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991.
Christian Humpel Marc Bygdeman Lars Olson Ingrid Strmberg 《The Journal of comparative neurology》1994,340(3):337-348
The human-to-rat xenograft approach offers possibilities to study aspects of primate cortex development and function without monkeys. Human fetal cortical tissue was grafted to prepared cortical cavities of immunosuppressed host rats. Fetal tissue fragments were collected after routine low-pressure vacuum aspiration abortions performed in the first trimester of gestation. Human derived neurons and human nerve fiber outgrowth were visualized by immunohistochemistry with antibodies against human neurofilament protein 70 kD (hNFP70). Ingrowth from rat host striatum or cortex into the grafts was analyzed by immunohistochemistry with antibodies against tyrosine hydroxylase. Astrocytes were evaluated by immunohistochemistry with antibodies against glial fibrillary acidic protein. The grafts grew into different sizes (1–10 mm in diameter) and contained large numbers of hNFP70-positive nerve fibers. All grafts gave rise to outgrowth of hNFP70-positive fibers into the host with partly a cortical layering; layers III and IV received a majority of the human fibers. In several cases, the graft-derived nerve fibers entered the host brain at restricted areas, while there was no crossing over of nerve fibers at the rest of the graft-host interface. Tyrosine hydroxylase-positive fibers were usually not abundant in the grafts. Interestingly, cases of massive ingrowth occurred from host striatum into the graft in a pattern suggesting “permissive sites” at the graft-host interface in the same way as outgrowth from graft to host was found. Additionally, tyrosine hydroxylase-immunoreactive fibers from host cortex were found to grow into the transplant. Glial fibrillary acidic protein immunoreactivity was increased at the interfaces between graft and host cortex or host striatum. Immunohistochemistry using antibodies against rat IgG indicated the presence of rat IgG within the grafts, and in bordering areas of host brain, possibly indicating a defective graft-host barrier. Taken together, these results show that human cortical-tissue pieces grafted to cortical cavities of immunosuppressed rats survive grafting and develop, and that reciprocal nerve fiber growth between grafts and hosts occur. Human cortical neurons can grow into the rat host brain in a pattern which is partly determined by host cortical architecture. © Wiley-Liss, Inc. 相似文献
992.
Gerry Larsson Bodil Wilde Larsson Ingrid M. E. Munck 《Scandinavian journal of caring sciences》1998,12(2):111-118
In 1994, the questionnaire ‘Quality of Care from the Patient's Perspective’ (QPP) was developed using a conventional factor analytical approach (Wilde et al. 1994). The items and conceptual framework of this questionnaire were derived from a theoretical model, which, in turn, was developed from qualitative patient interviews, using a grounded theory method of analysis (Wilde et al. 1993). The aims of this study were to develop further the dimensionality of the QPP using structural equation modelling combined with advances in factor analysis modelling, and to refine the instrument. This comparatively new methodology extracts more information out of questionnaire data and is considered to be superior to traditional scaling methods. The sample consisted of 611 somatic inpatients from four departments at a Swedish hospital. Data collected with the QPP were explored with the new tool tracing the dimensions postulated in the theoretical model underlying the QPP. A nested factor model was developed fulfilling statistical criteria for adjustment between model and data. The model consists of a general factor and 16 subordinate factors. Most of the original QPP scales were reproduced with the new statistical technique. However, some content changes were made which appear to bring the QPP scales closer to patients' meaning representations of the area. Some changes were also made to the response format, changes which appear to strengthen the psychometric properties of the instrument. The refined QPP will hopefully contribute to a more differentiated picture of quality of care when applied in the field. All scales, items, and response formats of the revised QPP are presented in an appendix. 相似文献
993.
PURPOSE: To investigate midlatency auditory evoked potentials (MLAEP) waveforms during recovery from anesthesia. The hypothesis was that MLAEP are sensitive variables to discriminate between states of consciousness and unconsciousness during emergence from anesthesia. METHODS: MLAEP were recorded in the awake state and during the wake-up phase from isoflurane anesthesia in 22 female patients undergoing ophthalmologic surgery. During emergence from anesthesia the changes in latency and amplitude of MLAEP components Na, Pa and Nb were compared with the awake level. The next day the patients were asked for explicit memory for the recovery period. RESULTS: In 72% of the patients the MLAEP waveforms were completely suppressed during isoflurane anesthesia. When the patients responded and opened their eyes spontaneously 38 +/- 12 min after anesthesia, the latencies of Na (18.3 +/- 1.2 vs 17.6 +/- 1.3; P = 0.013) and Nb (47.4 vs 7.1 vs 44.7 +/- 7.8; P = 0.048) remained prolonged compared with awake values. In contrast, the amplitudes NaPa and PaNb had regained baseline level. Nine patients had explicit memory for the immediate recovery period. However, there was no difference for any MLAEP component between patients with and without memory at any time. CONCLUSIONS: The persistent changes of MLAEP latency components Na and Nb indicated impaired auditory signal processing 38 min after isoflurane anesthesia. There was a marked intra- and inter-individual variability during reversal of the anesthetic induced MLAEP changes. This limits the prediction of recovery of consciousness in the individual patient during emergence from anesthesia. 相似文献
994.
Ingrid Grimmer Christoph Bührer Joachim W Dudenhausen Andrea Stroux Horst Reiher Horst Halle Michael Obladen 《BMC public health》2002,2(1):10-8
Background
Very low birthweight, i.e. a birthweight < 1500 g, is among the strongest determinants of infant mortality and childhood morbidity. To develop primary prevention approaches to VLBW birth and its sequelae, information is needed on the causes of preterm birth, their personal and social antecedents, and on conditions associated with very low birthweight. Despite the growing body of evidence linking sociodemographic variables with preterm delivery, little is known as to how this may be extrapolated to the risk of very low birthweight. 相似文献995.
Audina M. Berrocal Ingrid U. Scott Darlene Miller Harry W. Flynn 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2002,240(4):329-330
PURPOSE: To report the clinical presentation, antibiotic sensitivities, and treatment outcomes of endophthalmitis caused by Moraxella osloensis. METHODS: Case series: retrospective review of the medical records of all patients treated for endophthalmitis at Bascom Palmer Eye Institute between 1 January 1991 and 31 December 2000. RESULTS: During the study interval, 757 eyes were treated for endophthalmitis. Moraxella osloensis was isolated from three eyes of two patients (3/757, or 0.39%). In all three eyes, the endophthalmitis was delayed-onset and bleb-associated; Moraxella osloensis was isolated on chocolate agar and 5% sheep's blood agar using a RapNH commercial Kit (by Remel) through an automated system (Vitek). Like most gram-negative organisms, Moraxella was sensitive to ceftazidime, ciprofloxacin, and the aminoglycosides. Although vision at presentation was poor, both patients regained baseline vision after treatment with pars plana vitrectomy and injection of intravitreal antibiotics. CONCLUSIONS: To our knowledge, this is the first report of endophthalmitis caused by Moraxella osloensis. Unlike most series of delayed-onset, bleb-associated endophthalmitis the visual prognosis following treatment for endophthalmitis caused by Moraxella osloensis appears to be generally favorable. 相似文献
996.
Anselm J Deninger Sven M?nsson J Stefan Petersson G?ran Pettersson Peter Magnusson Jonas Svensson Bj?rn Fridlund Georg Hansson Ingrid Erjefeldt Per Wollmer Klaes Golman 《Magnetic resonance in medicine》2002,48(2):223-232
A new strategy for a quantitative measurement of regional pulmonary ventilation using hyperpolarized helium-3 (3He) MRI has been developed. The method employs the build-up of the signal intensity after a variable number of (3)He breaths. A mathematical model of the signal dynamics is presented, from which the local ventilation, defined as the fraction of gas exchanged per breath within a given volume, is calculated. The model was used to create ventilation maps of coronal slices of guinea pig lungs. Ventilation values very close to 1 were found in the trachea and the major airways. In the lung parenchyma, regions adjacent to the hilum showed values of 0.6-0.8, whereas 0.2-0.4 was measured in peripheral regions. Monte Carlo simulations were used to investigate the accuracy of the method and its limitations. The simulations revealed that, at presently attainable signal-to-noise ratios, the ventilation parameter can be determined with a relative uncertainty of <5% over a wide range of values. 相似文献
997.
998.
A. Grassegger Ingrid Rollinger-Holzinger Bernhard W. H. Zelger Kurt Heim Heinz Zwierzina Peter O. Fritsch Reinhard M. Höpfl 《Archives of dermatological research》1997,289(5):243-250
The purpose of the study was to investigate the cytokine gene expression patterns and immunohistochemical characteristics
of genitoanal warts in order to obtain a clue as to the immunological mechanisms possibly relevant for wart regression or
persistence. We analysed surgically removed warts from 11 patients, 2 of whom were immunosuppressed. Lesions of five of the
nine otherwise healthy individuals were additionally treated with intralesional interferon-γ (IFNγ) prior to surgery. Invasion
of CD4
+
T cells into the papillomas and HLA-DR and ICAM-1 expression on keratinocytes were found in two otherwise healthy patients
and were intensified by intralesional IFNγ in four of five patients. The mRNA expression patterns in seven of eight nonrecurrent
warts were compatible with a predominant TH1 or mixed TH1/TH2 cytokine profile. In contrast, in recalcitrant warts of three
patients (one healthy, two immunocompromised) histological signs of immunoreactivity and TH1-like cytokine mRNA expression
were not detected. In recurrent warts of a renal transplant patient, IL-4 and IL-5 mRNA expression was repeatedly found suggesting
a predominant TH2 response. In conclusion, immunoreactivity to genitoanal warts such as T-cell infiltration, HLA-DR and ICAM-1
expression was associated with a predominant TH1 or mixed TH1/ TH2 cytokine mRNA expression profile.
Received: 5 August 1996 相似文献
999.
Herbert Niels Flach Ingrid Grassert Günther Oehme 《Macromolecular chemistry and physics.》1994,195(10):3289-3301
The synthesis of new types of soluble and insoluble amphiphilic systems is described, being polysoaps, crosslinked polysoaps, an amphiphilised ion exchanger, and ion exchangers loaded with ionic surfactants. It was possible to synthesise insoluble polymeric systems which nevertheless showed micellar properties. The polymers were tested as aids in the stereospecific hydrogenation of (Z)-methyl α-acetamidocinnamate to the methyl ester of N-acetylphenylalanine (R) by means of an optically active rhodium complex in water. With linear polysoaps the effect on the reaction was dependent on the structure of the soap molecules. The enantioselectivity of the reaction with monomeric surfactants in water was almost attained. Crosslinked polysoaps showed the same effects on the hydrogenation as linear polysoaps with an analogous structure. Macromolecular ion exchangers loaded with amphiphilic counterions gave in hydrogenation almost the same effect as these counterions give when they are not bound to an insoluble carrier. Enantioselectivities and reaction rates were usually slightly lower than with monomeric surfactants. However, there is an advantage in the separation of catalyst and product after reaction. It was shown that the rhodium-containing amphiphilic ion exchangers could be reused for up to 9 times. 相似文献
1000.