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421.
Impact of zinc supplementation on persistent diarrhoea in malnourished Bangladeshi children 总被引:1,自引:0,他引:1
SK Roy AM Tomkins D Mahalanabis SM Akramuzzaman R Haider RH Behrens G Fuchs 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(12):1235-1239
To evaluate the impact of zinc supplementation on the clinical recovery and body weight of children with persistent diarrhoea, a randomized, double-blind, controlled trial was conducted in 190 children with persistent diarrhoea aged between 3 and 24 months. Children were randomly allocated to receive either zinc (20 mg d−1 ) syrup with multivitamin (2 × RDA) or multivitamin alone in three divided daily doses for 2 weeks. The trial was conducted in a diarrhoeal disease hospital in Dhaka, Bangladesh. Duration until clinical recovery (d), impact on body weight and serum zinc level after 2 weeks of zinc supplementation were recorded. The duration of illness was significantly reduced (33%) with zinc supplementation among children who were underweight (≤70% wt/age, p = 0:03). Supplemented male children also had a significant reduction (27%) in duration for recovery compared with unsupplemented children ( p = 0:05). From baseline to convalescence, zinc-supplemented children maintained their serum zinc concentration (13.4 vs 13.6/ μ mol l−1 ), whereas unsupplemented children had a decrease in serum zinc after the 2 weeks of diarrhoea (13.6 vs 11.8 μ mol l−1 , p < 0:03). The mean body weight of the children in the supplemented group was maintained (5.72 vs 5.70 kg, p = 0:62) during hospitalization, unlike that of the control group, in which there was a reduction in body weight (5.75 vs 5.67 kg, p = 0:05). Five children in the unsupplemented group and one child in the zinc-supplemented group died during the 2 weeks of supplementation ( p = 0:06). Zinc supplementation in persistent diarrhoea significantly reduced the length of the recovery period in malnourished children and prevented a fall in body weight and serum zinc concentration, indicating that zinc is a beneficial therapeutic strategy in this high-risk childhood illness. 相似文献
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ME Christian HC Davidsonl RH rd Wiggins G Berges G Cannon G Jackson B Chapman HR Harnsberger 《Journal of digital imaging》2002,14(1):14-17
Several studies have addressed the implications of filmless radiologic imaging on telemedicine, diagnostic ability, and electronic
teaching files. However, many publishers still require authors to submit hard-copy images for publication of articles and
textbooks. This study compares the quality digital images directly exported from picture archive and communications systems
(PACS) to images digitized from radiographic film. The authors evaluated the quality of publication-grade glossy photographs
produced from digital radiographic images using 3 different methods: (1) film images digitized using a desktop scanner and
then printed, (2) digital images obtained directly from PACS then printed, and (3) digital images obtained from PACS and processed
to improve sharpness prior to printing. Twenty images were printed using each of the 3 different methods and rated for quality
by 7 radiologists. The results were analyzed for statistically significant differences among the image sets. Subjective evaluations
of the filmless images found them to be of equal or better quality than the digitized images. Direct electronic transfer of
PACS images reduces the number of steps involved in creating publication-quality images as well as providing the means to
produce high-quality radiographic images in a digital environment. 相似文献
424.
In order to establish appropriate culture temperatures for in-vitro
maturation of pig ovarian oocytes, large Graafian follicles (7-10 mm
diameter) were sensed by infra-red technology during the latter part of a
spontaneous oestrous cycle. Temperatures were measured under systemic
anaesthesia almost instantaneously upon revealing the ovaries at mid-
ventral laparotomy. Temperature differentials were observed within all 16
ovaries sensed in 14 animals. Ovaries were always cooler than deep rectal
temperatures (mean rectal temperature was 38.0 +/- 0.4 degrees C; range
37.5-38.6 degrees C) and mature follicles always cooler than ovarian stroma
(35.6 +/- 0.3 degrees C versus 37.3 +/- 0.2 degrees C respectively; P <
0.01). Such follicles were frequently 1.5-1.8 degrees C cooler than the
adjacent stroma, the mean being 1.7 +/- 0.4 degrees C. Small Graafian
follicles (< 5-6 mm diameter) and recent ovulations did not show this
differential. The control experiment of excising an ovary, deep freezing it
in liquid nitrogen, and then restoring it to the body cavity before further
sensing indicated that intra-ovarian temperature gradients depended on the
activity of living tissues and/or a functional blood supply. Furthermore,
calculation of anticipated rates of cooling for exposed Graafian follicles
strongly suggested that artefacts could not have been solely responsible
for the observed temperatures. Endothermic reactions within mature
follicles were thus brought into focus. It is concluded that follicular
temperatures may influence the meiotic progression and cytoplasmic
maturation of oocytes and act to regulate enzymatic activity in the
biosynthetic pathways for steroid and/or peptide hormones.
相似文献
425.
OBJECTIVE: This study is one of the first to examine the association between sexual orientation and health risk behaviors among a representative, school-based sample of adolescents. DESIGN: This study was conducted on an anonymous, representative sample of 4159 9th- to 12th-grade students in public high schools from Massachusetts' expanded Centers for Disease Control and Prevention 1995 Youth Risk Behavior Survey. Sexual orientation was determined by the following question: "Which of the following best describes you?" A total of 104 students self-identified as gay, lesbian, or bisexual (GLB), representing 2.5% of the overall population. Of GLB youth, 66.7% were male and 70% were white (not Hispanic). Health risk and problem behaviors were analyzed comparing GLB youth and their peers. Those variables found to be significantly associated with GLB youth were then analyzed by multiple logistic regression models. RESULTS: GLB youth were more likely than their peers to have been victimized and threatened and to have been engaged in a variety of risk behaviors including suicidal ideation and attempts, multiple substance use, and sexual risk behaviors. Four separate logistic regression models were constructed. Model I, Onset of Behaviors Before Age 13, showed use of cocaine before age 13 years as strongly associated with GLB orientation (odds ratio [OR]: 6.10; 95% confidence interval [CI] = 2.45-15.20). Early initiation of sexual intercourse (2.15; 10.6-4.38), marijuana use (1.98; 1.04-4.09), and alcohol use (1.82; 1.03-3.23) also was associated with GLB orientation. Model II, Lifetime Frequencies of Behaviors, showed that frequency of crack cocaine use (1.38; 1.06-1.79), inhalant use (1.30; 1.05-1.61), and number of sexual partners (1.27; 1.06-1.43) was associated with GLB orientation. Model III, Frequency of Recent Behaviors, showed smokeless tobacco use in the past 30 days (1.38; 1. 20-1.59) and number of sexual partners in the previous 3 months (1. 47; 1.31-1.65) were associated with GLB orientation. Model IV, Frequency of Behaviors at School, showed having one's property stolen or deliberately damaged (1.23; 1.08-1.40) and using marijuana (1.29; 1.05-1.59) and smokeless tobacco (1.53; 1.30-1.81) were associated with GLB orientation. Overall, GLB respondents engaged disproportionately in multiple risk behaviors, reporting an increased mean number of risk behaviors (mean = 6.81 +/- 4.49) compared with the overall student population (mean = 3.45 +/- 3.15). CONCLUSION: GLB youth who self-identify during high school report disproportionate risk for a variety of health risk and problem behaviors, including suicide, victimization, sexual risk behaviors, and multiple substance use. In addition, these youth are more likely to report engaging in multiple risk behaviors and initiating risk behaviors at an earlier age than are their peers. These findings suggest that educational efforts, prevention programs, and health services must be designed to address the unique needs of GLB youth. 相似文献
426.
Detection of drug-dependent, platelet-reactive antibodies by antigen- capture ELISA and flow cytometry 总被引:7,自引:0,他引:7
The effectiveness of flow cytometry in the detection of drug-dependent, platelet-reactive antibodies was investigated. In studies of seven sera known to contain quinine- or quinidine-dependent, platelet-reactive antibodies, flow cytometry was 5 to 10 times more sensitive in detecting drug-dependent antibodies (DDAbs) than the 51Cr release assay, antigen-capture enzyme-linked immunosorbent assay (ELISA), and indirect immunofluorescence microscopic assay. With flow cytometry, DDAbs could be detected at drug concentrations as low as 0.1 microM, or less than one-tenth the level required with other methods. Antigen-capture ELISA was not as sensitive as flow cytometry in DDAb detection, but it did allow identification of the DDAbs' target molecules. With this assay, five of the seven DDAbs recognized both the glycoprotein Ib/IX (GPIb/IX) and glycoprotein IIb/IIIa (GPIIb/IIIa) complexes, while the remaining two sera reacted only with GPIb/IX. Of 44 consecutive patients who developed thrombocytopenia while taking quinidine, DDAbs were detected by flow cytometry in 11 (25%), more than twice the number detected by other methods. In one patient who developed thrombocytopenia while taking trimethoprim/sulfamethoxazole, DDAbs could be detected only by flow cytometry. It can be concluded that flow cytometry is highly sensitive in detecting DDAbs and allows their detection at pharmacologic concentrations of the drug. Most quinidine-dependent antibodies recognize at least two different glycoprotein complexes in the platelet membrane. 相似文献
427.
Recovery and survival in vivo of platelet concentrates prepared with prostaglandin E1 总被引:1,自引:0,他引:1
In follow-up to previous studies showing that stimulators of adenylate cyclase inhibit the activation of platelets in platelet concentrates (PC), the posttransfusion recovery and survival of autologous platelets prepared and stored after the addition of prostaglandin E1 (PGE1) to platelet-rich plasma at a concentration of 1.3 X 10(-8) M were investigated. Six normal subjects were studied on the two occasions, using PC stored with and without PGE1 and radiolabeling with 51Cr. The mean recovery of platelets prepared with PGE1 (35.2 +/- 8.1%) was significantly lower (p less than 0.013) than that of routinely prepared platelet concentrates (46.3 +/- 9.4%). The mean life-spans of platelets prepared with and without PGE1 were 7.1 +/- 0.4 and 6.2 +/- 1.0 days, respectively (p = NS). Despite its ability to inhibit the activation of platelets during concentration and storage, prostaglandin E1 appears to reduce posttransfusion recovery of platelets significantly in this experimental model and cannot be recommended at this time as an adjunct for PC preparation. 相似文献
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