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1.
2.
Terry?O?Herndon Salvador?Gonzalez TR?Gowrishankar R?Rox?Anderson James?C?WeaverEmail author 《BMC medicine》2004,2(1):12
Background
Painless, rapid, controlled, minimally invasive molecular transport across human skin for drug delivery and analyte acquisition is of widespread interest. Creation of microconduits through the stratum corneum and epidermis is achieved by stochastic scissioning events localized to typically 250 μm diameter areas of human skin in vivo. 相似文献3.
Eighty four out of 2151 militancy trauma patients sustained severe maxillofacial injury from Jan 1990 to March 1993. The resuscitation, stabilisation and intensive care of these patients was based on management priorities of primary resuscitation, care of airway, management of haemodynamics, oxygenation and monitoring. Anaesthesia was administered in a situation when the airway was likely to be compromised and the patients were critically sick. Initial ventilation and oxygenation was the most difficult and could be achieved with satisfactory seal around the face mask by applying water-soaked guaze pieces around the mouth and nose to “fill-in” the defects. Tracheal intubation could be accomplished with intravenous sedation by an experienced anaesthesiologist. Dental occlusion and wiring necessiated the placement of nasotracheal tube for 48-72 hours after surgery.KEY WORDS: Trauma, Maxillofacial injury, Trauma anesthesia, Anaesthesia and critical care 相似文献
4.
OBJECTIVE: Because survival from admission to discharge does not provide parents and physicians information about future life expectancy in the premature neonate, we characterized the actuarial survival, defined as the future life expectancy from a given postnatal age, in a large inborn population of premature infants < 30 weeks' gestation. STUDY DESIGN: We determined daily actuarial survival of 1925 inborn infants (23 to 29 weeks' gestation) admitted to the Baylor Affiliated Nurseries from July 1986 through December 1994, stratified by 100-g birth weight and by 1-week gestational-age intervals. RESULTS: In the 501- to 600-g birth weight stratum, actuarial survival improved from 31% at birth, to 61% on day of life 7, and then to 75% on day of life 28; in the 901- to 1000-g birth weight stratum, actuarial survival improved from 88%, to 94%, and then to 98% throughout the same times, respectively. Similar trends were obtained when data were stratified by gestational age. CONCLUSIONS: Survival in the smallest infants improves dramatically during the first few days of life, but there is a significant risk for late death in the smallest of these infants. 相似文献
5.
Gonzales AJ; Christensen JG; Preston RJ; Goldsworthy TL; Tlsty TD; Fox TR 《Carcinogenesis》1998,19(7):1173-1183
6.
健康人通过体内胰岛素的分泌调节,可以保持正常的血糖水平。各种外源性胰岛素制剂在代谢过程上总是尽可能地模拟内源性胰岛素的分泌动力学。理想的外源性基础胰岛素制剂可以模拟健康人的基础胰岛素分泌,以致使用者可以恢复两餐之间和夜间正常生理情况下的血浆胰岛素水平。 相似文献
7.
Dr. Timothy R. Dresselhaus MD MPH Jeff Luck PhD MBA Brian C. Wright Roger G. Spragg MD Martin L. Lee PhD Samuel A. Bozzette MD PhD 《Journal of general internal medicine》1998,13(8):534-540
OBJECTIVE: To determine time allocation and the perceived value to education and patient care of the weekday activities of internal
medicine housestaff on inpatient rotations and to compare the work activities of interns and residents.
DESIGN: An observational study. We classified activities along five dimensions (association, location, activity, time, and value),
developed a computer-assisted self-interview survey, and demonstrated its face and content validity, internal consistency,
and interrater reliability. Subjects were assigned survey computers for 5 consecutive weekdays over a 24-week period, into
which they entered data when prompted several times a day.
SETTING: The medical service of a university-affiliated Veterans Administration Medical Center.
PARTICIPANTS: Sixty housestaff (36 interns, 24 residents) rotating on the inpatient wards.
MEASUREMENTS AND MAIN RESULTS: We analyzed activities according to content (direct patient care, indirect patient care, education), association, and location.
Likert-scale ratings of perceived value to education and patient care were also obtained. Housestaff provided complete responses
to 3,812 (95%) of 3,992 prompts by a median of 11 seconds; 93% of responses were logically consistent across the measured
dimensions. Housestaff spent more time in indirect patient care (56%) than in direct patient care (14%) or educational activities
(45%). Formal educational activities had the highest educational value (66 on 0–100 scale), and direct care had the highest
value to patient care (81). Over 30% of time was spent in administrative activities, which had low educational value (40).
Compared with residents, interns allocated significantly less time to educational activities (38% vs 57%) and more time to
lower-value activities such as documentation (19% vs 12%).
CONCLUSIONS: Improved data collection methods demonstrate that housestaff in our program, particularly interns, spend much of their workday
in activities that are low in educational and patient care value. Selective elimination or delegation of such activities would
preserve higher-value experiences during reductions in overall inpatient training time. Planners can use automated random
sampling to guide the rational redesign of housestaff work.
Support for this work was provided by the Western Region of the Veterans Administration (Ambulatory Care and Education Initiative,
94–04), the Veterans Administration Center for the Study of Provider Behavior, and the RAND Graduate School. Dr. Bozzette
is a Senior Research Associate of the HSR&D Service, Department of Veterans Affairs. 相似文献
8.
Systemic hematologic effects of PEG-rHuMGDF-induced megakaryocyte hyperplasia in mice 总被引:3,自引:3,他引:3
Ulich TR; del Castillo J; Senaldi G; Kinstler O; Yin S; Kaufman S; Tarpley J; Choi E; Kirley T; Hunt P; Sheridan WP 《Blood》1996,87(12):5006-5015
PEG-rHuMGDF injected daily in normal mice causes a rapid dose-dependent increase in megakaryocytes and platelets. At the same time that platelet numbers are increased, the mean platelet volume (MPV) and platelet distribution width (PDW) can be either decreased, normal, or increased depending on the dose and time after administration. Thus, PEG-rHuMGDF at a low dose causes decreases in MPV and PDW, MGDF at an intermediate dose causes an initial increase followed by a decrease in MPV and PDW, and PEG-rHuMGDF at higher doses causes an increase in MPV and PDW followed by a gradual normalization of these platelet indices. In addition to the expected thrombocytosis after 7 to 10 days of daily injection of high doses of PEG-rHuMGDF, a transient decrease in peripheral red blood cell numbers and hemoglobin is noted accompanied in the bone marrow by megakaryocytic hyperplasia, myeloid hyperplasia, erythroid and lymphoid hypoplasia, and deposition of a fine network of reticulin fibers. Splenomegaly, an increase in splenic megakaryocytes, and extramedullary hematopoiesis accompany the hematologic changes in the peripheral blood and marrow to complete a spectrum of pathologic features similar to those reported in patients with myelofibrosis and megakaryocyte hyperplasia. However, all the PEG-rHuMGDF-initiated hematopathology including the increase in marrow reticulin is completely and rapidly reversible upon the cessation of administration of PEG-rHuMGDF. Thus, transient hyperplastic proliferation of megakaryocytes does not cause irreversible tissue injury. Furthermore, PEG-rHuMGDF completely ameliorates carboplatin-induced thrombocytopenia at a low-dose that does not cause the hematopathology associated with myelofibrosis. 相似文献
9.
Jae-Young Hong Seung-Woo Suh Easwar TR Suk Joo Hong Yong-Chul Yoon Hyung-Jin Kang 《The spine journal》2013,13(11):1510-1520
Background contextFew accurate analyses of clinically useful vertebral anatomy have been conducted, and most have focused on thoracic idiopathic scoliosis.PurposeTo evaluate the different anatomic characteristics in scoliosis by disease type and level.Study designObservational cohort study.Patient sampleForty-eight patients with scoliosis were included in this study.Outcome measuresSubjects underwent computed tomography (CT) of the whole spine.MethodsForty-eight patients with scoliosis were included in this study: 15 adolescent idiopathic, 11 cerebral palsy (CP), 10 muscular dystrophy (MD), and 12 congenital (CG) scoliosis patients with similar demographics. Subjects underwent CT of the whole spine, preoperatively. Eight anatomic parameters were measured in multiplanar reconstructive CT images, and statistical analysis was performed to investigate differences.ResultsIn general, values in the anatomic parameters were similar for the four diseases. Each parameter showed the unique change pattern according to the spinal level regardless of curvature shape, direction, or magnitude. In particular, chord length (CL) in MD and CG scoliosis was lower than in adolescent idiopathic scoliosis (AIS) and CP, and pedicle rib unit length was lower in CG scoliosis than in the other diseases (p<.05). Comparisons of convex and concave anatomies in AIS showed that inner pedicle width (PWI) and outer pedicle width (PWO) were wider for convex side, CL, pedicle width, and transverse pedicle angle were greater for concave side (p<.05), and differences were more significant at apices. However, in CP, PWI and PWO were similar between convex and concaves sides (p>.05). Although PWI and PWO were wider for convex sides and CL and pedicle length were greater for concave sides in MD (p<.05), differences were less significant at apices. Particularly, CG scoliosis showed severely deformed anatomy, with differences of seven parameters at apical vertebrae (p<.05).ConclusionClinical anatomies of vertebrae in scoliosis were found to differ significantly at different levels and in terms of convexity and disease type. 相似文献
10.
Structural changes in bacteriorhodopsin during proton translocation revealed by neutron diffraction. 总被引:16,自引:7,他引:16 下载免费PDF全文
N A Dencher D Dresselhaus G Zaccai G Büldt 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(20):7876-7879
A neutron diffraction study of spectroscopic states for the light-energized proton pump bacteriorhodopsin (BR) is presented. The photocycle states BR-568 and M were generated at temperatures above 4 degrees C and were measured after trapping at--180 degrees C. In the BR-568 to M-state transition, which is known to be a key step in transmembrane proton pumping, reversible structural changes of the protein were detected. These structural alterations occur in the neighborhood of the cyclohexene ring and at the Schiff's base end of the chromophore retinal. They are interpreted as a 1-2 degree tilt of three or four of the transmembrane alpha-helices or as positional changes of four or five amino acids. The structural changes observed are inherent in the transport mechanism of bacteriorhodopsin. 相似文献