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91.
Emotion-modulated startle is a robust phenomenon that has been demonstrated in a wide range of experimental situations. Similarly, heart rate variability (HRV) has been associated with a diverse range of processes including affective and attentional regulation. The present study sought to examine the relationship between these two important measures of affective behavior. Ninety female participants viewed pleasant, neutral, and unpleasant pictures while exposed to acoustic startle stimuli. The eyeblink startle was recorded both during the affective foregrounds and during intertrial intervals. HRV was assessed during a resting baseline and relationships between HRV and startle magnitudes examined. Results indicated that resting HRV was inversely related to startle magnitude during both intertrial intervals and affective foregrounds. In addition, the participants with the highest HRV showed the most differentiated emotion-modulated startle effects, whereas those with the lowest HRV, compared to those with the highest HRV, showed significantly potentiated startle to neutral foregrounds and marginally potentiated startle to pleasant foregrounds. The findings are consistent with models that posit that prefrontal cortical activity modulates subcortical motivation circuits. These results have important implications for the use of startle probe methodology and for HRV in the study of emotional regulation and dysregulation.  相似文献   
92.
Background: This paper is part of a prospective, epidemiologic study concerning postpartum depression (PPD). The women were first examined during pregnancy; after delivery they were seen with their infants at 3 and 18 months. The present study focuses on the 3-months-postpartum results. Methods: A sample of 570 women and their infants were examined 3 months after delivery. Using the EPDS (Edinburgh Postnatal Depression Scale; Cox et al., 1987. Br. J. Psychiatry 150:782–786), 10.2% of these new mothers presented PPD. The focus of the study concerned the effects of this neurotic disorder on the mother, the infant and on the mother–infant relationship. Results: The deleterious effects concerning the infant were functional disorders such as eating or sleeping difficulties. The ‘depressed’ dyads presented less vocal and visual communications, less corporal interactions and less smiling. Conditions surrounding delivery and tiredness at 3 months are linked to difficulties in mother–infant relationship for the non-depressed mothers. Logistic models showed that primiparous PPD mothers have difficulties bathing their infants, whereas multiparous PPD mothers are more tired. Limitation: This study did not take into account either protective factors or the effects of the infant himself. Clinical relevance: Knowledge of the mothers’ and infants’ difficulties may help caregivers to detect these at-risk dyads and initiate therapeutic measures.  相似文献   
93.
Ohne ZusammenfassungBenutzte Symbole und Abkürzungen NNR Nebennierenrinde - DOCA Desoxycorticosteronacetat - K i intracelluläres Kalium (sinngemäß für Natrium) - K a extracelluläres Kalium (sinngemäß für Natrium) - Q Ladung - E m Membranruhepotential - m Zeitkonstante der Membran - R m Membranwiderstand - C m Membrankapazität  相似文献   
94.
BACKGROUND: Enteroviruses (EV) and parechoviruses (HPeV) are the most common causes of aseptic meningitis, encephalitis and sepsis-like syndrome in neonates. Detection by nucleic acid amplification methods improves patient management. OBJECTIVE: Development of a real-time PCR assay on a LightCycler for simultaneous detection of EV, HPeV and an internal control to monitor inhibition. STUDY DESIGN: We investigated the value of the new assay, prospectively, in a variety of samples from patients suspected of having viral meningitis or sepsis-like syndrome. RESULTS: The assay detected 64 EV serotypes and HPeV types 1-4. Of 186 patients, 63 (33.9%) were EV positive and 18 (9.7%) HPeV positive in one or more samples. In 43 of 159 feces and 6 of 57 throat samples viral culture and PCR were positive. With real-time PCR 27 extra EV and 19 HPeV positives were found. Blood and CSF were present from 33 patients. In 19 patients blood and CSF were positive, one was only positive in CSF, two were only positive in blood, 11 were negative. From 96 patients CSF and/or blood samples were tested and compared to results in throat and/or feces samples. Forty patients were EV-PCR and 14 HPeV-PCR positive in blood and/or CSF. All of these were confirmed by a positive PCR for the respective virus in feces and/or throat. CONCLUSIONS: Simultaneous detection of EV and HPeV with this two-step real-time PCR is specific, faster and more sensitive than viral culture. All systemic infections (blood or CSF positive) were confirmed in feces. Culture is no longer necessary for clinical diagnosis and should only be performed on PCR-positive samples to obtain isolates for typing purposes. Application of this assay is an important improvement for patient management since the outcome of the analysis is available within the time frame of clinical decision-making.  相似文献   
95.
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97.
The long arm of chromosome 11 is one of the most interesting regions in the search for major genes involved in the etiology of manic-depressive illness. Several candidate genes have been identified, including the gene encoding the dopamine D2 receptor, the M1 muscarinic receptor, and porfobillinogen deaminase. Furthermore, different families with co-segregation of psychiatric illness and structural chromosome abnormalities involving regions 11q21, 11q22.3, and 11q25 have been reported. Using narrow as well as broad phenotypic models, conservative genetic parameters, models with dominant or recessive modes of inheritance, and various methods to reduce misclassification, the present study did not find evidence for a major gene causing manic-depressive illness on the long arm of chromosome 11. In the broader phenotypic models multi-point analyses excluded at least 11q14 to 11q23.3, approximately 60 cM, even in one large family. Assuming homogeneity close linkage to DRD2 was excluded for all dominant models, and also in the affecteds-only analyses in the large family alone. © 1995 Wiley-Liss, Inc.  相似文献   
98.
Zusammenfassung Über einen Zeitraum von 8 bis 12 Monaten wurden 1 Patient mit primärer und 2 Patienten mit sekundärer Osteoporose bei Osteogenesis imperfecta mit hochgereinigtem Wachstumshormon aus menschlichen Hypophysen behandelt. Aus den Ergebnissen der laborchemischen, knochenhistologischen und kinetischen Untersuchungen mit47Calcium vor und nach der Therapie ließ sich kein positiver Effekt auf die Knochenerkrankung ermitteln. Dies steht im Gegensatz zu tierexperimentellen Untersuchungen an ausgewachsenen Hunden, bei denen es bereits 3 Monate nach Beginn der Applikation von Wachstumshormon zu einer Positivierung der Knochenbilanz gekommen war.  相似文献   
99.
Zusammenfassung Unter chronischer Hämodialyse-Behandlung wurden 13 Fälle auf Knochenveränderungen unter Berücksichtigung des Calcium-Phosphat-Stoffwechsels untersucht. Die Knochenveränderungen wurden histomorphometrisch definiert. Bestimmt wurden die prozentualen Anteile der neutralen Oberflächen, des Osteoids, der aktivierten Osteoblasten, der Resorptionslacunen und der mehrkernigen Osteoclasten an den endostalen Oberflächen, sowie die mittlere Breite der Osteoidsäume. Außerdem wurden Formation und Resorption des Knochens mittels quantitativer Mikroradiographie sowie die volumetrische Dichte der Spongiosa gemessen.Beiallen Fällen konnten unterschiedlich schwere Knochenveränderungen nachgewiesen werden (60% schwere und 40% leichte), wobei die stets pathologisch erhöhte Knochenresorption als Ausdruck eines regulativen sekundären Hyperparathyreoidismus gewertet wurde. Eine direkte Beziehung zwischen Calciumspiegel und Schwere der renalen Osteopathie ließ sich nicht beweisen. Die Hyperphosphatämien, die bei allen Patienten unter der Hämodialyse-Behandlung unverändert blieben, ergaben mit den ansteigenden Serumcalciumwerten pathologische Calciumphosphatprodukte. Bei einem Teil der Patienten kam es zu extraossären Verkalkungen, die unter kontrollierter Behandlung mit Aluminiumhydroxyd und abfallendem Calciumphosphatprodukt eine erhebliche Rückbildungstendenz zeigten. Wegen der Gefahr derartiger Calcifizierungen verbot sich in unserem Krankengut eine Vitamin D-Behandlung. Die Indikation einer totalen oder subtotalen Parathyroidektomie wurde in Abhängigkeit vom Ausmaß der Osteopathie und einer möglichen Nierentransplantation erörtert.
Bone Disease and Calcium-phosphate Metabolism in Chronic Hemodialysis
Summary 13 patients under chronic hemodialysis were studied for changes in the bone, whereby calcium and phosphorus metabolism were given special attention. The changes in the bone were defined histomorphometrically. The percentage of the neutral surfaces, the osteoid, the activated osteoblasts, the resorption lacunae and the polynuclear osteoclasts of the endosteal surfaces were determined as well as the medium width of the osteoid seams. Moreover, formation and resorption of the bone were assessed by quantitative microradiography and the volumetric density of the cancellous bone was measured. Inall cases, bone changes of various degree were observed (60% of serious and 40% of slight changes), whereby the constantly increased bone resorption was considered as expression of a regulative secondary hyperparathyroidism. A direct relationship between serum calcium levels and the degree of seriousness of renal osteopathy could not be established. Hyperphosphatemia remained unchanged and with increasing serum calcium levels, the calcium phosphorus product became abnormally high in all subjects under hemodialysis. Extraosseus calcifications developed in some cases and were reduced to a considerable degree by controlled treatment with aluminiumhydroxide in connection with a fall of the calcium phosphorus product. Because of the risk of such calcifications, vitamin D treatment were out of question. Total or subtotal parathyroidectomy was discussed in relation to the degree of osteopathy and the possibility of a kidney transplantation.


Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.  相似文献   
100.
Interleukin-4 (IL-4) plays a major role in immunoglobulin E (IgE) production. Its signal is conferred to effector cells through binding to the alpha chain of the IL-4 receptor (IL-4Ralpha). We present further evidence for polymorphisms in the IL-4Ralpha gene having an effect on IgE regulation. For two of four common polymorphisms, S503P and Q576R, we found an association with lowered total IgE concentrations (P=0.0008 if occurring together). The polymorphism S503P has not yet been described and is located within the I4R motif of the receptor. In vitro analyses using synthetic peptides of this region showed that the tyrosine kinase Janus kinase 1 (JAK1), as well as IRS-1 and IRS-2 bind to the I4R motif irrespective of the polymorphism or a tyrosine phosphorylation. In vivo immunoassays using T cells of four different groups of individuals (S503/Q576; P503/Q576; S503/R576; P503/R576) revealed that only in case of both polymorphisms the phosphorylation of IRS-1 and IRS-2, but not JAK1 was increased. We found no binding of STAT6 to the I4R synthetic peptides; however, the phosphorylation was reduced in the presence of any of the two polymorphisms, including P503 alone. We discuss possible conformational changes of the receptor leading to the observed effects on the phosphorylation status of IRS-1, IRS-2 and STAT6, in addition to previous findings that Q576R alters STAT6 binding. We conclude that P503 and R576 influence the signal transduction pathways through the IL-4Ralpha, an effect that is magnified by the presence of both polymorphisms. This could explain the observed association effects with lowered total IgE concentrations.  相似文献   
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