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121.
Severe protein-calorie malnutrition is a major problem in many intensive care (ICU) patients, due to the increased catabolic state often associated with acute severe illness and the frequent presence of prior chronic wasting conditions. Nutritional support is thus an important part of these patient's management. Over the years, enteral nutrition (EN) has gained considerable popularity, due to its favorable effects on the digestive tract and its lower cost and rate of complications compared to parenteral nutrition. However, clinicians caring for ICU patients are often faced with contradictory data and difficult decision-making when having to determine the optimal timing and modalities of EN administration, estimation of patient requirements and choice of formulas. The purpose of this paper is to provide practical guidelines on these various aspects of enteral nutritional support, based on presently available evidence.  相似文献   
122.
Interventions for parvovirus B19 infection need to balance the low risk of infection at a population level with the potential for serious adverse outcome for particular groups, notably the fetus, people with haemoglobinopathies and the immunocompromised. This guidance aims to assist the local decision-making process to be as evidence-based as the available evidence allows.  相似文献   
123.
PURPOSE: To show how to progress from the deviation of the visual axis (provided the diagnosis of concomitant strabismus is certain) to the classification of the squint in one out of the different squint syndromes and consequently to adopt the appropriate therapeutic strategy. METHOD: Every sign correlated with the deviation contributes to progress step by step to the diagnosis of a given squint syndrome. The age on onset of strabismus, either convergent or divergent, and its characteristic, intermittent or constant, allow in a first step to evaluate the potential binocularity, as well in early as late (acquired) strabismus. The first group of early strabismus includes manifest infantile strabismus and microstrabismus. Both have abnormal binocularity. The possibility of functional amblyopia, angle variability and additional incomitances have to be investigated. Early intermittent strabismus keeping a potential normal binocularity are seldom. In the second group of late onset strabismus, retinal correspondence has to be investigated by correspondence tests and prism or bifocus compensation to distinguish between the two possible types (including the accommodative forms of strabismus), i.e. decompensated microstrabismus with abnormal binocularity or normosensorial strabismus with potential normal binocularity. In some cases potential binocularity may be initially uncertain and/or remain later on subnormal. RESULTS: As the result of this systematic approach, every cases of squint can be classified in one out of the different squint syndromes. Based on the precise diagnosis, the appropriate treatment can be carried out. The goals of treatment which can be reached in every syndrome are indicated. DISCUSSION: For an overall view of the squint syndromes a classification with two entrances are necessary, on the one hand early or late onset, on the other hand normal or abnormal binocular conditions. CONCLUSION: This approach of concomitant strabismus should serve as guide lines for clinical practice.  相似文献   
124.
PURPOSE: To evaluate preoperative characteristics and outcome of the treatment of recurrent cytomegalovirus (CMV) retinitis with the ganciclovir implant. METHODS: Records of 54 patients with acquired immunodeficiency syndrome and active, previously treated CMV retinitis who received a ganciclovir implant in one (n = 31) or both (n = 23) eyes were reviewed. Entry criteria included prior insertion and removal of an indwelling catheter or failure to respond to tolerated doses of ganciclovir and foscarnet. Preoperative factors that might correlate with outcome were analyzed, including demographic factors, duration of human immunodeficiency virus disease and CMV retinitis, indications for surgery, prior anti-CMV treatment, and extent of retinitis. RESULTS: Forty-six patients completed 1 month of follow-up and were analyzed for outcome. Thirty-one (67.4%) had inactive retinitis at 1 month vs 15 (32.6%) with active retinitis, and they received a mean of 23.5 +/- 22.9 weeks of preoperative ganciclovir vs 58.0 +/- 52.0 weeks in patients with active retinitis (P = .003). Involvement of more than 25% of retinal area by CMV retinitis was also correlated with activity at 1 month (P < .001). Patients who received implants because of lack of venous access had a median time to progression of 8.0 +/- 3.0 months vs 2.0 +/- 1.2 months for patients who had inadequate response or intolerance to intravenous medication (P = .073). Patients with 6 months or less vs more than 6 months of preoperative ganciclovir treatment had progression at a median time of 8.0 +/- 1.7 months vs 2.0 +/- 0.3 months, respectively (P = .016). CONCLUSION: Longer duration of preoperative ganciclovir or larger area of CMV retinitis correlates with lower success of ganciclovir implant therapy for recurrent retinitis.  相似文献   
125.
Metabolism and excretion of atorvastatin in rats and dogs.   总被引:1,自引:0,他引:1  
Atorvastatin (AT) is a second-generation potent inhibitor of 3-hydroxy-3-methylglutaryl-CoA reductase, clinically approved for lowering plasma cholesterol. Using a mixture of [D(5)/D(0)] AT and/or [(14)C]AT, the metabolic fate and excretion of AT were examined in rats and dogs following single and multiple oral doses. Limited biliary recycling was examined in one dog after a single dose of AT. AT-derived metabolites in bile samples were identified by metabolite screening of the [D(5)/D(0)] AT molecular clusters using tandem mass spectrometry. Bile was a major route of [(14)C] drug-derived excretion, accounting for 73 and 33% of the oral dose in the rat and dog, respectively. The remaining radioactivity was recovered in the feces; only trace amounts were excreted in urine. Radioactive components identified in rat and dog bile were the para- and ortho-hydroxy metabolites, a glucuronide conjugate of ortho-hydroxy AT, and unchanged AT. Two minor radioactive components were identified as beta-oxidation products of AT with one confirmed as a beta-oxidized AT derivative. The reappearance of AT and major metabolites in bile from a dog administered a sample of its previously excreted bile indicated biliary recycling is an important component in AT metabolism. Multiple dose administration in rats did not alter biliary metabolic profiles. Rat and dog plasma profiles after multiple dose administration were similar and showed no additional metabolites not found in bile. Examination of rat and dog bile and plasma indicates that AT primarily undergoes oxidative metabolism.  相似文献   
126.
Advances in our understanding of the molecular genetics of cancer present an opportunity to develop prevention and treatment strategies based on the reversal of specific genetic lesions. This strategy is analogous to the classic concept of gene therapy for replacement of defective or nonfunctioning genes. The gene families implicated in carcinogenesis include dominant oncogenes and tumor suppressor genes. Regional administration of viral vectors expressing wildtype p53 and antisense K-ras prevents tumor growth for tumors with the specific genetic lesions in orthotopic tumor models and mediates regression of large established tumors. These studies provide a rationale for a new clinical protocol recently approved by the National Institutes of Health Recombinant DNA Advisory Committee and Food and Drug Administration to replace a defective p53 gene with intratumor injection of recombinant retrovirus expressing wild-type p53 or elimination of activated K-ras by expression of antisense K-ras messenger RNA. If these agents are efficacious, their lack of toxicity may provide a sufficiently high therapeutic index such that they could be used as an adjuvant to surgery to treat patients with earlier stages of cancer or as prevention for second primary cancers for individuals with genetic abnormalities in premalignant lesions. Although much research needs to be done, the possibility of specific gene targeting with a high therapeutic index makes this a promising area of investigation.  相似文献   
127.

Purpose

We present a time and labor saving embedding technique for a full-thickness bowel flap tube used as a continent outlet.

Materials and Methods

In 17 patients the bowel flap tube was extramurally embedded instead of being submucosally tunneled. The reservoir was attached to the abdominal wall to reinforce the continence mechanism and prevent the tunnel from opening.

Results

All 17 patients are completely continent and 14 of 16 evacuate urine easily with a 14F catheter. Due to recurrent stomal stenosis 1 patient with severe diabetes has undergone incontinent diversion.

Conclusions

Our described tunneling procedure for the full-thickness bowel flap tube is easy to perform and provides excellent continence.  相似文献   
128.
Summary The effects of kainic acid lesions and chronic haloperidol treatment on rat striatal dopaminergic presynaptic receptors were studied. Following the -butyrolactone-induced inhibition of dopaminergic impulse flow, and after dopa decarboxylase inhibition, dopa accumulation and its reversal by dopamine agonists was measured in vivo.3H-apomorphine (a dopamine receptor ligand with purported presynaptic specificity) was used for in vitro binding experiments. Presynaptic dopamine receptors, as assessed by both methods, were unaffected by intrastriatal kainic acid injection 5–6 days before sacrifice. Seven days after termination of chronic haloperidol treatment (28 days, 0.5 mg/kg/day s.c.) both an increased apomorphine response using the dopa accumulation method and an increase in3H-apomorphine binding were observed, indicating the development of presynaptic dopamine receptor supersensitivity.  相似文献   
129.
130.
A case of sudden infant death after 15 minutes of successful resusciation of cardiovascular function is presented. While apnoic cranial nerve areflexia and electrocerebral silence persisted, angiography and transcranial Doppler sonography demonstrated nearly normal cerebral perfusion, which even increased day by day inspite of the persistence of other signs of brain death. The phenomenon cerebral reperfusion is concluded to be compatible with the diagnosis of brain death.  相似文献   
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