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991.
Analysis of neonatal, perinatal and infant mortality rates is a useful basis to compare the quality of neonatal care in a country. During the last decades these parameters have been falling steadily in Austria as well as in other industrialized countries. Regarding the various provinces of Austria substantial regional differences occur. Apparently the decline in mortality rates is not only contributable to medical progress but as strongly influenced by social and economic changes. In the mid-seventies absolute and relative neonatal mortality rates in Austria definitely decreased, most probably attributable to the installation of neonatal intensive care units. During 1968-1978 the decrease in neonatal mortality was mainly due to reduced first-day-mortality, whereas during the following decade it was mainly due to reduced mortality of the 2nd until 7th day of life. Interestingly, the rate of preterm infants in Austria remained virtually constant during 1968-1988 despite improved pre- and perinatal care. Paralleling the development in full-term neonates the peri-/neo- and postneonatal mortality rates of preterm infants decreased. Predictably - as in other countries - the highest improvement was found in the low birth weight groups Nevertheless, premature births have accounted for the majority of neonatal and perinatal deaths. 相似文献
992.
Marie-Francoise Dresse Michele David Heather Hume Herve Blanchard Pierre Russo Nicolas Van Doesberg Georges E. Rivard 《Pediatric hematology and oncology》1991,8(4):329-334
The Kasabach-Merritt syndrome is characterized by thrombocytopenia and localized coagulopathy associated with a hemangioma. Most techniques applied to eradicate the tumor or accelerate its involution (surgery, radiation therapy, embolization) are invasive and require transfusion of large amounts of blood products. In some cases, medical treatment is the only alternative. Efficacy of steroids and antifibronolytic agents has already been described, but even this approach is associated with the administration of blood products. We report two cases of infants with Kasabach-Merritt syndrome associated with cardiac and hepatic hemangiomas. At admission, both had signs of cardiac failure. They were successfully treated with prednisone and epsilon-aminocaproic acid (EACA). Blood products were not required once the diagnosis was made. These observations have important implications for the management of patients with Kasabach-Merritt syndrome because they show that even in severe cases blood transfusions can be avoided by the use of prednisone and EACA. 相似文献
993.
David W. Smith 《Statistics in medicine》1994,13(10):1001-1013
The variation in mortality rates among hospitals has often been described informally as having three major components: patient severity, quality of care and random variation. These informal concepts are characterized formally by partitioning sums of squares and finding their expected values. The partition relates to commonly used tests for whether individual hospitals have unusual mortality rates. Application of the partition to the hospital mortality reports by the Health Care Financing Administration shows that their models for patient risk account for about one-half the variation among hospital mortality rates. An example using clinical measures of severity accounts for about two-thirds of mortality variation among hospitals. 相似文献
994.
Philip J. Larsen David S. Jessop Hardial S. Chowdrey Stafford L. Lightman Jens D. Mikkelsen 《Journal of neuroendocrinology》1994,6(2):153-159
The complete sequence of the cDNA encoding the neuropeptide Y (NPY) Y1-receptor has recently been deduced from a rat brain library, and the presence of messenger ribonucleic acid (mRNA) encoding Y1-receptor protein has been demonstrated within the brain. Using quantitative in situ hybridization histochemistry, the content and distribution of Y1receptor and preproNPY mRNAs have been investigated in the hypothalamic arcuate nucleus of adrenalectomized rats receiving glucocorticoid replacement therapy for 12 days by means of either high doses of dexamethasone in their drinking water or by subcutaneous corticosterone pellets. Basal metabolic parameters such as weight gain or loss, blood glucose and plasma insulin were monitored: Dexamethasone treatment induced weight loss and a state of hyperinsulinemia with normoglycemia, while corticosterone treated animals displayed metabolic parameters identical to sham ADX animals. Within the arcuate nucleus of glucocorticoid treated animals, levels of Y1receptor and preproNPY mRNAs were increased. In contrast, adrenalectomy itself had no effect upon Y1-receptor mRNA levels or preproNPY mRNA levels in the arcuate nucleus. These studies demonstrate that glucocorticoids exert a stimulatory action on levels of Y1-receptor mRNA and preproNPY mRNA levels in the hypothalamic arcuate nucleus. This is the first evidence to suggest that the expression of a neuropeptide-receptor gene in the central nervous system may be directly sensitive to peripheral hormonal signals. 相似文献
995.
996.
This study investigated the release of nitric oxide (NO) from glyceryl trinitrate (GTN) and SIN-1 in Langendorff rabbit hearts. Infusion of either GTN (10-40 microM) or SIN-1 (0.45-4.5 microM) into the coronary inflow tract resulted in a decrease in coronary perfusion pressure and NO release (oxyhemoglobin technique) into the coronary effluent. NO release from SIN-1 occurred spontaneously whereas passage through the coronary circulation, i.e. active metabolism, was required for NO release from GTN. Removal of the coronary endothelium and blockade of endothelial NO formation did not affect NO release from GTN and SIN-1. In GTN-tolerant hearts, there was a considerable inhibition of GTN- but not SIN-1-induced NO formation and coronary vasodilation. These data suggest (1) that metabolic NO release from GTN occurs during passage of the coronary circulation and is independent of the presence of endothelium, and (2) reduced NO release is a major cause of nitrate tolerance. 相似文献
997.
M Scheininger J Dziersk W Kullak A Kors J A K?hler K Theisen 《Zeitschrift für Kardiologie》1991,80(10):630-636
We studied the effect of barucainide, an investigational class lb antiarrhythmic drug, on ventricular arrhythmias and left-ventricular ejection fraction in 10 patients with frequent and complex ventricular arrhythmias (Lown grade 4a/4b). The study was conducted as a single-blind and placebo-controlled trial. With placebo, mean frequency of ventricular arrhythmias was 6238 VPB/24 h, 510 couplets/24 h, and 24 salvos/24 h. Mean left-ventricular ejection fraction was 37.6%, ranging from 18% to 58%. Therapy with barucainide (300-400 mg/day) resulted in a significant reduction of ventricular arrhythmias in 7 of 10 patients; in one patient barucainide had a clear proarrhythmic effect. Over all, left-ventricular ejection fraction (37.6% +/- 12% with placebo vs 36.1% +/- 11% with barucainide) was not significantly altered. In one patient, however, it was depressed by more than 5%; one patient complained of shortness of breath during exercise. None of the four patients with an initial ejection fraction below 35% showed a drop of ejection fraction during therapy with barucainide. The only main adverse effect was a small, but significant (p less than 0.005) rise of serum-kreatinine (1.13 +/- 0.26 vs 1.39 +/- 0.38 mg%) in all patients. We conclude that barucainide has a good antiarrhythmic effect and is usually well tolerated in patients with markedly depressed left-ventricular function. The mechanism causing the rise of serum-kreatinin, however, needs to be clarified in further studies. 相似文献
998.
Following the pioneering work of Ross and Barratt-Boyes, there is currently a strong evidence based on long-term follow-up data that valve homografts are the best valve substitutes in the aortic position. Currently there exists a renewed interest in the use of fresh and cryopreserved homografts as we know that homografts show a prolonged durability together with the lack of thromboembolic complications. Here we present the case histories of 3 patients undergoing aortic valve replacement by fresh homografts sterilized in antibiotic solution. The underlying pathology was infective endocarditis in all 3 patients, a disease that is considered the ideal indication for homograft implantation. Technical details at the time of implantation, their advantages with regard to other replacements devices and the whole process of procurement, manipulation and preservation are commented on. 相似文献
999.
Michael L. Graham Jonathan J. Shuster Barton A. Kamen David L. Cheo Matthew P. Harrison Brigid G. Leventhal D. Jeanette Pullen V. Michael Whitehead 《Cancer chemotherapy and pharmacology》1992,31(3):217-222
Summary We enrolled children with acute lymphoblastic leukemia (ALL) in a Pediatric Oncology Group (POG) pilot study to monitor erythrocyte (RBC) methotrexate (MTX) and folate (F) levels before and during treatment. The mean value for RBCF at diagnosis was 0.86±0.46 nmol/ml RBC in the 214 patients who achieved remission and 1.21±0.74 nmol/ml RBC in the 10 patients who did not (P=0.020). Folate levels tended to increase during remission induction, but they dropped following an intensive consolidation with methotrexate to levels that were sustained throughout chemotherapy treatment. Methotrexate levels reached mean values of approximately 0.15 nmol/ml RBC at the end of an intensive methotrexate consolidation, then fell to levels that were sustained throughout maintenance therapy. There was a weak correlation between improved event-free survival and higher RBCMTX levels after consolidation, but no correlation was found between improved survival and the level of RBCMTX or RBCF during maintenance therapy. A larger study with more complete data is needed to determine whether RBCMTX or RBCF might be useful in predicting event-free survival in patients with ALL.This work was supported in part by grants from the National Cancer Institute and the National Institute of Health (CA-30969, CA-28476, CA29139, CA-159-89, and CA-33587) 相似文献
1000.
Serological surveys in Norway have demonstrated neutralising antibodies against bovine virus diarrhoea (BVD) virus in cattle, sheep and goats. The prevalences were 18.5%, 4.5% and 3.6%, respectively. Occurrence of pestivirus-induced disease in Norway is described. Outbreaks of reproductive failure and mucosal disease have been reported, and the number of persistently-infected animals detected has increased considerably in recent years. Acute BVD occurs rarely. Border disease (BD) in sheep, first diagnosed in 1981, has subsequently been demonstrated sporadically. In goats, typical BD was diagnosed in 1982, with three later occurrences of reproductive failure. Experimental infections in pregnant goats induced a high rate of severe foetopathogenic effect. Signs and lesions in offspring were comparable to ovine BD. Similar findings were demonstrated in goats given a pestivirus-contaminated vaccine. In newborn kids, experimental infection had an adverse influence on growth and health. Persistent infection in goats is probably rare. 相似文献