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101.
Long-term clinical significance of frequent and complex ventricular tachyarrhythmias in trained athletes 总被引:5,自引:0,他引:5
Biffi A Pelliccia A Verdile L Fernando F Spataro A Caselli S Santini M Maron BJ 《Journal of the American College of Cardiology》2002,40(3):446-452
OBJECTIVES: The aim of this study was to clarify the clinical relevance of ventricular tachyarrhythmias assessed by 24-h ambulatory electrocardiograms (ECG) in a large, unique, and prospectively evaluated athletic population. BACKGROUND: For athletes with ventricular tachyarrhythmias, the risk of sudden cardiac death associated with participation in competitive sports is unresolved. METHODS; We assessed 355 competitive athletes with ventricular arrhythmias (VAs) on a 24-h ambulatory (Holter) ECG that was obtained because of either palpitations, the presence of > or = 3 premature ventricular depolarizations (PVDs) on resting 12-lead ECG, or both. RESULTS: Athletes were segregated into three groups: Group A with > or = 2,000 PVDs/24 h (n = 71); Group B with > or = 100 <2,000 PVDs/24 h (n = 153); and Group C with only <100 PVDs/24 h (n = 131). Cardiac abnormalities were detected in 26 of the 355 study subjects (7%) and were significantly more common in Group A (21/71, 30%) than in Group B (5/153, 3%) or Group C athletes (0/131, 0% p < 0.001). Only the 71 athletes in Group A were excluded from competition. During follow-up (mean, 8 years), 70 of 71 athletes in Group A and each of the 284 athletes in Groups B and C have survived without cardiovascular events. The remaining Group A athlete died suddenly of arrhythmogenic right ventricular cardiomyopathy while participating in a field hockey game against medical advice.Frequent and complex ventricular tachyarrhythmias are common in trained athletes and are usually unassociated with underlying cardiovascular abnormalities. Such VAs (when unassociated with cardiovascular abnormalities) do not convey adverse clinical significance, appear to be an expression of "athlete's heart syndrome," and probably do not per se justify a disqualification from competitive sports. 相似文献
102.
Genotype- and experience-dependent susceptibility to depressive-like responses in the forced-swimming test 总被引:4,自引:0,他引:4
Abstract
Rationale. The forced-swimming test (FST) is utilized to reproduce passive coping responses to stress that may model a relevant aspect
of human depression in rodent species. Animals showing high levels of passive responses to the FST are assumed to model pathologically
depressed individuals.
Objectives. We evaluated sensitivity of FST-induced behavioral responses to the interaction between genetic and environmental influences.
Methods. Behavioral responses to FST were evaluated in naive mice of the C57BL/6 and DBA/2 strains, in mice of both strains pre-exposed
to FST 14 days before test, and in FST-experienced animals subsequently exposed to 12 days of stress experience (food restriction).
Results. C57BL/6 mice are characterized by high propensity to adopt passive coping responses in the FST. Moreover, stress enhances
FST-induced immobility in mice of the C57BL/6 strain but reduces this response in DBA/2 mice. Finally, FST-induced immobility
in C57BL/6 mice is reduced by chronic treatment with clinically effective antidepressants.
Conclusions. These results support the view that behavioral and neural responses to FST exhibited by C57BL/6 mice can be usefully exploited
by pre-clinical research on depression.
Electronic Publication 相似文献
103.
Autorino GL Battisti A Deubel V Ferrari G Forletta R Giovannini A Lelli R Murri S Scicluna MT 《Emerging infectious diseases》2002,8(12):1372-1378
During the late summer of 1998, veterinary authorities in Tuscany, Italy, received reports of cases of neurologic disease among horses residing in a large wetland area located in the provinces of Florence and Pistoia. West Nile virus was isolated from two of the six horses that died or were euthanized. A retrospective epidemiologic study identified 14 clinical neurologic cases that occurred from August 20 to October 6 (attack rate of 2.8%). A serologic survey conducted over a 700-km2 area in stables with and without apparent clinical cases confirmed a wider spread of the infection, with an overall seroprevalence rate of 38% in the affected area. No significant differences in age-specific prevalence were observed, suggesting that the horses residing in the area had not been exposed previously to West Nile virus and supporting the hypothesis of its introduction in the wetland area during the first half of 1998. 相似文献
104.
105.
Minimally invasive video-assisted thyroidectomy for papillary carcinoma: a prospective study of its completeness 总被引:21,自引:0,他引:21
Miccoli P Elisei R Materazzi G Capezzone M Galleri D Pacini F Berti P Pinchera A 《Surgery》2002,132(6):1070-3; discussion 1073-4
BACKGROUND: The effectiveness of minimally invasive video-assisted thyroidectomy (MIVAT) in papillary thyroid carcinoma is still debated. Some are concerned about this procedure in patients with thyroid cancer. This prospective study aimed to demonstrate that near-total thyroidectomy can be performed by MIVAT with similar results compared with open thyroidectomy. METHODS: A total of 33 patients with a thyroid nodule proven to be a papillary thyroid carcinoma underwent a near-total thyroidectomy. They were randomly assigned to group A (n = 16) or group B (n = 17) who were treated either by MIVAT or conventional near-total thyroidectomy, respectively. Iodine-131 thyroid bed uptake and serum thyroglobulin were measured 1 month after operation. Data were analyzed by unpaired t test and Mann-Whitney statistic methods. RESULTS: . Mean iodine-131 uptake was 5.1 +/- 4.9% in group A and 4.6 +/- 6.7% in group B. Mean thyroglobulin serum levels were 5.3 +/- 5.8 ng/mL in group A and 7.6 +/- 21.7 ng/mL in group B. The differences were not statistically significant. CONCLUSIONS: The results of this study showed that the completeness obtained with MIVAT is similar to that obtained with open thyroidectomy, with the great advantage of a minimal neck wound. No conclusions can be drawn in terms of influence of MIVAT on the outcome of the patients with small papillary thyroid carcinoma. 相似文献
106.
Nappi RE Mancini M Veneroni F Colpi GM Ferdeghini F Polatti F 《Journal of sex & marital therapy》2002,28(Z1):187-193
The aim of the present study was to measure clitoral artery blood flow throughout the menstrual cycle and in oral contraceptive users. We recruited healthy young women (n = 19, age range: 21-28 years; body-mass index: 18-23 kg/m2) without sexual dysfunction (Female Sexual Functioning Index criteria; Rosen et al., 2000). Clitoral arterial peak systolic velocity (PSV) in at least two phases of the same ovulatory cycle or during the second week of the pill was measured by doppler ultrasonography. Clitoral arterial PSV measures (cm/s) were superimposable during the follicular and the luteal phase of the menstrual cycle (10.4 +/- 1.2 versus 10.2 +/- 1.6), whereas a slight but significant increase (12.2 +/- 1.2, f = 3.99; p < 0.04) was evident at the time of ovulation. In addition, PSV measures were significantly higher in women taking hormonal contraception compared to women studied throughout the menstrual cycle (14.2 +/- 2.7 versus 10.8 +/- 1.5; p < .001). Whether or not these preliminary data may be of any significance to female sexual arousal throughout the menstrual cycle remains to be established. 相似文献
107.
Synapses in the CA1 region of the hippocampus undergo bidirectional synaptic modification in response to different patterns of activity. Postsynaptic Ca2+ elevation can trigger either synaptic strengthening or weakening, depending on the properties of the local Ca2+ signal. During the pairing protocol for long-term potentiation (LTP) induction, the cell is depolarized under voltage-clamp and is given low-frequency synaptic stimulation. As an initial step toward understanding the Ca2+ dynamics during this process, we used confocal microscopy to study the Ca2+ signals in spines evoked by the depolarization itself. This depolarization activates voltage-dependent Ca2+ channels (VDCC), but whether these channels inactivate rapidly or remain functional throughout the long depolarizations used in the pairing protocol remains unknown. Cells were depolarized to 0 mV for 2-3 min. This depolarization led to a large initial elevation of Ca2+ in spines that never decayed back to resting levels. The maintained signal was close to the Kd of the low-affinity (5 microM) Ca2+ dye, Magnesium Green. We attempted to determine the functional role of this elevation, using the Ca2+-channel blocker D-890. The addition of D-890 in the internal solution produced a nearly complete abolition of the Ca2+ elevation during depolarization. Under these conditions, the NMDA conductance was normal, but LTP was almost completely blocked. This might suggest the importance of VDCC in LTP; however, we found that high concentrations of D-890 can directly inhibit calmodulin protein kinase II (CaMKII), an enzyme required for LTP induction. Thus, whereas D-890 is a useful tool for blocking postsynaptic VDCC, it cannot be used to study the contribution of these channels to plasticity. We conclude that the activation of VDCC produces a large and persistent elevation of Ca2+ in all spines, but does not produce either LTP or long-term depression (LTD) in the absence of synaptic stimulation. The possible reasons for this are discussed. 相似文献
108.
Etzl MM Kaplan AM Moss SD Spataro J Bonstelle CT Lawson MA Bandy DJ 《Journal of child neurology》2002,17(7):522-527
The pleomorphic xanthoastrocytoma is generally considered a low-grade neoplasm with favorable prognosis. These tumors, however, can demonstrate primary anaplastic features, undergo malignant transformation, disseminate, or progress with poor outcome. Currently, there are no histologic or clinical features that reliably predict recurrent tumor or tumor progression. We report three children with confirmed pleomorphic xanthoastrocytoma who were studied with positron emission tomography (PET) using [18F]fluorodeoxyglucose (FDG) coregistered with magnetic resonance imaging. One patient had decreased FDG metabolism and, despite a gross total resection and benign pathology, had early local recurrence. Subsequent to a second surgical resection and radiation therapy, he has remained stable for 8 years. One patient with significant FDG uptake had gross total resection of an anaplastic pleomorphic xanthoastrocytoma. Follow-up FDG studies showed no abnormal metabolic activity, and he has been stable without adjuvant treatment for 5 years. The last patient had intermediate FDG uptake and a moderate-grade pleomorphic xanthoastrocytoma by histopathology. She showed early tumor progression with spinal metastases. Following a near-total resection of the recurrent intracranial lesion and neuroaxis radiation, she has been stable for 4 years. Although there are still no reliable prognostic indicators for pleomorphic xanthoastrocytoma, PET with FDG correlates with histopathology, and increased uptake may be a marker for more malignant or aggressive tumors. The extent of surgical resection in regard to prognosis in our limited study is unclear but appears helpful in the anaplastic pleomorphic xanthoastrocytoma case. Adjuvant radiation therapy also may benefit certain patients. Further PET studies are warranted in this group of tumors. 相似文献
109.
Previous studies have found inconsistent relationships between restrained eating, dieting, and cortisol. The present study was designed to clarify the relationship between self-reported restrained eating and cortisol using multiple measures of dietary restraint. Eighty-five college-age women completed the Restraint Scale (RS) and the Cognitive Restraint Scale of the Three Factor Eating Questionnaire (TFEQ-R) and provided a saliva sample for analysis of cortisol. Both measures of restraint were positively associated with elevated levels of salivary cortisol, although the TFEQ-R was more strongly associated than the RS. Restrained eating, characterized by largely unsuccessful efforts to control eating, may lead to elevated cortisol levels. 相似文献
110.
Orlando L Curigliano G Colleoni M Fazio N Nole F Martinelli G Cinieri S Graffeo R Peruzzotti G Goldhirsch A 《Anticancer research》2002,22(5):3057-3059
Meningeal metastases occur in 2-3% of patients with breast cancer, leading to neurological morbidity and increased mortality. The criteria for treatment choice are controversial and intrathecal chemotherapy (ITC) has no documented role in the management of this disorder. We therefore evaluated the efficacy of an ITC regimen for patients presenting with carcinomatous meningitis from breast cancer. PATIENTS AND METHODS: Patients with meningeal carcinomatosis with or without concomitant parenchymal brain metastasis, were treated with repeated courses of intrathecal chemotherapy according to the following alternated weekly schedule: Day 1: Thiotepa 10 mg, methotrexate 15 mg, hydrocortisone 30 mg; Day 5: cytarabine (Ara-C) 70 mg, methotrexate 15 mg, hydrocortisone 30 mg. Folinic acid 15 mg was given orally, every six hours after methotrexate on days 2-3 and 6-7. RESULTS: Thirteen consecutive patients were treated. The median age was 45 (range 30-67) years. Eleven patients had performance status (PS) 2-3. Nine patients had other metastatic sites; synchronous parenchymal brain metastasis were present in 5 patients. Concomitant systemic chemotherapy was administered in 5 patients and external whole brain radiotherapy in 7 patients. With 12 evaluable patients we observed no responses or improvement in symptoms. Side-effects were minimal. CONCLUSION: In our series of patients, ITC failed to provide objective response or relief in clinical symptoms. Despite evidence reported in the literature indicating symptomatic improvement after ITC in a number of patients with leptomeningeal metastasis, the results of our study confirm the controversial role of ITC. New drugs and new modalities of treatment should be studied in order to efficiently control meningeal involvement of breast cancer. 相似文献