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991.
Although stimulation of PRL secretion in the early postpartum period has been found to improve lactational performance, the effect of chronic maintenance of elevated plasma PRL levels on milk production is not known. In a randomized design, 66 lactating women were assigned to receive either a placebo (n = 32) or the dopamine antagonist sulpiride (n = 34; 100 mg, three times daily), for 4 days, followed by 50 mg, three times daily, for a 90-day period). Their basal and 30 min postsuckling plasma PRL levels as well as the weights of their infants were measured 1, 4, 15, 30, 60, and 90 days postpartum. Forty-one women (20 sulpiride-treated and 21 placebo-treated) completed the study. Compared with the placebo group, which had the expected postpartum plasma PRL decline, the sulpiride-treated women maintained significantly elevated basal plasma PRL values up to the 90th postpartum day. In contrast, the postsuckling plasma PRL level was significantly diminished in the latter group, and on day 90 was practically absent. On day 15, weight gain was significantly greater in the infants whose mothers received sulpiride, but later, no differences were detectable between groups of infants despite the disparity in PRL levels in their mothers. We conclude that enhancement of PRL secretion in the early postpartum period may transiently increase milk production, but chronic hyperprolactinemia has no effect on lactational performance. The plasma PRL response to suckling is not essential for the maintenance of milk secretion. Instead, basal plasma PRL levels and neurogenic reflexes may be more instrumental in maintaining established lactation.  相似文献   
992.
BACKGROUND: Significant progress has been made in clinical small bowel transplantation over the last decade mainly due advances in biotechnology and new immunosuppressive regiments. This transplantation has now been indicated to treat special cases of intestinal failure. AIM: This review highlights recent developments in the area of small bowel transplantation. MATERIAL AND METHODS: Over 600 reports on clinical and experimental small bowel transplantation were reviewed. Aspects concerning research development, different immunosuppressive strategies, patient and graft monitoring, and improvements in surgical techniques are discussed. RESULTS: About 700 small bowel transplantation were performed in 55 transplant centers, 44% intestine-liver, 41% isolated intestinal graft and 15% multivisceral transplantation. Rejection and infection are the main limitation of this procedure. Actual 5 years post transplantation graft survival of the total international experience is 46% for isolated intestinal graft, 43% for combined intestine-liver and nearly 30% for multivisceral transplantation. Higher graft and patient survival are seen at the more experienced centers. In a series of 165 intestinal transplantation at University of Pittsburgh, PA, USA, actuarial patient survival was reported to be over 75% at one year, 54% at 5 years and 42% at 10 years. Over 90% patients from Pittsburgh program resume an unrestricted oral diet. CONCLUSION: Small bowel transplantation has advanced from an experimental strategy to a feasible alternative for patients with permanent intestinal failure. Further refinements in graft acceptance, immunosuppressive regiments, infection management and prophylaxis, surgical techniques as well as appropriated patient referral and selection are crucial to improve outcomes.  相似文献   
993.
AIMS: New interventional techniques to diagnose coronary artery stenosis, such as calculation of myocardial fractional flow reserve (FFR) with a guidewire and pressure transducer, provide a functional assessment of coronary lesions. The present study was designed to investigate the occurrence of cardiac events in patients with coronary syndromes and negative FFR findings in moderately severe coronary stenosis in order to determine the usefulness of this technique in predicting coronary events during follow-up for problems commonly encountered in clinical practice. A further objective was to evaluate the safety of deferring angioplasty in patients with a negative FFR result. METHODS: We studied 43 patients with 44 moderately severe coronary artery stenoses on angiography and FFR > or = 0.75. Mean age of the patients was 58 +/- 11.4 years. The indications for coronary angiography included recent unstable angina in 24 (55.8%) patients, recent acute myocardial infarction in 10 (23.2%) patients, 5 (11.6%) patients with a coronary stent who had symptoms of uncertain cause, and stable angina in 4 (9.3%) patients. RESULTS: During a mean follow-up period of 10.7 +/- 5.9 months, clinical events (unstable angina) occurred in five patients. In three patients, the initially investigated artery was involved, and in the two patients who required coronary revascularization, unstable angina was related with an artery different from the one studied initially. CONCLUSIONS: Patients with recent coronary syndromes and negative FFR findings in moderately severe coronary stenosis were unlikely to have cardiac events during a 10-month follow-up period. Our findings suggest that FFR is a potentially useful indicator of the likelihood of cardiac events and thus represents a useful aid in clinical decision-making in the hemodynamics laboratory. This diagnostic technique also is potentially useful in identifying patients for whom angioplasty can be safely deferred.  相似文献   
994.
995.
Recently, reactivation of Chagas disease (meningoencephalitis and/or myocarditis) was included in the list of AIDS-defining illnesses in Brazil. We report a case of a 52-year-old patient with no history of previous disease who presented acute meningoencephalitis. Direct examination of blood and cerebrospinal fluid (CSF) showed Trypanosoma cruzi. CSF culture confirmed the diagnosis. Serological assays for T. cruzi and human immunodeficiency virus (HIV) were positive. Despite treatment with benznidazol and supportive measures, the patient died 24 hours after hospital admission. In endemic areas, reactivation of Chagas disease should always be considered in the differential diagnosis of meningoencephalitis among HIV-infected patients, and its presence is indicative of AIDS.  相似文献   
996.
OBJECTIVE: To evaluate feasibility, safety, and efficacy of peripheral blood stem cell collection (PBSCC) and autologous stem cell transplantation (ASCT), to treat patients diagnosed of high-risk or relapsed HIV-associated lymphoma (HIV+ Ly), responding to highly active antiretroviral therapy (HAART). METHODS: Prospective and multicentric study in patients with high-risk or relapsed chemosensitive HIV+ Ly, candidate for consolidation with ASCT. Eligibility criteria were similar to those of HIV- lymphoma. HAART was aimed to be maintained during the procedure. RESULTS: Fourteen patients were admitted. Adequate PBSCC was obtained from all patients (median CD34+ cells was 4.7 x 10(6)/kg). Three patients died before ASCT; two had disease progression and one died from VHC-liver failure. Eleven transplanted patients showed neutrophil engraftment after a median time of 16 days (range, 9-33 days), and nine patients showed platelet engraftment after a median time of 20 days (range, 11-36 days). CD4+ cell counts and HIV viral load (VL) were appropriately preserved along the procedure. No patients died from treatment-related complications. One patient died from lymphoma progression (day +19), and another died in complete remission (CR) with undetectable VL, 15 months after transplant, due to infection. One patient relapsed at 32 months after ASCT. The remaining eight patients are alive in CR with an event-free survival of 65% and a median follow-up of 30 months after ASCT (range, 7-36 months). CONCLUSIONS: These results show that feasibility, safety, and efficacy of PBSCC and ASCT in HIV+ Ly patients responding to HAART are similar to those observed in the HIV- lymphoma setting.  相似文献   
997.
A 40-year-old woman on chronic hemodialysis had been diagnosed as having lepromatous leprosy at the age of 17 and treated for 15 years with sulfones. She remained clinically free of leprosy during 19 months of hemodialysis and then underwent successful renal transplantation. Fourteen months after surgery, recurrence of leprosy was observed. In spite of immunosuppression, the skin lesions healed with sulfone treatment. Renal transplantation is a useful treatment in patients with leprosy and chronic renal failure.  相似文献   
998.
Necrotizing fasciitis is a rare soft tissue infection and a life-threatening emergency, often fatal. Its incidence and management are described plentifully in the medical literature regarding the most common anatomical sites involved like the abdomen, lower and upper limbs, and perineum. However, available data and case reports of chest wall necrotizing fasciitis after thoracic procedures are scarce, mainly after major cardiac operations. We report and discuss a case of necrotizing fasciitis of the chest wall occurring in the immediate postoperative period of a cardiac procedure, and include a brief review of the concepts, pathophysiology, and treatment reported in the medical literature. We emphasize the need for early diagnosis and urgent and effective surgical debridement. Of importance is the fact that we have not found any references in the literature to cases similar or equal to the one we describe here, which occurred in the postoperative period of a cardiac procedure.  相似文献   
999.
Summary Cell-mediated immunity and cytokines are probably involved in the pathogenesis of malaria. To investigate the role and the activity of different immune cells, we measured levels of tumour necrosis factor-(TNF-α), gamma interferon (IFN-γ) and several interleukins (IL-2, IL-4, IL-6 and IL-10) in children with mild (MM) and cerebral (CM) Plasmodium falciparum malaria and compared them with those of healthy children from Guadalupe - Lobata District, St. Tomé Island, where malaria is mesoendemic. Both groups of patients had significantly higher levels of IL-6, IL-10 and TNF-α than controls. For IL-2, IL-4 and IFN-γ we found no difference between the groups. However, 24 h after admission the levels of IL-10 and IL-6 were significantly higher in CM than in MM patients, although 7 days after treatment they returned to normal levels, similar to those found in control children. Therefore, TNF-α IL-6 and IL-10 increase during Plasmodium falciparum attacks in all children, not only in those with cerebral malaria. This finding suggests the activation of the monocyte/macrophage system during the early stage of clinical malaria.  相似文献   
1000.
Experimental infection of marmoset monkeys (Callithrix jacchus) with Leptospira interrogans serovar Copenhageni showed microscopic patterns of tissue reactions comparable to those seen in the severe forms of human leptospirosis, including intra-alveolar hemorrhage. The most impressive microscopic changes were seen in the lung and kidney of animals killed at days 6 and 12 after inoculation. There were extensive and irregular areas of hemorrhage predominating around main bronchial branches or diffusely spread to the pulmonary parenchyma, as well as severe tubulointerstitial nephritis. Antibody response detected by the microscopic agglutination test was quantitatively similar to those seen in humans and paralleled severity of tissue lesions. The distribution of leptospires or antigenic debris in infected tissues was observed by immunofluorescence and confocal laser scanning microscopy. Large numbers of typical leptospires were seen in the lumen of proximal renal tubules. Positive reactions showing antigenic debris were closely associated with sites of tissue damage.  相似文献   
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