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121.
This paper reports the occurrence of a rare, yet distinct pituitary adenoma which was surgically removed from a 42-year-old male with both clinical and biochemical evidence of acromegaly and mild hyperprolactinaemia. The monomorphic adenoma consisted of mature cells which were ultrastructurally indistinguishable from those of a prolactinoma. Electron immunocytochemistry, including a series of double-labelling techniques using selected colloidal gold particles as markers, indicated the presence of a pituitary adenoma in which the cells were capable of simultaneously producing growth hormone and prolactin and packaging them within the same secretory granule. This is thought to represent a mammosomatotroph cell adenoma. 相似文献
122.
Herpesvirus saimiri has a gene specifying a homologue of the cellular membrane glycoprotein CD59. 总被引:15,自引:0,他引:15
J C Albrecht J Nicholas K R Cameron C Newman B Fleckenstein R W Honess 《Virology》1992,190(1):527-530
Herpesvirus saimiri (HSV) is a T-lymphotropic tumor virus that causes fulminant lymphomas and leukemias in various New World primates other than its natural host, the squirrel monkey (Saimiri sciureus). In the course of completing the nucleotide sequence of its genome, we identified an open reading frame of 363 nucleotides, designated HVS-15, that has no detectable homology to any other viral sequences to date. HVS-15 encodes a 121-amino-acid protein which shows significant similarities to human CD59, a phosphatidyl-inositol-glycan-anchored glycoprotein involved in T-cell activation and restriction of complement-mediated lysis. The predicted HVS-15 gene product is more similar to human CD59 than to the related murine Ly-6 antigens. A nucleotide sequence identity of 64% was found between HVS-15 and the CD59 reading frame, and a 48% identity exists between the corresponding protein sequences. The comparison of the amino acid sequences revealed a number of conserved structural features such as a similar pattern of hydrophobic termini and an identical cysteine skeleton. 相似文献
123.
Cloning, overexpression, purification, and immunobiology of an 85-kilodalton outer membrane protein from Haemophilus ducreyi 总被引:5,自引:0,他引:5
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Thomas KL Leduc I Olsen B Thomas CE Cameron DW Elkins C 《Infection and immunity》2001,69(7):4438-4446
We have identified an 85-kDa outer membrane protein that is expressed by all tested strains of Haemophilus ducreyi. Studies of related proteins from other pathogenic bacteria, including Haemophilus influenzae, Pasteurella multocida, Neisseria gonorrhoeae, Neisseria meningitidis, and Shigella dysenteriae, suggested a role for these proteins in pathogenesis and immunity. In keeping with the first such described protein from Haemophilus influenzae type B, we termed the H. ducreyi protein D15. The gene encoding the H. ducreyi D15 protein was cloned and sequenced, and the deduced amino acid sequence was found to be most similar to sequences of the D15-related proteins from other Pasteurella spp. The arrangement of the flanking genes was similar to that of H. influenzae Rd and suggested that D15 was part of a multigene operon. Attempts to make a null mutation of the D15 gene were unsuccessful, paralleling results in other D15 gene studies. Overexpression of H. ducreyi D15 in Escherichia coli resulted in a source of recombinant D15 (rD15) from which it was readily purified. rD15 was immunogenic, and it was found that immunization of rabbits with an rD15 vaccine preparation conferred partial protection against a virulent challenge infection. Antisera to an N-terminal peptide recognized all tested strains of H. ducreyi. 相似文献
124.
Obesity is a global public health problem, with about 315 million people worldwide estimated to fall into the WHO-defined obesity categories. Traditional herbal medicines may have some potential in managing obesity. Botanical dietary supplements often contain complex mixtures of phytochemicals that have additive or synergistic interactions. The dried fruit rind of Garcinia cambogia, also known as Malabar tamarind, is a unique source of (-)-hydroxycitric acid (HCA), which exhibits a distinct sour taste and has been safely used for centuries in Southeastern Asia to make meals more filling. Recently it has been demonstrated that HCA-SX or Super Citrimax, a novel derivative of HCA, is safe when taken orally and that HCA-SX is bioavailable in the human plasma as studied by GC-MS. Although HCA-SX has been observed to be conditionally effective in weight management in experimental animals as well as in humans, its mechanism of action remains to be understood. We sought to determine the effects of low-dose oral HCA-SX on the body weight and abdominal fat gene expression profile of Sprague-Dawley rats. We observed that at doses relevant for human consumption dietary HCA-SX significantly contained body weight growth. This response was associated with lowered abdominal fat leptin expression while plasma leptin levels remained unaffected. Repeated high-density microarray analysis of 9960 genes and ESTs present in the fat tissue identified a small set (approximately 1% of all genes screened) of specific genes sensitive to dietary HCA-SX. Other genes, including vital genes transcribing for mitochondrial/nuclear proteins and which are necessary for fundamental support of the tissue, were not affected by HCA-SX. Under the current experimental conditions, HCA-SX proved to be effective in restricting body weight gain in adult rats. Functional characterization of HCA-SX-sensitive genes revealed that upregulation of genes encoding serotonin receptors represent a distinct effect of dietary HCA-SX supplementation. 相似文献
125.
Encephalitis is a rare, but serious complication from vaccination against smallpox using replication competent strains of vaccinia virus. In this report we describe mutants of vaccinia virus, containing N-terminal deletions of the vaccinia virus interferon resistance gene, E3L, that are attenuated for neuropathogenesis in a mouse model system. These recombinant viruses replicated to high titers in the nasal mucosa after intra-nasal infection of C57BL/6 mice but failed to spread to the lungs or brain. These viruses demonstrated reduced pathogenicity after intra-cranial infection as well, indicating a decrease in neurovirulence. Intra-nasal inoculation or inoculation by scarification with a low dose of recombinant virus containing a deletion of the entire N-terminal domain of E3L protected against challenge with a high dose of wild-type vaccinia virus, suggesting that this replication competent, but attenuated strain of vaccinia virus may have promise as an improved vaccine for protecting against smallpox, and as a vector for inducing mucosal immunity to heterologous pathogenic organisms. 相似文献
126.
John A. Morrison Philip R. Khoury Barbara N. Campaigne W. M. Cameron Chumlea Bonny Specker Barbara N. Campaign Shumei S. Guo 《American journal of human biology》1994,6(4):481-490
The purpose of this study was to compare estimates of body composition in two ethnic groups, 31 black and 38 white girls 10 through 16 years of age, to establish accurate and precise laboratory standards for field measures of body composition in the NHLBI Growth and Health Study HC 55025. The dual energy X-ray absorptiometry (DXA) measures of fat free mass (FFM) and % body fat (%BF) were made using Hologic QDR-1000/W. Corresponding values of FFM and %BF from underwater weighing (UWW) were determined using the two-component model of Siri, and these were corrected using the model of Lohman for white girls only. In the comparison of the different models and methods, the two-component model overestimated FFM compared to estimates from DXA for black girls, as did the corrected Lohman model for white girls. The two-component model significantly overestimated %BF in both white and black girls compared to corresponding estimates from DXA. The ratio of bone mineral content (BMC)/FFM affected the degree of %BF differences in black girls but not in white girls. Also, as the density of FFM increased or approached adult status in black girls (BMC/FFM increased), differences between the two-component model and estimates from DXA decreased. In both groups of girls, the relationship of %BF from UWW and DXA are a function of the level of body fatness. DXA values of %BF are greater than those from UWW under about 24% body fat, but the converse occurs above 25% body fat. The inability of UWW using the two-component model to account for the body composition in these girls can be corrected in part by measuring the variables for a multicomponent model or more easily by using DXA estimates of body composition. © 1994 Wiley-Liss, Inc. 相似文献
127.
R. N. Scott R. H. Brittain R. R. Caldwell A. B. Cameron V. A. Dunfield 《Medical & biological engineering & computing》1980,18(1):65-69
Progress in the development of a system to provide sensory feedback of the pinch force of an artificial hand is described.
Design criteria relating to electrocutaneous stimulation and compatibility with myoelectric control are discussed. Details
of a practical system, presently in use by two amputees prior to full-scale clinical evaluation, are presented. 相似文献
128.
129.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
130.
Surgical palliation of unresectable carcinoma of the pancreas 总被引:6,自引:0,他引:6
The results of palliative surgery for pancreatic carcinoma were reviewed in over 10,000 patients from the English-language literature from 1965 to 1983. This collected series suggests that biliary-enteric bypass relieves the sequelae of chronic extrahepatic biliary obstruction, prolongs survival, and provides symptomatic palliation. The more easily constructed loop cholecystojejunostomy is preferred over choledochojejunostomy unless malignant obstruction of the cystic duct is imminent. Chronic percutaneous internal biliary drainage offers reasonable palliation in the poor-risk patient who is not a candidate for surgery. Routine concomitant gastroenterostomy is recommended in all patients with a reasonable life expectancy since operative mortality is unaffected, and the incidence of future duodenal obstruction is at least 16%. Intraoperative chemical splanchnicectomy is easily performed and appears beneficial in relief of pain related to advanced pancreatic carcinoma.
Resumen Se revisaron los resultados de la cirugía paliativa para carcinoma pancreático en más de 10.000 pacientes de la literatura inglesa desde 1965 hasta 1983. Esta serie colectiva sugiere que la derivación bilio-entérica alivia las secuelas de la obstrucción biliar extrahepática crónica, prolonga la supervivencia y provee paliación sintomática. Se prefiere la colecisto-yeyunostomía, que es la de más fácil realización, a menos que la obstrucción neoplásica del canal cístico sea inminente. El drenaje biliar percutáneo crónico ofrece una paliación razonable en el paciente de alto riesgo que no sea candidato para cirugía. Se recomienda la gastroenterostomía concomitante como rutina en todos los pacientes con una razonable expectativa de vida, puesto que la mortalidad operatoria no resulta afectada y la incidencia de futura obstrucción duodenal es de no menos de 16%. La esplacnicectomía química intraoperatoria es fácilmente realizable y es beneficiosa en el alivio del dolor asociado con el carcinoma pancreático avanzado.
Résumé Les résultats de la chirurgie palliative pour cancer du pancréas ont été étudiés dans la littérature anglaise de 1965 à 1983. Ils concernent 10.000 malades et permettent de suggérer que les interventions de dérivation assurent la disparition des symptômes de la rétention biliaire et l'allongement du temps de survie.La simple cholécystojéjunostomie est préférable à la cholédocojéjunostomie dès lors que le canal cystique n'est pas envahi. Le drainage percutané et transhépatique apporte une solution au problème de la rétention biliaire chez le malade en mauvais état général et incapable de subir une intervention chirurgicale. La gastro-entérostomie associée est recommandée chez tous les malades dont l'espoir de vie est de durée raisonnable car la mortalité n'est pas augmentée et le taux d'obstruction duodénale atteint 16%. La splanchnicectomie chimique au cours de l'intervention est facile à pratiquer et permet d'atténuer la douleur en cas de cancer avancé.相似文献