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51.
Pflügers Archiv - European Journal of Physiology - 相似文献
52.
Madeleine R. MacDonald G. Bradley Schaefer Ann Haskins Olney Donna F. Patton 《American journal of medical genetics. Part A》1994,50(1):46-50
Thrombocytopenia with absent radius (TAR) syndrome is infrequently (7%) associated with mental retardation. In those cases, the mental deficiency is presumed to be a consequence of intracranial hemorrhage due to the thrombo-cytopenia. We report on 2 infants with TAR syndrome. One had developmental delay with evidence of cerebral dysgenesis by magnetic resonance imaging (MRI). Such findings have not been noted in the literature, but may not have been investigated in most cases. The other infant with TAR syndrome, who has had normal psychomotor development, has a normal brain on MRI scan. Detailed neuroimaging studies, preferably MRI, should be considered in the evaluation of patients with TAR syndrome, especially when there are documented signs of developmental delay, with or without a history of intracranial hemorrhage. © 1994 Wiley-Liss, Inc. 相似文献
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Clinical magnetic resonance spectroscopy of brain, heart, liver, kidney, and cancer. A quantitative approach 总被引:1,自引:0,他引:1
M W Weiner H Hetherington B Hubesch G Karczmar B Massie A Maudsley D J Meyerhoff D Sappey-Marinier S Schaefer D B Twieg 《NMR in biomedicine》1989,2(5-6):290-297
Clinical studies using 31P and 1H MRS with a whole body 2.0 T MRI/MRS system are described. In most cases, techniques to quantitate absolute molar concentrations of metabolites in various organs were used. In the brain, AIDS, chronic stroke, and white matter lesions were associated with alterations of brain 31P metabolites. Epilepsy was associated with increased pH in the seizure focus. In the heart, dilated cardiomyopathy was associated with increased PDE/ATP while PCr/ATP was unchanged. In the liver, alcoholic hepatitis and cirrhosis were associated with diminished hepatic ATP while alcoholic hepatitis had increased pH and cirrhosis had decreased pH. This allowed differentiation of normal liver, alcoholic hepatitis, and alcoholic cirrhosis without biopsy. In the prostate, malignancy was associated with increased PME/ATP and decreased PCr/ATP. The PME/PCr was greatly increased in malignant prostate with no overlap in normals. Other cancers outside the brain had increased PME and effective treatment was often associated with diminished PME. 1H MRS of the brain was performed using ISIS and outer volume suppression pulses for volume localization. Excellent high resolution 1H water-suppressed spectra were obtained at echo times as short as 30 ms, showing well resolved peaks for lactate, N-acetylaspartate, glutamate, choline, creatinine, and inositol. 1H MRS demonstrated that the uptake of ethanol by the brain was slower than the rise of ethanol in blood. 31P spectroscopic imaging of the brain with resolution of 2.25 x 2.25 x 2.5 cm produced metabolic images and high resolution spectra from desired regions of interest.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
54.
Hans Schaefer 《Pflügers Archiv : European journal of physiology》1936,237(1):717-721
Zusammenfassung Die theoretischen Ursachen des sog. Reizeinbruches bei der Oszillographie von Aktionsströmen mit Verstärkern werden besprochen. Es werden diejenigen Schaltungen angegeben, welche die Verzerrung durch Reizstromeinbruch herabmindern oder aufheben. 相似文献
55.
Yuri A. Zarate Luigi Boccuto Sujata Srikanth Rini Pauly Eylem Ocal Tonya Balmakund Kevin Hinkle Vikki Stefans Gerald B. Schaefer Ronnie Thomas Collins II 《American journal of medical genetics. Part A》2019,179(6):1047-1052
Kosaki overgrowth syndrome is a recently described syndrome characterized by distinctive facial features, brain white matter lesions, and developmental delay. Germline activating heterozygous PDGFRB mutations have been reported in this condition. Systemic connective tissue‐type findings have been described in some individuals. We describe a 19‐year‐old Caucasian female with a history of hydrocephalus, Dandy–Walker malformation, cervical spine arachnoid cyst, progressive scoliosis, and overgrowth. Her physical exam included distinctive craniofacial dysmorphism, as well as soft and hyperextensible skin. Cardiovascular imaging during adolescence revealed saccular aneurysms in both coronary artery systems and subtle tortuosity of the cervical vertebral arteries. Exome sequencing trio analysis identified a de novo previously reported pathogenic variant in PDGFRB, c.1696T>C (p.[Trp566Arg]). Further functional studies included platelet‐derived growth factor cellular metabolic pathway activity that confirmed the variant causes a constitutive activation of the PI3K‐AKT pathway. This is the first report to characterize the activating nature of this PDGFRB variant. We also highlight the connective tissue findings seen in Kosaki overgrowth syndrome and recommend baseline echocardiographic evaluation in all individuals with this condition with particular emphasis on coronary arteries. 相似文献
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57.
Schaefer Jürgen R. von Hirschhausen Eckart 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2021,64(1):21-27
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Menschen mit komplexen und seltenen Erkrankungen haben es in unserem Gesundheitssystem oft schwer. Bis zur Diagnosefindung kann... 相似文献
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59.
The authors have previously described an extradural transmaxillary approach to the anterior compartment of the cavernous sinus. In an effort to expand the surgical access to that area without necessitating a craniotomy or wide transfacial dissection, they present a modification of the transmaxillary approach to the sellar region and cavernous sinus. Methods: The approach was developed on 12 fresh and 12 embalmed cadaveric specimen, and 2 dry skulls. The initial sublabial incision is followed by a maxillotomy to expose the course of the infraorbital nerve (terminal branch of maxillary branch of the trigeminal nerve) on the roof of the maxillary sinus. The route of the infraorbital nerve is traced to the pterygopalatine fossa as a guide to the foramen rotundum. Superomedial drilling of the foramen rotundum is then performed to reveal the contents of the superior orbital fissure. After the nerves are safely identified in the superior orbital fissure, medial enlargement of the window into the cavernous sinus is made possible by drilling the lateral and posterior wall and septum of the sphenoid sinus. Results: The combined transmaxillary transsphenoidal approach offers an excellent exposure of the sellar and infrasellar region. The approach offers clear visualization of the ipsilateral loop of the carotid artery, the pituitary fossa, and the cranial nerves of the ipsilateral cavernous sinus. Mean operative reach is 38 mm from the posterior wall of the maxillary sinus to the ipsilateral carotid loop and 56 mm to the contralateral loop. The width of the operative window is 26 mm at the base within the cavernous sinus. Conclusion: The model offers a minimally invasive approach that avoids the need for craniotomy or violating the nasal cavity. It may be safely employed to access vascular as well as invasive lesions of the sellar and infrasellar region. The approach offers excellent visualization of the ipsilateral intracavernous carotid artery with both proximal and distal control, as well as cranial nerves III, IV, VI, V2, the hypophyseal region, and the medial aspect of the contralateral cavernous sinus. 相似文献
60.
With increasing pressure from third-party payers to assess client outcomes, clinical programs want to know how to implement outcome systems. This article focuses on practical and logistic questions involved in implementing an outcome assessment system in ambulatory behavioral healthcare settings. Study questions addressed outcome systems in general and the use of the Behavior and Symptom Identification Scale (BASIS-32) and the Short Form Health Status Profile (SF-36) in particular. General questions focused on obtaining provider buy-in, client consent and confidentiality, data collection methods, sampling, time points, maximizing client participation, clinical utility of outcome data, and resources needed for outcome assessment. Measure-specific questions focused on client acceptability of the instruments and applicability of measures to diverse populations. The article suggests several strategies for enhancing outcome assessment efforts and concludes that there remains a need for further understanding of ways to maximize the utility and value of outcome measurement. 相似文献