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961.
Sphincter of Oddi stenosis: diagnosis using hepatobiliary scintigraphy and endoscopic manometry 总被引:3,自引:0,他引:3
To determine the role of radionuclide imaging in diagnosing sphincter of Oddi stenosis, 21 patients with symptoms suggesting this disorder underwent endoscopic retrograde cholangiopancreatography, cholescintigraphy, and, when possible, endoscopic manometry. Those patients with abnormal hepatobiliary scintigraphy results--based on our criteria of delayed biliary intestinal transit, abnormal duct size, and abnormal time-activity dynamics and obstruction--had a mean basal sphincter pressure of 38.5 mm Hg. Sphincter pressures could not be measured in six patients with sphincters too tight to cannulate. Ten patients who underwent hepatobiliary scanning both before and after sphincter surgery had normal scan results on the repeat study. Hepatobiliary imaging appears useful for diagnosis of sphincter of Oddi stenosis in selected patients in whom manometry cannot be performed and for objective assessment of response to therapy. 相似文献
962.
Erythrocytes must have the capacity to undergo marked membrane deformation and shape changes in order to circulate through capillaries and respond to a range of shear stresses. To study the interrelationships between membrane deformability and the capacity for shape transformation, we created rigid membranes using several agents and then examined the ability of these erythrocytes with rigid membranes to undergo amphipath-induced shape change. We have previously shown that wheat germ agglutinin (WGA) and a monoclonal antibody to glycophorin A (R-10) cause membrane rigidity as measured by ektacytometry. Experiments were therefore designed to produced comparably rigid membranes using WGA, R-10, and diamide, and then to test the ability of lysophosphatidylcholine to produce echinocytes, and primaquine to produce stomatocytes. We found that diamide treatment substantially blocked both types of shape change. In contrast, R-10 binding did not impair either primaquine- or lysophosphatidylcholine- induce shape change. Further, WGA blocked echinocyte transformation, as previously reported, but not stomatocytosis. Using reduced and unreduced gel electrophoresis and Triton extraction, we compared the biochemical changes associated with WGA-, diamide-, and R-10-induced rigidity, and found them to be different. We conclude that not all rigid cells are incapable of shape change, and therefore that decreased membrane deformability is not predictive of impaired capacity for shape change. 相似文献
963.
By means of a qualitative study, we set out to generate hypothesesabout the way general practitioners (GPs) diagnosed dementia.We looked for triggers for the diagnosis of dementia. Ten GPswere interviewed about four dementia cases taken from theirown practices. GPs are more concerned with treatment than withthe diagnosis of dementia as such, as diagnosis is performedin relation to treatment. The most important aid was the evolutionof the clinical tables based on the information of caregivers.Important triggers were changes of activities of daily lifefunction, behaviour and cognition. Acute illness and loss ofthe key caregiver were relevatory moments. Recommendations aremade for the improvement of the diagnostic abilities of GPs. 相似文献
964.
Mônica Fernandes Gomes DDS MD PhD Daniela Coelho Rangel Cláudia Cristina Morais Starling MD Maria Graças Vilela Goulart MS DDS 《Special care in dentistry》2006,26(3):106-110
The clinical, radiological, pathological and laboratory findings of two brothers with autosomal recessive malignant osteopetrosis are presented. Our findings are similar to characteristics previously reported in the literature about patients with osteopetrosis. The 6‐year‐old male patient was pale and had petechiae on his arms and legs. He also had macrocephalia, splenomegaly, severe pancytopenia, genu valgus, hypocalcemia, amaurosis, cessation of physical development, generalized bone sclerosis and recurrent infections with a history of multiple incidences of acute otitis media. Generalized bone sclerosis and irregular sclerosis of the maxilla and mandible were seen on radiographs. The oral mucosa was apparently normal but permanent tooth eruption was delayed although there was early loss of deciduous teeth. The recommended treatment was blood transfusion and therapy with antibiotics when necessary; a bone marrow transplant was not possible due to lack of a compatible donor. 相似文献
965.
A 7 month old infant with pancreatitis and ascites was managed successfully with subcutaneous octreotide and external drainage of a pseudocyst. An endoscopic retrograde cholangiopancreatographic examination showed no congenital abnormality and was consistent with chronic pancreatitis. Octreotide has a possible therapeutic role in pancreatic ascites. 相似文献
966.
Psychological mechanisms of enhanced risk of addiction in children of alcoholics: a dual pathway? 总被引:1,自引:0,他引:1
The background and rationale of a recently started project of the Amsterdam Institute for Addiction Research are outlined. This project is aimed at the psychological mechanisms underlying an enhanced risk of (later) addiction in children of alcoholics and the relationship with childhood psychopathology. A dual pathway mechanism is proposed, in which the type of alcoholism of the parent plays a major role. The child of a multigenerational primary alcoholic parent may suffer from an inherited mild dysfunction of the prefrontal cortex, expressed in neuropsychological and personality characteristics similar to those of the alcoholic parent. These are impulsive, aggressive and reward-seeking behaviour, response perseveration and, in some children, related psychopathology such as conduct disorders. For a child of a secondary alcoholic parent, another mechanism is proposed. In these children, stress and social learning may lead to negative affectivity and repressive coping style, with emotional problems at a later age, and the risk of falling into the "circle of secondary alcoholism". In both pathways, alcohol-related expectancies are suggested to constitute a "final common pathway" between different risk factors and later alcohol abuse. Specific expectancies might be related to different pathways and to gender differences in later drinking patterns. 相似文献
967.
NIHAL U OBEYESEKERE JEAN-NOEL LA CROIX RAYMOND JA BUDDE DOUGLAS F DYCKES JOHN S. MCMURRAY 《Chemical biology & drug design》1994,43(2):118-126
(Tyr-Ala-Glu)n, n= 1–9, were synthesized by segment condensation using the Fmoc/tert-butyl protection strategy and solid-phase techniques. The C-terminal residue was coupled to the resin and the peptides were built out by adding Fmoc-Glu(O-r-Bu)-Tyr(t-Bu)-Ala-OH units. When the desired lengths were reached the peptides were capped with Fmoc-Tyr(t-Bu)-Ala-OH units. Fmoc-Tyr(t-Bu)-Ala-OH and Fmoc-Glu(O-t-Bu)-Tyr(t-Bu)-Ala-OH were synthesized in aqueous solution by the successive addition of N-hydroxysuccinimide esters of Fmoc-Tyr(t-Bu) and Fnioc-Glu(0-t-Bu) to the growing chain. Neither sequential amino acid addition or segment condensation techniques were successful on polystyrene supports. However, the segment condensations were highly successful on kieselguhr-supported polydimethylacrylamide based resins. (Tyr-Ala-Glu)n, n= 1–9, were tested as inhibitors of the protein [yosine kinase, pp60Cc-src. Inhibition, as measured by IC50 values, increased with increasing size of the peptide. 相似文献
968.
The expression of α1-adrenoceptor subtypes in several tissues is regulated by gonadal hormones. In this study, we investigated whether castration regulates the α1-adrenoceptor subtypes mediating the contractions of the aorta from male rats to noradrenaline. Noradrenaline induced similar concentration-dependent contractions in the aorta from control and castrated rats. Treatment of the aorta from both control and castrated rats with the α1B/α1D-adrenoceptor alkylating agent chloroethylclonidine resulted in ≈1600-fold rightward shift in the concentration–response curves to noradrenaline. The pA2 values found for WB 4101, benoxathian (α1A-selective) and BMY 7378 (α1D-selective) indicate that α1D-adrenoceptors are involved in the contractions of the aorta from control and castrated rats to noradrenaline. However, there was a 15-fold difference between the pKB estimated through the lowest effective concentrations of the α1A-adrenoceptor selective antagonist 5-methyl-urapidil in the aorta from control and castrated rats. The pKB estimated in aorta from control rats is consistent with the interaction with α1D-adrenoceptors (7.58±0.06), while that calculated in organs from control rats is consistent with α1A-adrenoceptors (8.76±0.09). These results suggest that castration induces plasticity in the α1-adrenoceptor subtypes involved in the contractions of the aorta to noradrenaline. 相似文献
969.
JA Cairns MD 《International journal of clinical practice》1998,52(6):422-424
SUMMARY Many deaths among hospital survivors of acute myocardial infarction are due to sustained ventricular tachycardia and ventricular fibrillation. This has prompted the evaluation of prophylactic antiarrhythmic drugs and devices. Although it is widely agreed that antiarrhythmic treatment is useful, it is not certain which therapy provides optimal results. Increasing recognition of the efficacy of amiodarone has prompted the design of several trials of the drug. This paper focuses on primary prophylactic antiarryhthmic therapy in the post-infarction setting and particularly on recent amiodarone trials. 相似文献
970.