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排序方式: 共有671条查询结果,搜索用时 15 毫秒
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E.K. Lavu FRCPA M. Nelson M.Sc PhD H.J. Popp AAIMS BA J. Gibson FRCP FRCPA PhD H. Kronenberg DCP FRCP FRCPA FRCPath H. Pearson FAIMS A. Child FRCOG 《The Australian & New Zealand journal of obstetrics & gynaecology》1997,37(2):180-183
Summary: regnant women who attended antenatal clinics at King George V Hospital, the Birth Centre or were referred by obstetricians from February to July. 1996 were screened for the platelet antigen HPA-la by flow cytometry. Forty out of 2300 (1.7%) were found to be negative for this antigen . Of the 28 women followed throughout their pregnancy, none developed antibody to HPA-la. Platelet counts performed on samples from 17 babies born to 17 of these mothers were all normal. This study proves the simplicity and rapidity of flow cytometry for platelet antigen screening. The results were comparable with the Solid Phase Red Cell Adherence (SPRCA) method and with PCR. The lack of a plentiful supply of specific antibody and the rarity of fetomaternai alloimmune thrombocytopenia (FMAIT) argue against the introduction of routine screening for maternal HPA-la status at the present time. 相似文献
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Rebecca S. Howell-Jones MSc ; Patricia E. Price PhD ; Anthony J. Howard MBBS MSc FRCPath ; David W. Thomas FDRCS MScD PhD 《Wound repair and regeneration》2006,14(4):387-393
The aim of this study was to describe and quantify systemic antibiotic prescribing for patients with chronic skin wounds presenting at the primary care, nonspecialist setting. Data for 1 year were extracted from a general practice morbidity database comprising approximately 185,000 patients attending family medical practitioners in Wales. Patients with chronic wounds (PCW) were identified using Read Codes and compared with nonwound patients who were randomly selected after matching for age-band, sex, and general practice. PCW received a significantly greater number of antibiotic courses than nonwound patients (p<0.001). This increased level of prescribing was evident for flucloxacillin, co-amoxiclav, cefaclor, cefalexin, erythromycin, trimethoprim, metronidazole, and ciprofloxacin (p<0.01 for all). While PCW also had a significantly higher prevalence of diabetes (16.5% compared with 6.6%, p<0.001), and attended at general practice significantly more frequently than nonwound patients (median (interquartile range) of 25 (17-40) visits per year compared with 12 (4-20), p<0.001), importantly, exclusion of diabetic patients and analysis of the proportion of visits on which patients received antibiotics did not affect the significance of the difference in antibiotic consumption. These data show a strong association between occurrence of chronic wounds and prescribing of antibiotics in primary health care, and wide variation in the type and duration of antibiotic therapy for chronic wounds. Further work is now indicated to rationalize this prescribing and determine the role that this exposure to antibiotics plays in the prevalence of antibiotic resistance in this at-risk elderly population. 相似文献
6.
Development of a reconstructed human skin model for angiogenesis 总被引:4,自引:0,他引:4
Parbinder S. Sahota MB ChB MRCS ; J. Lance Burn PhD ; Martin Heaton FRCS MD ; Eric Freedlander FRCS MD ; Simon K. Suvarna FRCPath ; Nicola J. Brown PhD ; Shelia Mac Neil PhD 《Wound repair and regeneration》2003,11(4):275-284
We have previously shown that reconstructed human skin engineered from autologous keratinocytes, fibroblasts, and sterilized donor allodermis stimulates angiogenesis within 5-7 days when placed on well-vascularized wound beds in nude mice. When this reconstructed skin was used clinically in more demanding wound beds, some grafts were lost, possibly due to delayed vascularization. As this reconstructed skin lacks any endothelial cells, our aim in this study was to develop an angiogenic reconstructed skin model in which to explore strategies to improve angiogenesis both in vitro and in vivo. We report that culture of small-vessel human dermal microvascular endothelial cells (HuDMECs) was achieved using magnetic beads coated with an antibody to platelet cell adhesion molecule as a means of purifying the culture. Keratinocytes, fibroblasts, and HuDMECs could be cultured from the same skin biopsy. Initial studies culturing HuDMECs and other sources of endothelial cells with the tissue-engineered skin showed that these cells were capable of slowly entering the dermis under standard culture conditions in vitro. In conclusion, this provides us with a model in which to explore strategies for improving angiogenesis in vitro and also establishes the culture methodologies for the production of reconstructed skin containing autologous keratinocytes, fibroblasts, and endothelial cells. 相似文献
7.
Fiona Campbell MD MRCPath John M Geraghty MBBS MRCPath Mark A.C Appleton MBChB MRCPath E.Dillwyn Williams MD FRCP FRCPath Geraint T Williams MD FRCP FRCPath 《Human pathology》1998,29(12):1531-1535
Colorectal tumorigenesis in familial adenomatous polyposis (FAP) results from somatic mutation of either the normal APC allele or another growth control gene in epithelial cells bearing a germline APC defect. The rate at which tumors develop is therefore dependent on the somatic mutation frequency; it is not known whether this is normal or elevated in FAP. We aimed to quantify stem cell somatic mutation in FAP, comparing it with hereditary nonpolyposis colorectal cancer (HNPCC) and Crohn's disease (CD). Stem cell somatic mutation frequency was studied in 47 FAP patients, 5 HNPCC patients, and 13 CD patients, all younger than 49 years, by quantifying crypt-restricted loss of O-acetyltransferase activity in sections of morphologically normal colonic mucosa from individuals heterozygous for this monogenically inherited polymorphism. Median stem cell somatic mutation frequency was significantly higher in FAP than HNPCC (4.2 × 10−4v 1.4 × 10−4, Mann-Whitney U, P < .02). The level in CD (4.0 × 10−4) was similar to FAR Mutated crypts occurred in groups more frequently in FAP (22%) than HNPCC (12%) or CD (10%), suggesting an increase in stem cell division associated with crypt fission in FAP. We conclude that stem cell somatic mutation frequency is raised in non-neoplastic colorectal mucosa in FAR This is probably related to increased stem cell proliferation and contributes to the high rate of tumor formation in this condition. 相似文献
8.
Inflammatory pseudotumor of lymph node and spleen: An entity biologically distinct from inflammatory myofibroblastic tumor 总被引:6,自引:0,他引:6
Jeffery L. Kutok MD PhD Geraldine S. Pinkus MD David M. Dorfman MD PhD Christopher D. M. Fletcher MD FRCPath 《Human pathology》2001,32(12):1382-1387
Inflammatory pseudotumors (IPTs) of the lymph node and spleen are an uncommon, benign cause of lymphadenopathy and/or splenomegaly that often bear striking clinicopathologic similarities to the inflammatory myofibroblastic tumors (IMTs) found in soft tissues. These tumors have classically been grouped together under the umbrella category of "inflammatory pseudotumor." Recent evidence shows that IMTs are in fact neoplastic processes that often harbor balanced chromosomal translocations involving the ALK kinase gene. These translocations result in expression of ALK kinase in IMTs as assessed by immunohistochemical studies. However, the relationship between IMT and IPT of the lymph node and spleen is uncertain. To determine if ALK tyrosine kinase expression is also present in IPT, 13 cases of IPT (9 involving lymph nodes, 4 splenic lesions) were examined for the presence of ALK tyrosine kinase by immunohistochemical staining on paraffin-embedded tissue. In addition, in situ hybridization studies for Epstein-Barr virus--encoded RNAs (EBER) and immunoperoxidase studies for human herpesvirus-8 (HHV8)--specific proteins were performed. All cases had clinical, morphologic, and immunophenotypic findings typical of IPT and had varying proportions of fibroblastic and inflammatory components. Age ranged from 11 to 75 (median, 40) years; 8 subjects were male, and 5 were female. None of the cases (0 of 13) had positive staining for ALK kinase or HHV8, and in 1 a lymph node (1 of 13) was focally positive for EBV (EBER) by in situ hybridization. The absence of ALK kinase as detected by immunohistochemical studies in IPT of the lymph node and spleen suggests that this entity is biologically distinct from the histologically similar IMT. 相似文献
9.
Optic nerve breast metastasis mimicking meningioma 总被引:1,自引:0,他引:1
O Backhouse BSc FRCOphth I Simmons FRCSOphth FRCOphth A Frank BVSc FRCOphth A Cassels-Brown BSc MD MPH FRCPath MFPHM 《Clinical & experimental ophthalmology》1998,26(3):247-249
Purpose: We report on an optic nerve breast metastasis masquerading initially as a central retinal vein occlusion and later as an optic nerve meningioma. Methods: A 60-year-old female presented with a left central retinal vein occlusion (CRVO). She represented 7 months later with left upper ptosis, proptosis and painful rubeotic glaucoma. Computed tomography (CT) and magnetic resonance imaging suggested an optic nerve meningioma. On referral to the regional orbital unit, a mild left external ophthalmoplegia was noted and, in view of previous right mastectomy and chemotherapy 3 years earlier, the left optic nerve was biopsied simultaneously with left enucleation of her painful eye. Results: Histopathology showed infiltration of the optic nerve and meningeal sheath spreading into the subretinal space and vitreous by malignant epithelial cells, consistent with breast origin. Further CT imaging and bone scans revealed no other metastases. Single field left orbit radiotherapy of 20 Gy was given in five fractions and Arimidex (Zeneca Pharmaceuticals, Cheshire, England) was commenced with the cessation of tamoxifen. The patient was also given an ocular prosthesis. Sadly, she lost vision in her other eye due to retrograde malignant invasion of her optic chiasm and died 6 weeks later. Conclusions: Orbital and choroidal metastases are relatively common but isolated optic nerve metastases are extremely rare. Progressive infiltration of the nerve is likely to enhance CRVO ischaemia and resultant rubeotic glaucoma. In the diagnosis of CRVO, proptosis or external ophthalmoplegia, the presence of pre-existing malignant disease should raise concerns, as delay in diagnosis may affect outcome, particularly if the metastases are sensitive to pharmacological therapy. 相似文献
10.
Luke A. Massey MRCP Caroline Micallef MD FRCR Dominic C. Paviour PhD Sean S. O'Sullivan PhD MRCPI Helen Ling BScMed BMBS MSc David R. Williams PhD Constantinos Kallis PhD Janice L. Holton PhD FRCPath Tamas Revesz MD FRCPath David J. Burn MD FRCP Tarek Yousry Dr med Habil FRCR Andrew J. Lees MD FRCP Nick C. Fox PhD FRCP Hans R. Jäger MD FRCR 《Movement disorders》2012,27(14):1754-1762
Conventional magnetic resonance imaging (cMRI) is often used to aid the diagnosis of progressive supranuclear palsy (PSP) and multiple system atrophy (MSA), but its ability to predict the histopathological diagnosis has not been systematically studied. cMRI from 48 neuropathologically confirmed cases, including PSP (n = 22), MSA (n = 13), Parkinson's disease (PD) (n = 7), and corticobasal degeneration (n = 6), and controls (n = 9) were assessed blinded to clinical details and systematically rated for reported abnormalities. Clinical diagnosis and macroscopic postmortem findings were retrospectively assessed. Radiological assessment of MRI was correct in 16 of 22 (72.7%) PSP cases and 10 of 13 (76.9%) MSA cases with substantial interrater agreement (Cohen's kappa 0.708; P < .001); no PSP case was misclassified as MSA or vice versa. MRI was less sensitive but more specific than clinical diagnosis in PSP and both more sensitive and specific than clinical diagnosis in MSA. The “hummingbird” and “morning glory” signs were highly specific for PSP, and “the middle cerebellar peduncle sign” and “hot cross bun” for MSA, but sensitivity was lower (up to 68.4%) and characteristic findings may not be present even at autopsy. cMRI, clinical diagnosis, and macroscopic examination at postmortem have similar sensitivity and specificity in predicting a neuropathological diagnosis. We have validated specific radiological signs in pathologically confirmed PSP and MSA. However, the low sensitivity of these and macroscopic findings at autopsy suggest a need for imaging techniques sensitive to microstructural abnormalities without regional atrophy. © 2012 Movement Disorder Society 相似文献