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31.
Pancreatic pseudotumor in pancreas divisum: CT characteristics 总被引:1,自引:0,他引:1
P M Silverman L McVay R K Zeman B S Garra E G Grant M H Jaffe 《Journal of computer assisted tomography》1989,13(1):140-141
We report a case in which a focally spared area of pancreatic tissue in a gland otherwise replaced by fat created a "pseudomass" mimicking neoplasm on sonography and CT. The "pseudomass" appearance was related to the anomalous ductal anatomy in pancreas divisum. The spared area of pancreas creating a "pseudomass" was drained by the dorsal duct and the remainder of the pancreas that had undergone relative fatty replacement was drained by the ventral duct. 相似文献
32.
Occlusion and the solution to the aperture problem for motion 总被引:5,自引:0,他引:5
The "aperture problem" indicates that a local reading of the velocity of an oriented contour is inherently ambiguous, insufficient by itself to recover the velocity of image points. In Wallach's "barber pole" display consisting of moving diagonal lines within an elongated rectangular aperture, it has been suggested that the unambiguous motion of edge-terminators along the longer edges of the aperture propagates towards the motion-ambiguous center part of drifting stripes. This results in the perception of a surface moving in the direction of the longer axis of the aperture. By manipulating the stereoscopic disparity of a striped pattern relative to the aperture plane, we found that the disambiguating effects of terminators could be abolished if the striped pattern was in uncrossed disparity relative to the aperture plane. Also, the motion in 3 separate horizontally oriented, and vertically aligned apertures which would otherwise be seen as moving horizontally, was seen as "linked" together and moving vertically. This occurred only when the horizontally oriented segments separating these apertures were stereoscopically coded so that they appeared as occluders in front. These findings suggest that accidental or "extrinsic" terminators created by occluding edges are treated differently from real or "intrinsic" terminators, and that the real-world constraint of occlusion is thus implemented in the ambiguity-solving processes for motion. 相似文献
33.
The clinical history and histological features of seven cases of granulomatous mastitis are presented. The lesion occurs in young parous women as a tender extra-areolar breast lump. Histologically, non-caseating discrete granulomas are present, confined to breast lobules with, in three cases, coalescence of the granulomas and microabscess formation. Pathogenesis of the changes is discussed. It is thought that granulomatous mastitis is an entity morphologically distinct from duct ectasia/plasma cell mastitis and the commoner forms of granulomatous breast diseases. 相似文献
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Joseph. H. Lee Maruit Chulikavit Deborah Pang Warren B. Zigman Wayne Silverman Nicole Schupf 《Neuroscience letters》2007
Recent reports have suggested that variants in the sortilin-related receptor gene (SORL1) increase the risk of late onset Alzheimer's disease (AD) in Northern European, Hispanic, African–American and Isreali–Arab populations. SORL1 directs trafficking of amyloid precursor protein (APP) and under-expression of SORL1 may lead to over-expression of β amyloid peptides. Adults with Down syndrome (DS) over-express APP and have early onset and high risk for AD. We investigated the relation of seven variants in the gene for SORL1 to age at onset and risk for AD among 208 adults with DS, 45–70 years of age at baseline. Participants were ascertained through the New York State developmental disability service system and followed at 18-month intervals. Information from cognitive assessments, caregiver interviews, medical record review and neurological examination was used to establish the diagnosis of dementia. Homozygosity for the minor T allele in rs556349 and for the minor C allele in rs536360 was associated with later age at onset and reduced risk of AD (HR = 0.26, 95% CI: 0.08–0.86; and HR = 0.40, 95% CI: 0.16–0.98, respectively). Mean age at onset was approximately four years later in individuals who were homozygous for those alleles compared with those who had at least one major allele. These findings indicate a modest association of variants in SORL1 with AD. In addition, we did not observe the same alleles to be associated with AD compared with earlier studies, suggesting that these SNPs are in linkage disequilibrium (LD) with the putative functional variants or that expression of the SORL1 gene and hence its interaction with APP might be modified by the extremely high levels of APP characteristic of Down syndrome. Thus, further studies are needed to identify functional variants that influence risk for AD in this uniquely vulnerable population. 相似文献
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Fine-needle aspiration biopsy of 50 adrenal masses from 48 patients was performed between 1984 and 1991. The series consisted of 28 males and 20 females, with an age range of 12 months to 79 years (mean age, 55 years). Clinical and/or pathologic follow-up was available in 37 patients. Fine-needle aspiration was diagnostic in all 29 malignant cases having follow-up, with no false-positive diagnoses. There were six primary malignancies (three neuroblastomas, two pheochromocytomas, and one adrenal cortical carcinoma) and 23 metastatic lesions. Of these, the lung was the most frequent primary malignancy (60%), followed by melanoma and renal cell carcinoma (8.6% each). The remaining nonmalignant fine-needle aspiration diagnoses were adrenal cortical neoplasms (most likely adenoma), adrenal cortical hyperplasia, myelolipoma, benign adrenal tissue, and abscess. Based on clinical follow-up, three other adrenal adenomas were not diagnosed by fine-needle aspiration. Six biopsy specimens (12%) were insufficient for diagnosis. Ancillary studies including electron microscopy and/or immunocytochemistry were performed on 13 malignant aspirates and provided additional confirmation of the cytology diagnosis in 12 cases. This study confirms that fine-needle aspiration is a sensitive and highly specific procedure for the evaluation of primary and metastatic malignancies involving the adrenal gland. The technique is less useful in the workup of benign processes but, in some instances, can provide specific diagnostic information. 相似文献
39.
Autoantibody response to the Ro/La particle may predict outcome in neonatal lupus erythematosus. 总被引:3,自引:0,他引:3 下载免费PDF全文
E D Silverman J Buyon R M Laxer R Hamilton P Bini J L Chu K B Elkon 《Clinical and experimental immunology》1995,100(3):499-505
This study was undertaken to determine the role of antibodies against both recombinant Ro (r-Ro) and La (r-La) proteins and polypeptides derived from the recombinant La protein in predicting fetal and neonatal outcome in children at risk to develop neonatal lupus erythematosus (NLE). All sera were obtained in the perinatal period and quantitative ELISA assays were used. We collected 41 maternal sera within 2 months of delivery of a child with NLE (21 with congenital heart disease block (CHB) and 20 with dermatologic NLE) and 19 sera from anti-Ro and/or anti-La antibody-positive mothers with systemic lupus erythematosus (SLE) who delivered a child without NLE. All sera were tested for anti-r-La and anti-r-Ro antibodies by ELISA, and most sera were tested for antibodies directed against La polypeptides by immunoblot. We found significantly higher anti-r-La antibody levels in the sera from mothers of children with NLE compared with sera from mothers of unaffected children (0.67 +/- 0.43 versus 0.14 +/- 0.30; P < 0.0001). There was a statistically significant difference in the mean anti-r-La levels between the sera of mothers of children with CHB compared with dermatologic NLE (0.51 +/- 0.45 versus 0.83 +/- 0.37 respectively; P = 0.0091). When we examined antibodies directed against the recombinant 52-kD Ro protein, there was a statistically significant elevation of titres in the sera of mothers of NLE children (0.77 +/- 0.35) compared with non-NLE mothers (0.29 +/- 0.39; P < 0.0001). There was no difference in the r-Ro levels between mothers of children with dermatologic NLE compared with CHB (0.82 +/- 0.37 versus 0.71 +/- 0.74; P = 0.32). When we examined polypeptides derived from the recombinant La protein, the mean number of polypeptides recognized by sera from mothers of children with NLE was significantly higher than the mean number of polypeptides recognized by sera from mothers of unaffected children (5.1 +/- 0.54 versus 2.3 +/- 0.54 respectively; P < 0.001). More importantly, when we examined the individual polypeptides, we found that only sera from mothers of children with NLE and not from mothers of unaffected children recognized a polypeptide designated DD (30% versus 0%, respectively). These studies indicate that the autoantibody response to the Ro/La particle can differentiate sera from mothers of children with NLE and sera from mothers of unaffected children. Furthermore, there was a difference in the anti-La autoantibody response between mothers of children with CHB and dermatologic NLE.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
40.
A. J. Silverman 《Developmental dynamics》1975,144(4):445-459
The development of the hypothalamic magnocellular neurosecretory system of the fetal guinea pig was examined by immunohistochemistry. Neurophysin was first observed in the supraoptic nucleus (SON), median eminence (ME) and posterior pituitary (PP) on day 40 of gestation. It was not regularly present in the paraventricular nucleus (PVN) until day 47. Vasopressin was first observed in the SON, ME and PP on day 45. In the median eminence immunoreactive deposits indicative of both peptides were observed in both the fibers of the hypothalamo-hypophysial tract (H-HT) in the presumptive zona interna as well as in axons projecting to the developing primary portal plexus. 相似文献