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排序方式: 共有10000条查询结果,搜索用时 531 毫秒
31.
Hagit Cohen Joseph Zohar Michael A Matar Zeev Kaplan Amir B Geva 《Neuropsychopharmacology》2005,58(8):640-650
BACKGROUND: Unsupervised fuzzy clustering (UFC) analysis is a mathematical technique that groups together objects in the multidimensional feature space according to a specified similarity measurement, thereby yielding clusters of similar data points that can be represented by a set of prototypes or centroids. METHODS: Since clinical studies of mental disorders distinguish between affected and unaffected individuals, we designed an inclusion/exclusion criteria (cutoff behavioral criteria [CBC]) approach for animal behavioral studies. The effect of classifying the study population into clearly affected versus clearly unaffected individuals according to behaviors on two behavioral paradigms was statistically significant. RESULTS: Here the raw data from previous studies were subjected to UFC algorithms as a means of objectively testing the validity of the concept of the CBC for our experimental model. The first UFC algorithm yielded two clearly discrete clusters, found to consist almost exclusively of the exposed animals in the one and unexposed animals in the other. The second algorithm yielded three clusters corresponding to animals designated as clearly affected, partially affected, and clearly unaffected. The algorithm for physiological data in addition to behavioral data failed to elicit discrete clusters. CONCLUSIONS: The UFC analysis yielded data that support the conceptual contention of the CBC and lends additional validity to our previous behavioral studies. 相似文献
32.
33.
Ali S. Ziaee Nadia Khatibzadeh Alireza Rahimnia Ahmad S. Mousavi Shaban Mehrvarz 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2005,15(4):270-274
The aim of this study is to identify the effect of time and pressure of tourniquet in blood pressure and pulse rate immediately after the releasing of tourniquet in the upper and lower extremity of the orthopedic surgeries. This retrospective study examined 206 consecutive patients. Comparisons of the systolic and diastolic pressure and heart rate were made before the induction of anesthesia and tourniquet inflation, and immediately after the deflation. In general, there was no significant difference in hemodynamic changes between the upper- and lower-limb with regard to the type of anesthesia. There was no significant correlation between systolic blood pressure and tourniquet pressure, while by increasing the tourniquet time significantly, the systolic blood pressure decreases immediately after the deflation. Interestingly, the considerable increase in age paralleled with a significant decrease in the systolic blood pressure. The effect of tourniquet time is more than the age. There was no significant correlation between the tourniquet pressure and tourniquet time with diastolic blood pressure. Simply the increase in age significantly paralleled with the mild decrease in diastolic blood pressure Orthopedic surgeons are recommended not to rely on the benefits of tourniquet to raise blood pressure due to hypotensive conditions after the deflation especially in the old. 相似文献
34.
G. Amir S. Silberman Z. Neeman R. Udassin D. Seror E. Rosenmann 《Pediatric surgery international》1991,6(4-5):353-356
A 7 1/2-year-old girl with an inflammatory pseudotumor of the lung is presented. The nature of the lesion was not recognized pre-or intraoperatively. The lesion was rubbery, yellowish, and well-defined but not encapsulated. Histologically, a spindle-cell lesion with a storiform pattern and chronic inflammatory-cell infiltrate was seen. The immunological and ultrastructural studies supported an inflammatory origin. The lesion corresponds to the fibrous histiocytoma variant of inflammatory pseudotumor of the lung, as defined recently by Matsubara et al. [17]. This must be distinguished from rare benign neoplasms of the lung such as benign fibrous histiocytoma, leiomyoma, Schwannoma, and histiocytosis. 相似文献
35.
PURPOSE: Two studies are presented here. Study 1 was aimed at evaluating whether the voice characteristics of women who use birth control pills that contain different progestins differ from the voice characteristics of a control group. Study 2 presents a meta-analysis that combined the results of Study 1 with those from 3 recent studies that compared voices of women who use and do not use birth control pills. METHOD: In Study 1, voice samples from 30 women with no history of voice training, who use pills with different progestins (drospirenone, desogestrel, gestodene), and 10 women who do not use the pill were recorded at specific time points across the menstrual cycle and were analyzed acoustically. In Study 2, results from Study 1 were analyzed jointly with results from three recent studies, which used similar methodologies. RESULTS: Results of Study 1 did not reveal acoustic differences in sustained phonation of vowels across the pill groups and controls. Results of the meta-analysis performed in Study 2 indicated that pill users exhibited lower jitter and shimmer values on sustained vowels, whereas no difference of fundamental frequency was observed among women who use the pill. CONCLUSIONS: These results support findings from previous studies, which suggested that no adverse effect on voice was detected among nonprofessional speakers who use new-generation monophasic birth control pills, for the measures studied. Furthermore, results of the meta-analysis suggested that some acoustic properties of the voice, which are reflected in perturbation measures in sustained vowels, may be improved among women who use the pill. 相似文献
36.
The aim of this study was to determine whether there are quantitative changes in the innervation of the anterior cruciate ligament in osteoarthritis. Eleven whole anterior cruciate ligaments were obtained at autopsy from cadavera of individuals with advanced osteoarthritis; five healthy ligaments were used as controls. The ligaments were transected and stained with hematoxylin and eosin, oil red O for fat, and a modification of Gairn's gold chloride method. The latter stain permits visualization of axons, mechanoreceptors, and free nerve endings that are not apparent on routine stains. The ratio of nerve tissue to periligamentous synovial tissue was determined histomorphometrically by the point-counting method. The nerve tissue was located almost exclusively in the periligamentous synovial tissue. There was a statistically significantly greater area of nerve tissue (as a percentage of the total area) around the anterior cruciate ligaments in the osteoarthritic group than around the ligaments in the control group (p < 0.02). The nerve tissue was distributed evenly throughout the periligamentous synovial tissue in the specimens in both groups. A neurological role has been proposed for the anterior cruciate ligament in osteoarthritis. This study provides morphological evidence for neural pathology of the anterior cruciate ligament in subjects with osteoarthritis. 相似文献
37.
STUDY OBJECTIVES: We conducted the present study to determine whether psychiatric disorders are commonly associated with sleep apnea in Veterans Health Administration beneficiaries. METHOD: The Veterans Health Administration maintains several centralized databases containing healthcare data for more than 4 million veterans. We reviewed data from 1998 to 2001 and identified patient records having International Classification of Diseases-Ninth Edition-Clinical Modification codes indicating sleep apnea and various psychiatric conditions. Subsequently, we compared age, sex, ethnicity, and prevalence of comorbid psychiatric conditions for Veterans Health Administration beneficiaries with and without sleep apnea. RESULTS: Out of 4,060,504 unique cases, 118,105 were identified as having sleep apnea (estimated prevalence of 2.91%). Mean age at the time of diagnosis was 57.6 years. Psychiatric comorbid diagnoses in the sleep apnea group included depression (21.8%), anxiety (16.7%), posttraumatic stress disorder (11.9%), psychosis (5.1), and bipolar disorders (3.3%). Compared with patients not diagnosed with sleep apnea, a significantly greater prevalence (P < .0001) was found for mood disorders, anxiety, posttraumatic stress disorder, psychosis, and dementia in patients with sleep apnea. CONCLUSIONS: Sleep apnea is associated with a higher prevalence of psychiatric comorbid conditions in Veterans Health Administration beneficiaries. This association suggests that patients with psychiatric disorders and coincident symptoms suggesting sleep-disordered breathing should be evaluated for sleep apnea. 相似文献
38.
N-cadherin expression in adrenal tumors: upregulation in malignant pheochromocytoma and downregulation in adrenocortical carcinoma 总被引:2,自引:0,他引:2
Cell adhesion molecules (CAMs) are important regulators of tumor growth. The aim of the present study was to evaluate the
expression pattern of CAMs in adrenal tumors regarding origin (cortex vs medulla) and biologic behavior (benign vs malignant).
Eighty-seven adrenal tumors were investigated by immunocytochemistry (ICC) using monoclonal antibodies against N-cadherin
(NCAD), E-cadherin (ECAD), neural cell adhesion molecule (NCAM), and CD44. Western blotting was performed on 30 tumors using
the same antibodies. Markers for proliferation (Ki-67) and catecholamine synthesis (tyrosine hydroxylase) were also analyzed
in tumors by ICC. NCAD was expressed in 12/27 benign pheochromocytomas (BPCs) (12 familial cases), 8/8 malignant pheochromocytomas
(MPCs), 28/30 adrenocortical adenomas, and 9/22 adrenocortical carcinomas. ECAD was expressed in 0/27 BPCs, 0/8 MPCs, 0/30
adrenocortical adenomas, and 2/22 adrenocortical carcinomas. NCAM was expressed in 26/27 BPCs, 7/8 MPCs, 21/30 adrenocrotical
adenomas, and 17/22 adrenocortical carcinomas. CD44 was expressed in 23/27 BPCs, 6/8 MPCs, 7/30 adrenocortical adenomas, and
4/22 adrenocortical carcinomas. Both cortical and medullary adrenal tumors expressed NCAD, NCAM, and CD44 but were devoid
of ECAD. The expression of CD44 and NCAM did not correlate with the malignant potential of tumors. NCAD was upregulated in
MPCs, but downregulated in adrenocortical carcinoma. Thus, NCAD appears to be involved in the development of both cortical
and medullary adrenal tumors. 相似文献
39.
Distal Proctocolitis and n-3 Polyunsaturated Fatty Acids (n-3 PUFAs): The Mucosal Effect In Situ 总被引:1,自引:0,他引:1
Almallah YZ Ewen SW El-Tahir A Mowat NA Brunt PW Sinclair TS Heys SD Eremin O 《Journal of clinical immunology》2000,20(1):68-76
It has been postulated that patients with ulcerative colitis (UC) have altered reactivity of gut-associated lymphoid tissue. In such cases there is intense infiltration of the mucosa with immune competent cells and associated tissue damage. We have shown previously that the dietary supplementation with the n-3 polyunsaturated fatty acids (n-3 PUFAs), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) results in significant systemic immune suppression. The aim of this study, therefore, was to evaluate the in situ effect of n-3 PUFAs on distal proctocolitis. Each patient received either fish oil extract (EPA 3.2 g, DHA 2.4 g) (n = 9) or sunflower oil (n = 9) daily in a double blind manner for six months. Monthly assessment included: (1) disease activity using clinical, sigmoidoscopic, and histological scores and (2) immunohistochemical analysis (immunoglobulins, CD profiles) of rectal biopsy specimens (before and after six months supplementation) using monoclonal antibodies and quantitative computer-assisted video image analysis. Prior to receiving supplementation, patients with proctocolitis (n = 18) showed significantly higher numbers of cells expressing CD3 (pan T cells) and HLA-DR and IgM containing cells compared with non-colitic controls (n = 8). Six months supplementation with n-3 PUFAs resulted in significant reduction in the number of cells expressing CD3 and HLA and the percentage of cells containing IgM. There was no significant change in the CD20 nor the percentage of IgG or IgA containing cells in either group of patients with procto-colitis. In patients receiving n-3 PUFA supplementation, there was improvement in the disease activity and histological scores, compared with pretreatment evaluation. This study has demonstrated both evidence of suppression of in situ immune reactivity and concurrent reduction in disease activity in patients with proctocolitis receiving n-3 PUFA supplementation. This may have important implication for therapy in patients with ulcerative colitis. 相似文献
40.
Mohagheghi AA Moraes R Patla AE 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2004,155(4):459-468
One of the goals of this study was to examine the nature and role of distant visual information sampled during locomotion in the feedforward control of leading and trailing limb while an individual is required to step over an obstacle in the travel path. In addition we were interested in whether or not on-line visual information available while the limb (lead or trail) is stepping over the obstacle influences limb trajectory control and whether the information provided during lead limb cross would be used to calibrate movement of the trail limb. Towards this end, we manipulated availability of vision following an initial dynamic sampling period during the approach phase in proximity to the obstacle and during the lead and trail limb stepping over the obstacle. Ten participants completed 40 trials of obstacle crossing in 8 testing conditions. Initial dynamic visual sampling was sufficient to ensure successful task performance in the absence of vision in the approach phase and during both lead and trail limb stepping over the obstacle. Despite successful task performance, foot placement of the lead and trail limb before obstacle crossing and limb elevation over the obstacle were increased after withdrawal of vision in the approach area. Furthermore, the correlation between toe clearance and foot placement was diminished. While both limbs require feedforward visual information to control the step over the obstacle, only lead limb elevation was influenced by availability of on-line visual information during obstacle crossing. Results were in agreement with the notion of primacy of information inherent in the optic array over those from static samples of the environment in guiding locomotion. It is suggested that the expected proprioceptive feedback information associated with the limb posture before the obstacle, reconstructed using visual memory from dynamic sampling of the environment, mismatched with those from the actual limb position. Accordingly, participants adopted a different strategy that enabled them to clear the obstacle with a higher safety margin.Financial assistance was provided by a grant from the Office of Naval Research, USA, NSERC/Canada, and CAPES/Brazil. We would like to thank Milad G. Ishac, Mike Greig, Zinat Shafaei-Shirazi, and Candida T. Goncalves for their assistance 相似文献