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1.
This overview describes our preliminary experience in the application of transvaginal color Doppler sonography in evaluation of the uterus and ovaries. The main indications for this type of sonography include evaluation for ovarian torsion, differentiation of benign from malignant ovarian masses, diagnosis of pelvic congestion, and assessment of utero-ovarian perfusion. Obstetric applications include evaluation of complicated early pregnancy and evaluation of placental disorders such as placenta accreta. No doubt future applications will arise soon from active investigation with this new technique.  相似文献   
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The movement of surface mounted targets (SMT) on a shell at the mid-shank and of bone mounted targets attached to the distal shank using a Percutaneous Skeletal Tracker (PST) were simultaneously measured during free-speed walking of three adult subjects having different body types. Surface movement errors in shank kinematic estimates were determined by expressing the segmental motion derived from the SMT relative to the PST-based segment coordinate system (SCS) located at the segment center of gravity. The greatest errors were along and around the shank longitudinal axis, with peak magnitudes of 10 mm of translation and 8° of rotation in one subject. Estimates of knee joint center locations differed by less than 11 mm in each SCS direction. Differences in estimates of net knee joint forces and moments were most prominent during stance phase, with magnitudes up to 39 N in the shank mediolateral direction and 9 N.m about the mediolateral axis. The differences in kinetics were primarily related to the effect of segment position and orientation on the expression of joint forces and on the magnitude and expression of joint moments.  相似文献   
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Thirty healthy HIV negative volunteers were randomised to receive 200 micrograms of rgp120W61D in either: 3D-MPL and QS21, with an oil and water emulsion (SBAS-2) (13); or 3D-MPL and QS21 (SBAS-1) (11); or alum (six). Immunizations were given at 0, 4 and 28 weeks and 23 (77%) participants completed the schedule. Adverse events were more frequent (P < 0.001) and more severe (P < 0.001) in the SBAS-2 group. Binding antibodies to the homologous rgp120W61D were detected after the first immunisation only in those receiving SBAS-1 and SBAS-2, were maximal after the third immunization in all three groups, and persisted to week 84 only in the novel adjuvant groups. These differences were significant (p = 0.02). Neutralising antibodies to TCLA-strains of HIV-1 were observed after the second immunization in all three groups, were maximal after the third immunization, but did not neutralise homologous or heterologous PBMC derived primary HIV-1 isolates. Proliferative T-cell responses to rgp120W61D were maximal after the second immunization and reached very high values in the SBAS-2 group. HIV-1 specific CD8+ MHC Class I restricted cytotoxic T-lymphocytes were not seen in a subset of participants tested at a single timepoint. SBAS-2 with rgp120W61D induced antibody titres as high as those seen in HIV infection, but the quality of the antibodies remained different in that there was no evidence of primary isolate neutralisation. Although cell-mediated immunity was enhanced by SBAS-2 in terms of lymphoproliferative responses, HIV-1 specific CD8+ cytotoxicity was not demonstrated.  相似文献   
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Although exposure of LLC-PK1 epithelial cell sheets to phorbol esters (TPA) causes a near immediate and total decrease of transepithelial electrical resistance (TER), continuation of exposure for 3 to 4 days results in a tachyphylactic response as TER begins to return to control levels. Recovery of TER is maximal by 5 to 6 days, but reaches only 70 to 80% of control level. A reciprocal change in the transepithelial flux of D-mannitol indicates that the TER decrease is indicative of an increase in tight junction permeability. Exposure of cell sheets to TPA for several days also results in the appearance of multilayered polyp- like foci (PLFs) across the otherwise one cell layer thick cell sheets. The pattern of penetration of the electron dense dye, ruthenium red, from the apical surface, across the tight junction and into the lateral intercellular space indicates that the tight junctions of the cell sheet become uniformly leaky after acute exposure to TPA. However, when exposure is continued for several days, only the junctions of cells in the PLFs manifest leakiness. The decrease in TER following acute TPA exposure correlates with the translocation of protein kinase C-alpha (PKC alpha) into a membrane-associated compartment. With exposure of several days, only a trace of PKC alpha is visible by Western immunoblot, and this is in the membrane-associated compartment. Immunofluorescent microscopy indicates that the trace of PKC alpha seen in the Western immunoblots is ascribable distinctly to cells of the PLFs. Monolayer areas between PLFs show no discernible immunofluorescent signal. The data therefore indicate that tight junction barrier function may be restored in certain areas by the down regulation of PKC alpha from the membrane-associated compartment. Failure to down regulate may result in the paracellular leakiness and abnormal cell architecture of the PLFs. Possible implications of this model for in vivo epithelial tumor promotion are discussed.   相似文献   
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BACKGROUND: We hypothesized that total skin-sparing mastectomy (TSM) including where the skin overlying the nipple and areola is preserved would be oncologically safe and facilitate improved cosmetic reconstruction. METHODS: A review (May 2003 through January 2005) was completed on all procedures that were performed through an inframammary incision or a previous scar with reconstruction using Botox, AlloDerm, and a subpectoral tissue implant. RESULTS: Thirty-one patients had 50 TSMs. Twelve percent (6/50) of TSMs had the skin of the nipple and areola resected: 4 (14% of tumors) because of tumor involvement and 2 (4%) because of skin necrosis. Fourteen percent of patients had other complications: 4% (2/50) had infection and/or flap necrosis and 10% (5/50) had superficial epidermolysis requiring no intervention, for a total complication rate of 18%. Average cosmetic score was 8.5 (range 4 to 10). No recurrences are evident after mean follow-up of 7.9 +/- 5.4 months. CONCLUSION: Our short-term experience suggests that TSM has an acceptable complication rate, is theoretically oncologically safe, and facilitates an improved cosmetic result.  相似文献   
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BACKGROUND: Determining the extent of infiltrating lobular carcinoma (ILCA) in the breast is difficult. This study was designed to determine if the size of ILCA on magnetic resonance imaging (MRI) correlated with final pathology. METHODS: Retrospective study of patients between 1998 and 2004, who were evaluated for extent of ILCA prior to definitive treatment, was conducted. Demographic data and radiology and pathology results were obtained. Spearman correlation coefficient was used. RESULTS: Twenty-nine patients (median age 62 years) had MRI of breast. Fourteen patients (48%) had contralateral MRIs; 13 (45%) normal; 1 (8%) prompted core biopsy; 6 of 13 patients underwent contralateral mastectomies, which were benign. The distribution of tumor size was: T1 = 15 (52%); T2 = 7 (24%); T3 = 5 (17%); T4 = 2 (7%). Spearman correlation coefficient between tumor size on ultrasound and MRI with pathology was .19 (P = .5) and .88 (P < .001), respectively. CONCLUSION: MRI provided superior correlation between tumor size and pathology.  相似文献   
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