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BACKGROUND AND OBJECTIVES: An eight-member group consisting of Canadian infectious disease and immunology specialists and a family physician with significant experience in HIV management was convened to update existing recommendations, specifically intended for use by Canadian HIV-treating physicians, on the appropriate use of enfuvirtide in HIV/AIDS patients with resistance to other antiretroviral drugs. METHODS: Evidence from the literature and expert opinions of the group members formed the basis of the guidelines. Comments on the draft guidelines were obtained from other physicians across Canada with HIV expertise. The final guidelines represent the group's consensus agreement. RESULTS AND CONCLUSIONS: The recommendations were developed to guide physicians in optimal practices in patient selection for enfuvirtide treatment and subsequent patient management. The issues considered include positive predictors of response to enfuvirtide, stage of disease, optimization of the background regimen, early indicators of enfuvirtide response, and patient education and support.  相似文献   
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Nephro-ureterectomy is the standard treatment for transitional carcinoma of the renal pelvis and caliceal system. In recent years a modification of the conventional two-incision technique has been described in which the intramural ureter is resected endoscopically and the remaining ureter is removed in continuity with the kidney through a single loin incision. Twenty-one patients had their renal pelvic tumours treated by this modified technique between 1970 and 1983. Of 16 patients available for analysis, 37.5% subsequently developed bladder tumours. It was concluded that this modified technique has no greater incidence of subsequent bladder tumour development than the conventional technique of nephro-ureterectomy, whilst giving considerable benefit to the patient.  相似文献   
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We have investigated the fundamental properties of central auditory glycinergic synapses in early postnatal development in normal and congenitally deaf (dn/dn) mice. Glycinergic miniature inhibitory postsynaptic currents (mIPSCs) were recorded using patch-clamp methods in neurons from a brain slice preparation of the medial nucleus of the trapezoid body (MNTB), at 12-14 days postnatal age. Our results show a number of significant differences between normal and deaf mice. The frequency of mIPSCs is greater (50%) in deaf versus normal mice. Mean mIPSC amplitude is smaller in deaf mice than in normal mice (mean mIPSC amplitude: deaf, 64 pA; normal, 106 pA). Peak-scaled fluctuation analysis of mIPSCs showed that mean single channel conductance is greater in the deaf mice (deaf, 64 pS; normal, 45 pS). The mean decay time course of mIPSCs is slower in MNTB neurons from deaf mice (mean half-width: deaf, 2.9 ms; normal, 2.3 ms). Light- and electron-microscopic immunolabeling results showed that MNTB neurons from deaf mice have more (30%) inhibitory synaptic sites (postsynaptic gephyrin clusters) than MNTB neurons in normal mice. Our results demonstrate substantial differences in glycinergic transmission in normal and congenitally deaf mice, supporting a role for activity during development in regulating both synaptic structure (connectivity) and the fundamental (quantal) properties of mIPSCs at central glycinergic synapses.  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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BACKGROUND: Kaposi's sarcoma (KS) is the most frequent malignancy in patients with HIV. Given the promise that retinoids show in the treatment of various hyperproliferative skin disorders and in vitro evidence of inhibition of proliferation of KS cells, a randomized, controlled clinical trial was conducted. METHODS AND RESULTS: A 12-week, multicenter, randomized, double-blind, vehicle-controlled safety and efficacy evaluation of topical alitretinoin 0.1% gel applied to cutaneous KS lesions was conducted in HIV-infected patients. The primary efficacy endpoint was the patient's response rate, as determined by evaluating six index lesions representative of the patient's overall KS cutaneous disease using AIDS Clinical Trials Group (ACTG) response criteria applied to topical therapy. Of 268 patients entered in the blinded treatment phase of the study (alitretinoin group, n = 134; vehicle group, n = 134), 47 patients (35%) treated with alitretinoin 0.1% gel had a positive response, compared with 24 patients (18%) treated with vehicle gel. Of 184 patients receiving open-label alitretinoin treatment following the blinded phase of the trial, 90 patients (49%) met criteria for a positive response. This superior efficacy of alitretinoin gel over vehicle gel was maintained when the data were adjusted or analyzed for age, race, Kamofsky scores, baseline CD4+ lymphocyte counts, number of raised lesions at baseline, and aggregate area of index lesions. Alitretinoin 0.1% gel was superior to vehicle gel regardless of the number of concurrent antiretroviral therapies. Most adverse events were mild to moderate in severity, limited to the application site, and reversible on reduction in frequency or suspension of application. Relatively few patients (7%) discontinued alitretinoin therapy because of to related adverse events. CONCLUSIONS: The results show that alitretinoin gel application is safe and generally well tolerated, and they indicate the superiority of alitretinoin 0.1% gel over vehicle gel in the treatment of cutaneous AIDS-related KS lesions.  相似文献   
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A method for quantitating the liver, bone, intestinal and placental alkaline phosphatase activity of serum, using an algorithm for converting selective inactivation by guanidine hydrochloride, L-phenylalanine, and heat into equivalent isoenzyme activity is described. The method can individually quantify mixtures of isoenzymes to within a margin of 3%; it has acceptable reproducibility and has been used to develop both age and sex related reference ranges. Analysis time is about 30 minutes. The clinical reliability of this method has been shown in a study of 101 patients, in 79% of whom isoenzyme results were compatible with the final clinical diagnosis; in 10% a clinical diagnosis resulted from isoenzyme analysis, and in a further 11% the source of the increased alkaline phosphatase activity was identified and supported by electrophoresis, with a definite clinical diagnosis yet to be made.  相似文献   
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The torque generated by the shoulder internal and external rotator muscles duringconcentric isokinetic contractions has been investigated. Recordings were made in three positions: neutral, 90 degrees of flexion, and 90 degrees of abduction; and at three speeds of contraction (60, 120, and 180 /sec) in each of these positions. Twelve healthy female university students were randomly selected from a 100 female volunteer population. Testing was accomplished using an isokinetic dynamometer. A two-way analysis of variance for position and speed was conducted. The greatest torque values for the internal rotator muscles were achieved in the neutral position, while maximum values for the external rotators were developed in 90 of shoulder flexion. The test speed of 60 degrees /sec was shown to produce the highest torque values for the external rotator muscles. However, no difference in test speeds of contraction was found when analyzing the torque values generated by the internal rotator muscles. Implications for strength training are discussed.J Orthop Sports Phys Ther 1987;9(6):217-222.  相似文献   
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