before rTMS, the second and third phases of RI were abnormal in DYT1 subjects compared to controls. After 20 minutes of 1 Hz rTMS over the premotor area, a significant increase in inhibition was noted in the third and possibly the first phase of RI in the DYT1 group. No changes in RI were observed in control subjects after rTMS. We have shown for the first time to date that reducing cortical excitability in patients with dystonia using rTMS can produce corresponding changes in abnormal spinal motor output. These findings make a case for further exploring rTMS as a tool to modulate abnormal cortical and spinal excitability in individuals with dystonia and even as a potential form of treatment for dystonic symptoms.  相似文献   
993.
Efficacy of oral oxpentifylline in the management of idiopathic tinnitus   总被引:1,自引:0,他引:1  
A prospective single-blind, placebo-controlled trial was effected in 30 patients presenting to an out-patient clinic complaining principally of tinnitus. Over a 6-week period, the subjects were assessed by routine audiometry and subjective reporting of change in their symptoms. A treatment group received the xanthine derivative, oxpentifylline (Hoechst UK), while a control group received identically presented inactive placebo. There was no significant difference between the placebo and treatment groups for any of the parameters measured, and, therefore, oxpentifylline cannot be recommended in the management of idiopathic tinnitus.  相似文献   
994.
A clinical study was done on 48 eyes to assess the role of an indigenous drug, Saptamrita Lauha, in the absorption of hemorrhages and prevention of their recurrence in retinopathic eyes. Rapid absorption of retinal hemorrhages was observed in both treated groups: diabetic and hypertensive (mean durations, 16 days and 17.83 days, respectively). In three eyes, the hemorrhage cleared completely; partial clearance was observed in the rest of the eyes. Recurrence of a hemorrhagic episode was less in treated eyes (25% in each group) compared with control eyes (60% in diabetic and 50% in hypertensive patients). This study suggests that Saptamrita Lauha may hasten the process of retinal hemorrhage absorption and prevent its recurrence. The beneficial effect could be attributed to the flavanoid-like properties of one of the ingredients of this natural product.  相似文献   
995.
996.
V Bhatia  J I Wolfsdorf 《Pediatrics》1991,88(6):1187-1193
Hypoglycemia is the most common acute complication of insulin-dependent diabetes mellitus, yet data are sparse concerning its frequency and the factors that predispose children and adolescents to its occurrence. This study was undertaken, during a 2-year period, to determine the frequency of severe hypoglycemia and to identify its causative factors in 196 youth with insulin-dependent diabetes mellitus (mean age and duration of diabetes, 13.5 +/- 4.3 and 4.8 +/- 3.2 years, respectively) treated conventionally. The mean daily insulin dose was 0.85 +/- 0.23 U/kg, and 92% of patients received insulin twice daily. Severe hypoglycemia occurred at least once in 2 years in 29 of 196 (14.8%) patients, of whom 9 (31%) had two or more episodes. The mean level of glycosylated hemoglobin closest to the event was significantly lower than that of patients who did not have severe hypoglycemia, 10.6 +/- 1.8 vs 11.4 +/- 2.0, P less than .02; however, the mean insulin dose, 0.88 +/- 0.19 vs 0.85 +/- 0.23 U/kg every 24 hours, was similar. Severe hypoglycemia occurred with equal frequency during waking and sleeping, and it was not related to the species of insulin used. The use of human insulin, per se, did not increase the risk of severe hypoglycemia. Asymptomatic hypoglycemia was reported significantly more often in those who experienced severe hypoglycemia, 24% vs 8%, P = .01. Severe hypoglycemia was common (12.2 episodes per 100 patient-years), and symptomatic hypoglycemia universal in youth with insulin-dependent diabetes mellitus treated with conventional insulin therapy. Approximately two thirds of episodes were attributable to lapses in the application of basic principles of diabetes self-care.  相似文献   
997.
We studied 285 children (aged 1–15 yrs) attending a psychiatric and child guidance clinic over the period of one year (Jan 1985 to Feb 1986). Majority of children belonged to lower social class III & IV (73.4%) and unitary family (65.6%). There was male predominance (72.3%). Maximum psychiatric morbidity was observed in age group 5–9 years. Main psychiatric problems noted were neurosis (21.1%) and eating disorders (23.2%). Amongst neurosis, the commonests was hysteria (61.7%),followed by phobia (31.7%) and anxiety neurosis (6.6%). Aches and pains (51.4%) and school phobia (47.4%) were the main presenting feature of hysteria and phobia respectively. Stress of examination and failure (16.1%) and quarrels with peers, siblings or parents (13.0%) were observed to be the main precipitating factors.  相似文献   
998.
999.
We describe two female patients, 66 and 36 years of age, with both primary hyperparathyroidism and chondrosarcoma. Case 1 had a chondrosarcoma of the right scapula, and case 2 had chondrosarcoma of the left proximal tibia. Both patients underwent surgical resection of their chondrosarcoma and subsequent parathyroid surgery. Histological analysis of the excised parathyroid in case 1 showed a parathyroid carcinoma and in case 2 showed a parathyroid adenoma. Including these two patients, there is now a total of six cases that have been reported in the literature describing the association between hyperparathyroidism and bone malignancy. We believe that this small number makes it unlikely that there is an association between these two conditions, although we speculate that there may be an underlying genetic basis.  相似文献   
1000.
This Study deals with determination of viability by FDA-EB method. It has been observed that some of the bacilli do not take any colour in FDA-EB preparations. These can be called "neither green nor red" (NGR) bacilli. These non-staining bacilli should be taken into account when reporting viability by FDA-EB method.  相似文献   
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