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121.
An improved and simpler plaque assay method for antibody-dependent cell-mediated cytotoxicity using Cunningham's chamber has been developed. Effector lymphocytes, target sheep red blood cells (SRBC) and anti-SRBC serum were incorporated together into a Cunningham's chamber and, immediately after making monolayers, incubated at 37°C for 20 h. A hemolytic plaque of SRBC was formed around a lymphocyte in the presence of anti-SRBC serum, which was inhibited specifically by addition of aggregated IgG or Fc-fragment of human IgG in the culture. A hemolytic plaque formed around a monocyte-like cell was clearly differentiated from those around a lymphocyte (K-cell). The percentage of plaques in the purified lymphocytes from healthy individuals correlated significantly with ADCC activity measured by 51Cr-release. The method is a significant improvement on the earlier plaque assay methods with regard to: (1) making the monolayer, (2) observation and counting of plaques, and (3) shortening the time required for assay. Thus, the method should be valuable for clinical studies of cytotoxic activity in ADCC systems in healthy and diseased persons.  相似文献   
122.
Estradiol benzoate administered to ovariectomized female rats significantly elevated the mean spontaneous firing rate and frequency of successful antidromic propagation into the somatodendritic spike and significantly reduced the strength of post-stimulus inhibition in presumed A1 noradrenergic neurons projecting directly to the preoptic and anterior hypothalamic area. The occurrence of both antidromic spikes and post-stimulus inhibition of the majority of these neurons was completely abolished by the injection of 6-hydroxydopamine but not by 5, 7-dihydroxytryptamine directly into the medial forebrain bundle.  相似文献   
123.
Seventeen neurons in the subfornical organ (SFO) were antidromically activated by electrical stimulation of the paraventricular nucleus (PVN) in the rat. The activity of all identified SFO neurons was excited by microiontophoretically (MIPh) applied angiotensin II (AII) and the effect of AII was blocked by MIPh-applied saralasin (Sar), an AII antagonist, but not by atropine (Atr), a muscarinic antagonist. In these identified SFO neurons, 9 were also excited and 8 were not affected by MIPh-applied acetylcholine (ACh) and the effect of ACh was attenuated by not only MIPh-applied Atr but also by Sar. These results suggest that there are specific AII- and both AII- and ACh-sensitive types of SFO neurons with efferent projections to the PVN.  相似文献   
124.
Electrical stimulation of the rat A1 noradrenergic region produced excitation (77%) of the activity of putative vasopressin (VP)-secreting neurons in the paraventricular nucleus (PVN) and produced excitation (4%), inhibition (26%) and excitation-inhibition (11%) of the activity of PVN neurons that were not antidromically identified by neurohypophysial stimulation. The excitatory response of putative VP-secreting neurons was blocked by microiontophoretically applied phentolamine, an α-adrenoceptor antagonist, but not by timolol, a β-adrenoceptor antagonist. The inhibitory response of unidentified PVN neurons, on the other hand, was blocked by timolol, but not by phentolamine.  相似文献   
125.
Xanthogranulomatous Cholecystitis Masquerading as Gallbladder Carcinoma   总被引:4,自引:0,他引:4  
We herein present a case of xanthogranulomatous cholecystitis which involved hoth the liver and transverse colon, clinically mimicking gallbladder carcinoma. Such cases may sometimes he judged inoperable due to extensive extra-gallbladder invasion, and thus it is necessary for physicians to take this lesion into consideration when making a diagnosis. An intraoperative biopsy is necessary, therefore, even when the feaures seem to clearly indicate inoperable carcinoma.  相似文献   
126.
The response of a highly metastatic cell line of methylcholanthrene induced A fibrosarcoma (Meth A) to growth factors from platelets was examined. The highly metastatic cell subline (MH) proliferated more rapidly than its parental counterpart cell subline (ML) in a medium containing platelet lysate. However, when the three major growth factors from platelets, ie, platelet-derived growth factor, epidermal growth factor, and transforming growth factor-β(PDGF, EGF, TGF-β), were independently examined for their growth promoting activity, the former 2 growth factors preferentially stimulated the proliferation of ML and the latter growth factor rather suppressed the growth of both cells.

On the other hand, the combined effects of these factors were more marked on MH. This combination effect was supported by the evidence that the number of receptors for EGF (which is probably an essential growth factor for the Meth A cell) was increased by pretreatmenl with PDGF or TGF-β. Thus, the highly metastatic cells of MH were considered to be the most susceptible to growth factors released from platelets. This conclusion is consistent with the concept that platelets may play an important role in the formation of blood-borne metastasis by releasing growth factors to promote the proliferation of tumor cells, following aggregation with tumor cells.  相似文献   
127.
简述从四氢吡喃丙炔醇(3)和1-溴-4-氯丁烷(4)开始经6步反应制备7-氰基-1-二甲步丁硅氧基-2-,3-反-环氢庚烷(5),此化合物是合成(+)-布雷菲德菌素A中间体的原料。  相似文献   
128.
Twice daily injections of 1.0 or 5.0 mg/kg D-amphetamine for 6 consecutive days differentially affected the response of dopaminergic neurons in the substantia nigra pars compacta to challenge injections of apomorphine on the following day. Thus, whereas treatment with the high amphetamine dose produced a dramatic shift to the right of the apomorphine dose-response curve, rats treated with 1.0 mg/kg D-amphetamine responded to apomorphine in the same way as saline-treated controls. These results support the view that long-term treatment with relatively high amphetamine doses is required to produce autoreceptor subsensitivity in the substantia nigra.  相似文献   
129.
Peripheral blood lymphocytes of 16 patients with secretory type of multiple myeloma and 5 with nonmyelomatous monoclonal gammopathy were investigated for the surface immunoglobulins on the cell by immunofluorescence. A low pH shock of cells before staining was applied to dissociate the passively adsorbed immunoglobulins present on the cell surface. Increases of B lymphocytes bearing surface immunoglobulins which have the same light chains as those of monoclonal immunoglobulins produced by the plasma cells were found in 5 of 11 common secretory myeloma patients and in all of 6 Bence-Jones myeloma patients. Ratios of cells bearing light chains of k- and λ-types (k/λ) appeared abnormal in almost all with an exception of only 3 cases of myeloma patients, even in the cases where the number of Ig-bearing cells did not increase. Increases of possible monoclonal B cells bearing IgG, in addition to IgA cells, were observed in some patients with IgA myeloma. Increases of B cells bearing certain heavy chains were also observed in all 5 patients with Bence-Jones myeloma during the course of disease. No abnormalities of B cells bearing surface immunoglobulin were found in nonmyelomatous monoclonal gammopathy. These results suggest that proliferation of monoclonal B lymphocytes, which may be progenitors to the malignant plasma cells, occurs in a majority of myeloma patients, but not in nonmyelomatous monoclonal gammopathy.  相似文献   
130.
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