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31.
Parapharyngeal cystic hygroma is a rare tumor of the neck. This report describes two cases in which surgical resection was necessary to overcome sudden airway obstruction and details the surgical technique. These cases were considered "near misses" for sudden infant death syndrome (SIDS) and were revealed by computed tomography (CT) and echography to be parapharyngeal cystic hygroma. The location of this malformation could have produced sudden airway collapse and be erroneously diagnosed as SIDS. The postoperative follow-up was satisfactory and no recurrence was detected. We believe CT and echography should be included in the evaluation of such cases.  相似文献   
32.
Analysis of the local cell-mediated immunity within the central nervous system is limited by the small amount of material available. In the present report we describe that T lymphocyte clones can be expanded directly from the cerebrospinal fluid (CSF) using T cell growth factor and irradiated feeder cells. Without in vitro restimulation such clones can reproducibly be generated from fresh or cryopreserved CSF lymphocytes. From a patient with tuberculous meningitis, T lymphocyte clones were obtained that showed tuberculin (PPD) specific proliferative responses restricted by a single HLA-DR antigen. One of these clones was restricted by an antigen different from the serologically defined HLA-DR since this clone recognized PPD only on autologous but not on HLA-DR matched monocytes. These experiments show that T lymphocytes involved in the in situ immune response can be cloned directly from the site of inflammation.  相似文献   
33.
Total serum IgE levels were determined in 136 newborns and their mothers and in 54 of their fathers, using the paper radioimmunosorbent test (PRIST) technique. IgE specific antibodies for house dust (Dermatophagoides pteronyssinus), orchard grass, timothy grass, and cow's milk were measured with the radioallergosorbent test (RAST). One hundred thirty-three RAST assays were negative in newborns, and in three cases RAST for cow's milk was positive. Cord blood IgE ranged from 0 to 5.5 IU/ml (mean 0.32 ± 0.54 IU/ml); levels were significantly (p < 0.05) higher when maternal IgE was over 100 IU/ml and when mothers had received progesterone therapy during the pregnancy. Salbutamol administration or tobacco smoking during pregnancy did not influence newborn IgE. A clinical follow-up study was conducted in 83 infants for 9 mo. Nine infants developed definite atopic disease, and possible allergic diseases were noted in eight other infants. The IgE level at birth appeared to be more predictive for the development of allergy in infancy than the family history.  相似文献   
34.
Twenty-five rabbits were used to study the effect of glossopharyngeal nerve transection upon the number, size and cellular constitution of the taste buds. The glossopharyngeal nerve was cut on one side, the other being left undisturbed as a control. The animals were sacrificed in groups of three after 7, 10, 14, 21, and 30 days, and 2 and 4 months after the operation. Seven days after the operation the size and number of intragemmal cells were decreased in the taste buds. The taste pores with hairlets passing through them disappeared. The number of taste buds on circumvallate papillae decreased. After ten days taste buds in both types of papillae showed signs of degeneration. Fourteen days after the operation there was a marked decrease in size and number of taste buds. The circumvallate papillae now possessed no taste buds. After 21 days few taste buds were present in foliate gutters. These consisted of one or two sustentacular cells each. After 30 days there were no taste buds on foliate papillae, and thickness of the epithelium lining the gutters was decreased. Two or four months after denervation, the foliate gutters were shallow and some had become flattened. The importance of the gustatory nerve for development and maintenance of the normal status of the taste buds is discussed.  相似文献   
35.
Patients with agammaglobulinemia may excrete enteroviruses, including vaccine-derived poliovirus, for prolonged periods of time. This poses a risk to the patients but it also may pose a risk to the population after eradication of poliovirus and the cessation of routine vaccination. To assess this risk, a pilot study was performed to identify potential poliovirus long-term excretors in a cohort of 38 patients with a definite/presumptive diagnosis of X-linked agammaglobulinemia (XLA). Stool samples were analyzed to detect any polio or other enteroviruses replicating in the gut and neutralizing antibodies against polioviruses were measured in the sera. No viruses were isolated from the stool samples and most sera had neutralizing antibody levels against all three poliovirus serotypes considered by the WHO to be protective in immunocompetent individuals. This suggests that long-term excretion of enteroviruses in patients with agammaglobulinemia is relatively uncommon.  相似文献   
36.
Distinction of high-grade esthesioneuroblastomas from other poorly differentiated tumors arising in the nasal cavity is an important diagnostic challenge because it determines patient management and prognosis. The human achaete-scute homologue (hASH1) gene is critical in olfactory neuronal differentiation and is expressed in immature olfactory cells; therefore, it could have potential use as a diagnostic marker The aim of the present study was to determine the value of hASH1 messenger RNA (mRNA) levels in differentiating esthesioneuroblastoma from other poorly differentiated tumors. A real-time polymerase chain reaction assay was developed, permitting the comparative determination of hASH1 mRNA levels in triplicate in a double-blind pilot study including 24 frozen cases of esthesioneuroblastoma and poorly differentiated tumors. All 4 positive cases were esthesioneuroblastomas, and all 19 poorly differentiated tumors were negative. In addition, there was an inverse association between the grade of esthesioneuroblastomas and hASH1 mRNA levels. The hASH1 mRNA level might represent a useful tool for distinguishing esthesioneuroblastoma from poorly differentiated tumors of the sinonasal region.  相似文献   
37.
Rats with thalamic taste nuclei lesions were adapted to a 23 hr 50 min deprivation schedule and then presented with 0.125 percent saccharin followed by an injection of LiCl or saline. When retested with saccharin, animals with lesions showed a marked attenuation in taste aversion as compared to controls.  相似文献   
38.
Thirty patients with dyspepsia, with histological diagnosis of gastritis, and with endoscopic diagnosis of peptic ulcer disease (PUD) (n = 13) or nonulcer dyspepsia (NUD) (n = 17) were admitted to the study. Helicobacter pylori vacuolating cytotoxin-producing strains (Tox+) were isolated from 14 (46.7%) patients, whereas non-cytotoxin-producing (Tox-) H. pylori strains were isolated from the remaining patients. Of 30 patients studied, 20 (66.7%) had serum cytotoxin neutralizing activity in vitro. Fourteen patients with Tox+ H. pylori strains showed serum cytotoxin neutralizing activity and serum immunoglobulin G (IgG) and IgA antibodies reactive with both 87-kDa H. pylori vacuolating cytotoxin (VacA) and 128-kDa cytotoxin-associated gene product (CagA) by immunoblotting using native enriched preparations of VacA and CagA proteins from H. pylori culture supernatants as the antigens. A 94-kDa antigen cross-reacting with the 87-kDa VacA protein could be demonstrated in culture supernatant with immune sera from humans and animals. All patients (n = 10) lacking serum neutralizing activity were also negative for IgG or IgA against VacA antigen, whereas 6 of the 10 patients showed IgG serum antibody responses against CagA antigen. The prevalence of antibodies to VacA and CagA antigens was significantly (P < 0.001) higher in patients with gastritis (20 and 26 patients for VacA and CagA, respectively, of 30 patients) than in H. pylori culture-negative controls (0 of 27 for both VacA and CagA) and in randomly selected blood donors (17 and 21 for VacA and CagA, respectively, of 120 subjects). All patients with PUD had antibodies to CagA, whereas 13 of 17 (76.5%) patients with NUD had anti-CagA antibodies. Serum IgG antibodies to VacA were present in 9 (69.2%) patients with PUD of 13 patients and in 11 (64.7%) patients with NUD of 17 patients. Anti-CagA antibodies seemed to correlate better with PUD than anti-VacA antibodies.  相似文献   
39.
In women undergoing in-vitro fertilization and embryo transfer(TVF-ET), a total of 408IVF cycles were stimulated using humanmenopausal gonadotrophin (HMG) or pure follicle stimulatinghormone (FSH) plus HMG in combination with a single injectionof D-Trp6-LHRH microcapsules in order to enhance the ovarianresponse to gonadotrophins and to avoid spontaneous LH surges.Sixty-seven pregnancies were achieved. Two protocols were employed.In protocol 1 (‘blocking protocol’, n = 268), thepituitary was first inhibited with a full dose (3.75 mg) ofD-Trp6-LHRH in microcapsules and ovarian stimulation was startedafter the hypogonadotrophic hypogonadal state was ascertained(Ej >50 pg/ml). In protocol 2 (‘flareup protocol’,n = 140), the treatment with D–Trp6LHRH microcapsules(half-dose = 1.80 mg) and the ovarian stimulation with gonadotrophinswere started at the same time. Higher doses of gonadotrophinswere needed (39.5 11.2 ampoules FSH and/or HMG) in protocol1, in which the pituitary was blocked prior to and during thestimulation, than in protocol 2 (209 ampoules) where the exogenousgonadotrophin stimulation appeared to be augmented by the initialagonistic effect of the injection of D-Trp6LHRH microcapsules.In patients with purely tubal infertility, under 38 years oldand no male factor, the results obtained with protocols 1 and2 were similar in terms of pregnancy rate per cycle or per embryotransfer: 22.6 versus 20.5% and 28.3 versus 27.4%, respectively.However, considering the cost benefit, ‘flare-up’protocols appeared to be a better choice and could be recommended.  相似文献   
40.
The anionic polymerization of styrene in tetrahydrofuran initiated by a bifunctional organo-barium derivative shows a remarkable property: for a given temperature the propagation rate does not depend on carbanion concentration in the range from 3.10?5 to 5.10?3 mol/l. This corresponds to a linear relationship between the rate constant of propagation kp and the reciprocal of active sites concentration. The activation energy of propagation is equal to 4,1 kcal/mol (17,1±1,3 kJ/mol). Our experimental results were interpreted assuming that “living” polymer molecules form rings, their two anionic ends being associated through a divalent cation, and that they constitute aggregates with a “rosace” type structure. The validity of this assumption is supported by spectral and viscosimetric studies of living polymer solutions.  相似文献   
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