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排序方式: 共有4796条查询结果,搜索用时 15 毫秒
991.
Energy expenditure was studied in ten patients with chronic obstructive pulmonary disease (COPD) and weight loss, and in five malnourished patients without clinical evidence of COPD (control group) prior to and after a two-week refeeding regimen. Patients received 5 percent dextrose solution (plus electrolytes) for 36 hours to establish standard baseline conditions and were then randomly assigned to either a carbohydrate-based (CB; 53 percent of calories) or fat-based (FB; 55 percent of calories) diet for the first week. The alternate diet was given the following week. Total calorie intake was set at 70 percent above the energy expenditure measured prior to institution of nutritional support. During energy repletion, energy expenditure was greater than predicted (116 percent) in patients with COPD and less than predicted (90 percent) in the control patients. Thermic effect of nutrients during administration of either regimen was significantly greater (p less than .05) in patients with COPD than in those without COPD during both diets. The difference between the two groups was enhanced during the CB regimen. These observations suggest that malnourished patients with COPD have an elevated resting energy expenditure, and an enhanced thermic response to nutrients as compared to malnourished patients without COPD. Increased diet-induced thermogenesis may contribute to weight loss in patients with COPD, in addition to factors previously described such as decreased caloric intake and increased resting energy expenditure. 相似文献
992.
Injections of 3,4-methylenedioxymethamphetamine (MDMA, 25 mg/kg, i.p.) to rats lead to an accumulation of c-fos protein (Fos) and Fos-related antigens in caudate-putamen, nucleus accumbens and olfactory tubercle. This induction occurred at least 2 h (but not at 10 min) after injection and Fos levels had returned to baseline after 24 h, although Fos-related antigens remained elevated 24 h after injection. The NMDA antagonist MK 801 inhibited Fos and Fos-related antigen induction after MDMA injections, whereas fluoxetine, a serotonin uptake inhibitor, had no effect. Thus, MDMA induces Fos and Fos-related antigens in striatal neurons in an NMDA-reversible fashion. 相似文献
993.
The ganglion is the most common soft tissue tumor of the hand and wrist, originating from the joint capsule or tendon sheath. Accurate diagnosis and proper treatment of these entities require a thorough knowledge of the anatomy of the wrist and hand as well as of the ganglion itself. Definitive therapy is based on total surgical removal of the cyst and its connections to the joint or tendon sheath. 相似文献
994.
995.
J M Elwood J C Pearson R J Madeley R F Logan M W Beaver P A Gillies J Little A Langham 《Journal of epidemiology and community health》1986,40(3):232-235
Medical students in Nottingham all complete an honours Bachelor of Medical Sciences course in one department including a research project. The honours programme in community health is described, with results from a survey of the 122 graduates since the medical school started. The 98 (80%) responses showed high levels of satisfaction and gain from the programme, the great majority regarding the course as valuable, enjoyable, and giving both research skills and skills in interpersonal relationships. 相似文献
996.
Blunt injuries of the thoracic aorta. 总被引:4,自引:0,他引:4
A D Hilgenberg D L Logan C W Akins M J Buckley W M Daggett G J Vlahakes D F Torchiana 《The Annals of thoracic surgery》1992,53(2):233-8; discussion 238-9
We managed 51 patients with thoracic aortic injuries caused by blunt trauma between 1977 and 1990. Forty-nine injuries were located in the upper descending aorta and one each in the ascending aorta and aortic arch. Three patients arrived moribund and underwent thoracotomy for resuscitation, and all died. The diagnosis was confirmed by aortography in 48. One patient died of aortic rupture, 1 died of hypoxemia, and 1 refused operation and died. Forty-four patients had aortic repair, 42 with graft insertion. Gott shunts were placed in 23 with 3 cases of paraplegia (13%). Simple cross-clamping was used in 19 with 1 case of paraplegia (5.2%). We found statistically significant differences between the cross-clamp times of patients without paraplegia compared with those in whom paraplegia developed in both the shunt and no-shunt groups. Logistic regression analysis showed that the only factor significantly associated with paraplegia was cross-clamp time. There were two postoperative deaths (4.4%). Seven patients had medical therapy initially and aortic repair was delayed to allow other injuries to stabilize. Before aortic repair, 18 patients had intraarterial pressure monitoring and 34 received beta-blockers or antihypertensive drugs. We conclude that aortic repair with graft insertion is usually successful in nonmoribund patients, simple cross-clamping is associated with a relatively low risk of paraplegia, the incidence of paraplegia is directly associated with the duration of cross-clamp time, and selected patients can be managed medically while awaiting aortic repair. 相似文献
997.
Hypomagnesaemic tetany (hypomagnesaemic tetany with secondary hypocalcaemia) is a rare inherited form of hypomagnesaemia. Initial reports involved affected males only; however, affected females have also been reported. The case of a child with hypomagnesaemic tetany is described, the biochemical and genetic aspects of this condition are reviewed and the importance of the assessment of renal magnesium excretion in patients presenting with hypomagnesaemia is highlighted. 相似文献
998.
G B MacPhee R W Logan J S Mitchell D W Howells E Tsotsis D R Thorburn 《Archives of disease in childhood》1993,69(4):433-436
Two new cases of malonyl coenzyme A (CoA) decarboxylase deficiency are described. Hitherto, the worldwide experience of the disorder has been confined to reports on two affected Australian children. The new cases are Scots born and are the offspring of consanguinous parents of Scots/Irish origin. They were investigated during episodes of vomiting and febrile convulsions associated with concomitant developmental delay. Malonic aciduria and grossly reduced malonyl CoA decarboxylase activity were demonstrated and the total ion current chromatograms of urinary organic acid profiles obtained by gas chromatography-mass spectrometry are presented. The clinical and biochemical features of the Scots and Australian patients are compared. 相似文献
999.
Coccidioidomycosis is the most common endemic mycosis to cause disease in solid-organ transplant patients in North America. Underlying renal and liver disease, T-lymphocyte suppression from antirejection medication, and activation of immunomodulating viruses, such as cytomegalovirus, all increase the risk for coccidioidomycosis among these patients. About one half of all cases are the result of reactivation of previously acquired coccidioidal infection and occur during the first year after transplantation. Although disseminated infection is common, most cases manifest pulmonary symptoms. Culture of pulmonary secretions from bronchoscopy is frequently diagnostic. Serologic tests are particularly useful for identifying patients who are at high risk for reactivating coccidioidomycosis posttransplantation. Amphotericin B and azoles are the mainstay of therapy. Although there are no established approaches to preventing coccidioidomycosis among these patients, studies are underway examining the use of prophylactic azole antifungals with documented prior coccidioidal infection. 相似文献
1000.