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1.
D P Derman D Ballot T H Bothwell B J MacFarlane R D Baynes A P MacPhail M Gillooly J E Bothwell W R Bezwoda F Mayet 《The British journal of nutrition》1987,57(3):345-353
The absorption of iron from soya-bean (Glycine hispida)-based and milk-based infant formulas was assessed in 138 multiparous Indian women, using the erythrocyte utilization of radioactive Fe method. Fe absorption was significantly greater from the basal milk formula (1.5 g protein) than it was from the basal soya-bean formula (2.3 g protein), with geometric mean values of 0.083 and 0.044 respectively. Ascorbic acid markedly increased Fe absorption from the milk-based formula in a dose-dependent fashion. The increase was fivefold when the ascorbic acid:Fe ratio on a weight-for-weight basis was 6:1 and over tenfold when it was 20:1. In contrast, ascorbic acid had a less-marked effect on the absorption of Fe from the soya-bean-based formula, with only a two- to threefold increase at an ascorbic acid:Fe ratio of 20:1. The geometric mean Fe absorption from the soya-bean formula (1.27 mg Fe, 2.3 g isolated soya-bean protein (ISP] was somewhat less than that from the same amounts of ISP and ascorbic acid made up in milk (0.075 and 0.113 respectively). However, a direct comparison between the soya-bean formula in milk and in water showed no significant difference (0.043 and 0.060 respectively). Fe absorption from a drink containing 10 g ISP and 30 mg ascorbic acid was significantly better than that from a similar drink containing the soya-bean flour from which ISP is extracted (0.044 and 0.027 respectively). Heating ISP to 200 degrees for 2 h before its use had no effect on Fe availability.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
2.
GP SCHWAB AL BLUM E BODNER B DALLEMAGNE K GLASER H KOOP F PACE W RÖSCH JR SIEWERT G WETSCHER 《Journal of gastroenterology and hepatology》1997,12(12):785-789
Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper. 相似文献
3.
4.
Missense FGFR3 mutations create cysteine residues in thanatophoric dwarfism type I (TD1) 总被引:10,自引:1,他引:10
Rousseau F; el Ghouzzi V; Delezoide AL; Legeai-Mallet L; Le Merrer M; Munnich A; Bonaventure J 《Human molecular genetics》1996,5(4):509-512
Thanatophoric dwarfism (TD) is a sporadic lethal skeletal dysplasia with
micromelic shortening of the limbs, macrocephaly, platyspondyly and reduced
thoracic cavity. In the most common subtype (TD1), femurs are curved, while
in TD2, straight femurs are associated with cloverleaf skull. Mutations in
the fibroblast growth factor receptor 3 (FGFR3) gene were identified in
both subtypes. While TD2 was accounted for by a single recurrent mutation
in the tyrosine kinase 2 domain, TD1 resulted from either stop codon
mutations or missense mutations in the extracellular domain of the gene.
Here, we report the identification of FGFR3 mutations in 25/26 TD cases.
Two novel missense mutations (Y373C and G370C) were detected in 8/26 and
1/26 TD1 cases respectively. Both mutations created cysteine residues in
the juxta extramembrane domain of the receptor. Sixteen cases carried the
previously reported R248C (9/26 cases), S249C (2/26 cases) or stop codon
FGFR3 mutations (5/26 cases). Our results suggest that TD1 is a genetically
homogeneous condition and give additional support to the view that newly
created cysteine residues in the extracellular domain of the protein play a
key role in the severity of the disease.
相似文献
5.
6.
Identification of the multiple endocrine neoplasia type 1 (MEN1) gene. The European Consortium on MEN1 总被引:10,自引:0,他引:10
Lemmens I; Van de Ven WJ; Kas K; Zhang CX; Giraud S; Wautot V; Buisson N; De Witte K; Salandre J; Lenoir G; Pugeat M; Calender A; Parente F; Quincey D; Gaudray P; De Wit MJ; Lips CJ; Hoppener JW; Khodaei S; Grant AL; Weber G; Kytola S; Teh BT; Farnebo F; Thakker RV 《Human molecular genetics》1997,6(7):1177-1183
7.
Yang GC; Croaker D; Zhang AL; Manglick P; Cartmill T; Cass D 《Human molecular genetics》1998,7(6):1047-1052
Lethal white foal syndrome (LWFS) is a congenital anomaly of horses
characterized by a white coat colour and aganglionosis of the bowel, which
is similar to Hirschsprung disease (HSCR). We decided to investigate
possible mutations of the endothelin-B receptor gene ( EDNRB ) in LWFS as
recent studies in mutant rodents and some patients have demonstrated EDNRB
defects. First, we identified a full-length cDNA for horse EDNRB . This
cDNA fragment contained a 1329 bp open reading frame which encoded 443
amino acid residues. The predicted amino acid sequence was 89, 91 and 85%
identical to human, bovine and mouse as well as rat EDNRB respectively, but
only 55% identical to the human, bovine and rat endothelin A receptor
(EDNRA). Secondly, sequence analysis, together with allele-specific PCR and
the amplification- created restriction site (ACRS) technique, revealed a
dinucleotide TC-- >AG mutation, which changed isoleucine to lysine in
the predicted first transmembrane domain of the EDNRB protein. This was
associated with LWFS when homozygous and with the overo phenotype when
heterozygous.
相似文献
8.
R D Baynes H Flax T H Bothwell W R Bezwoda P Atkinson B Mendelow 《American journal of clinical pathology》1986,85(2):226-229
A study was done to explore the claim that anisocytosis as measured by the red blood cell volume distribution width (RDW) is raised in iron-deficiency anemia, but is normal in the anemia of chronic disorders. Measurements were done on 283 normal patients, 22 iron-deficient patients, and 102 tuberculotic patients, using a model S plus Coulter Electronic Counter with standard calibration. Mean (+/- SD) values for RDW were as follows: normals, 7.36 (+/- 0.57); untreated iron deficiency, 10.39 (+/- 1.37); and 15 untreated anemic patients with tuberculosis, 10.44 (+/- 0.63). Mean values remained above 10.4 in 69 patients with tuberculosis during treatment, irrespective of whether or not the patients were anemic, but had fallen towards the normal mean (8.49 +/- 0.8) in the 18 subjects in whom it was measured at the end of therapy. By this time the mean corpuscular volume (MCV) and hemoglobin concentrations had risen to normal. It is concluded that RDW values in the chronic inflammatory disorder tuberculosis are not significantly different from those occurring in iron-deficiency anemia. 相似文献
9.
A monoclonal antibody against nerve growth factor receptor. Immunohistochemical analysis of normal and neoplastic human tissue 总被引:5,自引:0,他引:5
S J Thompson G C Schatteman A M Gown M Bothwell 《American journal of clinical pathology》1989,92(4):415-423
The expression of human nerve growth factor (NGF) receptor in tumors and normal tissue was investigated with the use of a monoclonal antibody recently developed against that protein. This antibody, NGFR5, reacted strongly with 100% of 25 nerve sheath tumors. Eight of nine pheochromocytomas and three of three paragangliomas also had positive results, but the immunoreactivity was restricted to the sustentacular cell population. Within cells of melanocytic lineage, there was no immunostaining of melanocytes in normal epidermis, whereas 13 of 14 benign nevi had positive results, primarily involving spindled nevocytic structures within the dermis. NGF receptor was scarcely expressed in human melanoma; 9 of 19 melanomas had positive results, but immunoreactivity was generally restricted to rare cells within the larger tumor cell population. Among nonneurogenic mesenchymal tumors, results were generally negative: 0 of 5 chondrosarcomas, 0 of 6 malignant fibrous histiocytomas, 0 of 3 meningiomas, and 1 of 8 leiomyosarcomas were immunoreactive. Carcinomas were variable in immunoreactivity: 12 of 16 squamous cell carcinomas had positive results, whereas adenocarcinomas demonstrated focal, basal epithelial immunoreactivity and neuroendocrine tumors generally had negative results. Among normal tissues, in addition to expected neural immunostaining, NGFR 5 reacted positively with several nonneural cell types, including lymphoidal follicular dendritic cells, myoepithelial cells, vascular adventitia, and basal epithelium of oral mucosa and hair follicles. Antibodies to NGF receptor may play a role in the identification of benign and malignant soft tissue lesions. 相似文献
10.
Nonhereditary p53 mutations in T-cell acute lymphoblastic leukemia are associated with the relapse phase 总被引:2,自引:0,他引:2
We have previously reported that greater than 60% of human leukemic T- cell lines possess mutations in the p53 tumor suppressor gene. To determine whether T-cell acute lymphoblastic leukemia (T-ALL) patient samples possess p53 mutations, we screened peripheral blood-and bone marrow-derived leukemia samples, taken at diagnosis and at relapse, for p53 mutations. Exons 4 through 9 and selected intron regions of the p53 gene were analyzed using polymerase chain reaction-single-strand conformation polymorphism and direct sequencing. p53 mutations were found in 0 of 15 T-ALL diagnosis samples, as compared with 10 of 36 (28%) T-ALL relapse samples. To determine whether p53 mutations play a role in the recurrence (relapse) of T-ALL, two special groups of T-ALL patients were studied: (1) a group of 8 relapse patients whose disease was refractory to chemotherapeutic treatment, and (2) a group of 6 "paired" T-ALL cell samples from patients for whom we possess both diagnosis and relapse samples. Three of 8 relapsed patients (37.5%) whose disease was refractory to the reinduction of remission by chemotherapy possessed missense mutations of the p53 gene. All 3 cases had mutations in exon 5. Among the paired samples, 3 of 6 patients harbored p53 mutations at disease recurrence, but possessed only wild- type p53 alleles at diagnosis. One case had mutation on exon 4, 1 case in exon 5, and 1 case in exon 8 with loss of heterozygosity. These data clearly indicate that recurrence of T-ALL is associated with missense mutations in p53. Our results indicate that (1) mutations of p53 do occur in T-ALL in vivo, and such mutations are associated with the relapse phase of the disease; and (2) p53 mutation is involved in the progression of T-ALL. This conclusion is supported by our observation that the introduction of T-ALL-derived mutant p53 expression constructs into T-ALL cell lines further increases their growth rate in culture, enhances cell cloning in methylcellulose, and increases tumor formation in nude mice. 相似文献