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991.
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994.
Management of rectal injuries. Dogma versus practice 总被引:2,自引:0,他引:2
The current treatment of civilian rectal injuries stems from military practice. Five principles have evolved: 1) complete fecal diversion, 2) debridement and closure, 3) rectal stump irrigation, 4) presacral drainage, and 5) broad spectrum antibiotics. To assess our practice results, the records of 52 consecutive patients with rectal injury seen at Detroit Receiving Hospital from 1980-88 were reviewed. Etiologies were gunshot (40), shotgun (9), anal assault (2), and stab (1). There were no blunt injuries and no deaths. Treatment consisted of celiotomy (52), diverting colostomy (51), presacral drains (35), rectal stump irrigation (26), and primary closure (1). Broad spectrum antibiotics were administered in all patients. Despite lack of universal application of the "standard" principles, only five patients had postoperative complications and none were related to the rectal injury. Our results demonstrate that a single approach may not be justified, as excellent outcome was achieved with low morbidity and no mortality despite selective management. The universal application of colostomy, repair, irrigation, drainage, and antibiotics cannot be supported. 相似文献
995.
The authors report six cases of milk of calcium syndrome. As in previously published cases, the diagnosis was established by the film taken in the standing position: the "lithiasic density" shrinks, densifies and exhibits a horizontal upper edge. Four patients were at first mistakenly diagnosed as having urinary lithiasis for which extracorporeal lithotripsy was scheduled. In one case, the lithotripsy was actually performed and the diagnosis of milk of calcium disease was established only immediately after the procedure. In another patient, lithotripsy was performed because small stones were thought to be present in the milk of calcium. In the two other cases, the diagnosis was made on the day before scheduled lithotripsy and this procedure was therefore cancelled. The purpose of the authors in reporting these cases is above all to point out the diagnostic value of a plain film of the abdomen in the standing position. Diagnosis must be made in time to avoid extracorporeal lithotripsy since, in milk of calcium syndrome, this procedure is illogical, inefficient and probably more hazardous than useful. On the basis of the six cases reported herein and of data from the literature, several characteristics of milk of calcium syndrome can be emphasized. Milk of calcium syndrome predominantly affects individuals with a positive personal or family history for renal lithiasis. It occurs in both sexes and all age groups, including childhood. Milk of calcium syndrome complicates partial or total dilatation of the urinary tract. Crystallization may be of the phosphatic or oxalic type. Concomitant urinary tract infection is common.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
996.
Hereditary motor and sensory neuropathies and hereditary spastic paraplegia: a magnetic stimulation study 总被引:9,自引:0,他引:9
Central motor conduction to the small hand muscles was investigated in 59 patients with peroneal muscular atrophy and hereditary spastic paraplegia (HSP) by using transcranial magnetic brain stimulation. These comprised 20 patients with type I hereditary motor and sensory neuropathy (HMSN I), 15 with type II (HMSN II), 4 with HMSN I and 10 with HMSN II with associated pyramidal features, and 10 with the "pure" form of HSP. Central motor conduction was usually normal in HMSN I, HMSN II, and HSP. In HMSN I with pyramidal signs, central motor conduction time was greatly prolonged bilaterally. This result may reflect an associated involvement of the central motor pathways in these patients. In HMSN II with accompanying pyramidal features, 6 of the 10 patients had abnormal central motor conduction, although conduction times were only slightly prolonged, suggesting a different pathophysiological pattern. 相似文献
997.
998.
Akman Steven A.; Kensler Thomas W.; Doroshow James H.; Dizdaroglu Miral 《Carcinogenesis》1993,14(9):1971-1974
The mouse skin tumor promoter benzoyl peroxide (BzPO), in conjunctionwith Cu(I), causes promutagenic damage in DNA. Because freeradical intermediates are produced by the reaction of BzPO withCu(I), we sought to determine whether BzPO plus Cu(I) causedDNA base damage typical of that caused by the hydroxyl radical.A broad range of modified DNA bases were measured by GC-MS withselected-ion monitoring after exposure of purified plasmid pCMVßgalDNA to BzPO ± Cu(I). Exposure to BzPO/Cu(I) caused upto 20-fold increases in the levels of adenine-derived modifiedbases, and only a <2-fold increase in thymine-derived modifiedbases. The guanine-derived modified base 8-hydroxyguanine waselevated to the highest net amount, 160 molecules/105 DNA bases.Exposure to BzPO alone or Cu(I) alone induced only minor (<<2-fold) DNA base modification. Also, benzoic acid, the majornon-radical metabolite of BzPO, or BzPO plus Fe(II) were ineffectiveat inducing DNA base modification. The hydroxyl radical scavengerdimethyl sulfoxide inhibited BzPO/Cu(I)-induced base modificationby 1050%. These data suggest that the reaction of BzPOwith Cu(I) generates hydroxyl radical or a similarly reactiveintermediate which causes DNA base damage. This damage may beresponsible for BzPO/Cu(I) mediated mutagenesis. 相似文献
999.
l-Glutamate is the most abundant of a group of endogenous amino acids in the mammalian central nervous system which presumably function as excitatory neurotransmitters and under abnormal conditions may behave as neurotoxins. As neurotransmitters, these compounds are thought to play an important role in functions of learning and memory. As neurotoxins, they are believed to be involved in the pathogenesis of a variety of neurodegenerative disorders in which cognition is impaired. Moreover, brain structures which are considered anatomical substrata for learning and memory may be particularly vulnerable to the neurotoxic actions of these excitatory amino acids, especially in the elderly who are also the segment of the population most susceptible to impairments of mnemonic function. This paper is a review of data concerning the role of excitatory amino acids in the processes of learning and memory and in the pathogenesis and treatment of disorders thereof. 相似文献
1000.
D. B. Thomas 《Advances in Contraception》1993,9(Z1):31-48
Los contraceptivos orales protegen frente al cáncer epitelial ovárico y el cáncer de endometrio. El grado de protección frente a ambos tipos de cáncer aumenta con la duración de su uso y persiste durante más de una década tras la interrupción del tratamiento. El carcinoma hepatocelular, es una consecuencia muy poco frecuente de la utilización de los contraceptivos orales en aquellos países en los que las cifras de frecuencia de esta enfermedad son bajas, pero no se ha demostrado esta complicación en las regiones donde la hepatitis C es endémica y las tasas subyacentes son elevadas. El riesgo de los adenomas celulares hepáticos también es mayor entre las usuarias de los contraceptivos orales. El colangiocarcinoma y el carcinoma de la vesícula biliar no se han asociado con la utilización de los contraceptivos orales. Se ha observado de modo bastante preciso que a mayor duración del empleo de los contraceptivos orales también es mayor el riesgo de aparición de un carcinoma cervical de células escamosas, tantoin situ como invasivo, incluso después de eliminar los posibles efectos confusivos de los exámenes citológicos y el comportamiento sexual de las mujeres estudiadas y sus parejas. El riesgo del adenocarcinoma cervical también se ha asociado con el uso de los contraceptivos orales. El empleo de estos preparados no se ha relacionado con una alteración global del riesgo de cáncer de mama en los estudios en los que se incluyeron mujeres con una amplia variación de edades. Sin embargo, su utilización a largo plazo se ha asociado con un aumento del riesgo del cáncer de mama en mujeres de menos de 45 años. El empleo de los contraceptivos orales no se ha relacionado con el riesgo de aparición del melanoma maligno.Esta publicación está basada en una presentación hecha durante la sesión organizada por la SAC (Sociedad para el Estudio y Progreso de la Anticoncepción) Beneficios y Riesgos de la Anticoncepción Oral' durante el XIV Congreso Mundial de Fertilidad y Esterilidad en Caracas, Noviembre de 1992. 相似文献