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81.
Ho  CP; Kim  RW; Schaffler  MB; Sartoris  DJ 《Radiology》1990,176(1):171-173
Dual-energy radiographic absorptiometry (DRA) was used to measure the bone mineral content and area density of lumbar vertebrae (L2-L3) in 11 cadavers. These data were subsequently compared with measured ash content and density. Excellent correlation was obtained between bone mineral content measured with DRA and ash weight (r = .963, P less than .0001). The accuracy error in determining mineral content in lumbar vertebrae with DRA was about 9%. In addition, strong correlation was observed between bone mineral density measured with DRA and ash density (r = .881, P less than .0001).  相似文献   
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83.
Adenomyoepithelioma is a rare disorder characterised by simultaneous proliferation of ductal epithelium and myoepithelial cells. It is more common in salivary glands or skin, and only rarely found in breast tissue. Adenomyoepithelioma of the breast was first described in 1970 by Hamperl.1 Since then, approximately 55 cases have been described in the literature; the largest review, by Tavassoli in 1991, reported 27 of these cases.2 Because of the small number of cases reported, the natural history of adenomyoepithelioma of the breast remains uncertain. We report a further case which was treated by local excision, and follow-up for two years has revealed no evidence of local recurrence or metastatic spread.  相似文献   
84.
The T(c)-cell response to ectromelia virus infection was studied in BALB/c-H-2(db) mice which carry a loss mutation in the H-2D region that results in the absence from cell surfaces of a molecule (D’) bearing certain public H-2 specificities. When infected, these mice showed a poor response of T(c) cells that recognize H-2D(d) plus virus-specific determinants on infected macrophage targets, but gave a normal response to H-2K d plus virus-specific antigens. However, their own infected macrophages do display wild-type antigenic patterns involving virus and H-2D(d) since they were killed as efficiently as wild-type (BALB/c,H- 2(d))-infected cells by T(c) cells specific only for H-2D(d) plus viral antigens. When tested in vitro, infected BALB/c-H-2(db) cells stimulated a poor T(c)-cell response to H-2D plus virus-specific antigens, but stimulated a normal response (in comparison with infected BALB/c macrophages) to H-2K(d) plus viral antigens. Uninfected BALB/c-H-2(db) cells stimulated a normal T(c)-cell response to minor H antigens or trinitrophenyl in association with H-2D(d), thus suggesting that the defective response to infection may reside in a failure of the relevant H-2D(d) antigens of mutant cells to physically associate with viral antigens. Close association of viral and H-2D-coded molecules was also suggested by ability of specific anti-H-2K or -H-2D to partially block T(c)-cell-mediated lysis of infected targets. These results were interpreted to mean that H-2Dd-dependent, virus- immune T(c) cells recognized an antigenic pattern consisting of virus- specific and H-2D(d) determinants with the latter borne on an H-2D molecule carrying serologically-defined H-2D(d) private specificities. A second H-2D(d)-coded molecule (D’) was not required for recognition and lysis by activated T(c) cells, but was apparently necessary for efficient stimulation of precursor T(c) cells, perhaps by promoting appropriate physical association of viral and H-2D(d) molecules.  相似文献   
85.
To understand better the relationships between blood-group antigens and bacterial constituents, examples of 23 gram-negative bacteria (representing the 10 genera Citrobacter, Edwardsiella, Enterobacter, Escherichia, Klebsiella, Proteus, Pseudomonas, Salmonella, Serratia, and Shigella) were tested for the presence of Kl-like antigens by hemagglutination-inhibition (HAI) assays against both IgG and IgM anti-Kl. Saline-suspended whole organisms, cell-free culture media, and disrupted organisms were used to test for such antigens in, on, and secreted by the microorganisms examined. Disrupted organisms of an isolate of Shigella sonnei nonspecifically inhibited IgG anti-Kl as well as IgG antibodies of the specificities Kpb, Fya, S, and c. However, only Escherichia coli 0125:B15, subtype 12808, had specific K1-like activity (no activity with other IgG [(k, Kpb, Jka, Fya, S, c] and IgM [A, B, M, P1] antibodies). Disrupted organisms inhibited IgM but not IgG anti-K1 in the HAI assay. A second subtype, E. coli 0125:B15, subtype 12809, exhibited no K1-like activity. These findings support the report of K1 activity in cell-free broth cultures of E. coli 0125:B15 (subtype unspecified). Thus, although not all E. coli 0125:B15 possesses K1-like activity, the finding of such activity in at least one E. coli subtype confirms the idea that bacterial components may play a role in the production of naturally occurring antibodies directed against non-ABO red cell antigens.  相似文献   
86.
Although fractures of the clavicle are common, complications are rare. A 41 year old painter developed two uncommon complications of clavicular fracture, mechanical intermittent subclavian artery occlusion and subclavian vein thrombosis. Both conditions were clearly identified on the clinical symptoms and signs and confirmed with dynamic angiography and computerised tomography. Operative intervention led to complete resolution of symptoms.  相似文献   
87.
胚胎嗅鞘细胞移植治疗脑性瘫痪:4例术后4周结果报告   总被引:7,自引:3,他引:7  
目的:观察胚胎嗅鞘细胞移植治疗脑性瘫痪的有效性和安全性。方法:①病例资料:4例因出生时缺血缺氧确诊为脑性瘫痪的患者,男2例,女2例,年龄分别为14岁、岁、个月、岁。嗅92817鞘细胞由北京市虹天济神经科学研究院细胞中心提供,实验经医学伦理委员会批准,4例脑性瘫痪患者均签署知情同意书。②实验方法:根据术前MRI或CT片,患者均在局麻下行微创立体定向嗅鞘细胞移植术,选取双额放射冠为注射靶点,每侧注射1.0×106个细胞。术后给予止血、抗感染、康复等常规处理。③实验评估:分别于嗅鞘细胞移植前、移植后4周采用脑瘫综合功能评定量表、脑瘫日常生活能力量表评价患者神经功能及生活质量的改善。结果:①嗅鞘细胞移植术后4周,4例患者较术前均有不同程度的神经功能改善,未出现手术并发症。②脑瘫综合功能评定总分:病例1由92.5分增至94分,病例2由55分增至56分,病例3由10.5分增至11.5分,病例4由9.5分增至13分。③脑性瘫痪日常生活能力量表总分:病例1由82.0分增至83.5分,病例2无变化,为16.5分,病例3由5.0分增至7.5分,病例4由5.0分增至8分。结论:嗅鞘细胞移植治疗脑性瘫痪患者近期评价安全可行,可部分改善神经功能与生活质量,长期效果有待进一步随访。  相似文献   
88.
We compared responses to amoxicillin combined with clavulanic acid (ACA) with a cefaclor regimen in children with skin and soft tissue infections (impetigo and cellulitis) due to Staphylococcus aureus, Streptococcus pyogenes, and Haemophilus species. All isolates from the 41 patients we were able to evaluate were susceptible to ACA by disk susceptibility testing at the onset of treatment. The 21 children receiving ACA and 18 (90%) of 20 taking cefaclor responded to therapy. Clinical cure was achieved in 18 (86%) of 21 and 18 (90%) of 20 in the two groups, respectively. Bacteriological failure occurred in 2 (10%) patients in the cefaclor group and none in the group receiving ACA; however, there were 2 (9%) relapses and 1 (5%) reinfection among the 21 children taking ACA. Adverse effects, although mild, occurred more commonly (9 of 21 versus 1 of 20; P = 0.005) with ACA than with cefaclor.  相似文献   
89.
In Australia, the legal basis for the detention and restraint of people with intellectual impairment is ad hoc and unclear. There is no comprehensive legal framework that authorises and regulates the detention of, for example, older people with dementia in locked wards or in residential aged care, people with disability in residential services or people with acquired brain injury in hospital and rehabilitation services. This paper focuses on whether the common law doctrine of necessity (or its statutory equivalents) should have a role in permitting the detention and restraint of people with disabilities. Traditionally, the defence of necessity has been recognised as an excuse, where the defendant, faced by a situation of imminent peril, is excused from the criminal or civil liability because of the extraordinary circumstances they find themselves in. In the United Kingdom, however, in In re F (Mental Patient: Sterilisation)11. In re F (Mental Patient: Sterilisation) [1990] 2 AC 1.View all notes and R v Bournewood Community and Mental Health NHS Trust, ex parte L,22. R v Bournewood Community and Mental Health NHS Trust, ex parte L [1999] 1 AC 458.View all notes the House of Lords broadened the defence so that it operated as a justification for treatment, detention and restraint outside of the emergency context. This paper outlines the distinction between necessity as an excuse and as a defence, and identifies a number of concerns with the latter formulation: problems of democracy, integrity, obedience, objectivity and safeguards. Australian courts are urged to reject the United Kingdom approach and retain an excuse-based defence, as the risks of permitting the essentially utilitarian model of necessity as a justification are too great.  相似文献   
90.
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