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Because of its role in osteoblastic metabolism, vitamin K has been studied with respect to bone. However, there has been limited research examining the influence of long-term vitamin K supplementation on bone mineral density (BMD). Therefore, the purpose of this study was to assess the impact of 6 months of vitamin K supplementation on BMD and biomarkers of bone in pre- and perimenopausal women. Based on previous work, we hypothesized that vitamin K would improve BMD and biochemical markers of bone formation. A double-blind, placebo-controlled, randomized trial is an effective way to study the impact of long-term supplementation. Thus, 14 pre- and perimenopausal women, 25 to 50 years of age, were randomly assigned to an experimental group (E) that received 600 μg/d of vitamin K in the form of phylloquinone (K1) or a control group (C) that received identical-looking placebo tablets. Regional BMD and percent body fat, measured by dual-energy x-ray absorptiometry, and serum osteocalcin and urinary N-telopeptide levels were all assessed at 0, 3, and 6 months. When BMD was measured across time, C had a significant increase (P = .011) in greater trochanter BMD compared to E. The E group had a nonsignificant increase (P = .067) in shaft BMD compared to the C group. There was no significant difference between E and C in serum osteocalcin concentrations over time. Urinary N-telopeptide levels increased significantly over time in E compared to C (P = .008). Six months of 600 μg/d vitamin K1 supplementation did not improve regional BMD in this group of pre- and perimenopausal women. 相似文献
83.
Movement disorder of premature infants with severe bronchopulmonary dysplasia: a new syndrome 总被引:6,自引:0,他引:6
A previously unrecognized, striking movement disorder has been observed in 10 premature infants with severe bronchopulmonary dysplasia. Chronic hypoxemia, hypercarbia, bronchospasm, and inadequate nutrition were present in all. The movement disorder developed from approximately the third postnatal month. The dominant movements involve the limbs, neck, trunk, and oral-buccal-lingual structures. The limb movements were most prominent distally and consisted of rapid, random, jerky movements (similar to chorea) and "restless" movements (similar to akathisia). Similar movements of the neck and face were observed; tongue movements had a "darting" quality. The oral-buccal-lingual movements were similar to the dyskinesia of older patients. Movements were exacerbated during episodes of respiratory failure and attenuated during sleep. All infants exhibited feeding disorders, largely due to tongue movements. In 3 infants treated with clonazepam, there was striking improvement in motor function, including feeding. The natural history was partial or complete resolution or a static course. Thus, of the 7 surviving infants, the movements were absent (without therapy) at 15, 18, and 30 months of age. In the remaining 4 infants (3 of whom receive clonazepam), the movements, though attenuated, persisted at 6, 12, 15 and 21 months of age, respectively. Neuropathologically, 1 infant showed neuronal loss with astrocytosis in caudate, putamen, globus pallidus, and thalamus. These data defined a previously unrecognized extrapyramidal movement disorder of infants with severe bronchopulmonary dysplasia; pathogenesis may be related to chronic hypoxemia. 相似文献
84.
Effect of oral contraceptives or dexamethasone on plasma beta-endorphin during the menstrual cycle 总被引:1,自引:0,他引:1
G Comitini F Petraglia F Facchinetti M Monaco A Volpe A R Genazzani 《Fertility and sterility》1989,51(1):46-50
Several studies have showed a significant increase of plasma beta-endorphin levels during the periovulatory days of the menstrual cycle. The aim of the present study was to investigate the origin of the periovulatory changes of plasma beta-endorphin, trying to discriminate between a possible ovarian and/or pituitary origin. Daily plasma beta-endorphin, luteinizing hormone (LH), and cortisol levels were measured from the 8th to the 20th day of the menstrual cycle in healthy normal-cycling women (10 cases) before and during dexamethasone (DEX; 6 cases) or estroprogestinic treatment with monophasic (5 cases) or triphasic (5 cases) pill. In the control menstrual cycle, during the preovulatory days, a significant increase of plasma beta-endorphin was found. While oral contraceptives abolished the midcycle increase of plasma beta-endorphin, the periovulatory plasma beta-endorphin peak was present during DEX treatment. Plasma cortisol levels did not show any significant change throughout the control menstrual cycle, while they were significantly lowered by the DEX administration and significantly increased during estroprogestinic treatment. These results suggest that the increase of plasma beta-endorphin during the periovulatory days is related to the ovulatory function, and suggest a possible ovarian origin. 相似文献
85.
G. Frasci G. Comella P. Comella F. Salzano L. Cremone N. Della Volpe A. Imbriani G. Persico 《Breast cancer research and treatment》1995,35(2):147-156
Summary Mitoxantrone (MTZ) and vinorelbine (VNR) have shown a good efficacy in advanced breast cancer. We conducted a phase I-II trial to determine the MTDs and best schedule of these drugs, in advanced breast cancer patients, when granulocyte-colony stimulating factor (G-CSF) support was given. The starting dose-intensity level was MTZ 3 mg/m2/week + VNR 15 mg/m2/week; dose was escalated at each step by 1 mg/m2/week for MTZ and 5 mg/m2/week for VNR, until dose limiting toxicity (DLT) developed in 33% or more of the patients at the first course. G-CSF 5 µg/kg/day d 3–13 was administered at each cycle from dose level 2 on. For each dose step we planned 3 different schedules (a = total dose of MTZ on day 1; b = total dose d 1 and 8; c = weekly schedule). At the time of this analysis (December 1993) 43 patients with locoregionally advanced or metastatic breast cancer have entered this study, 23 of whom had received prior chemotherapy other than adjuvant. Toxicity has been primarily hematologic. Non hematologic toxicity never caused interruption of dose escalation.Overall 8 patients developed DLT at the first course. Dose escalation was stopped at level 3 in patients receiving schedules a or b, and in those receiving schedule c the dose was escalated until level 5. The MTD was MTZ 6 mg/m2 and VNR 30 mg/m2 weekly. Age, dose level, and PS were found to be correlated with neutrophil and platelet nadirs, but dose level was the only independent variable predictive of myelotoxicity at multiple regression analysis.Forty-one patients were evaluable for response. Five complete and 16 partial responses were recorded for a 51% [35–67] overall response rate. This was 67% (12/18) in chemotherapy naive patients as compared to 39% (9/23) in those who had been pretreated.Seven of 21 (33%) patients receiving dose level 1 and 2 responded as compared to 14/20 (70%) patients who received higher dose-intensity (p = 0.02). Dose level and pretreatment were the only variables significantly associated with response rate at multiple logistic analysis.The median TTP was 9.5 months for the entire group. It was significantly better in patients who received a dose level > 2 (15 vs. 7; p = 0.015). However, the chemotherapy dose level did not significantly predict outcome after correction for pretreatment (yes vs. no), at multivariate Cox analysis.In conclusion, G-CSF support allows us to achieve a high dose-intensity of MTZ and VNR. Weekly administration of mitoxantrone is recommended to achieve the maximum dose level.Dose escalation seems to provide a significant gain in terms of response rate, although the low number of patients enrolled and the short follow-up prevents us from drawing any conclusion on its effects on TTP and survival. Further controlled trials of this combination in unpretreated patients with advanced breast cancer are needed to determine whether dose escalation can really improve prognosis. 相似文献
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88.
Della Volpe A D'Agostino GW Varricchio AM Mansi N 《International journal of immunopathology and pharmacology》2002,15(1):35-40
The aim of this study was to demonstrate the efficacy and safety of the sublingual-swallow allergen-specific immunotherapy (SLIT) in a paediatric population suffering from allergic rhinitis and related pathologies. From March 1994 through March 2000, at our ENT Department 4000 children (1800 male and 2200 female), aged 3 to14 years, were examined for recurrent nasal obstruction and nasal polyps. 2400 (60%) of them were allergic and underwent the following investigations: Impedance test, Pure tone audiometry, rhinomanometry, Prick test, RAST, nasal provocation test and paranasal sinus TC without contrast media. Of the allergic group we admitted 288 patients(12%) to a 3 yr SLIT, meeting the following criteria: children aged 5 years or more, mono-sensitised to one allergen and with family cooperation support. After three years of SLIT, we observed complete symptom remission and a marked improvement in instrumental examinations in 80% of these children. The improvement was poor in 8% of patients, while in 12% of the subjects no changes in symptoms and instrumental results were detected. These results are in agreement with previously published studies and confirm that SLIT can be a valid tool for treating allergic upper respiratory tract diseases in children. 相似文献
89.
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