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41.
Background Persistent or recurrent macular-sparing subretinal fluid (SRF) can sometimes occur following scleral buckling procedures. Observation and reoperation have been used in the management of such cases. Demarcation laser therapy (DLT) has been used to treat macular-sparing retinal detachments in the context of cytomegalovirus retinitis and as primary treatment for selected rhegmatogenous retinal detachments. There are, however, scarce data in the literature regarding its use following primary scleral buckling procedures. The current study explores the use of DLT under the latter circumstances.Methods The medical records of all consecutive patients with persistent SRF sparing the macula following primary rhegmatogenous retinal detachment repair using a scleral buckling procedure were retrospectively reviewed. Only those patients in whom the breaks were localised to the area of indentation and, thus, seemed to be well supported by the buckle were included. Demographics, clinical characteristics of the retinal detachment prior to scleral buckling, extension of the residual SRF observed postoperatively, details of the laser procedure, anatomical and functional outcomes and complications were evaluated.Results Seven patients, all females, with a mean age of 47.9 years (range: 20–81) were included in the study. The retinal detachments were superior (n=3), inferior (n=3) and subtotal, affecting both superior and inferior retina (n=1). Scleral buckling procedures were used to treat the retinal detachments in all cases. Following demarcation laser therapy, the area of SRF remained stable in two patients, and flattened in four. In one patient, extension of SRF occurred requiring further surgery.Conclusions Demarcation laser therapy appears to be a reasonable option in the management of patients with persistent or recurrent SRF sparing the macula following scleral buckling surgery.The authors do not have any proprietary interests in the products or methods utilised in this study  相似文献   
42.
The ultrastructure of the dorsal column nucleus (DCN) has been investigated at the level of the obex region in normal and experimental toads. Large 'isolated' neurons (greater than 20 micrometer) and clusters of small neurons (less than 20 micrometer) have been identified in this region. Synaptic profiles have been classified into three types: large 'en passant' LR boutons, containing round synaptic vesicles and neurofilaments, small R boutons with round vesicles and F boutons with pleomorphic vesicles. The axon terminals exhibited synaptic contacts with cell somata, with dendrites of varying calibers and with other axons. The terminals involved in the axo-axonic contact were the F boutons which were presynaptic to the LR boutons, thus representing the morphological basis for presynaptic inhibition. Transection of the second dorsal root was performed in order to identify the terminals of the primary afferents to the DCN, after different survival periods (16 h--50 days). Only the LR boutons underwent degeneration, thus representing the central endings of the primary dorsal root afferents. The functional significance of these findings was discussed.  相似文献   
43.
Trypanosoma cruzi, the etiological agent of Chagas disease, occurs as different strains or isolates that may be grouped in two major phylogenetic lineages: T. cruzi I, associated with the sylvatic cycle and T. cruzi II, linked to the human disease. In the mammalian host the parasite has to invade cells and many studies implicated the flagellated trypomastigotes in this process. Several parasite surface components and some of host cell receptors with which they interact have been identified. Our work focused on how amastigotes, usually found growing in the cytoplasm, can invade mammalian cells with infectivities comparable to that of trypomastigotes. We found differences in cellular responses induced by amastigotes and trypomastigotes regarding cytoskeletal components and actin-rich projections. Extracellularly generated amastigotes of T. cruzi I strains may display greater infectivity than metacyclic trypomastigotes towards cultured cell lines as well as target cells that have modified expression of different classes of cellular components. Cultured host cells harboring the bacterium Coxiella burnetii allowed us to gain new insights into the trafficking properties of the different infective forms of T. cruzi, disclosing unexpected requirements for the parasite to transit between the parasitophorous vacuole to its final destination in the host cell cytoplasm.  相似文献   
44.
A large number of school-aged children present with motor-based performance problems that have significant negative effects on their ability to participate fully in the daily activities of home, school, and play. These children have a neurodevelopmental disorder most commonly known as developmental coordination disorder (DCD). These children are frequently brought to the attention of the family doctor and referred to health care professionals in search of answers and services. Therapists treating these children have a large number of intervention approaches at their disposal. This paper presents an overview of these approaches and a review of the available evidence. The evidence for the older, deficit-oriented approaches remains inconclusive, at best; whereas the task-oriented approaches, seem to be better supported. While more work is needed to validate the use of the task-oriented approaches, the results suggest that a shift in perspective from a deficit-oriented to a task-oriented perspective would be appropriate.  相似文献   
45.
46.
Identifying rodent hantavirus reservoirs, Brazil   总被引:1,自引:0,他引:1  
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47.
48.
In the past decade, different modalities of antiviral therapy have been adopted aimed at eradicating hepatitis C virus infection. Initially, interferon was used in monotherapy, then interferon combined with ribavirin and amantadine. Recently, interferon has been conjugated with polyethylene glycol to allow optimization of its pharmacokinetic properties and to improve its antiviral activity. This study focused on the characteristics of the skin reactions that we observed in 27 patients with na?ve hepatitis C who received polyethylene glycol interferon-ribavirin-amantadine or polyethylene glycol interferon-ribavirin and in 10 previous non-responders to interferon monotherapy who were retreated with triple therapy. In 9 patients (7 on triple therapy) dermatitis-like lesions were observed, and in 5 the severity of the lesions necessitated withdrawal from therapy.  相似文献   
49.
Glatiramer acetate (copolymer 1, Copaxone) is a mixture of synthetic polypeptides and is used for the treatment of multiple sclerosis. It has been shown to possess beneficial effects in reducing the relapse rate in relapsing-remitting multiple sclerosis. Its main mechanism of action is regarded as a switch of the immune reaction from a T helper (Th)1 to a Th2 cell type. Glatiramer acetate is administered by subcutaneous injection once daily. As described in previous reports, the most common adverse effects are pain, inflammation, and induration at the injection site, occurring in approximately 20-60% of patients. A rare adverse effect is a localized lipoatrophy at the site of injection, which has previously been observed and described in 11 patients. It has been reported that these atrophic areas remain unchanged and localized lipoatrophy may be preceded by a subcutaneous panniculitis. In this article, we describe another case of subcutaneous changes following repeated glatiramer acetate injection, presented as localized panniculitis in the area around the injection sites, in a 46-year-old female patient who was treated with glatiramer acetate for 18 months.  相似文献   
50.
OBJECTIVE: Our purpose was to assess the effects of the adjunctive use of cardiovascular dynamics monitoring in the ambulatory management of 199 pregnant patients with severe hypertension. STUDY DESIGN: A prospective, observational study was performed. Determinants of mean arterial pressure were computed by using the Hon monitor. Indicators of arterial compliance and effective blood volume were developed. All patients were monitored in the outpatient clinic; additionally, 19 patients self-tested at home. No rigid medication protocol was followed, but furosemide was used in most cases when cardiovascular dynamics monitoring patterns were consistent with volume loading. Otherwise, vasodilators were prescribed. The t test for independent samples was used to compare the home-monitored subgroup with the outpatient-only group. RESULTS: Pregnancy was prolonged by 74 +/- 63.9 days (mean +/- SD). Mean gestation was 37.6 +/- 2.9 weeks, and mean birth weight was 2882.4 +/- 837 g. The primary cesarean delivery rate was 23.7%, but only 15 (7.5%) cesarean deliveries were performed because of failed therapy. The 19 home-monitored patients gained 108 +/- 75 days (83.1 +/- 42.2 days beyond 20 weeks). CONCLUSION: Adjunctive cardiovascular dynamics monitoring may have a role in the evaluation and management of hypertension during pregnancy.  相似文献   
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