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1.
BACKGROUND: IgE-mediated carboplatin hypersensitivity reactions occur in up to 30% of patients receiving this agent for chemotherapy of solid tumors, thus limiting therapeutic options. OBJECTIVE: To describe our experience with intravenous carboplatin desensitization regimens, which culminated in a standardized, successful protocol for safe administration. METHODS: Eight consecutive patients with ovarian cancer who had experienced severe anaphylactic reactions to carboplatin were referred to our hospital. Intradermal skin testing was performed by raising a 3-mm bleb by injection of undiluted carboplatin at 10 mg/mL, and the wheal size was read at 20 minutes. The outcomes of the various desensitization regimens were documented prospectively, and the experience gained was used to develop a standardized protocol for administration. RESULTS: All patients had positive intradermal skin test results. The first 3 patients were treated with short (90 minutes to 6 hours) desensitization protocols, and all protocols failed on the first or second infusions. These 3 and a subsequent 5 patients were given intravenous carboplatin according to a protocol of gradual dose escalation over a 4-log dose range given during a 4-day period, with subsequent 3-weekly infusions given more rapidly by omitting the most dilute log dose on each occasion. All patients tolerated the longer infusion protocol without event, and all but 1 patient experienced appropriate tumor marker response. CONCLUSIONS: Short carboplatin desensitization protocols (less than 6 hours) have an unacceptable failure rate in patients with carboplatin allergy, but longer infusion times (days) are well tolerated without recurrence of the allergic reaction and with good tumor response. In cases where carboplatin is the optimal therapeutic agent, clinicians should not be deterred by an anaphylactic reaction to it or by failure of shorter desensitization regimens.  相似文献   
2.
The mechanisms involved in adverse reactions to local anaesthetic (LA) agents are poorly understood. True IgE-mediated reactions appear to be rare. We report a patient with panhypogammaglobulinemia who developed anaphylactoid reactions to two different LAs (lignocaine and procaine), associated with positive intradermal skin tests to these agents as well as prilocaine, despite absent detectable IgE in the serum and a negative RAST test to procaine. We conclude that direct histamine release induced by LA is likely to be the major mechanism in this case.  相似文献   
3.
Client language from a motivational interview (MI) and drug use outcome were investigated. Interview videotapes of 84 drug abusers were coded for frequency and strength of utterances expressing commitment, desire, ability, need, readiness, and reasons to change or maintain their habit. Cluster analysis of proportion days abstinent (PDA) revealed 3 groups: high PDA at intake and follow-up (3, 6, 9, 12 months; maintainers); low intake PDA/high follow-up PDA (changers); and low intake PDA/low to moderate follow-up PDA (stragglers). Distinct group patterns emerged for commitment strength (CS) during MI. Clients dishonest in checklist self-report exhibited CS similar to stragglers. CS for client evaluation of a change plan predicted outcome PDA. CS was predicted by strength of desire, ability, need, and reasons, but more strongly predicted outcome PDA, suggesting CS is a pathway for their influence on behavior.  相似文献   
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CCI-779 is an ester of rapamycin and inhibitor of mammalian target of rapamycin (mTOR) currently in Phase II clinical development for the treatment of patients with cancer. CCI-779 interacts with mTOR and inhibits its kinase activity, resulting in inhibition of the mTOR-regulated translational controllers p70(s6) kinase and 4E-BP1. Ultimately, CCI-779 decreases the translation of mRNAs involved in the control of the cell cycle, resulting in cell cycle arrest. The objective of this study was to develop a method to determine the pharmacodynamic effects of CCI-779 suitable for use in clinical trials. Exposure of Raji lymphoblastoid cells to increasing concentrations of rapamycin resulted in a linear concentration-dependent inhibition of p70(s6) kinase activity, suggesting that p70(s6) kinase activity could be an appropriate marker for mTOR-interacting agents. In subsequent experiments, treatment of nude mice bearing the CCI-779 susceptible breast cancer cell line MDA-468 with a single dose of 10 mg/kg CCI-779 resulted in a >80% inhibition of p70(s6) kinase activity in peripheral blood mononuclear cells (PBMCs) 72 h after treatment. Importantly, the degree of p70(s6) kinase inhibition was identical in PBMCs and simultaneously collected tumor tissue, suggesting that the PBMCs are an adequate surrogate tissue for p70(s6) kinase activity in vivo. The intrasubject coefficient of variation of p70(s6) kinase activity measured in PBMCs collected from five healthy volunteers on days 1, 4, and 8 was 14%, indicating that p70(s6) kinase activity in PBMCs remains relatively stable over time. Finally, p70(s6) kinase activity was measured in PBMCs from nine patients with renal cell cancer treated with a single dose of 25, 75, or 250 mg of CCI-779 i.v. (three patients each). PBMCs were collected on days 2, 4, and 8 after CCI-779 treatment. In this small data set, eight of the nine patients had evidence of p70(s6) kinase activity inhibition after treatment that was independent of the administered dose. There was a significant linear association between time to disease progression and inhibition of p70(s6) kinase activity 24 h after treatment. In conclusion, these results indicate that the pharmacodynamic effects of CCI-779 can be determined using a p70(s6) kinase assay in PBMCs. This assay is currently being incorporated in Phase I and II studies with CCI-779 to determine its relationship with dose and plasma concentration of the agent and its value as a predictor of treatment efficacy.  相似文献   
6.
Black organic coatings and ritual deposits on ancient Egyptian coffins and cartonnage cases are important and understudied sources of evidence about the rituals of funerary practice. Sometimes, the coatings were applied extensively over the surface of the coffin, resembling paint; in other cases, they were poured over the mummy case or wrapped body, presumably as part of a funerary ritual. For this study, multiple samples of black coatings and ritual liquids were taken from 20 Egyptian funerary items dating to a specific time period (c. 943 to 716 BC). Multiple sampling from each object enabled several comparisons to be made: the variability of the black coating within one application, the variability between two applications on one object, and the variability from object to object. All samples were analyzed for lipids using gas chromatography–mass spectrometry (GC-MS), and 51 samples from across the 20 items were further analyzed for the presence of bitumen using solid phase separation followed by selected ion monitoring GC-MS. The majority of the black substances were found to comprise a complex mixture of organic materials, including bitumen from the Dead Sea, conifer resin, and Pistacia resin, providing evidence for a continuation in international trade between Egypt and the eastern Mediterranean after the Late Bronze Age. Both the coating and the anointing liquid are very similar to mummification balms, pointing to parallels with Egyptian embalming rituals and raising questions about the practical aspects of Egyptian funerary practice.

To the ancient Egyptians, black symbolized the underworld and Osiris (often shown with black skin) and also night, especially when used in contrast with yellow and gold (for the sun) and the rich black soil of fertility and regeneration (13). The practice of using black coatings on Egyptian coffins is first attested in the Middle Kingdom (e.g., the cartonnage cases of Nepthys and Hapiankhtifi, Metropolitan Museum of Art 11.150.15 and 12.183.11c.1-0.2) and occurs in the New Kingdom, when black coatings are also used on funerary objects such as divine figures, shabtis, and shabti boxes (35). A secondary application of a black anointing liquid in a funerary context is known from at least as early as the burial of Tjuyu (18th Dynasty, c. 1375 BC), whose gilded funerary mask was anointed with black fluid (6).The application of black substances as coatings and anointing liquids on coffins and mummy cases also occurs in the Third Intermediate Period c. 1086 to 664 BC. This period in Egypt was a time of decentralized rule. In its first phase (21st Dynasty c. 1086 to 943 BC), kings based in the eastern Delta ruled the northern part of Egypt, sharing power with a line of generals, who also acted as high priests of Amun at Thebes, and controlled the southern stretch of the Nile valley. A return to centralized administration in the early 22nd Dynasty (c. 943 to 716 BC) was followed by a gradual fragmentation of the country into smaller political units, some of which were ruled by individuals claiming kingly status, while others were controlled by rulers of Libyan chiefdoms (7), thus Dynasties 22 to 24 and the early 25th Dynasty overlap. The end of the Bronze Age had seen catastrophic events across the eastern Mediterranean, with the Mycenaean and Hittite states collapsing (8, 9). Egypt itself saw incursions and lost control of land in Syria Palestine. Evidence from Egypt and the Levant during this time suggests fluctuating levels of contact and influence (10).During this period, burial practices were changing; instead of a decorated tomb and a wide array of tomb goods, the focus turned toward the body and the coffin (11, 12). The elite continued to lavish expenditure on their burials, but due to high levels of tomb raiding and tomb and coffin appropriation, emphasis was no longer placed on the funerary goods placed in the tomb, as was common in the New Kingdom (13). Instead, the expenditure was concentrated on the body and the coffin, which could be moved to a more secure location if necessary. The 21st Dynasty saw developments in mummification that indicate an increase in the resources allocated for those procedures (14). In the 22nd Dynasty, further changes in the treatment of the body were introduced, most notably the introduction of the cartonnage case, into which the mummy was tightly laced (3). Cartonnage is made with layers of linen, plaster, and glue, similar to papier maché, which can be molded to shape and which dries to make a hard case. These cases were valuable in terms of a vehicle for display as they could be highly decorated and gilded (14), and cartonnage is much more difficult to repurpose than other funerary goods because the body of the deceased is sewn inside. Concentrating resources into the preparation of the body, mummy case, and coffin allowed the elite to display their wealth and power while at the same time securing their investment.Black substances painted on the inside and/or outside of coffins and other funerary items or poured over cartonnage as part of the funerary ritual are a material source of evidence for examining the resourcing of funerary activities during this time of political upheaval. A research project on the 22nd-Dynasty coffins, cartonnage mummy cases, shabti boxes, and Osiris figures in the collection of the British Museum offered the opportunity to address this subject. Using analytical chemistry to examine the complex molecular composition of the black ritual substances, the study aimed to identify the materials used and their likely sources. Determination of chemical composition also offered a means to investigate how the materials were processed and applied as well as patterns of use within the funerary context.Previous research on similar materials has been limited and varied in terms of analytical techniques, covering multiple time periods and considering ritual applications alongside mummification balms (15, 16) or considering a small subset of samples (5, 1719).* By focusing on burial goods of the 22nd Dynasty, this research is a more targeted examination of funerary ritual residues than has been previously undertaken.  相似文献   
7.
The production of immunoglobulin E (IgE) is tightly regulated. This is evidenced by the fact that it comprises less than 0.0001% of serum Ig, and aberrant production causes atopic conditions, including allergy, rhinitis, and anaphylaxis. Interleukin-4 (IL-4) is a well-characterized inducer of IgE by human and murine B cells, whereas interferon-gamma can antagonize this effect. IL-21 has also been recognized for its ability to suppress IL-4-induced IgE production by murine B cells. Here, we identified IL-21 as an inducer of IgE production by CD40L-stimulated human naive B cells. Furthermore, there was a striking synergy between IL-4 and IL-21 on inducing IgE secretion by CD40L-stimulated human B cells, such that the levels detected under these conditions exceeded those induced by IL-4 or IL-21 alone by more than 10-fold. IL-21 induced activation of STAT3 and analysis of B cells from patients with loss-of-function STAT3 mutations revealed that the ability of IL-21 to induce IgE secretion, and augment that driven by IL-4, was STAT3-dependent. These findings highlight a fundamental difference between the regulation of IgE production by human and murine B cells and have implications for the dysregulated production of IgE in conditions characterized by extremely high levels of serum IgE.  相似文献   
8.
Epitopes for 22 alloantibodies that inhibit factor VIII procoagulant protein (FVIII) from multitransfused individuals with severe hemophilia A and three autoantibodies from nonhemophilic individuals appeared to be restricted to two specific regions of the FVIII molecule. Immunoblotting of purified FVIII and purified thrombin-degraded FVIII, followed by reaction with inhibitor plasma samples, monoclonal anti-human IgG3 and IgG4 antibodies, and radiolabeled affinity-purified rabbit anti-mouse IgG, revealed that inhibitor epitopes could be localized to the Mr 72,000 and Mr 44,000 thrombin fragments of FVIII. These two chains are located at the carboxyl terminus and near the amino terminus of the FVIII molecule, respectively. The pattern of reactivity of the inhibitor alloantibodies could be divided into three types: 10 reacted with the Mr 72,000 chain, 3 reacted with the Mr 44,000 chain, and 9 reacted with both of these chains. Among the 3 inhibitor autoantibodies, 1 of each type was found. Ten normal plasmas, as well as 14 plasmas from multitransfused individuals with severe hemophilia A and no inhibitor, were not reactive with the FVIII immunoblots. However, one multitransfused individual with severe hemophilia A and no detectable inhibitor revealed the presence of an antibody reactive with the middle section of the FVIII molecule. The existence of FVIII inhibitor epitopes on both the Mr 72,000 and Mr 44,000 chains raises the possibility that these epitopes might be further restricted to regions of homology between the two chains. These data suggest the possibility of designing inhibitor blocking polypeptides for use as therapeutic agents.  相似文献   
9.
10.
A study was performed to derive susceptibility testing interpretive breakpoints for doxycycline with Streptococcus pneumoniae and to reassess breakpoints for tetracycline using the requirements defined in Clinical and Laboratory Standards Institute (CLSI) document M23-A3. Tetracycline and doxycycline MICs and disk diffusion zone sizes were determined on 189 isolates selected from the 2009-2010 CDC Active Bacterial Core surveillance strain collection according to the testing methods described in CLSI documents M07-A8 and M02-A10. Tetracycline and doxycycline MICs and zones were compared to each other directly, and the reproducibility of MICs and zone diameters for both drugs was determined. Scattergrams of tetracycline MICs versus corresponding zone diameters and doxycycline MICs versus zones were prepared, and analysis indicated that the present CLSI tetracycline MIC and disk breakpoints did not fit the susceptibility data for doxycycline. Doxycycline was 1 to 3 dilutions more potent than tetracycline, especially in strains harboring the tetM resistance determinant. tetM was detected in ≥90% of isolates having tetracycline MICs of ≥4 μg/ml and in ≥90% with doxycycline MICs of ≥1. Limited pharmacokinetic/pharmacodynamic (PK/PD) data coupled with application of the error-rate bounded method of analysis suggested doxycycline-susceptible breakpoints of either ≤0.25 μg/ml or ≤0.5 μg/ml, with intermediate and resistant breakpoints 1 and 2 dilutions higher, respectively. The disk diffusion zone diameter correlates were susceptible at ≥28 mm, intermediate at 25 to 27 mm, and resistant at ≤24 mm. Revised lower tetracycline MIC breakpoints were suggested as susceptible at ≤1 μg/ml, intermediate at 2 μg/ml, and resistant at ≥4 μg/ml. Suggested tetracycline disk diffusion zones were identical to those of doxycycline.  相似文献   
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