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81.
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
82.
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
83.
84.
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
85.
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
86.
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
87.
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
88.
Plasma antipsychotic concentration and receptor occupancy, with special focus on risperidone long-acting injectable. 总被引:1,自引:0,他引:1
Although effective plasma concentration ranges have been established for some antipsychotics, conventional and atypical, there is considerable inter-patient pharmacokinetic variation. Positron-emission tomography (PET) can be used to estimate D(2)-like receptor occupancy in the brain needed for an antipsychotic effect and the level above which extrapyramidal side effects (EPS) develop. For conventional antipsychotics, the window occupancy is approximately 70-80%. For the atypical antipsychotic risperidone, the antipsychotic effect starts at approximately 60% occupancy, with occupancy above 80% leading to EPS. The new formulation, risperidone long-acting injectable (RLAI), comprises risperidone in a biodegradable polymer. It is effective long-term at doses of 25 or 50 mg injected i.m. every 2 weeks. The constant and slow release of the long-acting formulation leads to less fluctuation in plasma levels and to a D(2)-like receptor occupancy which is below the threshold for EPS. 相似文献
89.
Nicola Fiotti Franco Tubaro Nicola Altamura Gabriele Grassi Michèle Moretti Barbara Dapas Rossella Farra Michela Mizzau Gianfranco Guarnieri Stefano Buiatti Carlo Giansante 《Alcohol》2008,42(5):389-395
Alcoholic beverages are known to exert a protective effect on atherosclerotic disease. This study aimed to assess the in vivo and in vitro effects of alcohol on matrix metalloproteinase (MMP) -2 and -9, known to determine atherosclerosis progression. Eighteen healthy volunteers, regular drinkers (two standard alcohol servings/day, on average) at first examination (baseline) were asked to abstain from any alcoholic beverage for one week (abstention), and then to assume two standard alcohol servings of beer daily for 1 week (re-exposure). Activity of MMP-2 and -9, total antioxidant activity (AOA), glutathione (GSH) plasma levels were carried out at baseline, at the end of abstention, and after 1 week of re-exposure. To validate the in vivo results, MMP-2 activity and expression, AOA, and GSH, were determined in human smooth muscle cells treated for 96 h with increasing concentrations (12.5-100 mM) of ethanol. MMP-2, but not MMP-9 plasma activity was higher at abstention than at baseline or re-exposure (P<.001 and P< or =.005, respectively). Changes in AOA and GSH throughout the study were not significant. No correlation was found between MMPs and antioxidant activity. In vitro, ethanol at 25 mM reduced by around 10% MMP-2 activity (P=.003) in smooth muscle cells, whereas MMP-2 expression, AOA, and GSH were unaffected. Alcohol reduces MMP-2 plasma activity in healthy humans and in isolated vascular smooth muscle cells. This in vitro reduction is unrelated to MMP-2 expression in vascular cells or to antioxidant levels changes. 相似文献
90.
Salvatore Minisola Rossella Antonelli Addolorata Scarpiello Claudio Medori Carlo Valtorta Gianfranco Mazzuoli 《International Journal of Clinical & Laboratory Research》1984,14(4):649-655
Summary This study was carried out in order to investigate the effects of age on the urinary excretion of total and non-dialyzable
hydroxyproline (OHPr) in normal subjects. We found that total urinary OHPr was negatively correlated with age but, by means
of partial regression analysis, no correlation was found after correction for changes in creatinine clearance; on the contrary,
non-dialyzable OHPr showed a statistically significant negative correlation with age (r=−0.56) even when creatinine clearance
was held constant (p<0.05). A highly significant direct correlation was found between total and non-dialyzable OHPr in the
whole group (r=0.54) and when only premenopausal women and men under 60 years of age were considered (r=0.51). No correlation
was found when postmenopausal women and men more than 60 year-old were taken into account. Our data appear to indicate that
also the decrease in osteogenetic activity is responsible for the physiological late involutional bone loss; they also show
the importance of hormonal changes in inducing an uncoupling between bone formation and resorption.
This work was supported by a grant from theConsiglia Nazionale delle Ricerche (CNR), Roma, Italy 相似文献