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31.
New iodinated radiological contrast media, which are safer but much more expensive than the conventional ones, have been introduced. Since the financial implications are considerable a compromise between cost and safety is inevitable. It is therefore recommended that, at present, the conventional media be used routinely and the new media be reserved for potentially painful examinations and for patients at higher risk. Should a question of wrongfulness or negligence concerning the use of contrast media be considered by our courts, they will undoubtedly be influenced by what is considered 'common practice' and 'accepted practice' within a medical specialty and that may be co-determined by socio-economic considerations. 相似文献
32.
M S Bahrke J E Wright R H Strauss D H Catlin 《The American journal of sports medicine》1992,20(6):717-724
To assess physiological and psychological states accompanying anabolic-androgenic steroid use, male weight lifters 1) were interviewed regarding their physical training and the patterns and effects of any drug use; 2) completed a written physical and medical history questionnaire, a Profile of Mood States questionnaire, and the Buss-Durkee Hostility Inventory; and 3) were physically examined, including a blood sample and urinalysis. Subjects were divided into current anabolic-androgenic steroid users (N = 12), previous users (N = 14), and nonusers (N = 24). Current and previous users reported the following changes associated with anabolic-androgenic steroid use: increases in enthusiasm, aggression, and irritability; changes in insomnia, muscle size, muscle strength and density; faster recovery from workouts and injuries; and changes in libido. We were unable to confirm these interview and physical and medical history questionnaire responses using standardized and well-accepted psychological inventories. There were no significant differences among groups for any Profile of Moods factor, total mood disturbance, total Buss-Durkee Hostility Inventory score, or any subscale. For current users, there were no significant correlations between either total weekly drug dose or length of time on the current cycle of anabolic-androgenic steroids and any individual scale of the Profile of Mood States, Buss-Durkee Hostility Inventory, Profile of Mood States total mood disturbance, or composite Buss-Durkee Hostility Inventory score. Furthermore, anabolic-androgenic steroid users did not differ in their responses on these inventories from nonusers or from general population norms.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
33.
The insulin-like growth factor, somatomedin-C, modulates low density lipoprotein metabolism by swine granulosa cells 总被引:1,自引:0,他引:1
Insulin-like growth factor I (IGF-I) synergistically amplified the stimulatory effect of low density lipoprotein (LDL) on progesterone biosynthesis by primary cultures of swine ovarian cells. The mechanisms subserving this facilitative interaction included the following. IGF-I's synergism with LDL was associated with a decrease in the mean half-maximally stimulatory concentration of LDL from 20-3.5 micrograms/ml. IGF-I increased by 3- to 6-fold the number of specific high affinity LDL receptors on ovarian cells, with no change in apparent binding affinity. IGF-I augmented by 3- and 18-fold the maximal rates of [125I]iodo-LDL internalization and degradation, respectively, without altering half-maximally effective concentrations of LDL supporting these processes. IGF-I increased by 2- to 2.5-fold the total mass of free and esterified cholesterol contained in granulosa cells. IGF-I stimulated the intracellular accumulation of free [3H]cholesterol and [3H]cholesteryl ester from exogenous [3H]cholesteryl linoleate-labeled LDL, and amplified [3H]progesterone secretion by granulosa cells exposed to this source of lipoprotein-borne sterol. These actions of IGF-I were demonstrated at 30- to 100-fold lower concentrations of IGF-I than insulin. We conclude that IGF-I and LDL synergistically enhance progesterone biosynthesis by ovarian cells. This synergism occurs in part via mechanisms that regulate the effectual delivery of lipoprotein-borne cholesterol substrate into cellular sterol pools that participate in steroid hormone biosynthesis. 相似文献
34.
Donald F. Orton M.D. Dennis F. Strauss M.D. Michael Hummel M.D. Dale Orton M.D. F.A.C.E.P. 《Emergency radiology》1998,5(3):173-175
The intraperitoneal mass most commonly encountered after blunt abdominal truama is a hematoma. However, one must also consider
unusual bulky tumors that can have imaging characteristics similar to those of hematoma. The most typical of these neoplasms
is lymphoma, but a desmoplastic small cell tumor also may be observed. The presentation and imaging findings of a desmoplastic
small tumor are described. 相似文献
35.
36.
In recent years, partial hospitalization programs have become an accepted major component of community-based care for psychiatric patients. Studies have shown that partial hospitalization is at least as effective as inpatient hospitalization in treating a spectrum of psychiatric disorders and is substantially more cost effective than standard inpatient care (Guillette et al. 1978; Herz et al. 1971; Washburn et al. 1976; Wilder et al. 1966). Despite these positive findings, the therapeutic factors that contribute to the effectiveness of partial hospitalization continue to be a subject of speculation (e.g., Goldberg 1982; Vannicelli et al. 1978; Washburn 1983). In a recent review of the literature on the efficacy of partial hospitalization, Mason et al. (1982) emphasize that the "active ingredient" in this treatment modality remains unclear. In an outcome study by Dunn et al. (1982, p. 297), hope was expressed that "future studies might best explore which nonspecific factors are most powerful therapeutically." The current study is part of a larger effort to develop from an empirical base a comprehensive model of partial hospitalization. The comprehensive model provides a framework for understanding partial hospitalization by examining: 1) the functions of a partial hospital admission, 2) the types of patient changes that occur in these programs, 3) the processes of change, and 4) the therapeutic factors that appear to facilitate change. Findings regarding the first three elements of the model are described in a companion paper. This report focuses on the findings regarding the fourth element of the model, the therapeutic factors that appear to facilitate change in a short-term partial hospitalization program. It also examines how specific program components contribute to these therapeutic factors. 相似文献
37.
J S Strauss 《Psychiatry》1989,52(3):336-338
Suzanne Retzinger's article, "A Theory of Mental Illness," provides further untangling of the complex links between social relationships and psychopathology. Those links have been demonstrated in such diverse areas as the impact of family relationships on relapse (e.g., Brown et al. 1972), the predictive importance of social relations to outcome (e.g., Strauss and Carpenter 1977), and the genetic connections between social relationship traits and vulnerability to psychopathology (Kendler et al. 1982). The research presented here focuses on social relationships with special emphasis on stigma in those relationships and its impact on disorder. It also has the valuable role of forging connections between the more abstract labeling theory and the actual behaviors of people as viewed in their interaction. 相似文献
38.
Coexpression of galanin and adrenocorticotropic hormone in human pituitary and pituitary adenomas.
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D. W. Hsu S. C. Hooi E. T. Hedley-Whyte R. M. Strauss L. M. Kaplan 《The American journal of pathology》1991,138(4):897-909
Galanin is a neuropeptide that regulates the secretion of several pituitary hormones, including prolactin (PRL) and growth hormone (GH). Galaninlike immunoreactivity (Gal-IR) and galanin mRNA in the rat anterior pituitary is cell lineage specific, with predominant expression in lactotrophs and somatotrophs. The authors examined the cellular distribution of human Gal-IR in seven normal postmortem pituitaries and 62 pituitary tumors by immunoperoxidase staining. In contrast to the rat, Gal-IR in human anterior pituitaries was present in corticotrophs scattered throughout the gland, but not in lactotrophs, somatotrophs, thyrotrophs, or gonadotrophs. Distinct Gal-IR also was present in hyperplastic and neoplastic corticotrophs in 19 of 22 patients with Cushing's disease. In noncorticotroph cell tumors, unequivocal Gal-IR was present in 5 of 11 GH-secreting tumors associated with clinical acromegaly, 9 of 18 nonfunctioning pituitary adenomas, and 2 of 14 prolactinomas. Of these galanin-positive tumors, four of the five GH-secreting adenomas, six of the nine nonfunctioning adenomas, and both of the prolactinomas also contained adrenocorticotropic hormone immunoreactivity (ACTH-IR). Immunostaining and in situ hybridization on adjacent sections using an 35S-labeled probe complementary to human galanin mRNA demonstrated predominant galanin expression in normal corticotrophs. Immunoelectron microscopy confirmed the presence of Gal-IR in pituitary cells characteristic of corticotrophs in both normal and neoplastic pituitaries. Thus, as in the rat, galanin gene expression in the human pituitary is cell-type specific. Unlike the rat, however, human galanin gene expression is restricted to the corticotroph lineage. Studies of tumors confirmed the observed coexpression of galanin and adrenocorticotropic hormone. The divergent cell type specificity of galanin production in human and rat pituitaries reflects different patterns of gene activation in these two species. In addition, these results suggest that galanin in the human pituitary may participate locally in the regulation of the hypothalamic-pituitary-adrenal axis. 相似文献
39.
Decorin inhibition of PDGF-stimulated vascular smooth muscle cell function: potential mechanism for inhibition of intimal hyperplasia after balloon angioplasty
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Nili N Cheema AN Giordano FJ Barolet AW Babaei S Hickey R Eskandarian MR Smeets M Butany J Pasterkamp G Strauss BH 《The American journal of pathology》2003,163(3):869-878
Decorin is a small proteoglycan that binds to transforming growth factor-beta (TGF-beta) and inhibits its activity. However, its interaction with platelet-derived growth factor (PDGF), involved in arterial repair after injury, is not well characterized. The objectives of this study were to assess decorin-PDGF and decorin-PDGF receptor (PDGFR) interactions, the in vitro effects of decorin on PDGF-stimulated smooth muscle cell (SMC) functions and the in vivo effects of decorin overexpression on arterial repair in a rabbit carotid balloon-injury model. Decorin binding to PDGF was demonstrated by solid-phase binding and affinity cross-linking assays. Decorin potently inhibited PDGF-stimulated PDGFR phosphorylation. Pretreatment of rabbit aortic SMC with decorin significantly inhibited PDGF-stimulated cell migration, proliferation, and collagen synthesis. Decorin overexpression by adenoviral-mediated gene transfection in balloon-injured carotid arteries significantly decreased intimal cross-sectional area and collagen content by approximately 50% at 10 weeks compared to beta-galactosidase-transfected or balloon-injured, non-transfected controls. This study shows that decorin binds to PDGF and inhibits its stimulatory activity on SMCs by preventing PDGFR phosphorylation. Decorin overexpression reduces intimal hyperplasia and collagen content after arterial injury. Decorin may be an effective therapy for the prevention of intimal hyperplasia after balloon angioplasty. 相似文献
40.