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排序方式: 共有248条查询结果,搜索用时 10 毫秒
101.
Topological classification of palmar dermatoglyphics 总被引:2,自引:0,他引:2
102.
Richard E. Spieler Albert H. Meier Harold C. Loesch 《General and comparative endocrinology》1976,29(1):156-160
Plasma concentrations of prolactin were estimated by radioimmunoassay throughout a day at three seasons of the year (summer, fall, and winter) in the striped mullet, Mugil cephalus. Daily rhythms were found at each season. In addition, the patterns of the rhythms with respect to the daily photoperiod differed from one another. The data are consistent with the hypothesis that a seasonal change in the daily rhythm of prolactin has an important role in regulating the seasonal changes in physiology of some animals. 相似文献
103.
Finger ridge count is a valuable quantitative phenotype used in a wide range of biological and anthropological research. However, the scoring of the phenotype is both labour intensive and error prone. This paper describe a freely available software program, RIDGECOUNTER, that can be used to obtain ridge counts from digitized prints (either collected using a digital fingerprint scanner or scanned from an inked print). The program yields semi-automated ridge counts and logs the location of the user-selected core and delta points to aid in the training of new researchers and ensure the repeatability of count. In a validity study of 451 prints, the semi-automated ridge counts of digital prints showed good agreement (r = 0.957) with traditional manual counts of inked-rolled prints (which were obtained 2 years apart and counted by different researchers). In a reliability study of 200 prints, semi-automated ridge counts derived from digital prints collected at two different time points also showed good agreement (r = 0.962) (the prints were obtained 2 years apart and counted by the same researcher). Although designed for use with fingerprints, the program is suitable for use with palm, foot or toe prints using user-defined landmarks. 相似文献
104.
105.
Danuta Z. Loesch 《Clinical genetics》1988,33(3):169-175
Two hundred and eight fragile X subjects (92 males and 116 females) and matched Australian (60 males and 32 females) and British (122 males and 118 females) normal samples were used to calculate 4 discriminant functions, based on dermatoglyphic measurements. The most efficient discriminating variables between fragile X and normal males, selected by means of the Wilk's stepwise method, included: ridge counts on fingers 1-3, the hallucal (f) count on soles, the atd angle, and pattern intensities in palmar areas 2, 4 and 5 as well as on fingers 4 and 5. In females, the ridge breadth, the hallucal (e) count, the atd angle and pattern intensities in palmar areas 3-5 as well as on fingers 1, 3 and 5 comprised the final discriminant. The misclassification rate based on distributions of individual discriminant scores in each pair of samples, and on prior probabilities, was lowest (16.8%) in fragile X males compared with the Australian normal subjects. In both female comparisons, this rate approached 44%. A bias to misclassification rates resulting from various analytical procedures and some properties of the data are discussed. We conclude that the discriminant function based on dermatoglyphic measured variables alone is not good enough for assessing carrier probabilities for fragile X, especially in females. However, we have been able to select the best discriminators which may be used, together with other measured body characteristics, to obtain a more powerful discriminant function. Moreover, a consideration of discriminant scores based on dermatoglyphic traits only may help in estimating carrier probabilities.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
106.
J C Mulley S Yu A K Gedeon A Donnelly G Turner D Loesch C J Chapman R J Gardner R I Richards G R Sutherland 《Journal of medical genetics》1992,29(6):368-374
The utility of the pfxa3 probe for direct molecular diagnosis of the fragile X (FRAXA) has been established. This probe detects amplification of an unstable DNA element consisting of variable length CCG repeats. The size of the amplified fragment is correlated with phenotype and was determined using PstI digested DNA in family members. In 35 families with the fragile X, there was correspondence in 183 cases between the presence of an amplified unstable element and the presence of the fragile X chromosome independently determined by cytogenetics, position in the pedigree, or linked DNA markers flanking the fragile X. There was also correspondence in 124 cases between the presence of the normal 1.0 kb PstI fragment and absence of the fragile X chromosome independently determined by linked flanking markers. Six additional families considered to be isolated cases of 'fragile X' had been diagnosed before recognition of FRAXD. The pfxa3 probe confirmed the cytogenetic diagnosis in three families, the other three being rediagnosed as non-fragile X. A further two families had consistent expression of a different folate sensitive fragile site, FRAXE, close to FRAXA but not associated with fragile X syndrome and not detectable with the pfxa3 probe. Subsequent referrals were received from additional family members or from members of new families for whom carrier status had not been predetermined by linked markers. Direct pfxa3 diagnosis for the 135 females within these 222 additional cases was confirmed by dosage analysis with the control probe pS8.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
107.
108.
110 palms of MZ twins and 111 like-sexed pairs of DZ twins have been compared in respect of a concordance rate of the palmar, sole and finger-tip total pattern types. Dermatoglyphic patterns have been classified according to the topological method, and the distributions of the numbers of discordant pattern elements from homolateral, heterolateral and bilateral comparisons in MZ and DZ twins, respectively, are presented. The highest concordance occurs in homolateral comparisons in MZ twins and the lowest in heterolateral comparisons. Bilateral concordance is highest for sole and finger-patterns, while palmar patterns present a considerable degree of dermatoglyphic asymmetry. Palmar, sole and finger-tip patterns are also not alike in homolateral concordance rates within MZ and DZ twin pairs. The differences between MZ and DZ twins are much more pronounced for sole patterns than for palmar or finger-tip patterns, which is also reflected in the estimated H values. For soles, this may be in some way related to the considerable symmetry of patterns. The fact that some pattern elements are intercorrelated may also introduce a bias in estimates of heritability, based on twin material. 相似文献
109.
Neurohypophysial pituicytes and axons of the rat 48 h after reanimation in connection with experimentally induced clinical death lasting 15 min were examined electron microscopically. In most of pituicytes there appeared ultrastructural alterations indicating a high sensitivity of the cells to the ischaemic conditions associated with clinical death and the postreanimation period. Hyperactive forms of pituicytes rich in subcellular organelles, including lysosomes, as well as hypoactive forms of the cells scarce in organelles but containing numerous electron-lucent vacuoles were seen in the neurohypophysis. Intermediate forms of pituicytes were also perceived. Close appositions of pituicytes and neurosecretory axons (axons enclosed by pituicytes) were frequently observed, and several phases of axon degeneration due to pituicytes were noted. These findings are indicative of an enhanced neuronal-glial interaction in the neurohypophysis during the postreanimation period. Except for degenerated axon profiles enclosed by pituicytes, other altered profiles were occasionally found throughout the neurohypophysis. Thus, in the neurohypophysis unchanged axons predominated rich in neurosecretory granules. Post-embedding PAP-immunolabelling for vasopressin visualised an abundance of vasopressin-positive axon profiles filled with labelled neurosecretory granules. The results of immunocytochemical studies, therefore, suggest a restriction of the release of neurohypophysial hormones in the reanimated rat examined here. At the same time, the results of conventional electron microscopy may indicate an enhanced involvement of pituicytes in the mechanisms regulating the neurohypophysial hormone release. 相似文献
110.
JIAN DZ CHEN ZHIYUE LIN RICHARD W McCALLUM 《Journal of gastroenterology and hepatology》1998,13(Z3):S232-S236
Abstract As in the heart, there is a pacemaker in the human stomach and it generates myoelectrical activity with a frequency of approximately three cycles per minute. Abnormalities in gastric myoelectrical activity may result in gastric motility disorders, such as gastroparesis. Electrical stimulation of the stomach is achieved by delivering electrical currents via electrodes attached to the smooth muscle of the stomach. Recently, a number of studies on electrical stimulation of the stomach in both humans and dogs have indicated that gastric electrical stimulation with appropriate parameters is able to entrain gastric slow waves and normalize gastric dysrhythmias. This has led some investigators to use gastric electrical stimulation to treat patients with gastroparesis. Previous studies and the current state of the field in gastric electrical stimulation in treatment of gastroparesis will be discussed and summarized. 相似文献