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101.
Processing of radical prostatectomy specimens for correlation of data from histopathological, molecular biological, and radiological studies: a new whole organ technique 下载免费PDF全文
Jhavar SG Fisher C Jackson A Reinsberg SA Dennis N Falconer A Dearnaley D Edwards SE Edwards SM Leach MO Cummings C Christmas T Thompson A Woodhouse C Sandhu S Cooper CS Eeles RA 《Journal of clinical pathology》2005,58(5):504-508
AIMS: To develop a method of processing non-formalin fixed prostate specimens removed at radical prostatectomy to obtain fresh tissue for research and for correlating diagnostic and molecular results with preoperative imaging. METHODS/RESULTS: The method involves a prostate slicing apparatus comprising a tissue slicer with a series of juxtaposed planar stainless steel blades linked to a support, and a cradle adapted to grip the tissue sample and receive the blades. The fresh prostate gland is held in the cradle and the blades are moved through the cradle slits to produce multiple 4 mm slices of the gland in a plane perpendicular to its posterior surface. One of the resulting slices is preserved in RNAlater. The areas comprising tumour and normal glands within this preserved slice can be identified by matching it to the haematoxylin and eosin stained sections of the adjacent slices that are formalin fixed and paraffin wax embedded. Intact RNA can be extracted from the identified tumour and normal glands within the RNAlater preserved slice. Preoperative imaging studies are acquired with the angulation of axial images chosen to be similar to the slicing axis, such that stained sections from the formalin fixed, paraffin wax embedded slices match their counterparts on imaging. CONCLUSIONS: A novel method of sampling fresh prostate removed at radical prostatectomy that allows tissue samples to be used both for diagnosis and molecular analysis is described. This method also allows the integration of preoperative imaging data with histopathological and molecular data obtained from the prostate tissue slices. 相似文献
102.
Gansky SA Ellison JA Rudy D Bergert N Letendre MA Nelson L Kavanagh C Walsh MM 《Journal of Athletic Training》2005,40(2):76-87
Context: Athletes in the United States are at high risk for using spit (smokeless) tobacco (ST) and incurring its associated adverse health effects.Objective: To examine whether an athletic trainer-directed ST intervention could decrease initiation and promote cessation of ST use among male collegiate baseball athletes.Design: Stratified, cluster-randomized controlled trial.Setting: Fifty-two California colleges.Patients or Other Participant(s): A total of 883 subjects in 27 intervention colleges and 702 subjects in 25 control colleges participated, as did 48 certified athletic trainers.Intervention(s): For college athletic trainers and associated dental professionals, a 3-hour video conference, and for collegiate athletes, an oral cancer screening with feedback and brief counseling during the preseason health screenings, athletic trainer support for cessation, and a peer-led educational baseball team meeting.Main Outcome Measure(s): The subjects' ST use over 1 year was assessed by self-report. At the end of the study, the certified athletic trainers were mailed a survey assessing their tobacco use and perceptions and behavior related to tobacco control in the athletic environment. We used multivariable logistic regression models for clustered responses (generalized estimating equations) to test the difference between groups in ST-use initiation and cessation and to identify significant overall predictors of noninitiation and cessation of ST use.Results: Of the 1585 athletes recruited, 1248 (78.7%) were followed up at 12 months. In addition, 48 of the 52 athletic trainers (92%) responded to the 1-year follow-up survey. The ST-use initiation (incidence) was 5.1% in intervention colleges and 8.4% in control colleges (generalized estimating equation odds ratio = 0.58, 95% confidence interval = 0.35-0.99). Predictors of ST noninitiation were low lifetime tobacco and monthly alcohol use (odds ratio = 1.98, 95% confidence interval = 1.40- 2.82) and athletic trainers' report that the baseball coach supported ST-use prevention activities (odds ratio = 1.43, 95% confidence interval = 1.11-1.83). Although at 1 year, cessation of ST use was relatively high in both groups (36%), we noted no significant difference between the groups (odd ratio = 0.94, 95% confidence interval = 0.70-1.27).Conclusions: The intervention was significantly effective in preventing incident ST use but did not significantly increase cessation beyond that seen in the control group. The latter finding is inconsistent with previous studies and may be explained by spillover of the intervention to control colleges, other anti-tobacco activity in control colleges, and/or the small sample of dependent ST users enrolled in the study. 相似文献
103.
Adult male sexual behavior in mammals requires the neuronal organizing effects of gonadal steroids during a sensitive perinatal period. During development, estradiol differentiates the rat preoptic area (POA), an essential brain region in the male copulatory circuit. Here we report that increases in prostaglandin-E(2) (PGE(2)), resulting from changes in cyclooxygenase-2 (COX-2) regulation induced by perinatal exposure to estradiol, are necessary and sufficient to organize the crucial neural substrate that mediates male sexual behavior. Briefly preventing prostaglandin synthesis in newborn males with the COX inhibitor indomethacin permanently downregulates markers of dendritic spines in the POA and severely impairs male sexual behavior. Developmental exposure to the COX inhibitor aspirin results in mild impairment of sexual behavior. Conversely, administration of PGE(2) to newborn females masculinizes the POA and leads to male sex behavior in adults, thereby highlighting the pathway of steroid-independent brain masculinization. Our findings show that PGE(2) functions as a downstream effector of estradiol to permanently masculinize the brain. 相似文献
104.
Stenoien DL Cummings CJ Adams HP Mancini MG Patel K DeMartino GN Marcelli M Weigel NL Mancini MA 《Human molecular genetics》1999,8(5):731-741
Spinal bulbar muscular atrophy is a neurodegenerative disorder caused by a polyglutamine expansion in the androgen receptor (AR). We show in transiently transfected HeLa cells that an AR containing 48 glutamines (ARQ48) accumulates in a hormone-dependent manner in both cytoplasmic and nuclear aggregates. Electron microscopy reveals both types of aggregates to have a similar ultrastructure. ARQ48 aggregates sequester mitochondria and steroid receptor coactivator 1 and stain positively for NEDD8, Hsp70, Hsp90 and HDJ-2/HSDJ. Co-expression of HDJ-2/HSDJ significantly represses aggregate formation. ARQ48 aggregates also label with antibodies recognizing the PA700 proteasome caps but not 20S core particles. These results suggest that ARQ48 accumulates due to protein misfolding and a breakdown in proteolytic processing. Furthermore, the homeostatic disturbances associated with aggregate formation may affect normal cell function. 相似文献
105.
Expression of a novel combination of fast and slow troponin T isoforms in rabbit extraocular muscles
Margaret M. Briggs Jean Jacoby Jacob Davidowitz Frederick H. Schachat 《Journal of muscle research and cell motility》1988,9(3):241-247
Summary The properties of extraocular muscles (EOMs) are quite different from those of the trunk and limb. Here we show that there is a novel pattern of troponin T (TnT) expression in EOMs which most likely contributes to the fine control of ocular movement and may reflect their innervation by cranial motoneurons. Three regions of the muscle were analysed to distinguish the TnT isoforms present in the fast singly-innervated fibres from those in the multiply-innervated fibres. More than 95% of the TnT in the singly-innervated fibres is TnT3f, which exhibits the most graded response to changes in calcium concentration during activation (Schachatet al., J. molec. Biol.
198, 551–4). In multiply-innervated fibres, which exhibit tonic contractures, the slow troponin T TnT2s is expressed. While neither TnT3f nor TnT2s is unique to EOM, this pattern is unusual in two respects: first, both TnT3f and TnT2s are minor components of the trunk and limb musculature, and second, most muscles express several fast and both slow TnT species. Although EOM occupies a highly specialized physiological niche, its unusual physiology is not reflected in the presence of new TnT isoforms but in the expression of a different ratio of the known species of TnT. 相似文献
106.
Borrelia burgdorferi and Interleukin-1 Promote the Transendothelial Migration of Monocytes In Vitro by Different Mechanisms 下载免费PDF全文
A prominent feature of Lyme disease is the perivascular accumulation of mononuclear leukocytes. Incubation of human umbilical vein endothelial cells (HUVEC) cultured on amniotic tissue with either interleukin-1 (IL-1) or Borrelia burgdorferi, the spirochetal agent of Lyme disease, increased the rate at which human monocytes migrated across the endothelial monolayers. Very late antigen 4 (VLA-4) and CD11/CD18 integrins mediated migration of monocytes across HUVEC exposed to either B. burgdorferi or IL-1 in similar manners. Neutralizing antibodies to the chemokine monocyte chemoattractant protein 1 (MCP-1) inhibited the migration of monocytes across unstimulated, IL-1-treated, or B. burgdorferi-stimulated HUVEC by 91% ± 3%, 65% ± 2%, or 25% ± 22%, respectively. Stimulation of HUVEC with B. burgdorferi also promoted a 6-fold ± 2-fold increase in the migration of human CD4+ T lymphocytes. Although MCP-1 played only a limited role in the migration of monocytes across B. burgdorferi-treated HUVEC, migration of CD4+ T lymphocytes across HUVEC exposed to spirochetes was highly dependent on this chemokine. The anti-inflammatory cytokine IL-10 reduced both migration of monocytes and endothelial production of MCP-1 in response to B. burgdorferi by approximately 50%, yet IL-10 inhibited neither migration nor secretion of MCP-1 when HUVEC were stimulated with IL-1. Our results suggest that activation of endothelium by B. burgdorferi may contribute to formation of the chronic inflammatory infiltrates associated with Lyme disease. The transendothelial migration of monocytes that is induced by B. burgdorferi is significantly less dependent on MCP-1 than is migration induced by IL-1. Selective inhibition by IL-10 further indicates that B. burgdorferi and IL-1 employ distinct mechanisms to activate endothelial cells. 相似文献
107.
Breast carcinoma diffusely metastatic to the spleen. A report of two cases presenting as idiopathic thrombocytopenic purpura. 总被引:6,自引:0,他引:6
Carcinoma metastatic to the spleen is found at autopsy in 6% to 13% of patients who die of cancer, yet clinical symptoms referable to splenic metastases are unusual. Two cases of breast carcinoma metastatic to the spleen discovered incidentally at therapeutic splenectomy for idiopathic thrombocytopenic purpura are described. On gross examination, the spleens were mildly enlarged with a homogeneous congested cut surface; rare 0.2-cm white nodules were present in one case. Microscopic examination revealed large, poorly cohesive cells that diffusely involved both the red and white pulp. Histochemical, immunohistochemical, and ultrastructural analyses confirmed the epithelial nature of the cellular infiltrate. These cases show that idiopathic thrombocytopenic purpura may herald the presence of diffuse splenic metastases when metastatic disease is not otherwise clinically suspected. The lack of a discrete tumor mass in the spleen in such cases may make the diagnosis of metastatic carcinoma a challenge both clinically and pathologically. Immunohistochemical and electron microscopic examinations are useful to establish the appropriate diagnosis in such cases. 相似文献
108.
Shaw MM Gürr WK Thackray AM Watts PA Littler E Field HJ 《Journal of virological methods》2002,102(1-2):93-102
Levels of bystander death occurring in herpes simplex virus type 1 (HSV-1)-infected mouse brain stems were studied, as well as the extent to which bystander death is influenced by guanosine nucleoside analogue treatment. Consecutive sections from brain stems of HSV-1-infected mice were stained alternately for (i) viral infection and (ii) cell death (TUNEL assay). Virus antigen was detectable in brain stems on day 3 of infection, while TUNEL staining was comparatively lower. An increase in the extent of TUNEL staining was observed on day 4 of infection. Despite this increase, however, the ratio of TUNEL-stained to infection marker-stained tissue still indicated that the amount of TUNEL staining remained lower than infection staining at this time point. On days 5 and 6 of infection, TUNEL staining continued to increase and the TUNEL/infection marker ratio switched on day 6 in favour of excess TUNEL staining, which was observed in and around the foci of infection, suggesting bystander death. The excess TUNEL staining on day 6 of infection was further increased on treatment with antivirals. The significance and implications of these results are discussed with respect to the nature and mechanism of action of the TUNEL assay, dynamics of primary HSV-1 infection, immunological influences and potential effects of antiviral treatment. The potential problems of the TUNEL assay are considered in the context of viral infection and the TUNEL assay, in combination with infection marker staining, may potentially provide a model system for quantitative analysis of true bystander death during HSV infection in vivo. 相似文献
109.
An electron microscopic study of kitten kidney cells infected with a feline calicivirus (a member of the family Picornaviridae) has been carried out. Although cells appeared to be synchronised by the light microscope, electron microscopic changes were extremely variable. The first observable and consistent changes occurred in the nucleus followed by the formation of membrane bound vesicles in the cytoplasm. A variety of arrangements of virus particle accumulation were observed in infected cells. These included crystalline arrays, membranous cisternae and accumulation of particles in fine fibrillar material. The finding of accumulations of virus particles in association with smooth membranes is of importance in respect of the recent biochemical evidence of poliovirus assembly in relation to smooth membranes. 相似文献
110.