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61.
62.
This article reports the results of a peer-led HIV prevention education and condom promotion program among transport workers in Kaolack, Senegal. As part of a 2-year longitudinal follow-up study, changes in men's AIDS-related knowledge, sexual behavior, condom use, and perceived barriers to condom use were evaluated by self-reports obtained from a systematic sample of transport workers interviewed before and after intervention. In addition to men's self-reports, preintervention and postintervention data on men's sexual and condom use behavior were gathered from a sample of licensed, commercial sex workers, who cited transport workers as their primary source of clients. Significant increases in men's HIV-related knowledge, previous use of condoms (from 30.4% to 53.5%), and consistent condom use with regular sex partners were documented over the study period, as were significant declines in perceived barriers to condom use. Though men reported significantly fewer sexual encounters with casual and commercial partners at follow-up compared to baseline, these data were unreliable. Women's postintervention reports indicate that a greater proportion of clients (including, but not limited to transport workers) "always" agree to use condoms (p < .01) compared with baseline and that fewer men offer more money for unprotected sex (p < .01). However, women also report taking greater initiative in the mechanics of condom use (supplying the condom, putting it on, and taking it off) than they did prior to the intervention, and significantly (p < .05) fewer women think that most of their clients know how to use a condom. The findings indicate that the peer-mediated intervention had a positive impact on several important outcomes measured and suggest that HIV prevention efforts need to focus on male client groups despite the logistical and methodological challenges.  相似文献   
63.
To evaluate the chronic effects of exposure to cotton dust, a 15-yr follow-up study in cotton textile workers was performed in Shanghai, China from 1981 to 1996. Testing occurred four times during the 15-yr period. The achieved follow-up rates were 76-88% of the original 447 cotton textile workers, and 70-85% of the original 472 silk textile workers (as a control group). Identical questionnaires, equipment, and methods were used throughout the study. The prevalence of byssinosis increased over time in cotton workers, with 15.3% at the last survey versus 7.6% at the baseline, whereas no byssinosis was found in silk workers. More workers in the cotton group consistently reported symptoms than in the silk group, although symptom reporting varied considerably from survey to survey. Cotton workers had small, but significantly greater, adjusted annual declines in FEV(1) and FVC than did the silk workers. Years worked in cotton mills, high level of exposure to endotoxin, and across-shift drops in FEV(1) were found to be significant determinants for longitudinal change in FEV(1), after controlling for appropriate confounders. Furthermore, there were statistically significant associations between excessive loss of FEV(1) and byssinosis, chest tightness at work, and chronic bronchitis in cotton workers. Workers who consistently (three or four of the surveys) reported byssinosis or chest tightness at work had a significantly greater 15-yr loss of FEV(1). We conclude that long-term exposure to cotton dust is associated with chronic or permanent obstructive impairments. Consistent reporting of respiratory symptoms, including byssinosis and chest tightness at work, is of value to predict the magnitude and severity of chronic impairments in textile workers.  相似文献   
64.
Purified human platelets were found to contain a collagenase inhibitor that is immunologically, functionally, and chromatographically identical to that produced by human skin fibroblasts. None of the other formed elements of the blood (erythrocytes, granulocytes, mononuclear cells) possessed detectable quantities of this protein. Virtually all the collagenase inhibitor contained within platelets was released following platelet activation with thrombin. Similarly, platelet activation accompanying blood clotting also resulted in the release of this protein, the ratio of plasma to serum inhibitor levels being approximately equal to 0.5. When platelets were subjected to subcellular fractionation, essentially all of the platelet-associated collagenase inhibitor was found to be located in the alpha-granule. Studies with radiolabeled inhibitor failed to detect uptake of inhibitor by platelets. Furthermore, immunologically reactive protein of similar quantity to that found in platelets was identified in human megakaryocyte lysates. Thus, the data suggest that the collagenase inhibitor is endogenously produced and stored within platelet alpha-granules. The platelet-derived collagenase inhibitor was antigenically identical to the collagenase inhibitor from human skin fibroblasts in double immunodiffusion and, like its fibroblast counterpart, inhibited collagenase on a 1:1 stoichiometric basis. When subjected to several of the chromatographic procedures utilized to purify the fibroblast protein, the platelet inhibitor behaved in an indistinguishable manner. Platelet factor 4, previously reported to be a collagenase inhibitor, was found to be immunologically unrelated to the platelet-derived collagenase inhibitor. Furthermore, platelet factor 4 displayed no collagenase inhibitory activity. Although the function of platelet-derived collagenase inhibitor is unknown, such a protein released by activated platelets may serve to regulate collagen turnover during the early stages of the inflammatory process.  相似文献   
65.
STUDY OBJECTIVES: The mechanism(s) by which nasal continuous positive airway pressure (CPAP) is effective in the treatment of Cheyne-Stokes respiration (CSR) in patients with congestive heart failure (CHF) remains uncertain, and may involve an increase in total oxygen body stores (dampening), changes in central and peripheral controller gain, and/or improvement in cardiac function. The purpose of this study was to evaluate the effects of nasal CPAP on total oxygen stores, as measured by the rate of fall of arterial oxyhemoglobin saturation (dSaO(2)/dt), to determine if dampening may play a role in the attenuation of CSR in patients with CHF. DESIGN: Prospective controlled trial. SETTING: University hospital. PATIENTS: Nine male patients (mean +/- SD age, 59 +/- 8 years) with CHF and a mean left ventricular ejection fraction (LVEF) of 16 +/- 4%. Interventions and measurements: All patients had known CSR, as identified on a baseline polysomnographic study. Patients then underwent repeat polysomnography while receiving nasal CPAP (9 +/- 0.3 cm H(2)O). The polysomnography consisted of recording of breathing pattern, pulse oximetry, and EEG. dSaO(2)/dt was measured as the slope of a line drawn adjacent to the falling linear portion of the arterial oxygen saturation (SaO(2)) curve associated with a central apnea. All patients underwent echocardiography and right-heart catheterization within 1 month of the study to measure LVEF and cardiac hemodynamics, respectively. RESULTS: There was a significant decrease in the apnea-hypopnea index (AHI) with nasal CPAP, from 44 +/- 27 events per hour at baseline to 15 +/- 24 events per hour with nasal CPAP (p = 0.004). When compared to baseline, dSaO(2)/dt significantly decreased with nasal CPAP from 0.42 +/- 0.15% to 0.20 +/- 0.07%/s (p < 0.001). The postapneic SaO(2), when compared to baseline, significantly increased with nasal CPAP, from 87 +/- 5% to 91 +/- 4% (p < 0.05). The preapneic SaO(2) did not significantly change, from a baseline of 96 +/- 2% to 96 +/- 3% with nasal CPAP (p = 0.8). When compared to baseline, the apnea duration and heart rate did not change with nasal CPAP. While there was a significant correlation noted between baseline postapneic SaO(2) and dSaO(2)/dt (r = 0.8, p = 0.02), no correlation was seen between baseline preapneic SaO(2) and dSaO(2)/dt (r = 0.1, p = 0.7). A significant correlation was noted between baseline dSaO(2)/dt and the AHI (r = 0.7, p = 0.02). With CPAP, there was a significant correlation noted between dSaO(2)/dt and the AHI (R = 0.7, p = 0.04), but no correlation was noted between dSaO(2)/dt and postapneic SaO(2) (R = 0.1, p = 0.8). CONCLUSION: Nasal CPAP significantly decreases dSaO(2)/dt and thus increases total body oxygen stores in patients with CSR and CHF. By increasing oxygen body stores, dampening may be one of the mechanisms responsible for the attenuation of CSR seen with nasal CPAP.  相似文献   
66.

Classes of obsessive-compulsive features differing both quantitatively and qualitatively have been linked to gambling disorder. This secondary data analysis sought to extend this line of investigation to examine the extent to which previously reported latent obsessive-compulsive classes may relate to externalizing conditions in a sample of 1675 twin male veterans recruited and surveyed for studies of gambling behaviors/disorder. Using latent class analysis and multivariate regression, we found that participants who reported the highest levels of obsessive-compulsive features were more likely to meet criteria for cannabis abuse and dependence and antisocial personality disorder. When adjusting for co-occurring disorders, the relationship with antisocial personality disorder remained significant whereas those for cannabis use disorders did not. These results highlight the potential utility of considering obsessive-compulsive features within a transdiagnostic framework and suggest that specific externalizing disorders have important links to obsessive-compulsive features. Future research is needed to extend these findings to other samples.

  相似文献   
67.
BALB/c mice were immunized with three A-myeloma proteins of BALB/c-2 or BALB/c origin (produced by plasmacytomas MOPC-315, MOPC-460, Adj. PC-22A). Noncross reacting antibodies were formed against Proteins-315 and 460, but the response to Protein-22A was marginal. Proteins-315 and 460 have anti-dinitrophenyl activity, and their reactions with the corresponding BALB/c antibodies were inhibited by dinitrophenyl ligands. It appears that antibodies can be formed in BALB/c mice against unique "idiotypic" determinants in the ligand-binding sites of some BALB/c mycloma proteins.  相似文献   
68.
OBJECTIVES: We aimed to assess the Severity of Dyspepsia Assessment (SODA) scales as measures of change in dyspepsia-related health in a blinded, randomized, controlled trial in arthritis patients treated with nonsteroidal anti-inflammatory drugs. METHODS: Three thousand nine hundred seven arthritis patients completed SODA at baseline and weeks 4, 13, 26, and 52 and/or at early termination. Using baseline and 4-wk data, reliability was evaluated with Cronbach's a and the intraclass correlation coefficient (ICC). Dyspepsia adverse events were defined based on a combined set of World Health Organization Adverse Reaction Terminology terms. The ability of SODA to measure change in dyspepsia-related health was evaluated by comparing SODA change scores by dyspepsia adverse event severity level and withdrawal status. Responsiveness was further evaluated by the area under the curve (AUC) from receiver operating characteristic curves using withdrawal due to dyspepsia as the criterion. RESULTS: The SODA scales--Pain Intensity (alpha = 0.93), Non Pain Symptoms (alpha = 0.82), and Satisfaction (alpha = 0.89)--demonstrated excellent internal consistency reliability using baseline data. Reproducibility was fair to good: Pain Intensity ICC = 0.49, Non Pain Symptoms ICC = 0.61, and Satisfaction ICC = 0.45. SODA change scores (4-wk score - baseline score) increased, or worsened, with increasing dyspepsia severity and differentiated between adjacent levels of dyspepsia severity for eight of nine adjacent comparisons (p < 0.05). SODA change scores also differentiated between those who did and did not withdraw (p < 0.001). Responsiveness was highest with the Pain Intensity scale (AUC = 0.78), followed by the Non Pain Symptoms (AUC = 0.74) and Satisfaction (AUC = 0.75) scales. CONCLUSIONS: SODA is a reliable, valid instrument for use as a measure of dyspepsia tolerability in future clinical trials involving cyclo-oxygenase-2-specific and/or traditional nonsteroidal anti-inflammatory drugs.  相似文献   
69.
Benign paroxysmal positional vertigo of the superior semicircular canal is a rare form of BPPV. It accounts for 1% to 3% of cases. The characteristic nystagmus is positional, down‐beating, with a torsional component elicited by the Dix‐Hallpike maneuver. Symptoms of superior semicircular canal BPPV often resolve spontaneously; however, it can be refractory to repositioning maneuvers. Surgical management is described for posterior semicircular canal BPPV. To date, however, there is only one reported case of surgical management for superior semicircular canal BPPV. Here we show video documentation of positional, down‐beating nystagmus and describe a case of superior semicircular canal BPPV requiring canal occlusion with successful resolution of symptoms. Laryngoscope, 125:1965–1967, 2015  相似文献   
70.
Both feeding and mating initiate an increase in the number of the active neurosecretory cells (NSC) in certain regions of the tick's brain. NS activity was apparent already within 1 hr after a blood meal. Highest number of active cells was observed 24 hr after the meal. This was followed by a decline in number of active NSC during 10–14 days. In virgin females, a second, somewhat lower peak in NS activity appeared a fortnight after a blood meal. This second peak is possibly related to cycles in oogenesis of the virgin ticks.  相似文献   
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