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61.
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63.
Hollingworth W Todd CJ Bell MI Arafat Q Girling S Karia KR Dixon AK 《Clinical radiology》2000,55(11):825-831
AIM: To provide information about the diagnostic and therapeutic impact of magnetic resonance imaging (MRI) and to compare the findings across diagnostic groups. MATERIALS AND METHODS: A prospective, observational study of 2017 consecutive referrals for MRI of the head, spine or knee at four imaging centres. Clinicians completed questionnaires before MRI stating initial diagnoses, diagnostic confidence and treatment plans. After imaging, a second questionnaire evaluated clinicians' revised diagnosis and treatment plans in the light of imaging findings. Patients were grouped into nine diagnostic categories for analysis. Comparison between pre- and post-imaging was used to assess the diagnostic and therapeutic impact of MRI. RESULTS: In seven of nine diagnostic groups MRI findings were associated with a diagnostic impact. Diagnoses were revised or discarded following normal MR findings and diagnostic confidence was increased by confirmative MR findings. There was no statistically significant diagnostic impact for suspected pituitary or cerebello-pontine angle lesions. In five of nine diagnostic groups (knee meniscus, knee ligament, multiple sclerosis, lumbar and cervical spine) MRI findings had a clear impact on treatment plans. CONCLUSION: This study demonstrates that in most diagnostic categories, MRI influences diagnosis and treatment. However, experimental studies are needed to prove that these diagnostic and therapeutic impacts lead to improved health.Hollingworth (2000). Clinical Radiology55, 825-831. 相似文献
64.
The clinical, radiographic, and morphological findings in 25 cases of atelosteogenesis and boomerang dysplasia have been
reviewed. The review confirms the nosologic grouping of atelosteogenesis type I with boomerang dysplasia and the clinical
and radiographic overlap of features between atel- osteogenesis I and atelosteogene- sis II (synonymous with De la Chapelle
dysplasia) and a group of patients with atelosteogenesis type III. A common pathogenesis is suggested for atelosteogenesis
type I and boomerang dysplasia. A marked excess of male fetuses with boomerang dysplasia was observed. Atelosteogenesis type
II shows distinctive chondro-osseous histopathology with a major disturbance in cartilage matrix macromolecules. An overlap
of phenotypic, radiographic, morphological, and cartilage histochemical features with those observed in diastrophic dysplasia
and achondrogenesis type IB suggests that atelosteogenesis type II has common pathogenetic features with disorders of sulfation
of connective tissue matrix macro- molecules.
Received/accepted: 8 December 1995 相似文献
65.
JE McMICHAEL 《Journal of paediatrics and child health》1997,33(1):1-3
An understanding of the neurodevelopmental outcome of long-term survivors of neonatal intensive care is essential for the informed management of preterm or high risk infants. This annotation looks at the current status of neonatal follow-up services in Australasia and highlights problems in the collection and interpretation of data. It suggests that we should work towards achieving a consensus on standard definitions and test regimes and on national data collection. 相似文献
66.
L Patel PE Clayton ME Jenney JE Ferguson TJ David 《Archives of disease in childhood》1997,76(6):505-508
Cross sectional studies have reported impaired growth in children with atopic dermatitis. If this growth impairment is irreversible, it would be expected to adversely influence final height attainment. The standing heights and other anthropometric parameters were assessed in 35 adults with onset of atopic dermatitis before 5 years of age and a control group of 35 adults with adult onset contact dermatitis or psoriasis. There was no significant difference in the standing height SD score, mid-parental height SD score, sitting height SD score, subischial leg length SD score, nor body mass index between the atopic dermatitis and control groups. The standing height SD score was not significantly different among: (a) patients with atopic dermatitis affecting less than 50% of their body surface area and those with greater than 50% affected; (b) patients using the four different potency topical corticosteroids; and (c) patients with atopic dermatitis without asthma and those with coexisting asthma. It is concluded that short stature is not a feature of our group of adult patients with onset of atopic dermatitis before 5 years of age, continuing into adulthood, and severe enough to require specialist care. This suggests that if growth impairment occurs in childhood, it is likely to be temporary and reversible. 相似文献
67.
The photodynamic response of two rodent tumour models to four zinc (II)-substituted phthalocyanines.
Four novel zinc (II)-substituted phthalocyanines, varying in charge and hydrophobicity, were evaluated in vivo as new photosensitizers for photodynamic therapy. Two rat tumours with differing vascularity were used: a mammary carcinoma (LMC1) and a fibrosarcoma (LSBD1), with vascular components six times higher in the latter (10.8%+/-1.5) than in the former (1.8%+/-1.4). Each sensitizer was assessed for tumour response relative to normal tissue damage, and optimum doses were selected for further study, ranging from 0.5 to 20 mg kg(-1). Interstitial illumination of the tumours was carried out using a 200-microm-core optical fibre with a 0.5 cm length of diffusing tip, at either 680 or 692 nm, depending on the sensitizer. Light doses of between 200 and 600 J were delivered at a rate of 100 mW from the 0.5-cm diffusing section of the fibre. Maximum mean growth delays ranged from 9 to 13.5 days depending on sensitizer and type of tumour, with the most potent photosensitizer appearing to be the cationic compound. Histopathological changes were investigated after treatment to determine the mechanism by which tumour necrosis was effected. The tumours had the appearance of an infarct and, under the conditions used, the observed damage was shown to be mainly due to ischaemic processes, although some direct tumour cell damage could not be ruled out. 相似文献
68.
69.
Both the exogenous administration of fibroblast growth factor-2 (FGF-2) or the induction of moderate hypothermia have been shown to attenuate histopathology and improve functional outcome after traumatic brain injury (TBI). Since combined therapeutic strategies may be more beneficial than single therapies, we examined the potential synergistic effect of FGF-2 combined with moderate hypothermia treatment induced 10 min after TBI on functional and histological outcome following controlled cortical impact (CCI) injury. Fifty male Sprague-Dawley rats were randomized to one sham and four CCI treatment groups: Sham+vehicle (VEH); FGF-2 (45 microg/kg/h for 3 h i.v.)+Normothermia (37+/-0.5 degrees C); FGF-2+Hypothermia (32+/-0.5 degrees C for 3 h); VEH+Norm; VEH+Hypo. Vestibulomotor performance on the beam balance and beam-walk (BW) tasks on post-operative days 1-5 and spatial memory acquisition in the Morris water maze (MWM) on days 14-18 were assessed. After 4 weeks survival, histological evaluations (CA(1) and CA(3) cell counts and lesion volume) were performed. MWM performance improved in all treatment groups, but combined treatment was not more efficacious than either alone. The FGF-2+Hypo group performed significantly better than the other injured treatment groups in the BW task. Lastly, no significant group differences in beam balance or histological outcome were observed. These data suggest a suboptimal and incomplete synergy of combined FGF-2 and hypothermia treatment. These data may indicate that either our dose of FGF-2 or combination therapy was not optimized in our model. 相似文献
70.
Mitch Dowsett Steve R Ebbs J Michael Dixon Anthony Skene Clive Griffith Irene Boeddinghaus Janine Salter Simone Detre Margaret Hills Susan Ashley Stephen Francis Geraldine Walsh Ian E Smith 《Journal of clinical oncology》2005,23(11):2477-2492
PURPOSE: To investigate the relationships between biomarker changes in breast cancer during neoadjuvant (preoperative) endocrine therapy. PATIENTS AND METHODS: The IMPACT trial compared the preoperative use of tamoxifen with anastrozole alone or in combination in postmenopausal women (n = 330) with primary breast cancer. Biomarkers were measured in tumor biopsy specimens taken at baseline, and after 2 and 12 weeks of treatment. RESULTS: 52 (93%) of 56, 46 (85%) of 54, and 37 (84%) of 44 patients in the anastrozole, tamoxifen, and combination groups, respectively. There was a significantly greater suppression of Ki67 in the anastrozole-treated group than in the tamoxifen- or combination-treated groups, which is parallel to the greater efficacy seen for anastrozole over these two treatments in the Arimidex, Tamoxifen, Alone or in Combination adjuvant trial. A positive relationship was noted between estrogen-receptor level and Ki67 suppression in all patients. Ki67 was reduced to a greater extent in progesterone receptor-positive tumors compared with progesterone receptor-negative tumors. HER-2-negative tumors tended to show a greater reduction in Ki67 compared with HER-2-positive tumors, but the difference was only significant in the tamoxifen group after 2 weeks, and in the anastrozole group after 12 weeks. CONCLUSION: These results confirm the value of Ki67 as a molecular marker, and provide information regarding the relationships between treatment-induced changes in Ki67 and other important biomarkers. Studies such as this should help integrate agents targeted at growth factor signaling with endocrine agents in breast cancer. 相似文献