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71.
72.
ABSTRACT: The Southern Rural Access Program (SRAP) evaluation team used program logic models to clarify grantees' activities, objectives, and timelines. This information was used to benchmark data from grantees' progress reports to assess the program's successes. This article presents a brief background on the use of program logic models — essentially charts or diagrams specifying a program's planned activities, objectives, and goals- — for evaluating and managing a program. It discusses the structure of the logic models chosen for the SRAP and how the model concept was introduced to the grantees to promote acceptance and use of the models. The article describes how the models helped clarify the program's objectives and helped lead agencies plan and manage the many program initiatives and subcontractors in their states. Models also provided a framework for grantees to report their progress to the National Program Office and evaluators and promoted the evaluators' visibility and acceptance by the grantees. Program logics, however, increased grantees' reporting requirements and demanded substantial time of the evaluators. Program logic models, on balance, proved their merit in the SRAP through their contributions to its management and evaluation and by providing a better understanding of the program's initiatives, successes, and potential impact .  相似文献   
73.
Beckwith  M; Ruscetti  FW; Sing  GK; Urba  WJ; Longo  DL 《Blood》1995,85(9):2461-2470
We wished to examine the role of transforming growth factor-beta (TGF- beta) in the regulation of human lymphoma cell growth. The RL cell line is an immunoglobulin M (IgM)+, IgD+ B lymphoma cell line, which does not constitutively express receptors for TGF-beta, and thus has lost the ability to respond to the inhibitory effects of TGF-beta. We demonstrate here that anti-Ig antibodies can efficiently upregulate the expression of TGF-beta receptors and promote sensitivity to growth inhibition by TGF-beta. Furthermore, because TGF-beta has been shown to function in late G1 of the cell cycle, we examined the ability of TGF- beta to modulate two tumor suppressor proteins known to be critical regulators of the G1/S transition, Rb and p53. Rb is a 105- to 110-kD phosphoprotein, which has been shown to maintain its growth suppressive function when it is found in the hypophosphorylated state. Wild-type p53 is a 53-kD phosphoprotein that appears to be important in preventing cell-cycle progression and promoting apoptosis in cells with DNA damage, whereas mutant p53 can overcome those functions. We show here that TGF-beta treatment of phorbol myristate acetate (PMA) or anti- Ig-activated RL cells results in growth inhibition through a dual effect on Rb and mutant p53. After TGF-beta treatment, we observe a predominance of Rb in the hypophosphorylated, growth suppressive form. In addition, we show a decrease in levels of mRNA and protein for mutant p53. We also show that, although these changes are sufficient to halt progression through the cell cycle, the cells do not appear to undergo extensive programmed cell death following 72 hours of TGF-beta treatment. Thus, although these lymphoma cells maintain the capacity to be negatively growth regulated by TGF-beta, the ability of TGF-beta to induce apoptosis must be independently controlled.  相似文献   
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75.
Hydatidiform moles are pregnancies characterized by abnormal development of both embryonic and extraembryonic tissues and are associated with the misexpression of imprinted genes. The vast majority of complete hydatidiform moles are diploid and androgenetic, whereas partial hydatidiform moles are triploid, with an extra set of chromosomes of paternal origin. Here, we present an unusual complete mole that showed strong expression of two imprinted, maternally transcribed genes, CDKN1C (encoding p57(KIP2)) and PHLDA2 (TSSC3/IPL), both part of a large imprinted gene domain on chromosome 11. Using microsatellite genotyping and fluorescent in situ hybridization, we show that this paradoxical gene expression was due to retention of a maternal copy of chromosome 11 in addition to the two paternal copies normally present in complete moles. These findings demonstrate that, despite being predominantly androgenetic, some complete moles contain small amounts of DNA of maternal origin. Furthermore, these results provide an explanation for rare false negatives that can arise when p57(KIP2) is used as a diagnostic marker for complete moles.  相似文献   
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77.
PURPOSE: To determine the clinical utility of ultrasound biomicroscopy (UBM) in diagnosis of pseudoexfoliation (PEX) syndrome by characterizing the lens capsule and zonules before cataract surgery. SETTING: Veterans Administration Hospital, East Orange, and University of Medicine & Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey, USA. METHODS: Ultrasound biomicroscopy was performed on 10 patients clinically diagnosed with PEX syndrome. The clinical diagnosis was made by the presence of fibrillin deposits on the anterior lens capsule, lack of pigment at the pupillary ruff, and poor pharmacologic dilation. Five persons without PEX were used as controls. The thickness of the anterior lens capsule was measured in 5 locations in each eye: centrally and in the peripheral lens capsule superiorly, inferiorly, nasally, and temporally. Four measurements were taken from the zonule at the thickest point on each fiber. The UBM also found the presence or absence of nodular deposits on the zonules. RESULTS: The anterior and peripheral lens capsule in patients with PEX was thicker than that in the control group. Additionally, patients with PEX had thicker zonules than the control group and had nodular deposits present; the control group had no deposits. These differences were all significant with a 99% confidence interval. CONCLUSIONS: A thicker anterior lens capsule and lens zonule nodules were associated with PEX. These abnormalities can be visualized with the UBM to confirm the diagnosis of PEX and identify patients at risk for operative complications.  相似文献   
78.
Adenovirus serotypes isolated from ocular infections in London.   总被引:2,自引:1,他引:1       下载免费PDF全文
During the period 1973-8 700 adenoviruses were isolated from the eyes of patients presenting at Moorfields Eye Hospital. Of these, 678 were serotyped by a neutralisation test. Twenty-one different serotypes were identified. Serotype 3, 7, and 10 accounted for 68% of the isolates, 4, 8, 15 (15/29), and 19 for 25%, and the other 14 serotypes for 7%. Community outbreaks of ocular infections by adenovirus 3, 4, 7, 10, and 15 (15/29) were observed. Outbreaks with adenovirus 3, 7, and 10 appeared to continue for 2 years or more, whereas outbreaks with 4 and 15 (15/29) were restricted to one year or less. Hospital outbreaks by adenovirus 8 and 19 were also recorded. During the same period 18 of these 21 adenovirus serotypes were isolated from the nonocular sites (mainly respiratory tract) in 7804 cases. There was a close association in the distribution of adenovirus 1, 2, 3, 5, and 6 in the ocular and nonocular sites. No such association was observed for adenovirus serotypes 4, 8, 10, 15 (15/29), and 19.  相似文献   
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80.
A comparison has been made of the efficiency of 3 cell systems, human embryo kidney (HEK), Hep 2, and a continuous line of human embryo intestine (HEI), for the isolation of ophthalmic viruses. A total of 40 herpes simplex, 51 adenoviruses, and 2 vaccinia viruses were isolated from 323 specimens. HEK cells were found to be the optimal system, 85 out of 93 (91%) of the viruses being detected in these cells alone. However, HEK cells are difficult to obtain, and therefore the use of a combination of the continuous cell lines HEI and Hep 2 is recommended as an alternative. 89% of the viruses were detected by this combination. The use of either HEI or Hep 2 cells alone was unsatisfactory.  相似文献   
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