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11.
Gerard M Ribbers Theo Mulder Alexander C Geurts Rob A den Otter 《Archives of physical medicine and rehabilitation》2002,83(1):81-85
OBJECTIVE: To test whether central motor processing can be impaired in chronic reflex sympathetic dystrophy (RSD). DESIGN: Experimental 2-group analysis. SETTING: Tertiary care center in the Netherlands. PARTICIPANTS: Five patients with stage 3 RSD of the left forearm, free of symptoms and complaints in the right forearm; and 10 healthy control subjects. INTERVENTION: On a digitizer, RSD patients and controls had to draw 3 sequences of graphemes of different complexity with their (unaffected) dominant right hand. The drawing tracks were segmented in time periods between points of velocity minima of the pen tip. MAIN OUTCOME MEASURES: Mean velocity, coefficients of variation of both length and movement time per segment, and mean intersegmental pausing time were calculated for each sequence. RESULTS: A repeated-measures analysis of variance by using the multivariate method yielded a 35% lower mean velocity (F(1,13) = 5.83, P =.031), a 110% larger segment length variability (F(1,13) = 9.72, P =.008) and a 60% larger variability of movement time per segment (F(1,13) = 5.78, P =.032) in RSD patients. No group difference was found for intersegmental pausing time or any interaction effect with the type of task. CONCLUSION: Patients with chronic RSD have a normal ability to preprogram sequential movements of their unaffected hand; but with impaired temporospatial coding and movement execution. We concluded that cortical mechanisms may be involved in motor impairments in patients with chronic RSD. 相似文献
12.
Effect of compressive follower preload on the flexion-extension response of the human lumbar spine. 总被引:5,自引:0,他引:5
Avinash G Patwardhan Robert M Havey Gerard Carandang James Simonds Leonard I Voronov Alexander J Ghanayem Kevin P Meade Thomas M Gavin Odysseas Paxinos 《Journal of orthopaedic research》2003,21(3):540-546
Traditional experimental methods are unable to study the kinematics of whole lumbar spine specimens under physiologic compressive preloads because the spine without active musculature buckles under just 120 N of vertical load. However, the lumbar spine can support a compressive load of physiologic magnitude (up to 1200 N) without collapsing if the load is applied along a follower load path. This study tested the hypothesis that the load-displacement response of the lumbar spine in flexion-extension is affected by the magnitude of the follower preload and the follower preload path. Twenty-one fresh human cadaveric lumbar spines were tested in flexion-extension under increasing compressive follower preload applied along two distinctly different optimized preload paths. The first (neutral) preload path was considered optimum if the specimen underwent the least angular change in its lordosis when the full range of preload (0-1200 N) was applied in its neutral posture. The second (flexed) preload path was optimized for an intermediate specimen posture between neutral and full flexion. A twofold increase in flexion stiffness occurred around the neutral posture as the preload was increased from 0 to 1200 N. The preload magnitude (400 N and larger) significantly affected the range of motion (ROM), with a 25% decrease at 1200 N preload applied along the neutral path. When the preload was applied along a path optimized for an intermediate forward-flexed posture, only a 15% decrease in ROM occurred at 1200 N. The results demonstrate that whole lumbar spine specimens can be subjected to compressive follower preloads of in vivo magnitudes while allowing physiologic mobility under flexion-extension moments. The optimized follower preload provides a method to simulate the resultant vector of the muscles that allow the spine to support physiologic compressive loads induced during flexion-extension activities. 相似文献
13.
High-protein Weight-loss Diets: Are They Safe and Do They Work? A Review of the Experimental and Epidemiologic Data 总被引:6,自引:0,他引:6
Julie Eisenstein M.D. Susan B. Roberts Ph.D. Gerard Dallal Ph.D. Edward Saltzman M.D. 《Nutrition reviews》2002,60(7):189-200
Recommendations for increased consumption of protein are among the most common approaches of popular or fad diets. This review summarizes the effects of dietary protein on satiety, energy intake, thermogenesis, and weight loss, as well as its effect on a variety of health outcomes in adults. In short-term studies, dietary protein modulates energy intake via the sensation of satiety and increases total energy expenditure by increasing the thermic effect of feeding. Whereas these effects did not contribute to weight and fat loss in those studies in which energy intake was fixed, one ad libitum study does suggest that a high-protein diet results in a greater decrease in energy intake, and therefore greater weight and fat loss. In terms of safety, there is little long-term information on the health effects of high-protein diets. From the available data, however, it is evident that the consumption of protein greater than two to three times the U.S. Recommended Daily Allowance contributes to urinary calcium loss and may, in the long term, predispose to bone loss. Caution with these diets is recommended in those individuals who may be predisposed to nephrolithiasis or kidney disease, and particularly in those with diabetes mellitus. 相似文献
14.
Pre-excitation disorders have an estimated prevalence of 0.15 per cent. Advances in electrophysiological mapping and the increasing sophistication of surgical techniques have resulted in an increasing role for definitive surgical treatment. A retrospective chart review of 181 patients undergoing 197 procedures for surgical ablation of accessory atrioventricular pathways between June 1981 to June 1986 was performed. Mean age of the patients was 30 years (range 6-66) with a preponderance of males (59 per cent). Associated cardiac disease was found in 18 (9.9 per cent) patients. Induction of anaesthesia employed either a barbiturate-relaxant (83 per cent) or a narcotic-benzodiazepine-relaxant (17 per cent) and was uneventful in all cases. In 14 per cent of cases a pure narcotic relaxant technique was employed for maintenance of anaesthesia, whereas a balanced technique with isoflurane (29 per cent), enflurane (34 per cent), or halothane (22 per cent) was utilized for the remainder. Muscle relaxation was provided by d-tubocurarine in 35 (18 per cent) procedures and pancuronium in the remaining 162 (82 per cent) procedures. There was no significant correlation between intraoperative arrhythmias and type of anaesthetic used. Although recognizing the potential for malignant arrhythmias, our experience (within the confines of a retrospective analysis) suggests that the majority of these patients can be managed successfully using standard anaesthetic techniques. 相似文献
15.
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17.
Stomach rupture can occur as a consequence of the expansion of compressed air during rapid ascent after diving. We present
the case of a middle-aged woman who suffered a gastric tear from surfacing too quickly after diving, and discuss the diagnosis
and management of such patients by reviewing previously reported similar events. Gastric barotrauma should be suspected in
divers who complain of abdominal pain, even in the absence of frank signs of peritoneal irritation. Although pneumoperitoneum
is always present in these patients, it can also occur as a consequence of pulmonary barotrauma, making gastroscopy or radiological
contrast studies, or both, essential for a definitive diagnosis. Surgical repair represents the treatment of choice for an
active full-thickness tear and, if associated with arterial gas embolism or decompression sickness, should ideally be performed
in a center where a category I (intensive care-capable) hyperbaric unit is available.
Received: March 18, 2002 / Accepted: September 3, 2002
Reprint requests to: L.V. Titu 相似文献
18.
David M Spiegel Beverly Farmer Gerard Smits Michel Chonchol 《Journal of renal nutrition》2007,17(6):416-422
OBJECTIVE: This study was designed to evaluate the efficacy of magnesium carbonate as a phosphate binder in hemodialysis patients. DESIGN: This study was a prospective, randomized, open-label trial comparing magnesium carbonate/calcium carbonate versus calcium acetate as a sole phosphate binder. SETTING: This study involved outpatient hemodialysis. PARTICIPANTS: We recruited 30 stable hemodialysis patients without a history of frequent diarrhea. INTERVENTION: After receiving informed consent, we randomized patients 2:1 to magnesium carbonate versus calcium acetate. The dose of each binder was titrated to achieve the Kidney Disease Outcomes Quality Initiative (K/DOQI) phosphate target of <5.5 mg/dL. MAIN OUTCOME MEASURE: The efficacy-phase serum phosphorus concentration and the percentage of patients meeting K-DOQI targets for phosphorus, along with the daily elemental calcium intake, were the primary outcome measures. RESULTS: Magnesium carbonate provided equal control of serum phosphorus (70.6% of the magnebind group and 62.5% of the calcium acetate group had their average serum phosphorus within the K-DOQI target during the efficacy phase), while significantly reducing daily elemental calcium ingestion from phosphate binders (908 +/- 24 vs. 1743 +/- 37 mg/day, P < .0001). CONCLUSION: Magnesium carbonate was generally well-tolerated in this selected patient population, and was effective in controlling serum phosphorus while reducing elemental calcium ingestion. 相似文献
19.
Michael B. Farnell Gerard V. Aranha Yuji Nimura Fabrizio Michelassi 《Journal of gastrointestinal surgery》2008,12(4):651-656
With improvements in the safety of Whipple resection in recent decades, surgeons have continued to explore the role of more
extensive lymphadenectomy in hope of improving long-term survival. A systematic literature search of level I evidence addressing
the role of the extent of lymphadenectomy was undertaken. Only reports of prospective, randomized controlled trials comparing
pancreaticoduodenectomy with standard lymphadenectomy to pancreaticoduodenectomy with extended lymphadenectomy where information
regarding survival, morbidity, mortality, the number of resected lymph nodes in each group and detailed operative technique
were included. Four prospective, randomized trials comprising some 424 patients and one meta-analysis were identified. In
aggregate, these studies confirmed that the number of resected lymph nodes was significantly higher in the pancreaticoduodenectomy
with extended lymphadenectomy group. Morbidity and mortality rates were comparable. Postoperative diarrhea in the early months
after operation was problematic in patients undergoing extended lymphadenectomy. In none of the studies was a benefit in long-term
survival demonstrated. Standard pancreaticoduodenectomy continues to be the operation of choice for adenocarcinoma of the
head of the pancreas.
Presented at The Society for Surgery of the Alimentary Tract Postgraduate Course “Systematic Reviews of Pancreaticobiliary
Disease Customized for the Gastroenterologist and Gastrointestinal Surgeon” on May 20, 2007, Washington, D.C. 相似文献
20.