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91.
Because attitudes concerning a topic can diminish the effectiveness of educational materials, previously identified attitudes concerning calcium intake were explored through focus group interviews during the developmental stages of calcium education materials. Although four focus groups of six to seven participants were planned, each of the four groups consisted of two to six women. All focus groups followed the same format, lasting for 60–90 min; questions progressed from the general to more specific. The focus groups revealed several attitudinal barriers toward dietary behavioural change, including lack of prior interest in the topic and lack of time. Attitudes about dairy calcium included the belief that dairy foods were high in fat and should be avoided, and the belief that dairy foods would cause stomach upsets. Also, neither younger nor older women felt that osteoporosis was a problem their age group needed to address. Readability scales were not necessarily predictive of preference. This study shows that focus group interviews make a valuable contribution to planning and evaluating nutrition education materials.  相似文献   
92.
Short-term and long-term carcinogenicity of methyl carbamate (MCB) was evaluated in F344 rats and B6C3F1 mice. In experiments lasting 6, 12, and 18 months, MCB was given in water by gavage to groups of 10 male and 10 female rats at 0 or 400 mg/kg body weight, 5 days per week, and to similar groups of mice at 0 or 1,000 mg/kg. At 6 months, MCB induced atypical mitoses, cytologic alterations, cytomegaly, pigmentation, necrosis, and neoplastic nodules of the liver in rats. At 12 and 18 months, carcinomas of the liver were induced by MCB in 80-90% of male rats and in 60-80% of female rats. None was observed in control rats or in mice. In the 2-year studies, MCB was given to groups of 50 male and 50 female rats at 0, 100, or 200 mg/kg and to similar groups of mice at 0, 500, or 1,000 mg/kg, 5 days/week. Chronic focal inflammation, cytologic alteration, hyperplasia, and neoplastic nodules and carcinomas (200 mg/kg groups only) of the liver were induced by MCB in rats. Liver tumor incidence data for combined experiments in rats were: males--5% in controls, 0% in 100 mg/kg group, 14% in 200 mg/kg group, and 77% in 400 mg/kg group; females--5% in controls, 0% in controls, 0% in 100 mg/kg group, 12% in 200 mg/kg group, and 63% in 400 mg/kg group. MCB was not shown to be carcinogenic in mice.  相似文献   
93.
We present improvements of a previously reported method of tracheoesophageal puncture for voice restoration in postlaryngectomy patients. Our method utilizes a flexible endoscope to enable the tracheoesophageal puncture to be made under direct visualization using only local anesthesia and intravenous sedation. After 3 days, the created tracheoesophageal fistula tract is mature enough to allow placement of a voice prosthesis in the office. This allows the entire procedure to be performed in an outpatient setting with minimal risk. Received: 24 October 1996/Accepted: 24 January 1997  相似文献   
94.
Background: Investigators in the authors' laboratory previously established the critical participation of the cerulospinal noradrenergic pathway in muscular rigidity elicited by fentanyl. The identification of colocalization of glutamate with tyrosine hydroxylase in most locus ceruleus neurons suggests a role for cerulospinal glutamatergic neurotransmission in fentanyl-induced muscular rigidity. This suggestion and the subtype(s) of glutamate receptors involved were investigated here.

Methods: Electromyographic signals activated by bilateral microinjection of 2.5 micro gram fentanyl into the locus ceruleus were recorded differentially from the left sacrococcygeus dorsi lateralis muscle of adult male Sprague-Dawley rats. The effect of intrathecal administration at the lower lumbar spinal cord of various N-methyl-D-aspartate (NMDA) and non-NMDA receptor antagonists or agonists on this index of muscular rigidity was studied. Rats were under mechanical ventilation, and intravenous infusion of ketamine (30 mg [center dot] kg sup -1 [center dot] h sup -1) was maintained until 10 min before fentanyl was administered.

Results: Microinjection of fentanyl bilaterally into the locus ceruleus increased the root mean square and decreased the mean power frequency values of electromyographic signals. The efficacy of fentanyl to elicit muscular rigidity in this manner was significantly reduced by previous intrathecal administration of either 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate (MK-801), D-(-)-2-amino-5-phosphonovaleric acid (AP5), or (+/- (CPP). Intrathecal administration of kainic acid or NMDA also resulted in significant electromyographic activation.  相似文献   

95.
Growth retardation is a major complication in children with uremia. Protein restriction, calorie deficit, metabolic acidosis, renal osteodystrophy, and endocrinologic disturbances contribute to the growth failure. The effect of these factors on growth retardation can be attenuated in part by therapy with vitamin D metabolites, adequate nutrition, alkalization, and dialysis. Linear growth in children with uremia is markedly retarded despite normal or increased levels of circulating serum growth hormone. An increased growth hormone level in children with uremia is due to normal growth hormone secretion from the pituitary gland and impaired growth hormone clearance in the kidney. However, the elevated growth hormone level does not lead to a commensurate rise in serum insulin-like growth factor I (IGF-I); the serum IGF-I level is decreased or normal in relation to the degree of renal failure. This discrepancy suggests growth hormone resistance in the liver in uremia. Recent molecular techniques open a new era in studying the gene expression for growth hormone or IGF-I. There is no doubt today that growth hormone treatment has the beneficial effect of growth promotion in children with uremia, which also suggests endogenous growth hormone resistance in target organs or target cells in uremia.  相似文献   
96.
The hepatitis B immunization programme in Singapore   总被引:2,自引:0,他引:2  
A voluntary immunization programme to prevent perinatal transmission of hepatitis B virus (HBV) infection in Singapore was implemented on 1 October 1985 as an integral component of the national childhood immunization programme. Up to April 1988, a total of 68,845 mothers who attended government maternal and child health clinics were screened for the disease. Of these, 2432 (3.5%) were positive for hepatitis B surface antigen (HBsAg) and 904 (1.3%) for hepatitis B e antigen (HBeAg). Virtually all the babies born to carrier mothers completed the full immunization schedule; and in addition, those of HBeAg-positive mothers were given a dose of hepatitis B immunoglobulin at birth. The hepatitis B immunization programme was extended on 1 September 1987 to cover all newborns. About 90% of the 15,943 babies delivered in government institutions from September 1987 to April 1988 were immunized at birth, with the subsequent doses being administered at maternal and child health clinics at 4-6 weeks and 5 months later. More than 85% of the children given the full course of plasma-derived and yeast-derived hepatitis B vaccine from birth continued to have protective antibody to HBV two years after immunization. The programme is being closely monitored to assess the duration of immunity and the need for booster doses, while seronegative adults are also being encouraged to be vaccinated.  相似文献   
97.
An algorithm is presented that has been developed over the past three years to provide pain relief in advanced cancer. The hospital records of 92 patients were reviewed to evaluate the validity of the algorithm. The algorithm is as follows: the 24 hour oral consumption of opioids was converted to sustained release morphine. If ineffective usually over 360 mg daily the total 24 hour oral dose was divided by 6 to convert to I.V. If this was ineffective, usually over 10 mg/hr of morphine, the intravenous dose was divided by 10 and infused epidurally. Local anesthetic was added for plexus involvement. After four days, the patient was weaned from local anesthetic solution. If sharp pain or pain to movement persisted, 6% phenol in 1 to 2 ml aliquots was injected every 8-12 hours to a total of 5-8 ml. While the conversion from intravenous to epidural morphine was 10:1 that from epidural to intravenous was only 1:3. Intravenous dose converts directly to the subcutaneous. The conversion from intravenous to oral is 1:3. There view showed that the dosages at which the conversions were made varied considerably. The reasons for the wide variation are presented. In summary the algorithm is a good practical guide for treatment of cancer pain.  相似文献   
98.
During the development of a homogeneous immunoassay for the antibiotic vancomycin, we observed in certain patient samples a quantitation difference between the enzyme multiplied immunoassay technique (EMIT) method and the comparison method, fluorescence polarization immunoassay (FPIA). This prompted us to evaluate the integrity of vancomycin in samples from renally impaired patients. Since it has been reported in the scientific literature that vancomycin degrades into an antibiotically inactive crystalline degradation product (CDP-1) in vitro, we developed high-performance liquid chromatography (HPLC) and liquid chromatography/mass spectrometry (LC/MS) methods to determine whether CDP-1 is present in patient sera. HPLC and LC/MS analysis on samples from renally impaired patients positively identified CDP-1 in fresh samples. Next, we tested the cross-reactivity of three currently available vancomycin immunoassays, radioimmunoassay (RIA) FPIA, and EMIT, to CDP-1 prepared in our laboratory. Our data suggest that CDP-1 is recognized by FPIA and RIA, both polyclonal antibody-based methods, but not by EMIT, which uses a monoclonal antibody.  相似文献   
99.
OBJECTIVE: This study was undertaken in order to determine the risk factors for pregnancies complicated by placental abruption in a socio-economically disadvantaged region in metropolitan Adelaide. METHODS: This was a retrospective case-control study including all singleton pregnancies resulting in placental abruption between 2001 and 2005. RESULTS: The overall incidence of placental abruption was 1.0%; the overall perinatal mortality among the births with abruption was 13%. Univariate analyses showed the following significant risk factors for placental abruption: preterm pre-labor rupture of the membranes (PRE-PROM; odds ratio (OR) 4.79, 95% confidence interval (CI) 1.52-15.08), non-compliance with antenatal care (OR 2.93, 95% CI 1.06-8.90), severe intrauterine growth restriction (IUGR), and elevated homocysteine levels (OR 45.55, 95% CI 7.05-458.93). Severe IUGR was significantly more common in the abruption group compared with the control group (p = 0.032). In the multivariate analysis, PRE-PROM remained a significant independent risk factor for placental abruption. Marijuana use, domestic violence, and mental health problems were more common (borderline significance) in the abruption group. Smoking and preeclampsia were not found to be associated with placental abruption in this study. CONCLUSIONS: In this high-risk population, PRE-PROM and elevated homocysteine levels appear to represent the major risk factors for placental abruption.  相似文献   
100.
Based on the hot-plate algesiometric assay in conscious Sprague-Dawley rats, we observed that both guanabenz and clonidine, at a subcutaneous dose of 5 and 1 mg/kg, respectively, exhibited significant antinociceptive potencies. Paradoxical actions on the hot-plate responses, however, were exerted by guanabenz at lower doses, varying from hyperalgesia (1 mg/kg) to no effect (2 mg/kg). A pretreatment of clonidine (1 mg/kg) substantially potentiated the antinociceptive efficacy of the two latter doses, but failed to further augment the pain-suppressive action of guanabenz at 5 mg/kg. These interactive effects of the two alpha-adrenoceptor agonists suggest that they may share a common mechanism(s) in their analgesic actions.  相似文献   
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