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71.
Aim: The aim of the study was to investigate whether salivary mineral content may be associated with bone status in women after menopause. Material and methods: The study group consisted of 125 postmenopausal women aged 64.3 ± 6.9 yr, derived from the epidemiological SilesiaOsteoActive Study. All participants underwent hip and spine bone densitometry using dual energy X-ray absorptiometry, dental examination, and saliva content analysis. Data for salivary pH, copper, calcium, phosphorus, and zinc concentrations were evaluated. Results: Mean femoral neck bone mineral density (BMD) was 0.739 ± 0.118 g/cm2, total hip BMD 0.891 ± 0.14 g/cm2, and spine BMD 0.868 ± 0.14 g/cm2. Salivary pH was significantly lower in women with spinal osteoporosis defined as T-score below ?2.5, compared to individuals with normal BMD (pH: 6.65 ± 0.67 vs 6.96 ± 0.58, p < 0.05). There was a significant though weak inverse correlation between Ca concentration in saliva and femoral neck BMD (r = ?0.23, p < 0.05). Conclusions: High salivary calcium content and low salivary pH may be indicative of low hip and decreased spine BMD, respectively. These associations may reflect demineralization process (calcium redistribution) influencing bone, and a negative effect of acidity on mineral tissues, although causal pathway remains not clear.  相似文献   
72.
Solid organ transplant (SOT) recipients run a high risk for adverse outcomes from COVID-19, with reported mortality around 19%. We retrospectively reviewed all known Swedish SOT recipients with RT-PCR confirmed COVID-19 between March 1 and November 20, 2020 and analyzed patient characteristics, management, and outcome. We identified 230 patients with a median age of 54.0 years (13.2), who were predominantly male (64%). Most patients were hospitalized (64%), but 36% remained outpatients. Age >50 and male sex were among predictors of transition from outpatient to inpatient status. National early warning Score 2 (NEWS2) at presentation was higher in non-survivors. Thirty-day all-cause mortality was 9.6% (15.0% for inpatients), increased with age and BMI, and was higher in men. Renal function decreased during COVID-19 but recovered in most patients. SARS-CoV-2 antibodies were identified in 78% of patients at 1–2 months post-infection. Nucleocapsid-specific antibodies decreased to 38% after 6–7 months, while spike-specific antibody responses were more durable. Seroprevalence in 559 asymptomatic patients was 1.4%. Many patients can be managed on an outpatient basis aided by risk stratification with age, sex, and NEWS2 score. Factors associated with adverse outcomes include older age, male sex, greater BMI, and a higher NEWS2 score.  相似文献   
73.
74.
Renal sodium handling and microsomal Na+–K+-ATPase activity in kidney cortex, medulla and papilla of rats with streptozotocin-induced diabetes mellitus (DM) was studied.During 7 days following the administration of streptozotocin GFR, urinary excretion, filtered load and tubular reabsorption of Na+ averaged (mean±SE) 1.18±0.016 ml/min, 1.74±0.14, 177.3±8.9 and 175.6±8.9 mEq/min respectively in experimental rats as compared to corresponding rates of 0.85±0.04 (P<0.001), 0.85±0.03 (P<0.001), 129.8±5.8 (P<0.001) and 129±5.8 (P<0.001) respectively in the control rats.The activity of microsomal Na–K-ATPase in the kidney cortex, medulla and papilla of the control group was (mean±SE) 44.7±1.7, 150±7.5 and 37.4±3.6 (moles Pi/mg prot/h) respectively. 24 h after DM induction Na–K-ATPase activity in the cortex rose to 59.3±2.4 (P<0.001) and remained high after 3 and 7 days. Medullary Na–K-ATPase activity was unchanged 24 h after streptozotocin administration but was markedly increased to 260±9 (P<0.001) after 3 days and remained high after 7 days.These findings show that stretozotocin-induced DM in rats causes a substantial increase in GFR which is associated with a net increase in filtered and reabsorbed load of Na+ and natriuresis. These alterations are accompanied by a marked increase in Na–K-ATPase activity in renal medulla and in the cortex.This study was supported by the Morton S. Kaufman Hemodialysis Foundation and by the Joint Research Fund of the Hebrew University and Hadassah  相似文献   
75.
This paper presents findings from a study investigating differences in the importance of nineteen criteria in the choice of professionals from three professional groups--physicians, dentists, and lawyers. Knowledge is the most important for all three groups but is less so for doctors. Discussions about the problem and its treatment are both less important for dentists. Six characteristics of professional service providers are used to explain differences.  相似文献   
76.

Objectives

There are two alternative hypotheses regarding bidirectional associations between self-efficacy and planning in predicting health behaviour change: self-efficacy may establish planning (cultivation hypothesis) or planning may enable the formation of self-efficacy (enabling hypothesis). This study investigates the order in which these two social cognitions are linked in adult–adult dyads in the context of sedentary behaviours (SB).

Design

A longitudinal study with 4 measurement points, spanning 8 months.

Methods

A total of 320 dyads (age: 18–90 years) were enrolled. Dyads included a focus person (who received the recommendation to reduce SB and intended to change their SB), and their partners, who were willing to support the focus persons and intended to reduce their own SB as well. Data were collected at Time 1 (T1), Time 2 (1 week later, T2), Time 3 (T3, 2 months after T1) and Time 4 (T4, 8 months after T1). SB was measured with accelerometers at (T1 and T4). Mediation models with individual and dyadic reciprocal effects were tested with path analyses.

Results

Only one indirect effect was found: A higher level of partners' SB reduction-specific self-efficacy at T2 was related to the focus person's more frequent planning to reduce SB at T3, which, in turn, predicted lower SB time among partners at T4.

Conclusions

The findings provide partial support for the cultivation model (self-efficacy prompting planning) and for dyadic reciprocal associations in the context of SB time reduction among adult dyads.  相似文献   
77.
The p53 gene located at chromosome 17pl3 is found to be altered (allelic loss or other mutation) in multiple human cancers, including osteosarcomas. The mutated gene produces a protein with a prolonged half-life thus rendering it detectable by conventional immunohistochemistry. We examined the correlation between p53 expression and clinical prognosis as well as response to therapy. Twentyone patients with previously untreated and histologically verified highly malignant osteosarcoma were used for this study. Biopsy material taken both prior to the start of COSS 91 protocol and at the time of surgery (ten weeks later) was examined for alterations in p53 protein expression and drug resistance. Two patients who had strong (+++) p53 protein expression and three others who became positive during the chemotherapy had significantly worse prognosis (all of them died within one year) than those who showed no p53 expression both at biopsy and after chemotherapy (all 11 patients are alive, average follow-up time: 3.5 years). All patients who showed any kind of positive p53 protein expression on initial biopsy were non-respon-ders to chemotherapy. In contrast, 69% (9 out of 13) of those who exhibited no p53 expression on initial biopsy were responders or intermediate responders to chemotherapy. We concluded that p53 expression may be a useful prognostic factor in osteosarcomas. The direct correlation between p53 positive expression and resistance to therapy can help in identifying patients who are in need of a more vigorous or different chemotherapeutical protocol.  相似文献   
78.
This paper presents the results of an exploratory study designed to (1) ascertain the primary sources of information patients use when selecting physicians and (2) identify differences in patient selection factor importance by type of physician under consideration (specialists versus generalists). The results support previous research which finds word-of-mouth and physician referrals the primary sources of information. Selection factors considered important when selecting a generalist were significantly different from factors considered important when selecting a specialist. Implications of the study's findings for effective physician marketing and future research are discussed.  相似文献   
79.
St. Paul-Ramsey Medical Center in St. Paul, MN became one of the first hospitals in the United States to initiate a "stockless" par level inventory system. Successes with stockless led the hospital to look at implementing it in the OR to achieve a reduction of expense to revenue. Materiel Management and Surgical Services discussed a number of issues relevant to implementing a stockless program, including product flow, accuracy and cost of case carts and preference cards, item pricing, committed usage of items brought into the system and establishment of a steering committee. Specific OR issues and practices required evaluation and adjustment, such as the routine use of emergency direct ordering. Information systems support was brought in and a products committee established to do education and oversee the program. Savings for 1993-94 were $185,146.  相似文献   
80.
Patterns of success and failure with laparoscopic Toupet fundoplication   总被引:5,自引:4,他引:1  
Bell RC  Hanna P  Mills MR  Bowrey D 《Surgical endoscopy》1999,13(12):1189-1194
Background: Advocates of the Toupet partial fundoplication claim that the procedure has a lower rate of the side effects of dysphagia and gas bloat than a complete Nissen fundoplication. However, there is increasing recognition that reflux control is not always as good with the Toupet procedure as with the Nissen. Therefore, we set out to evaluate the factors contributing to success and failure in patients who underwent laparoscopic modified Toupet fundoplication (LTF). Methods: A total of 143 patients undergoing LTF for documented gastroesophageal reflux disease (GERD) were evaluated prospectively in regard to their outcomes over a 4-year period. All patients had preoperative esophagogastroduodenoscopy (EGD) and manometry; 24-h pH testing was used selectively. Esophageal manometry was requested of all patients 6 weeks postoperatively. Clinical follow-up was by office visit or questionnaire every 6 months after surgery; patients with significant problems were investigated further. Failure was defined as the development of recurrent reflux documented by endoscopy, 24-h pH test, or wrap disruption on barium swallow, or severe dysphagia persisting >3 months and requiring surgical revision. Results: At a mean follow-up of 30 months (range, 3–51), 21 of 143 patients failed LTF; two had dysphagia and 19 had recurrent reflux. Failure was associated with preoperative findings of a defective lower esophageal sphincter (LES) (14/21), complicated esophagitis (13/21), and failure to divide short gastric vessels (12/19) (chi-square p < 0.05). Defective esophageal body peristalsis, present in 14 patients, resulted in failure in six cases. Presence of either complicated esophagitis or a defective LES was associated with a 3-year 50% success rate, whereas presence of mild esophagitis and a normal LES was reflected in a 96% 3-year success rate. Conclusion: Laparoscopic Toupet fundoplication should be reserved for milder cases of GERD, as assessed by manometry and endoscopy. Received: 29 June 1998/Accepted: 2 July 1999  相似文献   
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