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91.
The association of human immunodeficiency virus (HIV) acquisition with herpes simplex virus type 2 (HSV-2) was assessed among men who have sex with men (MSM) in a nested case-control study of 116 case subjects who seroconverted to HIV during follow-up and 342 control subjects who remained HIV seronegative, frequency-matched by follow-up duration and report of HIV-infected sex partner and unprotected anal sex. The baseline HSV-2 seroprevalence was higher among case (46%) than control (34%) subjects (P=.03); the HSV-2 seroincidence was 7% versus 4% (P=.3). Only 15% of HSV-2-infected MSM reported herpes outbreaks in the past year. HIV acquisition was associated with prior HSV-2 infection (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.1-2.9), reporting >12 sex partners (OR, 2.9; 95% CI, 1.4-6.3), and reporting fewer herpes outbreaks in the past year (OR, 0.3; 95% CI, 0.1-0.8). HSV-2 increases the risk of HIV acquisition, independent of recognized herpes lesions and behaviors reflecting potential HIV exposure. HSV-2 suppression with antiviral therapy should be evaluated as an HIV prevention strategy among MSM.  相似文献   
92.
BACKGROUND: Confirming the clinical suspicion of tuberculous meningitis (TBM) has always been problematic. Whilst smear and culture positivity are diagnostic, these tests have low sensitivity. The polymerase chain reaction (PCR) assay has given variable results. AIM: This study attempted to improve the diagnostic yield by: (a) increasing the cerebrospinal fluid (CSF) volumes; (b) testing the yield from three specimens of CSF assumed to represent lumbar, cervico-thoracic cord, and base of brain CSF samples; (c) undertaking PCR assays using multiple primer sets; and (d) using real-time PCR. METHOD: Patients suspected of having cranial or spinal meningeal tuberculosis were entered into the study. Three aliquots of CSF were subjected to smear, culture, and conventional and real-time PCR. Three sets of primers - IS6110, MPB64, and PT8/9 - were used. Patients were retrospectively classified into four categories: 'definite TB' (culture positive), 'probable TB' (clinical and other tests suggestive of TB), 'not TB', and 'uncertain diagnosis'. RESULTS: A total of 68 patients were studied. There were 20 patients classified as definite TB, 24 probable TB, 17 not TB, and seven uncertain diagnosis. Forty-eight of 57 (84.2%) patients tested were HIV seropositive. The IS6110 PCR was positive in 27 patients which included 18/20 culture positive cases, six in the probable TB group, and three in the not TB group. The MPB64 and PT8/9 primers did not increase the yield. Real-time PCR was positive in seven additional patients. Combining the definite and probable TB, the sensitivity of all PCR assays was 70.5% (31/44) and specificity 87.5% (21/24). CONCLUSION: Targeting multiple sites of the TB genome using conventional PCR did not increase the number of positive cases. Real-time PCR was more sensitive. However, all the current techniques are still too insensitive to confidently exclude the diagnosis on laboratory grounds.  相似文献   
93.
The importance of transdisciplinary collaboration is growing, though not much is known about how to measure collaboration patterns. The purpose of this paper is to present multiple ways of mapping and evaluating the growth of cross‐disciplinary partnerships over time. Social network analysis was used to examine the impact of a Clinical and Translational Science Award (CTSA) on collaboration patterns. Grant submissions from 2007 through 2010 and publications from 2007 through 2011 of Institute of Clinical and Translational Sciences (ICTS) members were examined. A Cohort Model examining the first‐year ICTS members demonstrated an overall increase in collaborations on grants and publications, as well as an increase in cross‐discipline collaboration as compared to within‐discipline. A Growth Model that included additional members over time demonstrated the same pattern for grant submissions, but a decrease in cross‐discipline collaboration as compared to within‐discipline collaboration for publications. ICTS members generally became more cross‐disciplinary in their collaborations during the CTSA. The exception of publications for the Growth Model may be due to the time lag between funding and publication, as well as pressure for younger scientists to publish in their own fields. Network analysis serves as a valuable tool for evaluating changes in scientific collaboration.  相似文献   
94.
95.
Myeloma is one of the most common malignancies that results in osteolytic lesions of the spine. Complications, including pathological fractures of the vertebrae and spinal cord compression, may cause severe pain, deformity and neurological sequelae. They may also have significant consequences for quality of life and prognosis for patients. For patients with known or newly diagnosed myeloma presenting with persistent back or radicular pain/weakness, early diagnosis of spinal myeloma disease is therefore essential to treat and prevent further deterioration. Magnetic resonance imaging is the initial imaging modality of choice for the evaluation of spinal disease. Treatment of the underlying malignancy with systemic chemotherapy together with supportive bisphosphonate treatment reduces further vertebral damage. Additional interventions such as cement augmentation, radiotherapy, or surgery are often necessary to prevent, treat and control spinal complications. However, optimal management is dependent on the individual nature of the spinal involvement and requires careful assessment and appropriate intervention throughout. This article reviews the treatment and management options for spinal myeloma disease and highlights the value of defined pathways to enable the proper management of patients affected by it.  相似文献   
96.
Objective: Attempts to categorize distinct functional gastrointestinal disorders based on reported symptoms continue but symptoms frequently overlap. The study objective was to use latent class analysis (LCA) which accommodates both continuous and discrete manifest variables to determine mutually exclusive subgroup assignments of a population-based sample using gastrointestinal symptom and patient data.

Materials and methods: A validated bowel disease questionnaire and somatic symptom questionnaire were mailed to an age and gender stratified randomly selected community sample. Responses to the symptom questions were dichotomized as frequent vs. infrequent based on Rome IV criteria. A LCA model was developed using a calibration subset and the results applied to the validation subset.

Results: There were 3831 total respondents (48%) with 3425 having complete data. The LCA algorithm was run for each of 10 (random) splits of the dataset and 2–6 latent classes were specified. Using the values of Akaike’s Information Criterion coefficient c to determine fit of the data, 4 latent classes yielded better values resulting in four subgroups: ‘asymptomatic,’ ‘upper’ abdominal symptoms, ‘lower’ abdominal symptoms, and ‘mixed’ (upper and lower abdomen).

Conclusions: Latent class analysis identified 4 groups based on symptoms. This approach resulted in differentiation by anatomical region rather than the Rome IV classification of symptoms.  相似文献   

97.

Purpose

Home sleep apnea tests (HSATs) are an alternative to attended polysomnograms (PSGs) when the pre-test probability for moderate to severe OSA is high. However, insurers often mandate use anytime OSA is suspected regardless of the pre-test probability. Our objective was to determine the ability of HSATs to rule in OSA when the pre-test probability of an apnea hypopnea index (AHI) in the moderate to severe range is low.

Methods

Patients who underwent HSATs were characterized as low or high pre-test probability based on the presence of two symptoms of the STOP instrument plus either BMI >?35 or male gender. The odds of HSAT diagnostic for OSA dependent on pre-test probability was calculated. Stepwise selection determined predictors of non-diagnostic HSAT. As PSG is performed after HSATs that do not confirm OSA, false negative results were assessed.

Results

Among 196 individuals, pre-test probability was low in 74 (38%) and high in 122 (62%). A lower percentage of individuals with a low versus high pre-test probability for moderate to severe OSA had HSAT results that confirmed OSA (61 versus 84%, p?=?0.0002) resulting in an odds ratio (OR) of 0.29 for confirmatory HSAT in the low pre-test probability group (95% CI [0.146, 0.563]). Multivariate logistic regression demonstrated that age ≤?50 (OR 3.10 [1.24–7.73]), female gender (OR 3.58[1.50–8.66]), non-enlarged neck circumference (OR 11.50 [2.50–52.93]), and the absence of loud snoring (OR 3.47 [1.30–9.25]) best predicted non-diagnostic HSAT. OSA was diagnosed by PSG in 54% of individuals with negative HSAT which was similar in both pre-test probability groups.

Conclusion

HSATs should be reserved for individuals with high pre-test probability for moderate to severe disease as opposed to any individual with suspected OSA.
  相似文献   
98.
99.
Local tumor recurrence after curative resection for rectal cancer   总被引:6,自引:6,他引:6  
Local tumor recurrence rates after curative rectal cancer surgery with the end-to-end anastomosis stapler (EEA®) are reportedly high. Therefore, a retrospective review in ten Yale-affiliated hospitals was undertaken to establish the outcome of surgical resection for rectal cancer in this patient population. Of those 373 patients who had had curative resections, 192 (52 percent) were abdominoperineal resections (APR); 105 patients (28 percent) had restorative resections with sutured anastomoses, and the EEA stapler was used in 76 patients (20 percent). There was an equal distribution of tumors in the various Dukes' stages in all three procedures. Local tumor recurrence was: APR 19 percent, SUT 17 percent, and EEA 24 percent, but local tumor recurrence was more frequent after EEA than APR for tumors 7 to 10 cm from the anal verge (32 vs. 13 percent, respectively,P<0.05), and the time to recurrence was least in EEA patients. It is concluded that local tumor recurrence is higher than expected for all three procedures and that the EEA stapler was associated with a greater risk of local tumor recurrence. These findings are attributed to surgeon-related technical operative factors rather than to the nature of the tumors themselves.  相似文献   
100.
Elimination programs for Wuchereria bancrofti and Onchocerca volvulus are in critical need of sensitive, specific, and point-of-contact (POC) tools that can be used for surveillance years beyond cessation of mass drug administration when infection intensities are low. Previously, Wb123 and Ov16 were identified individually as potential filarial antigens for an antibody-based POC test. The present study compares single-antigen Wb123- and Ov16-based POC tests with an integrated configuration to detect antibodies to Wb123 and Ov16 simultaneously. Wb123 and Ov16 isolates were striped onto lateral flow strips containing anti-IgG4. Sera from W. bancrofti-, O. volvulus-, and other helminth-infected or -uninfected individuals were added to the strips with buffer. Strips were read for the appearance of a positive or negative test line for both antigens at 20 min and following drying. Sensitivity, specificity, and predictive values were calculated for the single-antigen and biplex strips. Single and biplex lateral flow strips showed nearly identical results, with >90% sensitivity for Ov16 and >92% sensitivity for Wb123. Overall specificities for the single and biplex tests were 98% and 96% for Ov16 and Wb123, respectively. Biplex tests performed as well as the single-antigen tests regardless of the intensity of patient IgG4 response. The high sensitivity and specificity make these new biplex tests extremely useful for POC long-term surveillance following mass drug administration in Africa that should reduce time and cost in areas where bancroftian filariasis and onchocerciasis are coendemic.  相似文献   
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