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991.
John F. Teare Roger W. Peterson Karen Authier Linda Schroeder Daniel L. Daly 《Child & youth care forum》1998,27(2):125-138
The purpose of this study was to examine the correlates of post-shelter maternal family satisfaction in a group of youth who
were reunified with their families following a shelter stay. Findings indicated that higher ratings of family satisfaction
were related to greater maternal problem solving skill and less family conflict. 相似文献
992.
Azra Raza Harvey D. Preisler Ya Qin Li Richard A. Larson Jack Goldberg George Browman John Bennett Hans Grunwald Ralph Vogler Cathi Kukla 《American journal of hematology》1993,42(4):359-366
A pilot study was conducted of the biological characteristics of the leukemia cells of newly diagnosed patients with poor prognosis acute myelogenous leukemia (AML). This study included measurements of the pretherapy proliferative rate of the leukemia cells in vivo, assessment of differentiation in vivo during remission induction therapy, and the level of expression of the fms, myc, and IL1β genes in pretherapy leukemia cells. Short cell cycle times were characteristic of the best prognostic category and were associated with a rapid reduction in marrow leukemia cells in cytosine arabinoside (araC)-sensitive patients. Expression of c-fms was associated with rapid reduction in marrow leukemia cells during araC therapy and with a successful treatment outcome. Expression of the IL1β gene was associated with short remissions. These studies suggest that when compared to newly diagnosed standard prognosis AML, the leukemia of poor prognosis patients is more likely to exhibit long cell cycle times, low levels of fms expression, and is less likely to be associated with myeloid differentiation during remission induction therapy. © 1993 Wiley-Liss, Inc. 相似文献
993.
Rajiv Tandon Robert Goldman John R. DeQuardo Mona Goldman Melinda Perez Michael Jibson 《Journal of psychiatric research》1993,27(4):341-347
Although negative symptoms were traditionally considered to be unresponsive to neuroleptic medication, recent studies have demonstrated that negative symptoms do improve during neuroleptic treatment and that such improvement tends to occur concurrently with improvement in positive symptoms. Clozapine is an atypical neuroleptic that is effective in a significant proportion of otherwise neuroleptic-nonresponsive schizophrenic patients; in contrast to conventional neuroleptics, clozapine is also purported to possess unique efficacy in the amelioration of negative symptoms. How clozapine-associated reduction in negative symptoms relates to change in positive symptoms is not clear. To study the relationship between change in positive and negative symptoms during clozapine treatment, we monitored symptomatology in 40 DSM-III-R schizophrenic patients before and about 8 weeks after a trial of clozapine. Both positive and negative symptoms improved significantly. There was a significant correlation (r = .63,p <.01) between change in positive symptoms and change in negative symptoms; as with conventional neuroleptics, negative symptoms improved concomitantly with positive symptoms during clozapine treatment. Clozapine's apparent greater efficacy on negative symptoms may be related to its greater efficacy on positive symptoms in otherwise neuroleptic-refractory patients and its lesser propensity to cause extrapyramidal side-effects. 相似文献
994.
995.
996.
We hypothesized that sensory input from the moving leg induces presynaptic inhibition of the soleus H reflex pathway in the contralateral stationary leg. The results showed a crossed inhibition during passive pedalling movement of the leg, which was not removed by low levels of tonic contraction of soleus in the stationary leg. The inhibition was correlated exponentially to the rate of the movement (R2=0.934, P<0.05) and was not dependent on the quadrants through which the moving leg was passing. Static flexion of the stationary leg caused ipsilateral inhibition of the reflexes (t=5.590, P<0.05), independent of the orientations of the other leg. We concluded that sensory inflow from the moving leg induces presynaptic inhibition in the stationary leg, that a complex transformation of the sensory input in the spinal cord or brain underlies the tonic crossed inhibition and phasic ipsilateral inhibition, and that descending motor commands exert a powerful control over these sensorimotor modulatory mechanisms. 相似文献
997.
Recent studies have shown that tetrafluoroethylene is a renal and hepatic carcinogen in the rat. In this study, we have examined
the ability of a single i.p. dose of 1,1,2,2-tetrafluoroethyl-l-cysteine (TFEC), a major metabolite of tetrafluoroethylene, to produce hepatic and renal injury in male and female rats.
We have also examined the effect of blocking the renal organic anion transport system with probenecid and of inhibiting the
activity of cysteine conjugate β-lyase with aminooxyacetic acid on the extent of renal injury produced by TFEC. Doses of ≥12.5 mg/kg
TFEC produced renal tubular necrosis to the pars recta of the proximal tubules within 24 h in both male and female rats. This
was associated with an increased kidney to body weight ratio and plasma urea at doses of ≥25 mg/kg. No consistent evidence
of liver injury was seen at doses up to 50 mg/kg TFEC in rats of either sex, although occasional vacuolation of hepatocytes
and a small dose-related increase in liver to body weight ratio was observed. Prior treatment of female rats with probenecid
completely prevented the renal injury produced by either 25 or 50 mg/kg TFEC as judged by plasma urea and histopathology.
However, prior treatment of female rats with aminooxyacetic acid afforded no protection against the nephrotoxicity produced
by either TFEC or the cysteine conjugate of hexachloro-1,3-butadiene. Thus no major sex difference in nephrotoxicity in the
rat was seen with TFEC, while accumulation of TFEC, or its N-acetyl derived metabolite, into renal proximal tubular cells
via a probenecid sensitive transport system appears to be a key event in the mechanism of nephrotoxicity. The lack of protection
observed with the cysteine conjugate β-lyase inhibitor, aminooxyacetic acid, may reflect the inability to completely inhibit
the mitochondrial form of this enzyme and thereby prevent the formation of the reactive metabolite. Our acute studies provide
no insight concerning the liver carcinogenicity of tetrafluoroethylene.
Received: 8 December 1997 / Accepted: 3 February 1998 相似文献
998.
999.
Post-infectious bronchiolitis obliterans: clinical, radiological and pulmonary function sequelae 总被引:6,自引:0,他引:6
Background. There are few data on clinical, chest radiograph (CXR) or pulmonary function sequelae in children with post-infectious bronchiolitis
obliterans (BO) (pulmonary crepitations, abnormalities on CXR, CT, nuclear medicine scans, or bronchography, with a history
of past pulmonary infection and in the absence of other underlying pathology). Objective. To analyse the methodology of diagnosis, long-term clinical imaging and pulmonary function sequelae of post-infectious BO
in children. Materials and methods. Imaging (CXRs, CT and nuclear lung scans) and clinical histories of 19 children were analysed. Results. Clinical follow-up (mean 6.8 years), revealed a high incidence of continuing problems (asthma and bronchiectasis). Fixed
airway obstruction was the most common pulmonary function sequela. The sequelae on follow-up (mean 5.8 years) CXR were classified
into five patterns which are illustrated: unilateral hyperlucency of an enlarged lung/part of lung; complete collapse of the
affected lobe; unilateral hyperlucency of a small or normal-sized lung; bilateral hyperlucent lungs and a mixed pattern of
persistent collapse, hyperlucency and peribronchial thickening. Conclusion. Long-term observations in children with post-infectious BO should be undertaken to detect bronchiectasis and obstructive
airway disease. Sequelae evident on CXR, other than those previously described, can be found. Bronchography and/or lung biopsy
are not usually required for the diagnosis of post-infectious BO.
Received: 15 January 1997 Accepted: 23 June 1997 相似文献
1000.