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991.
Martin Griebe Michael Daffertshofer Mark Stroick Magdalena Syren Parviz Ahmad-Nejad Michael Neumaier Juergen Backhaus Michael G. Hennerici Marc Fatar 《Neuroscience letters》2007
Biological markers play an evolving role in the diagnosis of Alzheimer disease (AD). We compare conventional measurements of cerebrospinal fluid (CSF) tau and β-amyloid1–42 proteins to a novel approach – Fourier transformed infrared (FT-IR) spectroscopy – a simple technique derived from chemical and physical sciences that characterizes intramolecular bonds. For automatic diagnostic analysis, we developed an artificial neural network (ANN). We examined 71 patients with a clinical diagnosis of AD and 66 controls. β-Amyloid1–42 was decreased (sensitivity 80% and specificity 78%); tau was elevated (sensitivity 76% and specificity 88%) in CSF of AD patients. The combined tau/β-amyloid1–42 quotient was able to distinguish healthy from diseased subjects with 99% sensitivity and 86% specificity. The ANN could separate FT-IR spectroscopy data with 88.5% sensitivity and 80% specificity. FT-IR spectroscopy proved to be cost-effective and simple to perform. Diagnostic sensitivity and specificity is in the range of CSF tau and β-amyloid1–42 protein analysis. Larger sample numbers for ANN training and validation could increase diagnostic accuracy and thus prove to be a useful screening tool. 相似文献
992.
993.
994.
Autopsies were performed in 40 cases of nonimmune hydrops fetalis during the period from 1975 to 1983. In 25 cases specific anatomic diagnoses, including hematologic disorders, infections, chromosomal abnormalities, congenital anomalies, and tumors, were made. In the majority the diagnosis of hydrops fetalis was made prenatally by ultrasonography. The mean gestational age at delivery was 30 weeks; 23 infants were stillborn, and 17 died during the neonatal period. Body weights were consistently increased; peripheral edema and ascites were present in all cases and pleural effusions in all but two cases. Hepatosplenomegaly, cardiomegaly, and pulmonary hypoplasia were frequent findings. The most consistent microscopic changes involved endocrine organs. Islet cell hyperplasia and Leydig cell hyperplasia were common, and thyroid hyperplasia was found occasionally. The fetal zone of the adrenal cortex was often thick and composed of swollen, vacuolated cells. Enhanced extramedullary erythropoiesis was observed in all cases. Thirty-nine placentas were examined; 34 were edematous (mean weight, 547 g), with villous edema, excess erythroblastemia and normoblastemia, and occasional intravillous hematopoiesis. Nonimmune hydrops fetalis has a range of known causes. Thorough autopsy, including placental examination, is the most useful approach for determining the etiology. In 23 cases the probable or possible cause was established in this manner. Antibody studies should also be performed in all cases to exclude an immunologic etiology. Synthesis of clinical, serologic, and pathologic data offers prospects for rational management and prediction of recurrence. 相似文献
995.
Monoclonal antibody LICR -LON- M18 identifies the immunodominant oligosaccharide sequence of the I(Ma) blood-group antigen: Gal beta 1----4GlcNAc beta 1----6--. In primary breast cancers this structure is almost totally cryptic, due to "masking" by sialic acid, but can be revealed by digestion with the specific glycosidase neuraminidase. Following desialylation, light microscopic immunohistochemical examination has revealed the epitope identified by LICR -LON- M18 to be heterogeneously distributed throughout the population of breast carcinoma cells. These tumor cells express the antigen as both a cytoplasmic and a surface membrane determinant. In the normal human breast, this structure is expressed exclusively along the luminal plasma membranes of the duct and alveolar littoral epithelial cells. Desialylation of tissue sections of normal resting and lactating breast epithelium with neuraminidase virtually abolishes the heterogeneous intercellular distribution of the I(Ma) determinant. In desialylated nonneoplastic breast tissues, the expression of this antigen is observed within the cytoplasm of some myoepithelial cells, but not in the littoral epithelial cells. The expression of the I(Ma) antigen by neoplastic and normal breast epithelial cells has also been compared with that of the oligosaccharide sequence Gal beta 1----3GalNAc. This structure, recognized by peanut agglutinin, forms the dominant portion of the Thomsen-Friedenreich antigen. With respect to normal and lactating breast epithelial cells, both oligosaccharide structures are sialylated and appear to be similarly misprocessed by breast carcinomas. The masking of surface carbohydrate determinants and the faulty processing of structures usually expressed on the surface of non-neoplastic breast epithelial cells may be important phenomena in the pathobiology of breast carcinomas. 相似文献
996.
Birgitta Swolin Aleksander Weinfeld Johan Waldenström Jan Westin 《Cancer Genetics and Cytogenetics》1983,9(3):197-209
Of 33 consecutive patients with chronic myelocytic leukemia, examined during metamorphosis, 82% showed chromosome abnormalities in addition to the Ph1. Aberrations most frequently encountered were +8 (39%), +22q - (30%), and i(17q) (18%). Translocations other than the Ph1 were observed in four cases and - Y clones in four cases. Discrepancies in the cytogenetic pattern between bone marrow and extramedullary tissues or blood were noted in a total of 15 patients. In six cases, transformation occurred in extramedullary organs at a time when it was not present in the marrow. In three cases the bone marrow transformation was preceded by a lymph node blastic infiltrate; in one case, by a skin infiltrate; and in one case, by a subdural blastoma. Clonal abnormalities additional to the Ph1 were identified in the tumor tissue from all these cases. Patients with primary extramedullary transformation tended to have a lower median age at onset of metamorphosis, shorter survival, and higher incidence of chromosome abnormalities than the cases without extramedullary involvement. Patients with only Ph1-positive cells and no other anomalies had a slightly longer duration of metamorphosis and longer total survival. Basophilia and thrombocytopenia were more marked in cases with i(17q) than in the rest of the series. 相似文献
997.
Unilateral obstruction of a duplicate uterus is very rare. The current recommendation for its correction involves transmural incision of the uterine muscle. A method is presented here that was successfully applied in one patient suffering from this anomaly, using sonographically guided hysteroscopy. This method obviated the need for an extensive operation. 相似文献
998.
Keld Kjeldsen Aage Nørgaard Torben Clausen 《Pflügers Archiv : European journal of physiology》1985,404(4):365-373
The relationship between the number of3H-ouabain binding sites and the Na, K-pump mediated K-uptake has been characterized in rat soleus muscle. By brief exposure to3H-ouabain (1×10–6–1×10–5mol/l) in vitro, it could be measured that 19–94% of the ouabain binding sites had been occupied. This was associated with a proportionate decrease in the ouabain suppressible K-uptake indicating that under strictly standardized conditions, measurements of3H-ouabain binding sites quantify functional Na,K-pumps.When 3 week old rats were K-depleted for a further week followed by K-repletion 2 h before measurements, the3H-ouabain binding site concentration was 61% lower than in age-matched control soleus muscles. However, the ouabain suppressible K-uptake was only reduced by 35% partly because intracellular Na remained higher in the muscles obtained from K-depleted rats.From the 1st to the 4th week of life, the3H-ouabain binding site concentration increased 2.9-fold. In contrast, the ouabain suppressible K-uptake decreased by a factor 3.5. Accordingly, in muscles from 1 week old rats, the ouabain suppressible K-uptake per3H-ouabain binding site was 10-fold higher than in muscles from 4 week old rats. This difference could not be accounted for by changes in intracellular Na, total or extracellular water. It may be related to differentiation and change in structure.On the basis of the present results and those reported in the literature for mouse and frog skeletal muscle it was calculated that under resting conditions at 30°C in vitro, isolated skeletal muscles only utilize between 3 and 25% of their total capacity for active Na, K-transport. Therefore, variations in the total Na, K-pump capacity may not readily be detected in measurements of the ouabain suppressible rate of K-uptake. 相似文献
999.
Bruce G. Bender Mary H. Puck James A. Salbenblatt Arthur Robinson 《Clinical genetics》1984,25(5):435-445
Four infants identified through neonatal screening programs are an unselected sample of 47,XYY boys. No consistent physical stigmata or medical disorders were identified. Three have increased height. All four demonstrated problems in motor and language development. Although their intelligence is within the average range, all four have language-related learning disorders requiring special education. Mild depression was apparent in all four, perhaps as a secondary result of their learning disorders. Some of the problems seen in the propositi are found in milder forms in other family members, leading to the hypothesis that their karyotype may heighten vulnerability to pre-existing familial conditions. Similarities between these findings and results from seven other study centers with a total of 42 47,XYY boys are noted. Parents of a prenatally diagnosed 47,XYY fetus seen in our center are informed that the extra Y chromosome represents a risk factor for these problems, but that environment remains a primary force in shaping their child's development. 相似文献
1000.
The morphology of Merkel cells in sinus hair follicles of the upper lip (vibrissae with a circular blood sinus), and in touch domes of the glabrous skin of the nose, was investigated in cats up to 12 weeks after resection of the infraorbital nerve. Even 12 weeks after denervation there was neither an ultrastructural alteration of Merkel cells nor a reduction of their number in sinus hair follicles. Also in touch domes the Merkel cells did not disappear. 相似文献