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The performance of a lateral-flow immunoassay, the QuickVue Influenza Test, for detection of influenza A and B viruses in comparison with that of cell culture was evaluated by using nasopharyngeal aspirates, in viral transport medium, from children with respiratory tract infections. The sensitivity and specificity were 79.2 and 82.6%, respectively.  相似文献   
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Sleep apnea syndrome and systemic hypertension are frequently associated but their causal relationship is unclear. We compared the oscillations of systemic blood pressure and heart rate during polysomnography in 8 normotensive subjects (2 females) and 5 hypertensive (supine awake blood pressure: 165 +/- 7/96 +/- 5 mmHg) without treatment. Their ages (normotensive: 52.1 +/- 11.0 yrs, hypertensive: 51.2 +/- 6.4 yrs) and body mass indices (32.6 +/- 9.6 kg/m2 vs 33.2 +/- 5.2 kg/m2 respectively) were not statistically different. Systemic blood pressure was continuously monitored by a non invasive digital plethysmography (Finapres). Both groups had similar respiratory events indices (normotensive: 45.2 +/- 18.1/hr, hypertensive: 48.4 +/- 20.5/hr) and minimal oxygen saturations (79.4 +/- 9.1% vs 82.4 +/- 7.0% respectively). During apneas in slow-wave sleep were observed the minimal values for systolic and diastolic pressures which were significantly higher in hypertensive than in normotensive (138.2 +/- 9.6/83.2 +/- 16.1 mmHg vs 105.9 +/- 11.1/60.5 +/- 10.9 mmHg respectively). During resumption of ventilation maximal blood values were recorded which were also higher in hypertensive than in normotensive (185.0 +/- 13.8/113.2 +/- 21.5 mmHg vs 155.9 +/- 19.8/88.7 +/- 17.1 mmHg respectively) (p less than 0.05). Although absolute variations of blood pressure were similar, relative changes in systolic pressure were significantly higher in normotensive (p less than 0.05). Maximal heart rate was 76.8 +/- 6.2 bpm in normotensive and 76.6 +/- 3.9 bpm in hypertensive during resumption of ventilation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The ability to transfer the dystrophin gene stably to the skeletal muscle of DMD patients is a major confounding issue in establishing an effective gene therapy for this disease. To overcome this problem, we have examined the ability of muscle fibres from mdx mice to act as in situ factories of retroviral vector production. Tibialis anterior (TA) muscles from 4-week-old mdx mice were injected with an adenoviral vector expressing LacZ within a retroviral expression cassette (AdLZIN). Retroviral vector production was induced by the inclusion of two additional adenoviral vectors expressing retroviral gag-pol (AdGagPol) and 10A1 env genes (Ad10A1). Upon introduction of infected muscles into cell culture, colonies of beta-galactosidase-expressing myotubes formed only in cultures where the muscle was injected with AdLZIN, AdGagPol and Ad10A1, but not from muscle injected with AdLZIN only. Muscles from mdx/nude mice producing retroviral vector displayed a 4.6-fold increase in beta-galactosidase-positive myofibres after 1 month, compared with contralateral muscle in the same animal injected with AdLZIN and AdGagPol only. By constructing a hybrid adeno-retroviral vector expressing a truncated micro-dystrophin construct (AdmicroDyIN), we were able to partially correct the mdx dystrophic phenotype. AdmicroDyIN-mediated expression of micro-dystrophin in mdx TA muscle restored the formation of the dystrophin-associated glycoprotein complex and significantly reduced the level of muscle degeneration over uninjected controls. By stimulating in situ production of retroviral vector expressing micro-dystrophin, we achieved 92%+/-6% transduction of myofibres in the TA muscle by 4 weeks. Strikingly, by 3 months post injection, micro-dystrophin was still expressed to high levels in nearly all the myofibres of the TA muscle. By comparison, there was a pronounced drop in the levels of micro-dystrophin expressed by muscles injected with AdmicroDyIN only. Finally, using a novel PCR approach, we detected reverse-transcribed, integrated proviral sequences in TA muscle genomic DNA by 4 weeks post injection, the levels of which were found to increase after 3 months.  相似文献   
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Summary The ATPase activity of scallop (Pecten maximus) striated adductor myosin and heavy meromyosin (HMM) have been investigated as a function of [Ca2+] using formycin triphosphate (FTP) as a fluorescent ATP analogue. The FTPase activity of the regulated fraction of these preparations was activated steeply over the range of 0.1 to 1M [Ca2+ ], implying the existence of a form of cooperativity that is intrinsic to the myosin heads. In addition to the previously characterised heterogeneity with respect to an unregulated fraction, the regulated fraction of HMM was resolved into two populations whose activities showed a slightly different dependency on [Ca2+ ]. This was revealed unambiguously at intermediate levels of activation where, in some experiments, the product release rate constants differed for the two populations by more than fivefold. At maximum relaxation or maximum activation, these rate constants differed by two-to three-fold and were not clearly resolved by the multiexponential fitting procedure. The populations might arise as a consequence of isoenzymes, modification during preparation or slowly interconverting conformers; Ca2+ binding itself being a rapid equilibrium process in both populations. FTP turnover by myosin could not be analysed in such detail because of the technical problems of measuring the fluorescence of a suspension of filaments, but the rates of the elementary steps appeared similar to those of HMM. The fraction of unregulated molecules in myosin preparations was comparable to that of HMM indicating that if it is a consequence of preparative damage, the modification must occur prior to tryptic digestion.  相似文献   
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To assess the performance of continuous positive airway pressure devices in treatment of sleep breathing disorders during polysomnographic studies, analysis are based essentially on the patient airflow signal measured by a pneumotachograph and the mask pressure. These signals used either by the softwares or the physicians provide powerful information on respiratory events occurring during the night. However, sometimes signals are artifacted by airflow leaks at the mask or the mouth. These artifacts are causes of information loss and then of possible wrong interpretations. We studied the relationship between airflow and mask pressure at the occurrence of leaks. We used analogy with electrical models and Kirchoff laws to estimate mask leaks and to detect mouth breathing. A Starling model connected to a flow generator simulated respiratory movements. A positive pressure was maintained in the model and artificial leaks comparable to mask leaks were provoked. Then, we replaced the Starling model and the flow generator by two healthy volunteers. We computed mask leaks in both conditions and found no contradiction between the simulated model and the subjects. Equations of the analog circuit were helpful to assess mask leaks and to detect mouth breathing. Such equations could be included in polysomnographs or in pressure generator algorithms either for detecting leaks or adjusting airway pressure.  相似文献   
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The cysteine proteinases CPA and CPB from Leishmania major induced Th1 responses in patients with leishmaniasis due to Leishmania guyanensis. Furthermore, cysteine proteinases induced neither interleukin 4 (IL-4) nor IL-13 and low levels of IL-10 in controls and patients. The results suggest that CPs would be quite good candidates for a vaccine against different Leishmania species.  相似文献   
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Loss of RhoB expression in human lung cancer progression.   总被引:6,自引:0,他引:6  
PURPOSE: RhoB is a low molecular weight GTPase belonging to the Ras protein superfamily. Whereas most Rho proteins have been shown to have a positive role in proliferation and malignant transformation, the specific role of RhoB appears more divergent. We reported previously that RhoB inhibits cell proliferation in various human cancer cells. Here, we studied the specific role played by RhoB in human lung cancer. EXPERIMENTAL DESIGN: We analyzed the expression of RhoB protein by immunostaining in human lung tissues ranging from normal to invasive carcinoma from different histological types in two large independent studies of, respectively, 94 and 45 samples. We then studied the cellular effect of RhoB overexpression in a model of lung cancer (A549, adenocarcinoma) and tumorigenicity in nude mice. RESULTS: We showed in both studies that RhoB protein was expressed in normal lung and decreased dramatically through lung cancer progression (P < 0.01). Interestingly, RhoB expression was lost in 96% of invasive tumors and reduced by 86% in poorly differentiated tumors compared with the nonneoplastic epithelium. Moreover, the loss of expression of RhoB correlated significantly with tumor stage and proliferative index, whereas no correlation was found between RhoB and p53 or Bcl-2 expression. We then showed that ectopic expression of RhoB in lung cancer cell line A549 suppressed cell proliferation, anchorage-independent growth, and xenograft tumor growth in nude mice. CONCLUSIONS: RhoB loss of expression occurs very frequently in lung carcinogenesis, reinforcing its putative tumor suppressive activity, and raising the value of its potential use in cancer therapy.  相似文献   
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