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991.
In unselected patients with intractable temporal lobe epilepsy (TLE), approximately 15% do not have detectable hippocampal atrophy on MRI. The purpose of this study was to evaluate whether T2 relaxometry can identify hippocampal pathology and lateralize the epileptic focus in patients with intractable TLE, who do not demonstrate hippocampal atrophy on volumetric MRI (MRIV). We selected 14 patients with unilateral TLE who had unilateral atrophy and 11 patients with unilateral TLE who had no evidence of atrophy on MRIV. Images were acquired on a 1.5 T MR scan using a dual echo sequence with 23 contiguous oblique coronal slices in all patients and in 14 healthy subjects. Fitting a single exponential decay equation to the imaging data generated T2 maps. Averages of six slices containing the head, body, and tail of the hippocampus were used to calculate hippocampal T2 relaxation times (HT2). The epileptic focus was defined by history, video-EEG, and surgical response. All TLE patients with hippocampal atrophy and 9/11 (82%) patients with normal MRI had abnormally high HT2 ipsilateral to the epileptic focus. Bilateral abnormal HT2 were found in 6/14 (43%) of patients with unilateral hippocampal atrophy and 2/11 (18%) of patients with normal MRI. However, this increase was always greater ipsilateral to the epileptic focus. Qualitative hippocampal pathology showed gliosis and neuronal loss in 10/14 operated patients with hippocampal atrophy on MRIV and in 5/7 operated patients with normal MRI. In conclusion, hippocampal T2 mapping provides evidence of hippocampal damage in the majority of patients with intractable TLE who have no evidence of atrophy on MRI and can correctly lateralize the epileptic focus in most patients.  相似文献   
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Besides routine postoperative follow-up the prophylaxis of complications in penetrating keratoplasty (PKP) includes special preoperative and intraoperative aspects. Preoperative prophylaxis consists of the therapy of systemic diseases and eyelid abnormalities, determining individual optimal graft size, avoiding PKP in cases of uncontrolled intraocular pressure, avoiding PKP in cases of corneal hydrops, pretreatment of vascularized cornea, amniotic membrane transplantation before PKP in cases of ulcerative keratitis, quality controlled organ-cultured transplants and preoperative counselling by the surgeon to ensure patient compliance. Intraoperative prophylaxis consists of controlled arterial hypotension and complete relaxation during general anesthesia, avoidance of decentration, horizontal torsion and vertical tilt using a non-contact trephination technique (preferably excimer laser) with double-running cross-stitch sutures and application of Flieringa rings in aphakic vitrectomized eyes. Postoperatively, periodical control examinations using fluorescein and blue light are indispensable. All loose sutures have to be removed as early as possible. In cases of herpetic eye disease 2?×?400 mg of oral acyclovir should be administered for at least 1 year. In cases of therapy-resistant epithelial defects 100?% autologous serum eyedrops or amniotic membrane patches are valid options. Immune reactions must be diagnosed and treated immediately with high doses of corticosteroids.  相似文献   
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Objective: To ascertain whether insulin‐like growth factor 1 (IGF1) is associated with retinopathy of prematurity (ROP) and is a useful predictor of the disease. Although its aetiopathogenesis is multifactorial, development of the disease appears to be related to a deficiency in IGF1, a hormone that acts together with vascular endothelial growth factor in the normal angiogenesis in the retina. Design: Prospective study for a 30‐month period. Participants: A total of 74 premature newborn babies, of less than 1500 g and/or 32 weeks’ gestational age or less. Testing: To determine the development and severity of ROP. Main outcome measures: Serum levels of IGF1 were measured once a week from birth until 40 weeks corrected gestational age in each subject. Results: Of our subjects, 32.4% developed some form of ROP, and all those ROP patients had the following characteristics at birth (median ± standard deviation scores): low weight (1098 ± 188 vs. 1393 ± 285 g), short length (36.74 ± 1.77 vs. 38.89 ± 3.08 cm), small cranial perimeter (26.03 ± 1.74 vs. 27.93 ± 1.81 cm) and young gestational age (29.7 ± 1.78 vs. 31.3 ± 1.79 weeks) (p < 0.05). Other factors previously associated with ROP that were also observed with statistically significant frequency in our ROP patients were bronchopulmonary dysplasia, intracranial haemorrhage, the need for erythrocyte transfusion or treatment with erythropoietin and sepsis (all p < 0.05). Levels of IGF1 at the 3rd week post‐partum, independent of gestational age at birth, were clearly lower in the group who developed ROP (29.13 vs. 43.16 ng/mL, p < 0.05). A value of 30 ng/mL of IGF1 in the third week post‐partum was found to have a 90% sensitivity in the diagnosis of ROP. A rapid rise in IGF1 levels between the 3rd and 5th weeks appeared to be related to the development of a higher stage of ROP. Conclusion: Determination of IGF1 serum levels in the 3rd week post‐partum, independent of gestational age at birth, provides a sufficient and reliable prognostic tool and allows the identification of a group of patients at high risk of developing the disease.  相似文献   
997.
Amplitude and phase of steady-state signals recorded in response to amplitude-modulated (AM) sine tones vary over time, suggesting that the steady-state response (SSR) reflects not only stimulus input but also its interaction with other input streams or internally generated signals. Alterations of the interaction between simultaneous SSRs associated with tinnitus were studied by recording the magnetic field evoked by AM-tones with one of three carrier and one of three modulation frequencies. Single AM-tones were presented in single presentation mode and superpositions of three AM-tones differing in carrier and modulation frequency in multiple presentation mode. Modulation frequency-specific SSR components were recovered by bandpass filtering. Compared with single mode, in multiple mode SSR amplitude was reduced in healthy controls, but increased in tinnitus patients. Thus, while in controls multiple response components seem to reciprocally inhibit one another, in tinnitus reciprocal facilitation seems to predominate. Reciprocal inhibition was unrelated to the phase coherence among SSR components, but was correlated with the frequency of phase slips, indicating that the lateral interaction among SSR components acts in a quasi-paroxysmal manner and manifests itself in terms of a random train of phase reset events. Phase slips were more frequent in patients than controls both in single and multiple mode. Together, these findings indicate that lateral or surround inhibition of single units in auditory cortex is reduced and suggest that in-field inhibition is increased in tinnitus.  相似文献   
998.
Aim: To test the hypothesis that implementing guidelines for the standardized care of the extremely premature infant (<27 weeks) in the first week of life would improve patient outcomes in an all referral NICU. Methods: Data were collected on all infants <27 weeks gestational age and <7 days of age on admission cared for using these small baby guidelines (SBG), as well as on all age‐matched infants admitted the year prior (comparison). Results: Thirty‐seven patients were cared for utilizing the SBG and 40 patients were in the comparison group. There were no differences between the groups in gestational age, birthweight or age on admission. There was no difference in survival to discharge (73% SBG, 70% comparison). The mean length of stay for survivors was 112 ± 38 days SBG and 145 ± 76 days (p < 0.05) comparison group. Survival without BPD was greater in the SBG group (24%) than in the comparison group (9%; p < 0.05), and survival without severe IVH was greater in the SBG group (65%) than in the comparison group (38%; p < 0.01). Conclusions: These data demonstrate that applying a unified approach to the care of the extremely premature infant in the first week of life resulted in a decrease in the length of hospitalization and improved patient outcomes.  相似文献   
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BACKGROUND: In response to growing demands on genetics departments and advances in genetic medicine, it has been proposed that primary care should provide a frontline service in clinical genetics. However, there are concerns that primary care may be unwilling or ill prepared to take on this new role. OBJECTIVES: This study aimed to review systematically the literature exploring the role of primary care in delivering genetic services, and define potential methods of supporting primary care in the provision of genetics services. METHODS: Seven electronic databases were searched. This was complemented by contacting experts in the field and handsearching reference lists. In total, 230 papers were identified, including traditional reviews, of which 96 were examined in detail. Fifty-one papers are included in this review. On account of the heterogeneity of papers identified, we conducted a qualitative synthesis of the results, focusing on five key questions. RESULTS: GPs accept that they have an increasing role to play in genetics, but lack confidence in their ability to do so because of limited knowledge of clinical genetics. Evidence from pilot studies of cystic fibrosis screening provides the strongest evidence for the feasibility of providing genetic services in primary care. CONCLUSIONS: Although genetic issues currently constitute a relatively small part of the overall workload in primary care, this will almost certainly change in the light of new genetic discoveries. Educational programmes and referral guidelines, computer decision support and genetic nurse specialist outreach clinics may provide useful methods of supporting GPs in the new field of primary care genetics.  相似文献   
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