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11.
Steffanie Sabbaj Michael F. Para Robert J. Fass Patrick W. Adams Charles G. Orosz Caroline C. Whitacre 《Journal of clinical immunology》1992,12(3):216-224
The lymphocyte proliferative response to recall antigens is lost following HIV infection. We sought to devise a means by which the functional immune status of persons in the early stages of HIV infection could be monitored quantitatively. The response to tetanus toxoid was examined in 45 HIV-infected individuals and 11 controls using conventional lymphocyte proliferative assays concurrently with limiting dilution analysis utilizing the secretion of interleukin-2 as the measure of a response. Our data show that the limiting dilution analysis detects tetanus toxoid-reactive T cells in 80% of those tested, as compared to only 44% by proliferation. However, the frequency of tetanus-reactive T cells in HIV-infected individuals (median frequency = 1/59,156) is decrease five-fold as compared to seronegative controls (median frequency = 1/11,599). Longitudinal studies demonstrated a time-dependent decrease in the frequency of tetanus-specific T cell responses in the HIV-infected individuals. Thus, the limiting dilution analysis is a quantitative approach for detecting antigen-specific T cells in HIV-infected individuals, and may be used to monitor changes in T cell function in HIV infection. 相似文献
12.
Gallyas F Csordás A Schwarcz A Mázló M 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,160(4):473-486
Dark neurons were produced in the cortex of the rat brain by hypoglycemic convulsions. In the somatodendritic domain of each affected neuron, the ultrastructural elements, except for disturbed mitochondria, were remarkably preserved during the acute stage, but the distances between them were reduced dramatically (ultrastructural compaction). Following a 1-min convulsion period, only a few neurons were involved and their environment appeared undamaged. In contrast, 1-h convulsions affected many neurons and caused swelling of astrocytic processes and neuronal dendrites (excitotoxic neuropil). A proportion of dark neurons recovered the normal structure in 2 days. The non-recovering dark neurons were removed from the brain cortex through two entirely different pathways. In the case of 1-h convulsions, their organelles swelled, then disintegrated and finally dispersed into the neuropil through large gaps in the plasma membrane (necrotic-like removal). Following a 1-min convulsion period, the non-recovering dark neurons fell apart into membrane-bound fragments that retained the compacted interior even after being engulfed by astrocytes or microglial cells (apoptotic-like removal). Consequently, in contrast to what is generally accepted, the dark neurons produced by 1-min hypoglycemic convulsions do not die as a consequence of necrosis. As regards the case of 1-h convulsions, it is assumed that a necrotic-like removal process is imposed, by an excitotoxic environment, on dark neurons that previously died through a non-necrotic pathway. Apoptotic neurons were produced in the hippocampal dentate gyrus by intraventricularly administered colchicine. After the biochemical processes had been completed and the chromatin condensation in the nucleus had reached an advanced phase, the ultrastructural elements in the somatodendritic cytoplasm of the affected cells became compacted. If present in an apparently undamaged environment such apoptotic neurons were removed from the dentate gyrus through the apoptotic sequence of morphological changes, whereas those present in an impaired environment were removed through a necrotic-like sequence of morphological changes. This suggests that the removal pathway may depend on the environment and not on the death pathway, as also assumed in the case of the dark neurons produced by hypoglycemic convulsions. 相似文献
13.
Inflammatory pseudotumors have been recognized in many parts of the body. A case of a diffuse variant which involved the testis,
the epididymis and the spermatic cord is described. The patient had enlarged left testis for several months. Clinically, the
lesion mimicred cancer. Histologically, the lesion contained hyalinized fibrous tissue with spindle cells, plasma cells and
lymphocytes. Gradual involvement of vascular channels by the cellular elements of inflammatory pseudotumor was observed. Results
of immunohistochemical studies showed a myofibroblast differentiation in the majority of spindle cells: intense antibody staining
for smooth muscle actin, muscle specific actin, and vimentin. The ultrastructural findings, intracytoplasmic filaments with
dense bodies, were also consistent with the myofibroblastic nature of these cells. The histiocyte differentiation of spindle
cells is questionable in our case, because only scattered histiocyte-like cells showed positivity with the KP-1 (CD-3) antibody. 相似文献
14.
I Orosz 《Orvosi hetilap》1999,140(24):1357-1360
The author discusses the relation of female gender, diabetes mellitus and cardiovascular disease relying upon the "WHO/Europe Health For All" statistical database, data of MEDLINE and the results of Framingham Heart Study. Cardiovascular disease is multifactorial in origin, and it is in connection with increasing prevalence and incidence of diabetes mellitus and hypertension. The mortality caused by ischaemic heart disease is 3-5 times higher if the patients suffer from diabetes mellitus as well. Diabetes mellitus alters the existing difference between males and females in the epidemiological characteristics of ischaemic heart disease. Pathomechanismus (such as metabolic disorders of lipids, hemostasis, endothelial function) are in connection with the changes of estrogen/progesteron balance, have a great role in this change. Diabetes mellitus still has been of significant epidemiological importance from the point of view of cardiovascular's incidence. The prevention of micro-, and macroangiopathy caused by diabetes mellitus beside the genetic factors is one of the most important parts of the epidemiological strategy. 相似文献
15.
Detection of drug-induced apoptosis by flow cytometry after alkaline extraction of ethanol fixed cells 总被引:5,自引:0,他引:5
Mihalik R Uher F Pocsik É Berczi L Benczur M Kopper L 《Pathology oncology research : POR》1996,2(1-2):78-83
A new flow cytometric method was developed to detect apoptotic cells with fragmented DNA and to determine cell cycle distribution
of viable cells, in the same sample, by propidium iodide staining. Apoptosis, in HT58 human B lymphoma cells, was induced
by etoposide and/or by staurosporine. Using appropriate alkaline solutions (between 1-10 mN NaOH in 150 mM saline) followed
by neutralization with buffer solution, the fragmented DNA can be extracted quantitatively from ethanol fixed cells. Further,
good resolution of the cell cycle distribution can be obtained in unimpaired cells without RNase treatment. Furthermore, unlike
the widely used hypotonic-detergent extraction of unfixed cells, the suggested extraction method can prevent drug-induced
disintegration of dead cells when karyorrhexis occurs.
This work was supported by Hungarian National Research Foundation (OTKA I/352 and OTKA II/2622). 相似文献
16.
The number of lethal cases in hospitals keeps decreasing from year to year, whereas the rate of omitted post-mortem examinations increases. The "control" role of autopsy decreases consequently. Autopsy is omitted even in cases that have been considered as possibly "extraordinary" at the beginning of the procedure and this may mean danger also from the viewpoint of criminology. According to the observations of the authors there are still uncertainties (irregularities?) concerning the tasks connected with the autopsy of those who died in hospitals, as legal injunctions are lacking. On the basis of their experiences the authors interpret the related legal measures and describe the essentials of the procedural practice considered by them correct. 相似文献
17.
Ferenc Bánhidy Erzsébet Puhó Nándor Acs Andrew E Czeizel 《The journal of maternal-fetal & neonatal medicine》2006,19(9):537-542
OBJECTIVE: To study the possible association between orofacial herpes during pregnancy and pregnancy complications including preterm birth and low birth weight, since the results of previous studies are inconsistent. METHOD: The population-based large data set of the Hungarian Case-Control Surveillance System of Congenital Abnormalities was used; pregnancies in mothers with and without recurrent orofacial herpes were compared. RESULTS. Of 38,151 newborn infants, 572 (1.5%) had mothers with recurrent orofacial herpes during pregnancy, while 37 577 had mothers with no orofacial herpes. Pregnant women with recurrent orofacial herpes had a higher prevalence of severe nausea and vomiting, threatened preterm delivery, and placental disorders but a lower prevalence of preeclampsia. Mothers with recurrent orofacial herpes during pregnancy also had a somewhat longer (0.4 weeks) gestation (adjusted t = 2.7; p = 0.006) and an obviously lower proportion of preterm births (3.5% vs. 9.3%; adjusted POR with 95% CI = 0.42, 0.27-0.65). However, there was no significant difference in the mean birth weight and rate of low birth weight infants between the two study groups. CONCLUSION: Recurrent orofacial herpes during pregnancy is associated with a smaller proportion of preterm births. 相似文献
18.
19.
Rita Nagy Klementina Ocskay Alex Vradi Mria Papp Zsuzsanna Vitlis Ferenc Izbki Eszter Boros Lszl Gajdn Andrea Szentesi Blint Erss Pter Jen Hegyi ron Vincze Judit Bajor Patricia Sarlos Alexandra Mik Katalin Mrta Dniel Pcsi Andrea Prniczky Pter Hegyi 《Nutrients》2022,14(10)
Although excessive alcohol consumption is by far the most frequent cause of recurrent acute pancreatitis (AP) cases, specific therapy is still not well established to prevent recurrence. Generally, psychological therapy (e.g., brief intervention (BI)) is the cornerstone of cessation programs; however, it is not yet widely used in everyday practice. We conducted a post-hoc analysis of a prospectively collected database. Patients suffering from alcohol-induced AP between 2016 and 2021 received 30 min BI by a physician. Patient-reported alcohol consumption, serum gamma-glutamyl-transferase (GGT) level, and mean corpuscular volume (MCV) of red blood cells were collected on admission and at the 1-month follow-up visit to monitor patients’ drinking habits. Ninety-nine patients with alcohol-induced AP were enrolled in the study (mean age: 50 ± 11, 89% male). A significant decrease was detected both in mean GGT value (294 ± 251 U/L vs. 103 ± 113 U/L, p < 0.001) and in MCV level (93.7 ± 5.3 U/L vs. 92.1 ± 5.1 U/L, p < 0.001) in patients with elevated on-admission GGT levels. Notably, 79% of the patients (78/99) reported alcohol abstinence at the 1-month control visit. Brief intervention is an effective tool to reduce alcohol consumption and to prevent recurrent AP. Longitudinal randomized clinical studies are needed to identify the adequate structure and frequency of BIs in alcohol-induced AP. 相似文献
20.
Recently, it has been suggested, that differentiated cells are more resistant to the apoptotic effect of DNA damaging agents
possibly due to the decreased activity of “damage detecting/apoptosis triggering” mechanism. Previously, we have shown, that
PMA pretreatment reduced etoposide-(ETO) but enhanced staurosporine- (STA) -induced apoptosis in HT58 cells. Data presented
here show that the HT58 human, “mature” B-lymphoma cells exposed to PMA secrete more IgM into the supernatant indicating commitment
of cells to perform differentiated function. The sensitivity of HT58 cells to ETO- or STA-induced apoptosis is influenced
diversely with PMA pre- or posttreatment. Interestingly, the DNA damage (gamma radiation, bleomycin, ETO) or okadaic acic
(30 nM) reduced the [PMA+STA] - induced apoptosis. 相似文献