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101.
Although nausea and vomiting are diagnostic migraine symptoms, most patients can take tablets by mouth and a few say they can eat some food. This study was conducted to determine the proportion who could eat or drink, what was consumable and with what effect. One-hundred-and-nine migraineurs were asked what they could eat or drink at the beginning or height of their attacks; 59 could not take any food by mouth, but 50 could eat during the headache phase of their migraine attacks. Four ate normally, 5 took smaller amounts of their normal dietary intake, and 3 took lighter meals. Dry, carbohydrate foods were consumable by the remaining 38: a few had specific cravings, most stated the precise variety which, when eaten, reduced nausea, headache, other symptoms or length of attacks. Patients should therefore be encouraged to eat what they can tolerate, with their tablets taken as early as possible after the onset of attacks. Simultaneous nausea, tolerance or even craving for specific foods occur in other conditions, particularly high altitude headaches which share other features of migraine attacks. The observations in this paper support the notion that migraine is a central neuronal metabolic disturbance.  相似文献   
102.
High mol. wt genomic DNA from a genetically dominant aryl hydrocarbonhydroxylase (AHH)-deficient mutant cell line derived from themouse hepatoma cell line Hepa-1 was used to transfect the parentcell line. AHH-deficient transfectants were recovered followingsingle-step selection in medium containing the carcinogen benzo(a)pyrene.The transfectants arose at a frequency of 2 x 10–7. Thisfrequency was at least 4-fold greater than the frequency ofspontaneous forward mutation in this cell line. In another setof experiments, dominant mutant DNA was co-transfected alongwith the selectable plasmid pSV2ecogpt into parental Hepa-1cells. The frequency of co-transfection was determined to be3 x 10–8. This frequency was 150 times greater than thatexpected on the basis of coincident but unrelated spontaneousmutation and plasmid uptake. Both types of transfectants werejudged, following somatic cell hybridizations, to possess thedominant phenotype of the mutant cell line, demonstrating thata trans-acting dominant negative regulator of AHH was transferredin these experiments. DNA transfection should therefore providea means for the molecular cloning of the gene that encodes thedominant regulator.  相似文献   
103.
Abstract Current research has provided evidence that nearly 90 percent of all cancers may be related to diet, environment, and lifestyle. Of this number, 30 to 40 percent of cancers in men and up to 60 percent of cancers in women may be related to diet and nutrition. The two-stage process in the formation of many cancers, defined as initiation and promotion, is influenced by many dietary components. Vitamins C, E, and the mineral selenium are nutrients that function as antioxidants, reducing potential cancer-causing chemicals in the body. These natural anticarcinogens are thought to alter the cancer process and are currently under study for their cancer prevention properties. The functions, Recommended Dietary Allowances, food sources, research evidence for cancer prevention, and recommendations for supplementation are presented for these three nutrients. Research suggests that the proper and prudent use of nutrients, along with a healthy diet and lifestyle, may offer protection against this devastating disease.  相似文献   
104.
Right-hand superiority for throwing but not for intercepting   总被引:2,自引:0,他引:2  
N V Watson  D Kimura 《Neuropsychologia》1989,27(11-12):1399-1414
In humans, the organization of movements performed by both upper limbs, relies significantly on a left hemisphere "praxis" system that also subsumes speech function. Right hand preference may also be an expression of this left hemisphere dependence, arising from the preferential connections of the right hand to the left hemisphere. Consequently, a manual task that maximizes the spatial complexity of a target (presumably engaging right hemisphere mechanisms), while concurrently minimizing motor-programming demands, was expected to yield a diminished disparity in preference and performance between the hands. Left and right hand accuracy were measured independently for two motor tasks in 48 normal right-handed university students. In the first task, darts were thrown overhand at a stationary target. For the second task, subjects were asked to use the open hand to block (but not catch) projectiles launched at varying trajectories and velocities. ANOVA yielded a significant Hand x Task interaction, in which the left hand did not differ from the right hand in intercepting ability, but was significantly less accurate than the right hand for throwing. A sex difference favouring males was found for both tasks; this difference was not reducible to differences in physique or athleticism.  相似文献   
105.
Use of seclusion and restraint on three inpatient adolescent psychiatric units was examined during two five-month periods before and after implementation of a "therapeutic management" protocol. Under the protocol, staff classified disruptive behaviors into four stages and provided verbal and behavioral interventions to control behavior at each stage. Patients who required seclusion and restraint had significant latitude to determine the timing of their release from the interventions and met with staff one hour and 24 hours after their release to explore alternatives to aggression. The number of episodes of seclusion and restraint fell by 64 percent after the protocol was adopted, and the number of patients who required those interventions dropped by 39 percent. The mean duration of episodes of seclusion and restraint was reduced by 59 percent. Therapeutic management provides a corrective experience by addressing the developmental needs, deficient cognitive skills, and poor internalized controls of disruptive adolescents.  相似文献   
106.
Corneal grafts are believed to enjoy a degree of "immunological privilege" primarily due to the avascularity of the recipient bed. In this study orthotopic full-thickness corneal grafts were carried out in the inbred rat, using a technique that is a close model of corneal grafting in humans. The survival times of corneal grafts on nonvascularized beds of 28 fully allogeneic strain combinations were determined without the use of immunosuppression. Some combinations were rejected rapidly, e.g. DA (RT1a) into BN (RT1n) with a mean survival time (MST) +/- SD of 7.8 +/- 1.3 days, and some at a moderate rate, e.g. AO (RT1u) into LEW (RT1l) with an MST of 23.1 +/- 10.0 days, whereas in other cases survival was indefinite, e.g. WAG (RT1u) into PVG (RT1c), an MST of greater than 100 days. Orthotopic corneal grafts on nonvascularized beds between DA and AO parents and the F1, followed the basic rules of transplantation genetics. In addition, the rate of graft rejection was significantly faster (P less than 0.001) with corneal grafts from DA into AO placed onto a vascularized compared with a nonvascularized corneal bed (MST of 6.8 +/- 2.4 or 12.1 +/- 4.0 days respectively). The rate of rejection of corneas on a vascularized bed was at a similar rate to that of orthotopic skin or heterotopic auxiliary heart grafts. The results indicate that the fate of a corneal allograft on a nonvascularized bed is dependent upon the particular combination of donor and recipient strain. No consistent association was observed between any donor or recipient RT1 haplotype and survival; this suggests that non-RT1 background genes may play a role in the survival of corneal grafts.  相似文献   
107.
M Watson 《Int J Health Serv》1989,19(3):443-456
In this article, the author describes the recent changes in patterns of drug use in Poland in the light of available data. A much higher incidence of use has been seen in the 1980s, and there are indications that this can be accounted for by increased use among young people from the manual working class. Social deprivation may play a part in the etiology of the 1980s "epidemic," and evidence is put forward in support of this view. Both patterns of use and the policies that have been introduced to deal with them are viewed in terms of the political, economic, and social context of post-Solidarity perestroika.  相似文献   
108.
The authors report four cases of fat embolism syndrome following total hip arthroplasty using cementless acetabular press-fit components and cemented press-fit femoral components. Factors implicated in the production of this syndrome following "hybrid" total hip arthroplasty include increased canal pressure during femoral reaming and prosthetic insertion, retained marrow elements and reaming debris, and the use of lumbar epidural anesthesia. This potentially fatal syndrome must be a recognized complication following the use of cemented press-fit femoral stems. Specific recommendations for decreasing the incidence of this complication are reviewed.  相似文献   
109.
To assess DNA immunization as a strategy for protecting against HIV infection in humans, we utilized SIVmne infection of Macaca fascicularis as a vaccine challenge model with moderate pathogenic potential. We compared the efficacy of DNA immunization alone and in combination with subunit protein boosts. All of the structural and regulatory genes of SIVmne clone 8 were cloned into mammalian expression vectors under the control of the CMV IE-1 promoter. Eight M. fascicularis were immunized twice with 3 mg of plasmid DNA divided between two sites; intramuscular and intradermal. Four primed macaques received a further two DNA immunizations at weeks 16-36, while the second group of four were boosted with 250 microg recombinant gp160 plus 250 microg recombinant Gag-Pol particles formulated in MF-59 adjuvant. Half of the controls received four immunizations of vector DNA; half received two vector DNA and two adjuvant immunizations. As expected, humoral immune responses were stronger in the macaques receiving subunit boosts, but responses were sustained in both groups. Significant neutralizing antibody titers to SIVmne were detected in one of the subunit-boosted animals and in none of the DNA-only animals prior to challenge. T-cell proliferative responses to gp160 and to Gag were detected in all immunized animals after three immunizations, and these responses increased after four immunizations. Cytokine profiles in PHA-stimulated PBMC taken on the day of challenge showed trends toward Thl responses in 2/4 macaques in the DNA vaccinated group and in 1/4 of the DNA plus subunit vaccinated macaques; Th2 responses in 3/4 DNA plus subunit-immunized macaques; and Th0 responses in 4/4 controls. In bulk CTL culture, SIV specific lysis was low or undetectable, even after four immunizations. However, stable SIV Gag-Pol- and env-specific T-cell clones (CD3+ CD8+) were isolated after only two DNA immunizations, and Gag-Pol- and Nef-specific CTL lines were isolated on the day of challenge. All animals were challenged at week 38 with SIVmne uncloned stock by the intrarectal route. Based on antibody anamnestic responses (western, ELISA, and neutralizing antibodies) and virus detection methods (co-culture of PBMC and LNMC, nested set PCR- of DNA from PBMC and LNMC, and plasma QC-PCR), there were major differences between the groups in the challenge outcome. Surprisingly, sustained low virus loads were observed only in the DNA group, suggesting that four immunizations with DNA only elicited more effective immune responses than two DNA primes combined with two protein boosts. Multigenic DNA vaccines such as these, bearing all structural and regulatory genes, show significant promise and may be a safe alternative to live-attenuated vaccines.  相似文献   
110.
Cytogenetic studies on fetal blood cells obtained at 18–25 weeks gestation have provided information for decision making in 25 cases identified as being at high risk of having an abnormal fetus. In particular, in the 21 cases studied to consider the possibility of true mosaicism, confirmation in fetal blood was obtained in three, one of which presented as a pseudomosaic on the original amniotic fluid cell study. Fetal blood was also informative in two cases (one positive and the other negative) in which a diagnosis of the fragile X syndrome was being considered. Furthermore, when high risk pregnancies presented late in gestation (21–24 weeks), these methods allowed for a rapid cytogenetic diagnosis. The procedure has proved useful in most of these cases since the couples involved had indicated that they would probably have terminated the pregnancy without the reassurance of normal fetal lymphocyte studies. Since the technique carries a much higher risk of pregnancy loss than does amniocentesis, its use should only be considered when there are compelling indications.  相似文献   
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