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71.
A randomized study was designed to evaluate the effects of two different dexamethasone courses on the growth of preterm infants. The first phase included 30 preterm infants at high risk for chronic lung disease (CLD). 15 babies (moderately early dexamethasone group) were treated with dexamethasone for 14 days, from the 10th day of life, and received a total dose of 4.75 mg/kg; 15 babies were assigned to the control group. The second phase included 30 preterm infants at high risk for CLD. 15 babies (early dexamethasone group) were treated with dexamethasone for 7 days, from the 4th day of life, and received a total dose of 2.38 mg/kg; 15 babies were assigned to the control group. All the main clinical baseline characteristics were similar between the groups both in the first and in the second phase. Infants given the two dexamethasone courses showed significantly reduced weight gain during the period of treatment when compared to the respective control group, but they had a weight catch-up soon after the end of treatment. At 30 days of life the weight and length gain of each treated group were similar to those of control infants, but the moderately early dexamethasone group showed a significantly poorer head growth. No differences between the groups were observed at discharge. Dexamethasone treatment induces a slower weight gain which is time-limited to the period of treatment and is followed by a body weight catch-up. However, the poorer head growth detected at 30 days of life in the infants who received a higher dose of dexamethasone could indicate important adverse effects, possibly dose-related, on postnatal brain growth and development.  相似文献   
72.
The larynges of 8 healthy and informed volunteers were studied with a superconductive MR unit at 1.5 T together with those of 10 patients with extralaryngeal pathologic conditions. The study was performed with round surface coils (5") and with dedicated sellar coils in the anterior neck. Slices were 5 mm thick, and acquired on the coronal, axial, and sagittal planes, with T1-weighting; axial scans were repeated in the same locations with double echoes, with proton-density and T2-weighting. Five patients underwent additional scans after Gd-DTPA. The larynx of a semi-frozen cadaver was examined with sellar surface coils, on similar scanning planes and with similar pulse sequences to those described above; the larynx was removed, investigated with mammographic technique, and subsequently analyzed with thin CT slices and a high-resolution reconstruction algorithm for the study of laryngeal cartilage. Axial anatomical sections were then compared with MR and CT scans, and the anatomical structures were recognized on the triplanar MR scans of a volunteer's larynx. Besides MR anatomy of supporting laryngeal structures, the authors describe in detail the muscles, plicae, spaces and cavities which can be identified on the various planes, together with the changes in signal after Gd-DTPA.  相似文献   
73.
Cardiac complications are the main cause of perioperative mortality. A preoperative electrocardiogram and cardiologist's consultation are usually performed to get information about cardiac state of patients undergoing surgery and to prevent complications. In their study the Authors applied to 1715 patients undergoing surgery an evaluation schedule for the cardiac surgical risk, including an ECG as first-level test, performed systematically on the whole sample. The aim was to assess predictive value of this preoperative examination to verify its efficacy as routine test. Basing on results achieved, electrocardiogram is not routinely indicated before noncardiac elective surgery, but it should be requested for the patients having high risk of cardiac complications at an accurate clinical-anamnestic examination. Therefore, clinical judgement, that is the first level of any preoperative evaluation, should be the basis for ordering an ECG to be considered a second-level test.  相似文献   
74.
OBJECTIVE: To investigate the effect of different delivery room strategies on survival, short term morbidity, and outcomes in extremely premature infants. METHODS: This retrospective cohort study included all preterm infants with a gestational age between 24 and 28 weeks who were born in 1992-1997 (period A; n = 161) and in 1998-2003 (period B; n = 163). In period A, elective intubation was performed. In period B, if spontaneous breathing was present, nasal continuous positive airway pressure (nCPAP) was applied. RESULTS: Survival rate and the number of never-intubated infants significantly increased in period B. No differences were found concerning short-term morbidity. Among major outcomes, the need for retinopathy of prematurity (ROP) surgery and the length of stay were significantly lower in period B. Subgroup analysis showed no significant differences from period A to period B in infants with gestational age 24-26 weeks. In the 27-28 weeks subgroup, the never-intubated infants rate increased from 2.8% to 21.3% and survival rate increased from 63% to 79%. A reduced need for ROP surgery and a shorter hospital stay were also observed. CONCLUSIONS: Changes in delivery room strategy tending to reduce mechanical ventilation in extremely premature infants are likely to benefit essentially infants of 27-28 weeks of gestation. Extension of such benefits to premature infants at the limit of viability requires further research.  相似文献   
75.
PURPOSE: Point mutations within the ABL kinase domain of the BCR-ABL gene have been associated with clinical resistance to imatinib mesylate in chronic myeloid leukemia (CML) patients. To shed further light on the frequency, distribution, and prognostic significance of ABL mutations, we retrospectively analyzed a homogeneous cohort of late chronic phase CML patients who showed primary cytogenetic resistance to imatinib. PATIENTS AND METHODS: Using denaturing high-performance liquid chromatography (D-HPLC) and sequencing, we screened for ABL mutations in a total of 178 bone marrow and/or peripheral blood samples from 40 late chronic phase CML patients homogeneously treated with imatinib 400 mg/d, who did not reach a major cytogenetic response at 12 months. RESULTS: Mutations were found in 19 of 40 patients (48%). Mutations were already detectable by D-HPLC at a median of 3 months from the onset of therapy. The presence of a missense mutation was significantly associated with a greater likelihood of subsequent progression to accelerated phase/blast crisis (P = .0002) and shorter survival (P = .001). Patients carrying mutations falling within the P-loop seemed to have a particularly poor outcome in terms of time to progression (P = .032) and survival (P = .045). CONCLUSION: Our results show that, irrespective of the hematologic response, monitoring for emerging mutations in the first months of therapy may play a role in detecting patients with worse prognosis, for whom a revision of the therapeutic strategy should be considered.  相似文献   
76.
Macrolides are widely used antibacterial agents. Although generally well tolerated, they have a number of important additional pharmacological effects, which can sometimes result in significant adverse reactions. This review focuses on three of these side effects: the prokinetic action associated with stimulation of motilin receptors, the proarrhythmic effect due to prolongation of the QT interval of the electrocardiogram and the potential for drug interactions due to inhibition of drug metabolising enzymes. For macrolides that have obtained marketing authorisation in Italy, United Kingdom or United States of America, we also considered whether these actions are properly reported in the approved summaries of the product characteristics and tried to provide strategies to identify patients at risk of significant side effects when macrolides are administered.  相似文献   
77.
Adjuvant chemotherapy and endocrine therapy can induce early iatrogenic menopause or worsen pre-existing menopausal symptoms in breast cancer survivors (BCS). The second most frequent menopausal symptom after hot flushes is the genitourinary syndrome (GSM). Since hormone replacement therapy is contraindicated in BCS, vaginal laser might represent a new nonhormonal option for GSM. This study aims at evaluating the effectiveness of the fractional CO₂ vaginal laser for GSM in BCS compared with healthy women. This is a retrospective study on 135 postmenopausal women (45 BCS and 90 healthy women) who underwent fractional CO2 laser for GSM. Objective (VHI and VVHI) and subjective outcomes (VAS for dyspareunia and vaginal dryness and a pain questionnaire) were evaluated at baseline visit and at every follow-up visit. Subjective and objective parameters improved significantly in both groups after laser therapy. The improvement was progressive and long-lasting up to 12 months after the end of the treatment. No severe adverse events were observed during the treatment. Fractional CO₂ vaginal laser induces a significant and long-lasting improvement on GSM symptoms in BCS. However, this improvement is slower than in healthy women undergoing the same treatment. Laser therapy turns out to be safe and well-tolerated.  相似文献   
78.
Besides its well-established oncosuppressor activity, a key function of p53 in regulating metabolic pathways has been recently identified. Nevertheless, the role of p53 with respect to diabetes mellitus (DM) appears highly controversial. To address this issue, we have used the cis-imidazoline compound Nutlin-3, an inhibitor of MDM2/p53 interaction, which represents a potent and selective non-genotoxic activator of the p53 pathway both in in vivo and in vitro experimental settings. Experimental DM was induced by intraperitoneal injections of low concentrations of streptozotocin (STZ) in C57BL/6N mice (n = 20). A group of control vehicle-injected mice (n = 10) and of STZ-treated mice (n = 10) was co-injected with Nutlin-3. Mice co-injected with STZ + Nutlin-3 exhibited attenuated features of DM with respect to animals treated with STZ alone. Indeed, STZ + Nutlin-3-treated mice were characterized by significantly (p < 0.05) lower levels of hyperglycemia, reduced weight loss, and increased spleen weight. In addition, STZ alone promoted a marked decrease in the levels of several circulating cytokines, including interleukin-12 (IL-12)p40. On the other hand, co-injection of STZ + Nutlin-3 significantly (p < 0.01) counteracted IL-12p40 down-modulation. In vitro experiments performed on the RAW264.7 macrophagic cell line model, used as cellular source of IL-12p40, demonstrated that Nutlin-3 treatment increased IL-12p40 release, strongly suggesting a direct effect of Nutlin-3 on the immune system. Overall, these data demonstrate that systemic administration of Nutlin-3 ameliorates the severity of STZ-induced DM and increases the levels of circulating IL-12p40.  相似文献   
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