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101.
Many side-effects of red blood cell transfusion have been described. They include iron-overload, as well as allo- and autoantibody formation against red cells. During storage, erythrocytes undergo complex structural and biochemical changes. It has been suggested that accelerated and/or aberrant forms of the physiological erythrocyte aging process underlie the red cell storage lesion. This storage lesion may contribute to side-effects of transfusion as endothelial damage by release of internal erythrocyte constituents, (pro)inflammatory consequences, hampered microcirculation and oxygen delivery. Understanding the process that determines the fate of red blood cells after transfusion may contribute to the prevention of side-effects after red blood cell transfusion. This should be the focus of research on red blood cell transfusion in clinical transfusion medicine. 相似文献
102.
Takaaki Ohmori Kazuyo Okada Ryo Tabei Keisuke Sugiura Shinji Nabeshima Hiroji Ohoka Masaki Okamoto 《Pathology international》1994,44(4):333-337
A case of primary seminal vesicle carcinoma is reported. The tumor was a CA125-producing adenocarcinoma consisting of fine papillary-tubular, intricate branching or anastomosing glandular structures and was composed of small cuboidal, but occasionally hobnailed, cells with mostly clear, but occasionally granular, cytoplasm. Some tumor cells showed evidence of secretion of seromucinous materials into the interpapillary and cystic space. lmmunohistochemically, almost half of the tumor cells expressed a positive reaction with anti-CAl25, a common serological marker for ovarian epithelial carcinomas; however, no tumor cells expressed any other serological tumor markers such as carcinoem-bryonic antigen, α-fetoprotein, human chorionic gonadotropin, prostatic specific acid phosphatase, or prostatic specific antigen. The patient showed a high level of serological CA125, which fluctuated parallel with the growth, removal and recurrence of the tumor. The morphological and immunohistochemical findings suggested a close relationship between the present tumor and clear cell carcinoma of the ovary, which is thought to be of a Müllerian-Wolfian duct origin. 相似文献
103.
Recent advances in human genome research have revealed that genetic polymorphisms, such as single nucleotide polymorphisms (SNPs), are closely associated with susceptibility to various common diseases and adverse drug reactions. Also, numerous mutations responsible for a number of genetic diseases have been identified. Clinical application of genetic information to individual health care requires simple and rapid identification of nucleotide changes in clinical settings. We have devised a novel low-tech method for the detection of a single nucleotide substitution using competitive allele-specific short oligonucleotide hybridization with immunochromatographic strip. The gene of interest is PCR-amplified, hybridized to an allele-specific short oligonucleotide probe in the presence of a competitive oligonucleotide, and subjected to chromatography using a DNA test strip at room temperature. The genotype is unambiguously determined by the presence or the absence of visible purple lines on a strip. Feasibility of the method was demonstrated by the detection of a prevalent disease-causing mutations in glycogen storage disease type Ia (G6PC), medium-chain acyl-CoA dehydrogenase deficiency (ACADM), non-ketotic hyperglycinemia (GLDC), and clinically important polymorphisms in the CYP2C19 gene and the aldehyde dehydrogenase 2 gene (ALDH2). The procedure does not demand either technical expertise or expensive instruments and is readily performed in local clinical laboratories. The result is obtained within 10 min after PCR. This rapid and simple method of SNP detection may be used for point-of-care genetic diagnosis with potentially diverse clinical applications. Hum Mutat 22:166-172, 2003. 相似文献
104.
105.
106.
107.
Mitochondrial DNA polymorphisms in Yunnan nationalities in China 总被引:4,自引:0,他引:4
Nucleotide sequences of the D-loop region of human mitochondrial DNA from four Yunnan nationalities, Dai, Wa, Lahu, and Tibetan,
were analyzed. Based on a comparison of 563-bp sequences in 99 people, 66 different sequence types were observed. Of these,
64 were unique to their respective populations, whereas only 2 types were shared between the Lahu and Wa nationalities. The
D-loop sequence variation and phylogenetic analysis suggested that the 99 mtDNA lineages were classified into eight clusters
in the phylogenetic tree. All lineages that had a 9-bp deletion in the COII/tRNALys intergenic region appeared in one cluster in the D-loop tree, suggesting a single event of the deletion in the Yunnan nationalities
studied. Genetic distances, based on net nucleotide diversities between populations including Han Chinese and mainland Japanese,
revealed that the Dai, Wa, Lahu, and Han Chinese are closely related to each other, while Tibetan and mainland Japanese formed
a single cluster. The bootstrap probabil-ity of separation between the Dai-Wa-Lahu-Chinese clade and the Tibetan-Japanese
clade was 99%, indicating that there are at least two different origins among minority groups in Yunnan province. Although
the genetic distance between Tibetan and Japanese within the clade is rather long, the results may shed light on the origins
of mainland Japanese.
Received: December 22, 2000 / Accepted: January 18, 2001 相似文献
108.
To assess the performance of continuous positive airway pressure devices in treatment of sleep breathing disorders during polysomnographic studies, analysis are based essentially on the patient airflow signal measured by a pneumotachograph and the mask pressure. These signals used either by the softwares or the physicians provide powerful information on respiratory events occurring during the night. However, sometimes signals are artifacted by airflow leaks at the mask or the mouth. These artifacts are causes of information loss and then of possible wrong interpretations. We studied the relationship between airflow and mask pressure at the occurrence of leaks. We used analogy with electrical models and Kirchoff laws to estimate mask leaks and to detect mouth breathing. A Starling model connected to a flow generator simulated respiratory movements. A positive pressure was maintained in the model and artificial leaks comparable to mask leaks were provoked. Then, we replaced the Starling model and the flow generator by two healthy volunteers. We computed mask leaks in both conditions and found no contradiction between the simulated model and the subjects. Equations of the analog circuit were helpful to assess mask leaks and to detect mouth breathing. Such equations could be included in polysomnographs or in pressure generator algorithms either for detecting leaks or adjusting airway pressure. 相似文献
109.
The histopathology of papillary thyroid hyperplasia and papillary thyroid carcinoma is similar enough to cause a diagnostic
dilemma in a few cases. Both lesions may have papillary fronds with fibrovascular cores, nuclear crowding, and nuclear anisocytosis.
Formalin-fixed paraffin-embedded tissues from 30 randomly selected patients with papillary thyroid hyperplasia and an equal
number from patients with papillary thyroid carcinoma were analyzed for expression of cytokeratin 19 (CK19), galectin-3, and
HBME-1. Cases of papillary thyroid carcinoma had moderate to strong CK19, galectin-3, and HBME-1 reactivity although both
CK19 and galectin-3 showed positive staining in a significant number of nonneoplastic thyroid cases. HBME-1 was uncommon in
the nonneoplastic cases. These results indicate that HBME-1 may be useful in helping to distinguish papillary thyroid carcinoma
from hyperplasia in diagnostically difficult cases. 相似文献
110.
Montero R Serrano L Dávila V Segura Y Arrieta A Fuentes R Abad I Valencia L Sierra P Camacho R 《Environmental and molecular mutagenesis》2003,42(3):216-222
Micronuclei and other biomarkers were evaluated in oral cells from 11- to 16-year-old girls living in a foster home in the central area of México City. Variables analyzed for possible association with these biomarkers include smoking habits, body mass index, metabolic polymorphisms for NAT1 and GSTM1 and whether the cells were obtained from the cheek or pharynx. The results indicated that individuals having the NAT1*10 homozygous genotype showed a significant increase in chromatin buds and binucleated cells. When the damage in the cheek was compared with damage in the pharynx, a significant increase in micronuclei and binucleated cells was found for the latter tissue in all the individuals analyzed. 相似文献