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排序方式: 共有557条查询结果,搜索用时 15 毫秒
21.
Jacob Ruiter-Ligeti Michael H. Dahan Naama Steiner Alexander Volodarsky-Perel William Buckett 《Journal of assisted reproduction and genetics》2020,37(12):3103
PurposeThe aim of this study was to determine how female age at the end of the reproductive spectrum effects success of natural cycle intrauterine insemination (IUI) or IUI in combination with ovarian stimulation.MethodsWe performed a retrospective cohort study of women 43 years of age and older at the time of IUI in a single academic fertility center between January 2011 and March 2018. Primary outcomes were both pregnancies and live births per cycle of IUI. Data are presented as percentage or mean ± SD. Fisher exact and chi-squared analyses were performed.ResultsThere were 9334 IUI cycles conducted during the study period. Of these cycles, 325 IUIs (3.5%) were for women aged 43 years and over at the time of insemination (43.6 ± 0.8, range 43 to 47 years). Analysis of these 325 IUI cycles revealed 5 biochemical pregnancies (1.5%) and only 1 live birth (0.3%). The pregnancy rate did not differ between IUIs using donor sperm (N = 1/49, 2.0%) compared to IUIs with partner sperm (N = 4/276, 1.4%). The pregnancy rate did not differ between IUIs with gonadotropins (N = 2/211, 0.9%), clomiphene or letrozole (N = 2/78, 2.6%), or natural cycle (N = 1/36, 2.8%).ConclusionsThe use of intrauterine inseminations in women 43 years of age and older is an ineffective treatment strategy. This is irrespective of the use of ovarian stimulation or donor sperm. Costly gonadotropin injections did not increase the chance of pregnancy nor did oral medication when compared to natural cycle IUIs. 相似文献
22.
White matter structure in autism: preliminary evidence from diffusion tensor imaging. 总被引:38,自引:0,他引:38
Naama Barnea-Goraly Hower Kwon Vinod Menon Stephan Eliez Linda Lotspeich Allan L Reiss 《Neuropsychopharmacology》2004,55(3):323-326
BACKGROUND: Individuals with autism have severe difficulties in social communication and relationships. Prior studies have suggested that abnormal connections between brain regions important for social cognition may contribute to the social deficits seen in autism. METHODS: In this study, we used diffusion tensor imaging to investigate white matter structure in seven male children and adolescents with autism and nine age-, gender-, and IQ-matched control subjects. RESULTS: Reduced fractional anisotropy (FA) values were observed in white matter adjacent to the ventromedial prefrontal cortices and in the anterior cingulate gyri as well as in the temporoparietal junctions. Additional clusters of reduced FA values were seen adjacent to the superior temporal sulcus bilaterally, in the temporal lobes approaching the amygdala bilaterally, in occipitotemporal tracts, and in the corpus callosum. CONCLUSIONS: Disruption of white matter tracts between regions implicated in social functioning may contribute to impaired social cognition in autism. 相似文献
23.
Danny Ben-Zvi Naama Barkai 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(15):6924-6929
Despite substantial size variations, proportions of the developing body plan are maintained with a remarkable precision. Little is known about the mechanisms that ensure this adaptation (scaling) of pattern with size. Most models of patterning by morphogen gradients do not support scaling. In contrast, we show that scaling arises naturally in a general feedback topology, in which the range of the morphogen gradient increases with the abundance of some diffusible molecule, whose production, in turn, is repressed by morphogen signaling. We term this mechanism “expansion–repression” and show that it can function within a wide range of biological scenarios. The expansion-repression scaling mechanism is analogous to an integral-feedback controller, a key concept in engineering that is likely to be instrumental also in maintaining biological homeostasis. 相似文献
24.
Constantini NW Eliakim A Zigel L Yaaron M Falk B 《International journal of sport nutrition and exercise metabolism》2000,10(1):62-70
Much attention has focused on the nutrition and hematological profile of female athletes, especially gymnasts. The few studies on iron status of male adolescent athletes found a low incidence of iron deficiency. The present studies investigated the iron status of male and female gymnasts (G) and compared it with athletes of other sports. Subjects were 68 elite athletes (43 M, 25F) ages 12-18, of four sports: gymnasts (11M,12F), swimmers (11M,6F), tennis players (10M,4F), and table tennis players (11M,3F). All lived in the national center for gifted athletes, trained over 25 hr a week, ate in the same dining room, and shared a similar life style. Mean levels of hemoglobin (Hb), red blood cell indexes, serum ferritin, serum iron, and transferrin were measured in venous blood. There was no difference in mean Rb among gymnasts (G) and nongymnasts (NG). However Hb was less than 14g/dL in 45% of MG vs. only 25% in NG, and less than 13g/dL in 25% of premenarcheal FG vs. 15% in NG. Low transferrin saturation (<20%) was detected in 18% of MG and 25% of FG vs. 6% and 8% in male and female NG, respectively (p<.05). The percentage of males suffering from low ferritin level (<20 ng/ml) was twice as high in G (36%) vs. NG(19%), and about 30% in all females. In summary, iron stores were consistently lower in MG vs. NG. Adolescent athletes of both genders, G in particular, are prone to nonanemic iron deficiency, which might compromise their health and athletic performance. 相似文献
25.
Investigation of white matter structure in velocardiofacial syndrome: a diffusion tensor imaging study 总被引:5,自引:0,他引:5
Barnea-Goraly N Menon V Krasnow B Ko A Reiss A Eliez S 《The American journal of psychiatry》2003,160(10):1863-1869
OBJECTIVE: Velocardiofacial syndrome, caused by a deletion on chromosome 22q11.2, is often accompanied by cognitive, behavioral, and psychiatric impairments. Specifically, velocardiofacial syndrome has been proposed as a disease model for a genetically mediated subtype of schizophrenia. Velocardiofacial syndrome is also known to affect brain structure. The most prominent structural findings in velocardiofacial syndrome are reduced white matter volumes. However, the structure of white matter and extent of specific regional involvement in this syndrome have never been investigated. The current study used diffusion tensor imaging to investigate white matter structure in children and young adults with velocardiofacial syndrome. METHOD: Nineteen participants with velocardiofacial syndrome and 19 age- and gender-matched comparison subjects underwent diffusion-weighted magnetic resonance imaging scans. Whole brain voxel-by-voxel analyses were conducted to investigate white matter fractional anisotropy differences between the groups. RESULTS: Relative to the comparison group, the velocardiofacial syndrome group had reduced white matter anisotropy in the frontal, parietal, and temporal regions as well as in tracts connecting the frontal and temporal lobes. CONCLUSIONS: This study demonstrates that alterations of white matter tract structure occur in velocardiofacial syndrome. Reduced white matter anisotropy was observed in individuals with velocardiofacial syndrome in areas previously implicated in the neurocognitive phenotype of velocardiofacial syndrome. The finding of aberrant parietal white matter tracts as well as aberrant frontotemporal connectivity in velocardiofacial syndrome and in previous schizophrenia studies may be associated with increased vulnerability for development of psychotic symptoms. 相似文献
26.
Friedmann N Biran M 《Cortex; a journal devoted to the study of the nervous system and behavior》2003,39(3):441-463
This study explored access to grammatical gender during naming in Hebrew. Studies of anomia and tip-of-the-tongue states (TOT) found that speakers of various languages (Italian, Spanish, German, Dutch) have information about the grammatical gender of words they fail to retrieve. In Hebrew, on the other hand, a TOT study found that Hebrew speakers could not provide gender information. To test access to gender in single words in Hebrew we used an implicit measure--the analysis of paraphasias of anomic patients with respect to whether or not they preserved the grammatical gender of the target word. The rationale behind this measure was that when a paraphasia is created, it generally conforms to the partial knowledge the speaker has on the target word. If speakers have gender knowledge when they fail to name, they should produce paraphasias that match their partial information, and thus match the gender of the target. Such gender preservation in paraphasias was found in German for individuals with anomia, and in Arabic, French and German for slips of the tongue. Participants were 22 Hebrew-speaking aphasic patients with phonological, semantic or conceptual anomia, who produced 532 paraphasias. None of the participants showed gender preservation in their paraphasias. Even phonological anomics, who have access to semantic information, did not preserve grammatical gender in a single-word naming task. We suggest that this difference between Hebrew and previously studied languages relates to the fact that in Hebrew bare nouns are allowed, and therefore gender is not accessed in single-word naming, whereas in languages in which a noun should be produced as a full NP (with a determiner or case-marking for example) gender has to be accessed even in single-word tasks. We propose a hypothesis according to which gender is accessed if and only if the noun is incorporated into a syntactic tree (or a chunk of a tree) that includes an agreement phrase. 相似文献
27.
28.
Endoscopic third ventriculostomy in patients with cerebrospinal fluid infection and/or hemorrhage 总被引:11,自引:0,他引:11
Siomin V Cinalli G Grotenhuis A Golash A Oi S Kothbauer K Weiner H Roth J Beni-Adani L Pierre-Kahn A Takahashi Y Mallucci C Abbott R Wisoff J Constantini S 《Journal of neurosurgery》2002,97(3):519-524
OBJECT: In this study the authors evaluate the safety, efficacy, and indications for endoscopic third ventriculostomy (ETV) in patients with a history of subarachnoid hemorrhage or intraventricular hemorrhage (IVH) and/or cerebrospinal fluid (CSF) infection. METHODS: The charts of 101 patients from seven international medical centers were retrospectively reviewed; 46 patients had a history of hemorrhage, 42 had a history of CSF infection, and 13 had a history of both disorders. All patients experienced third ventricular hydrocephalus before endoscopy. The success rate for treatment in these three groups was 60.9, 64.3, and 23.1%, respectively. The follow-up period in successfully treated patients ranged from 0.6 to 10 years. Relatively minor complications were observed in 15 patients (14.9%), and there were no deaths. A higher rate of treatment failure was associated with three factors: classification in the combined infection/hemorrhage group, premature birth in the posthemorrhage group, and younger age in the postinfection group. A higher success rate was associated with a history of ventriculoperitoneal (VP) shunt placement before ETV in the posthemorrhage group, even among those who had been born prematurely, who were otherwise more prone to treatment failure. The 13 premature infants who had suffered an IVH and who had undergone VP shunt placement before ETV had a 100% success rate. The procedure was also successful in nine of 10 patients with primary aqueductal stenosis. CONCLUSIONS: Patients with obstructive hydrocephalus and a history of either hemorrhage or infection may be good candidates for ETV, with safety and success rates comparable with those in more general series of patients. Patients who have sustained both hemorrhage and infection are poor candidates for ETV, except in selected cases and as a treatment of last resort. In patients who have previously undergone shunt placement posthemorrhage, ETV is highly successful. It is also highly successful in patients with primary aqueductal stenosis, even in those with a history of hemorrhage or CSF infection. 相似文献
29.
Gothelf D Falk B Singer P Kairi M Phillip M Zigel L Poraz I Frishman S Constantini N Zalsman G Weizman A Apter A 《The American journal of psychiatry》2002,159(6):1055-1057
OBJECTIVE: The authors studied weight gain mechanisms and energy balance in patients treated with olanzapine. METHOD: The body mass index of male schizophrenic adolescent inpatients treated with olanzapine (N=10) and of 10 matched patients treated with haloperidol (N=10) were measured at baseline and after 4 weeks of treatment. For the patients treated with olanzapine, caloric intake, resting energy expenditure, and physical activity (determined through accelerometry and heart rate monitoring) were assessed at baseline and after 4 weeks of treatment. RESULTS: Body mass index significantly increased in those treated with olanzapine but not in those given haloperidol. The increase in body mass index was due to an increase in caloric intake without change in diet composition. Olanzapine had no significant effect on resting energy expenditure. Daily energy expenditure was very low before and after treatment. CONCLUSIONS: Olanzapine-induced weight gain is associated with a general increase in caloric intake. 相似文献
30.
Falk B Portal S Tiktinsky R Weinstein Y Constantini N Martinowitz U 《Medicine and science in sports and exercise》2000,32(1):52-57
PURPOSE: The purpose of this study was to evaluate muscle strength and anaerobic power in young boys with hemophilia compared with healthy boys. METHODS: Thirteen boys with severe hemophilia (H) (mean (+/- SD) age = 12.0 +/- 3.17 yr) and 16 control (C) boys (age = 11.9 +/- 2.8 yr) performed elbow and knee flexion and extension on the Biodex System II dynamometer at two angular velocities. They also performed a Wingate Anaerobic Test (WAnT) for the legs and for the arms. All H subjects received prophylactic factor VIII treatment in the 24 h pretesting, and no test was performed in the presence of hemorrhage. RESULTS: C were consistently stronger than H in all dynamic strength measures (e.g., elbow flexors: 0.47 +/- 0.15 vs 0.36 +/- 0.08 N x m x kg(-1) for C and H, respectively, P < 0.05). Anaerobic mean power was also higher in C compared with H in both upper and lower extremities (arms: 3.08 +/- 0.99 vs 2.22 +/- 0.46 W x kg(-1) for C and H, respectively; legs: 6.94 +/- 1.62 vs 5.54 +/- 1.03 W x kg(-1) for C and H, respectively, P < 0.05). Upper and lower extremity strength, as well as anaerobic power, increased with age in C but not in H. By using the Godin Leisure-Time Exercise Questionnaire, H were found to be much less active, especially in intense activities, compared with C. CONCLUSION: Children and adolescents with hemophilia are characterized by lower muscle strength and anaerobic power compared with age-matched controls. This may be related to their lower leisure-time activity. 相似文献