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排序方式: 共有7584条查询结果,搜索用时 312 毫秒
41.
John P. McCarthy Marcas M. Bamman Janice M. Yelle Adrian D. LeBlanc Roger M. Rowe Michael C. Greenisen Stuart M. C. Lee Elisabeth R. Spector Suzanne M. Fortney 《European journal of applied physiology》1997,76(1):32-40
Resistance exercise has been suggested to increase blood volume, increase the sensitivity of the carotid baroreceptor cardiac reflex response (BARO), and decrease leg compliance, all factors that are expected to improve orthostatic tolerance. To further test these hypotheses, cardiovascular responses to standing and to pre-syncopal limited lower body negative pressure (LBNP) were measured in two groups of sedentary men before and after a 12-week period of either exercise (n = 10) or no exercise (control, n = 9). Resistance exercise training consisted of nine isotonic exercises, four sets of each, 3 days per week, stressing all major muscle groups. After exercise training, leg muscle volumes increased (P?0.05) by 4–14%, lean body mass increased (P = 0.00) by 2.0 (0.5)?kg, leg compliance and BARO were not significantly altered, and the maximal LBNP tolerated without pre-syncope was not significantly different. Supine resting heart rate was reduced (P = 0.03) without attenuating the heart rate or blood pressure responses during the stand test or LBNP. Also, blood volume (125I and 51Cr) and red cell mass were increased (P?0.02) by 2.8% and 3.9%, respectively. These findings indicate that intense resistance exercise increases blood volume but does not consistently improve orthostatic tolerance. 相似文献
42.
Platner JH Bennett LM Millikan R Barker MD 《Environmental and molecular mutagenesis》2002,39(2-3):102-107
The National Breast Cancer Coalition (NBCC) is a grassroots organization that represents breast cancer advocates and is committed to eradicating breast cancer. NBCC defines a breast cancer advocate as someone who has been personally affected by the disease (e.g., a breast cancer survivor, family member, or friend), represents a constituency, and is motivated to join the fight against the disease. One of the organization's goals is to ensure that breast cancer advocates have a seat at the table when decisions are made about breast cancer research and policy. To accomplish this goal, NBCC educates advocates so that they can participate in and make meaningful contributions to legislative, scientific, and regulatory decision-making bodies. In addition to creating educational opportunities for advocates, NBCC has spearheaded several initiatives designed to directly increase the quality and quantity of breast cancer research. NBCC has also played a major role in making funding available to breast cancer researchers. Two of NBCC's most notable programs include Project LEAD, an intensive science-training course for breast cancer advocates, and the Environmental Initiative, a collection of activities designed to improve research into the relationship between breast cancer and the environment. Breast cancer advocates trained by NBCC have partnered with the scientific community and individual scientists to improve the peer review, design, and implementation of breast cancer research. 相似文献
43.
Yoshitaka Iwasaki Judith Bartlett Kelly MacKay Jennifer Mactavish Janice Ristock 《Journal of community psychology》2008,36(6):702-722
This study reports key findings from a research project, which examined the stress and coping mechanisms of several nondominant groups of individuals. The groups were based in Winnipeg, Manitoba, Canada and included (a) Aboriginal individuals with diabetes, (b) individuals with disabilities, and (c) gays and lesbians. Our analyses of personal narratives and life stories have led to develop an interpretive map of findings that depicts mechanisms of how stress and coping operate. Specifically, the interpretive map consists of personal and structural stressors, meanings of stress, and personal and structural resources, as well as of two constructs termed intersectionality and social exclusion. Not only are nondominant voices and lived experiences recognized and incorporated into an emergent interpretive map, but this map also articulates the complex ways in which multiple identities intersect (i.e., intersectionality) and the realities of being excluded socioeconomically, culturally, and politically among nondominant groups (i.e., social exclusion). © 2008 Wiley Periodicals, Inc. 相似文献
44.
Distress and DNA repair in human lymphocytes 总被引:3,自引:0,他引:3
Janice K. Kiecolt-Glaser Ralph E. Stephens Philip D. Lipetz Carl E. Speicher Ronald Glaser 《Journal of behavioral medicine》1985,8(4):311-320
This research assessed differences in DNA repair in lymphocytes from high-and low-distressed individuals. A median split on Minnesota Multiphasic Personality Inventory (MMPI) Scale 2 divided 28 newly admitted nonpsychotic psychiatric inpatients into high- and low-distress subgroups. The high-distress subgroup had significantly poorer DNA repair in lymphocytes exposed to X-irradiation than low-distress subjects. We also found that lymphocytes obtained from this psychiatric sample had significantly poorer DNA repair than lymphocytes from nonpsychiatric control subjects when compared 5 hr after X-irradiation. A high level of distress therefore appears to be associated with significant dysfunctional differences at the molecular level which may have important implications for health. These data provide evidence for a direct pathway through which distress could influence the incidence of cancer.This research was funded in part by General Molecular Applications, Inc., the Bremer Foundation, the Samuel J. Roessler Fund, and Comprehensive Cancer Center Core Grant CA-16068-09. 相似文献
45.
Joyce PR Porter RJ Mulder RT Luty SE McKenzie JM Miller AL Kennedy MA 《Psychological medicine》2005,35(4):511-517
BACKGROUND: Although diurnal variation of mood is a widely recognized symptom of depression, the clinical, neurobiological and psychopharmacological significance of this symptom has not previously been reported. METHOD: A total of 195 depressed out-patients underwent a detailed clinical and neurobiological assessment, and were then randomized to treatment with either fluoxetine or nortriptyline. RESULTS: Of the 195 depressed patients, 62 had a pattern of reversed diurnal variation (i.e. worse in the evening). Those with reversed diurnal variation had a poorer response to a serotonergic anti-depressant, were less likely to have bipolar II disorder, had a higher tryptophan: large neutral amino acid ratio and had different allele frequencies of the polymorphisms in the promoter region of the serotonin transporter. CONCLUSIONS: These findings raise the possibility of serotonergic influence on diurnal variation, and that the symptom of reversed diurnal variation is of relevance to antidepressant prescribing. 相似文献
46.
Loudon JK Wiesner D Goist-Foley HL Asjes C Loudon KL 《Journal of Athletic Training》2002,37(3):256-261
OBJECTIVE: Patellofemoral pain syndrome (PFPS) is a common clinical entity seen by the sports medicine specialist. The ultimate goal of rehabilitation is to return the patient to the highest functional level in the most efficient manner. Therefore, it is necessary to assess the progress of patients with PFPS using reliable functional performance tests. Our purpose was to evaluate the intrarater reliability of 5 functional performance tests in patients with PFPS. DESIGN AND SETTING: We used a test-retest reliability design in a clinic setting. SUBJECTS: Two groups of subjects were studied: those with PFPS (n = 29) and those with no known knee condition (n = 11). The PFPS group included 19 women and 10 men with a mean age of 27.6 +/- 5.3 years, height of 169.80 +/- 10.5 cm, and weight of 69.59 +/- 15.8 kg. The normal group included 7 women and 4 men with a mean age of 30.3 +/- 5.2 years, height of 169.55 +/- 9.9 cm, and weight 69.42 +/- 14.6 kg. MEASUREMENTS: The reliability of 5 functional performance tests (anteromedial lunge, step-down, single-leg press, bilateral squat, balance and reach) was assessed in 15 subjects with PFPS. Secondly, the relationship of the 5 functional tests to pain was assessed in 29 PFPS subjects using Pearson product moment correlations. The limb symmetry index (LSI) was calculated in the 29 PFPS subjects and compared with the group of 11 normal subjects. RESULTS: The 5 functional tests proved to have fair to high intrarater reliability. Intrarater reliability coefficients (ICC 3,1) ranged from.79 to.94. For the PFPS subjects, a statistical difference existed between limbs for the anteromedial lunge, step-down, single-leg press, and balance and reach. All functional tests correlated significantly with pain except for the bilateral squat; values ranged from.39 to.73. The average LSI for the PFPS group was 85%, while the average LSI for the normal subjects was 97%. CONCLUSIONS: The 5 functional tests proved to have good intrarater reliability and were related to changes in pain. Future research is needed to examine interrater reliability, validity, and sensitivity of these clinical tests. 相似文献
47.
Autosome and Sex Chromosome Diversity Among the African Pygmy Mice, Subgenus Nannomys (Murinae; Mus)
Frédéric Veyrunes Josette Catalan Bruno Sicard Terence J. Robinson Jean-Marc Duplantier Laurent Granjon Gauthier Dobigny Janice Britton-Davidian 《Chromosome research》2004,12(4):369-382
The African pygmy mice, subgenus Nannomys, constitute the most speciose lineage of the genus Mus with 19 recognized species. Although morphologically very similar, they exhibit considerable chromosomal diversity which is here confirmed and extended by the G-banding analysis of 65 mice from West and South Africa. On the basis of their karyotype and distribution area, the specimens were assigned to at least five species. Extensive differentiation both within and between species was observed that involved almost exclusively Robertsonian translocations, 23 of which are newly described. Two of the rearrangements were sex chromosome-autosome translocations, associated in some cases with partial deletions of the X or Y chromosomes. Several authors have predicted that the highly deleterious effect of this rearrangement would be reduced if the sex and autosomal segments were insulated by a block of centromeric heterochromatin. The C-banding analyses performed showed that among the species carrying X-autosome translocations, one followed the expected pattern, while the other did not. In this case, functional isolation of the sex and autosome compartments must involve other repetitive sequences or genomic traits that require further molecular characterization. Such studies will provide insight into the causes and consequences of the high diversity of sex chromosome rearrangements in this subgenus. 相似文献
48.
Carlson EC Audette JL Veitenheimer NJ Risan JA Laturnus DI Epstein PN 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2003,271(2):332-341
Capillary basement membrane (CBM) thickening is an ultrastructural hallmark in diabetic patients and in animal models of diabetes. However, the wide variety of tissues sampled and diverse methods employed have made the interpretation of thickness data difficult. We showed previously that acellular glomerular BMs in OVE26 transgenic diabetic mice were thickened beyond normal age-related thickening, and in the current study we hypothesized that other microvascular BMs likewise would show increased widths relative to age-matched controls. Accordingly, a series of tissues, including skeletal and cardiac muscle, ocular retina and choriod, peripheral nerve, lung, pancreas, and renal glomerulus was collected from 300-350-day-old normal and transgenic mice. Transmission electron micrographs of cross sections through capillary walls were prepared, and CBM thickness (CBMT) was determined by the "orthogonal intercept" method. Morphometric analyses showed highly variable transgene-related BMT increases in the sampled tissues, with glomerular BM showing by far the greatest increase (+87%). Significant thickness increases were also seen in the retina, pulmonary alveolus, and thoracoabdominal diaphragm. BMT increases were not universal; however, most were modestly widened, and those that were thickest in controls generally showed the greatest increase. Although the pathogenesis of diabetes-related increases in CBM is poorly understood, data in the current study showed that in OVE26 transgenic mice increased BMT was a frequent concomitant of hyperglycemia. Accordingly, it seems likely that hyperglycemia-induced microvascular damage may be a contributing factor in diabetic BM disease, and that microvessel cellular and extracellular heterogeneity may limit the extent of CBM thickening in diverse tissues. 相似文献
49.
Antibodies to common ovine and bovine C-type virus specific antigen in serum from sheep with spontaneous leukosis and from inoculated animals 总被引:1,自引:0,他引:1
C-type virus containing preparations from concanavalin stimulated sheep lymphocyte culture fluids were treated with ether, and used for antigen in immunodiffusion tests. 13 out of 14 sera from sheep with spontaneous lymphatic leukosis showed precipitation reaction with the antigen preparation. 3 out of 33 sera from clinically unsuspect sheep in the same multiple case herd also formed precipitin bands. 3 out of 37 sera from offspring of leukotic ewes, 3 out of 9 sera from sheep, inoculated as newborne lambs with leukotic material, and 1 out of 4 sera from inoculated goats precipitated in the same manner. Immunodiffusion tests with a similar antigen preparation from bovine lymphocyte culture fluid led to strong identical results. 162 sera from sheep out of leukosis free herds did not show precipitation reactions. These findings seem to demonstrate the presence of antibodies to common ether resistent ovine and bovine C-type virus specific antigen. Our investigations show a clear correlation between clinical findings in sheep leukosis, demonstration of C-type particles in lymphocyte cultures, and antibody reactions. 相似文献
50.