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51.
Morphological analysis of degeneration and regeneration of syncytiotrophoblast in first trimester placental villi during organ culture 总被引:3,自引:1,他引:3
We have recently shown using dansyl-L-lysine exclusion studies that the
release of human chorionic gonadotrophin (HCG) in conjunction with L-
lactate dehydrogenase (LDH) from first trimester villi during organ culture
is symptomatic of syncytiotrophoblast degeneration. The purpose of this
study was to examine chorionic villi at the ultrastructural level in order
to determine events occurring during organ culture. The tissue was sampled
after 0, 24, 48 and 120 h in culture and processed for electron microscopy.
In addition to confirming the previously recorded syncytial degeneration,
the electron micrographs showed clearly the generation of a new
syncytiotrophoblast layer. The new layer, derived from differentiating
cytotrophoblast cells, was largely formed by 48 h and was maintained for at
least 120 h in culture. This study demonstrates a model which provides an
opportunity to study the differentiation of cytotrophoblast cells whilst
they retain their anatomical relationships within the villous structure.
相似文献
52.
Roos Nuboer Gerard JJM Borsboom Jan Age Zoethout Hans M Koot Jan Bruining 《Pediatric diabetes》2008,9(4PT1):291-296
Objective: Effects of pump treatment vs. four times daily injections were explored in children with diabetes with regard to quality of life and impact of disease as well as adverse effects and parameters of metabolic control.
Methods: An open, parallel, randomized controlled prospective comparative study lasting 14 months was completed by 38 type 1 children with diabetes (age 4–16 yr) following a 3.5-months run-in phase. Standardized quality-of-life Pediatric Quality of life Inventory (PedsQL) and impact of disease scores were obtained every 3.5 months as well as regular medical parameters. Parallel treatment group data and longitudinal within-patient data were analysed for each treatment modality.
Results: Within-patient comparisons of the two treatment modalities showed significant improvement in PedsQL and impact scores after pump treatment. Treatment group comparisons did not show significant improvement. Pump treatment resulted in decreased symptomatic hypoglycaemia and lowered haemoglobin A1c by 0.22% after run in.
Conclusions: Within-patient comparison suggests that metabolic control, frequency of severe hypoglycaemia (a threefold decrease), quality of life and impact of disease scores are improved by pump treatment in comparison to regular treatment with four daily insulin injections. 相似文献
Methods: An open, parallel, randomized controlled prospective comparative study lasting 14 months was completed by 38 type 1 children with diabetes (age 4–16 yr) following a 3.5-months run-in phase. Standardized quality-of-life Pediatric Quality of life Inventory (PedsQL) and impact of disease scores were obtained every 3.5 months as well as regular medical parameters. Parallel treatment group data and longitudinal within-patient data were analysed for each treatment modality.
Results: Within-patient comparisons of the two treatment modalities showed significant improvement in PedsQL and impact scores after pump treatment. Treatment group comparisons did not show significant improvement. Pump treatment resulted in decreased symptomatic hypoglycaemia and lowered haemoglobin A1c by 0.22% after run in.
Conclusions: Within-patient comparison suggests that metabolic control, frequency of severe hypoglycaemia (a threefold decrease), quality of life and impact of disease scores are improved by pump treatment in comparison to regular treatment with four daily insulin injections. 相似文献
53.
Transient synovitis of the hip in children: role of US 总被引:7,自引:0,他引:7
Marchal GJ; Van Holsbeeck MT; Raes M; Favril AA; Verbeken EE; Casteels- Vandaele M; Baert AL; Lauweryns JM 《Radiology》1987,162(3):825-828
Transient synovitis of the hip remains a common diagnostic problem for the clinician. The physical signs are not pathognomonic of the condition, and the classic technical examinations are of little help. Therefore, the authors retrospectively studied the value of hip arthrosonography in 46 children with clinical symptoms suggesting pathologic hip conditions. In 20 of the 21 patients with a final diagnosis of transient synovitis, articular effusion was detected on ultrasound (US). Conventional radiography showed an increased medial joint space in only eight of these patients. Increased echogenicity of the articular fluid was found in both transient synovitis and septic arthritis. The high sensitivity of US in detecting intraarticular fluid was demonstrated by cadaver studies. 相似文献
54.
55.
Comparison of one-lung ventilation and high-frequency ventilation in thoracoscopic surgery. 总被引:1,自引:0,他引:1
OBJECTIVE: To report our experience of the use of high frequency ventilation (HFV) in thoracoscopic surgery. DESIGN: Retrospective study. SETTING: University Hospital Rotterdam, The Netherlands. SUBJECTS: 31 patients (18 men and 13 women, mean age 42 years, range 26-67 years) who underwent 46 thoracoscopic procedures between January 1992 and December 1997. INTERVENTIONS: Until October 1994 patients had conventional mechanical ventilation with a double-lumen tube. Since then HFV has been used. MAIN OUTCOME MEASURES: Duration of induction, oxygen saturation, and end-tidal carbon dioxide tension. RESULTS: 25 procedures were done with a double-lumen endotracheal tube for one-lung ventilation and in 21 HFV was used. Induction of anaesthesia took significantly less time in the HFV group (median 14 minutes) compared with one-lung ventilation group (median 31 minutes) (p < 0.05). There were no significant differences between the groups in either SaO2 or end-tidal CO2. CONCLUSION: HFV is both safe and simple for use in thoracoscopic surgery. 相似文献
56.
57.
S L C E Buijk I C Gyssens J W Mouton A Van Vliet H A Verbrugh H A Bruining 《The Journal of antimicrobial chemotherapy》2002,49(1):121-128
Ceftazidime demonstrates time-dependent killing, which is maximal at 4 x or 5 x MIC for the organism, consequently continuous infusion (CI) has been proposed to ensure adequate ceftazidime concentrations for the entire course of therapy. Severe intra-abdominal infections (IAIs) require surgical or percutaneous drainage for management, and ceftazidime is frequently prescribed. Cardiovascular or metabolic changes and renal or liver dysfunction may alter drug pharmacokinetics during severe IAIs, and no data exist on concentrations of ceftazidime reached in the peritoneal fluid. The objectives here were to determine the pharmacokinetics of ceftazidime during continuous and intermittent administration in patients with severe IAIs, and to measure the concentrations of ceftazidime in the peritoneal exudate. Eighteen surgical patients with severe IAI and a creatinine clearance of >30 mL/min were studied. A non-randomized pilot study of six patients treated with CI alone was followed by a prospective, randomized comparative study of 12 patients. Pilot study patients received ceftazidime 1 g iv followed by a 4.5 g CI over 24 h. Randomized patients received either ceftazidime continuously as above or 1.5 g tds. Samples for pharmacokinetic analyses were collected on days 2 and 4. Ceftazidime concentrations were determined by high-performance liquid chromatography. CI resulted in a mean serum concentration >40 mg/L and a T> 4 x MIC for most pathogens encountered in severe IAIs for >90% of the course of therapy in both serum and peritoneal exudate. Eight-hourly administration resulted in T> 4 x MIC for most pathogens encountered in severe IAIs for >90% of the dosing interval, but in peritoneal exudate for only 44% of the dosing interval. During CI, AUCs in the peritoneal exudate were c. 60% of the concomitant serum AUCs. In critically ill surgical patients with severe IAIs, CI of ceftazidime resulted in more favourable concentrations in serum and peritoneal exudate than 8-hourly bolus infusion. 相似文献
58.
Reinhart K Glück T Ligtenberg J Tschaikowsky K Bruining A Bakker J Opal S Moldawer LL Axtelle T Turner T Souza S Pribble J 《Critical care medicine》2004,32(5):1100-1108
OBJECTIVE: Binding of bacterial cell wall components to CD14 and co-receptors on myeloid cells results in cellular activation and production of proinflammatory mediators. A recombinant anti-CD14 monoclonal antibody (IC14) has been shown to decrease lipopolysaccharide-induced responses in animal and human models of endotoxemia. This study was performed to evaluate the safety, pharmacokinetics, pharmacodynamics, and clinical pharmacology of IC14 in patients with severe sepsis. DESIGN: Randomized, double-blind, placebo-controlled, dose-ranging, multiple-center trial. SETTING: Six medical and surgical intensive care units located in Germany and The Netherlands. PATIENTS: Forty patients with severe sepsis. INTERVENTIONS: IC14 was administered intravenously to eight patients/cohort as single (1 mg/kg or 4 mg/kg) or multiple doses (4 mg/kg daily for 4 days, or 4 mg/kg on day 1 followed by 2 mg/kg daily for 3 days). A placebo group (two patients/cohort) was also included. MEASUREMENTS AND MAIN RESULTS: The overall incidence and types of adverse events were similar among treatment groups. One patient in the group receiving multiple-dose IC14 4 mg/kg daily for 4 days experienced an anaphylactic reaction after receiving the first dose of study drug. IC14 did not induce antibody formation or increase the incidence of secondary bacterial infection. A mean IC14 serum concentration of approximately 1 microg/mL was required to achieve 50% of maximum membrane-bound CD14 receptor occupancy on peripheral blood monocytes. The pattern of proinflammatory and anti-inflammatory cytokines, chemokine, soluble receptor, soluble E-selectin, and acute phase proteins in response to treatment was highly variable by patient and IC14 treatment group. CONCLUSIONS: Single and multiple doses of IC14 were generally well tolerated and did not induce antibody formation or increase the incidence of secondary bacterial infection. The results suggest that CD14 blockade with IC14 warrants further clinical investigation to determine its ability to attenuate the proinflammatory response due to infection. 相似文献
59.
GJ Levy ; G Selset ; D McQuiston ; SJ Nance ; G Garratty ; LE Smith ; D Goldfinger 《Transfusion》1988,28(3):265-267
Several published reports have documented the variable survival of Yt(a+) red cells (RBC) in patients with anti-Yt(a) as measured by 51Chromium (Cr)-labeled RBC survival studies. Similar studies with anti-Yt(b) have not been reported. A 51Cr-labeled RBC survival study was performed using Yt(b+) RBCs and a monocyte monolayer assay in a young hemodialysis patient who required chronic transfusion therapy and who had developed anti-Yt(b). The survival of the transfused RBCs was 100 and 93 percent at 1 and 24 hours, respectively, with a half life of 21 days at termination of the study (normal, 28 to 32 days). These results showed no evidence of rapid destruction of the Yt(b+) RBCs, indicating that this patient could be transfused safely with blood from Yt(b+) donors. Long-term survival of the 51Cr-labeled Yt(b+) RBCs was shortened moderately, however, a finding that correlated with a slightly abnormal monocyte monolayer assay test. 相似文献
60.
两种麻醉方法对单双肺通气期间能量代谢和呼吸氧价及应激反应的影响 总被引:1,自引:0,他引:1
目的:观察胸段硬膜外复合全静脉麻醉和全静脉麻醉对单、双肺通气能量代谢、呼吸氧价和应激反应的影响,比较两者的差异。方法:选择2004-07/2005-01徐州医学院附属医院心胸外科择期行食管癌根治术且需要单肺通气的患者40例,按随机数字表法分为硬膜外复合全静脉麻醉组(n=20)和全静脉麻醉组(n=20),经患者同意并签字后进入试验。分别在单肺通气和双肺通气时进行氧耗量、二氧化碳排出量、能量代谢和呼吸商测定,同时测量肾上腺素、去甲肾上腺素、皮质醇和血糖水平。结果:40例患者全部进入结果分析,无脱落。①在单、双肺通气时硬膜外复合全静脉麻醉组的氧耗量、二氧化碳排出量、能量代谢均高于全静脉麻醉组(P<0.05);两组患者单肺通气时段氧耗量、二氧化碳排出量、能量代谢低于双肺通气时段,但差异无显著性意义(P>0.05)。②在单、双肺通气时硬膜外复合全静脉麻醉组的肾上腺素、去甲肾上腺素、皮质醇和血糖水平均低于全静脉麻醉组(P<0.05);单、双肺通气相比,两组患者肾上腺素、去甲肾上腺素变化差异无显著性意义(P>0.05)。结论:与全静脉麻醉相比,胸段硬膜外阻滞复合全静脉麻醉能够增加胸科手术的氧耗量、能量代谢,减轻应激反应。单、双肺通气期间没有明显差异。 相似文献