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101.
Tyrone B. Hayes 《Environmental health perspectives》2006,114(9):A518-A519
102.
Donald R Murphy 《The spine journal》2006,6(4):459-463
BACKGROUND CONTEXT: Spinal manipulation applied to the cervical spine is a relatively safe and effective treatment for neck pain and headache. However, complications of this form of treatment have been reported and these can at times be disabling and on rare occasions can be devastating. A postmanipulation complication being treated with a different form of manipulation has not previously been reported. PURPOSE: To report a case of a patient who was treated with manipulation and who developed neck, scapular, and arm pain and arm numbness after the sixth visit, which was later attributed to three herniated discs. The patient was subsequently treated with a nonsurgical approach that included, but was not limited to, a different form of manipulation with apparent resolution of the problem. STUDY DESIGN/SETTING: The patient was a 38-year-old banker who began seeing a chiropractic physician for treatment that included cervical manipulation. On the sixth visit, he developed pain immediately after treatment which became severe and was accompanied by numbness in his arm. He saw a neurosurgeon who recommended surgery, but was subsequently seen by a different chiropractic physician and was treated nonsurgically. METHODS: The patient was found to have clinical signs of radiculopathy, including motor loss. Magnetic resonance imaging revealed disc herniations at C3-C4, C4-C5, and C5-C6. RESULTS: The patient was treated by the author with an alternate approach that included non-high-velocity, low-amplitude manipulation and exercise with resolution of the problem. CONCLUSION: This paper reports a case of a patient with radiculopathy secondary to multilevel disc herniations that appeared to be precipitated by cervical manipulation and who was treated nonsurgically with resolution of the problem. It is doubtful that the manipulation actually caused the disc herniations, but it is possible that it caused preexisting asymptomatic disc herniations to become symptomatic. Consideration should be given to nonsurgical referral of patients who have postmanipulative complications but do not need immediate surgery. 相似文献
103.
Heroin use is postulated to act as a cofactor in the neuropathogenesis of human immunodeficiency virus (HIV-1) infection. Astrocytes, integral components of the CNS, are reported to be susceptible to HIV-1 infection. Upon activation, astrocytes release a number of immunoregulatory products or modulate the expression of a number of proteins that foster the immunopathogenesis of HIV-1 infection. However, the role of heroin on HIV-1 infectivity and the expression of the proteome of normal human astrocytes (NHA) have not been elucidated. We hypothesize that heroin modulates the expression of a number of proteins by NHA that foster the neuoropathogenesis of HIV-1 infection. We utilized LTR amplification and the p24 antigen assay to quantitate the effect of heroin on HIV-1 infectivity while difference gel electrophoresis (DIGE) combined with protein identification through high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to analyze the effects of heroin on the proteomic profile of NHA. Results demonstrate that heroin potentiates HIV-1 replication in NHA. Furthermore, heroin significantly increased protein expression levels for protein kinase C (PKC), reticulocalbin 1 precursor, reticulocalbin 1, tyrosine 3-monooxgenase/tryptophan 5-monooxgenase activation protein, chloride intracellular channel 1, cathepsin D preproprotein, galectin 1 and myosin light chain alkali. Heroin also significantly decreased protein expression for proliferating cell nuclear antigen, proteasome beta 6 subunit, tropomyosin 3, laminin receptor 1, tubulin alpha 6, vimentin, EF hand domain family member D2, Tumor protein D54 (hD54), ATP synthase, H+ transporting, mitochondrial F1 complex and ribosomal protein S14. Identification of unique, heroin-induced proteins may help to develop novel markers for diagnostic, preventative and therapeutic targeting in heroin using subjects. 相似文献
104.
The flawed basis for FDA post-marketing safety decisions: the example of anti-depressants and children. 总被引:2,自引:0,他引:2
Donald F Klein 《Neuropsychopharmacology》2006,31(4):689-699
105.
106.
107.
Donald B. White Cynthia A. Walawander Dong Y. Liu Thaddeus H. Grasela 《Journal of pharmacokinetics and pharmacodynamics》1992,20(3):295-313
In a simulation study of inference on population pharmacokinetic parameters, two methods of performing tests of hypotheses comparing two populations using NONMEM were evaluated. These two methods are the test based upon 95% confidence intervals and the likelihood ratio test. Data were simulated according to a monoexponential model and, in that context, power curves for each test were generated for (i)the ratio of mean clearance and (ii)the ratio of the population standard deviations of clearance. To generate the power curves, a range of these parameters was employed; other pharmacokinetic parameters were selected to reflect the variability typically present in a Phase II clinical trial. For tests comparing the means, the confidence interval tests had approximately the same power as the likelihood ratio tests and were consistently more faithful to the nominal level of significance. For comparison of the standard deviations, and when the volume of information available was relatively small, however, the likelihood ratio test was more able to detect differences between the two groups. These results were then compared to results on parameter estimation in order to gain insight into the question of power. As an example, the nonnormality of estimates of the ratio of standard deviations plays an important role in explaining the low power for the confidence interval tests. We conclude that, except for the situation of modeling standard deviations with only sparse information, NONMEM produces tests of significance that are effective at detecting clinically significant differences between two populations.Partial support from the Upjohn Company, NIH-BRSG SO RR 07066, and the Burroughs Wellcome Foundation. 相似文献
108.
Raouf A. Mikhail Donald N. Reed David B. Bybee Matthias I. Okoye Max E. Dodds 《Head & neck》1988,10(6):427-431
A unique case of a malignant oncocytoma of the maxillary sinus is reviewed in detail. The ultrastructural findings are presented. The histologic and ultrastructural criteria that characterize onco-cytes and the clinicopathologic features of benign and malignant oncocytomas are discussed. This case represents the eleventh reported case that would truly qualify as a malignant oncocytoma of the paranasal sinuses. 相似文献
109.
The Changing Faces of the Nutcracker Esophagus 总被引:3,自引:0,他引:3
Christine B. Dalton P.A.C. Donald O. Castell M.D. Joel E. Richter M.D. 《The American journal of gastroenterology》1988,83(6):623-628
Although the nutcracker esophagus, characterized by high amplitude peristaltic contractions with mean distal amplitude greater than 180 mm Hg, is the most common esophageal motility disorder associated with noncardiac chest pain, little is known about its natural history. Therefore, we reviewed the manometric tracings of 23 patients with the nutcracker esophagus who had an average of 4.6 studies during a mean period of 32 months. Ten age-matched volunteers with normal baseline manometry who had undergone multiple studies (mean 5.8) over a mean time span of 32 months served as controls. In the 17 nutcracker patients with three or more motility studies, the variability of mean distal amplitudes between studies was 41.9% +/- 4.1 (+/- SE) compared to 27.0% +/- 3.3 for the control subjects (p less than 0.01). Highest distal pressures were noted during the first study in 11 of 17 patients (65%) compared to two of 10 controls (20%). The consistency of the diagnosis of nutcracker esophagus varied considerably: four patients always had high amplitude pressures, three patients only had the nutcracker diagnosis on the initial study, and 10 patients intermittently had pressures in the nutcracker range. Overall, these 17 patients had the diagnosis of the nutcracker esophagus confirmed on only 54% of subsequent studies. Changes in motility patterns were intermittently seen in six of 23 patients: one diffuse spasm and five nonspecific motility disorders. None of the control subjects developed high amplitude contractions or changed their motility pattern on serial testing. The possible pathophysiological implications of the changing faces of the nutcracker esophagus are discussed. 相似文献
110.
Regina F. Gandour-Edwards Paul J. Donald Philip J. Vogt Robert Munn Kyung-Whan Min 《Head & neck》1994,16(4):379-382
Background. Carcinosarcoma or true malignant mixed tumor of the parotid gland is extremely rare, accounting for <1% of all salivary gland malignancies. Methods. A 63-year-old woman presented with a 5-cm right parotid mass which was resected with a radical parotidectomy and infratemporal fossa dissection. Results. The tumor contained two distinctive histologic patterns, that of a poorly differentiated ductal carcinoma and a pleomorphic rhabdomyosarcoma. Additionally, a residual focus of pleomorphic adenoma was present peripherally, Immunohistochemical and electron microscopic studies confirmed the skeletal muscle differentiation. Conclusions. The pattern of combined rhabdomyosarcoma and ductal carcinoma has not been previously reported and adds further evidence to the myoepithelial derivation of these tumors. © 1994 John Wiley & Sons, Inc. 相似文献